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					Bausch & Lomb Automated Lens Measurement System                                Project #05427



Executive Summary

       Bausch & Lomb brought this project to R.I.T. in order for the Senior Design team to

develop the most cost effective non-contact method of evaluating the center thickness of a

contact lens.

       In order to produce a contact lens, a mold is produced, the lens is cast and cured, then it is

hydrated, inspected and packaged for shipment. The current process during the inspection uses a

mechanical contact gauge to determine the center thickness. Once this measurement is

performed, the lens must be discarded. The new requirements specified by Bausch & Lomb

maintain that the new system must be non-contact in order to eliminate the discarding of any

good product.

       As stated above, the requirements were determined after consulting with the Bausch &

Lomb Project Coordinator and Sponsor. After this was finalized all of the other appropriate

documentation was put into place. The team could then begin researching concepts.

       This project is different than most because it was extremely research intensive. The team

was required to spend a significant amount of time conducting research into various technologies

and companies that currently exist and could provide the proper equipment. It is outside of the

scope of the project for the team to construct its own device from scratch, so the research was

critical to find appropriate vendors that could be evaluated.

       After the initial large grouping of companies was narrowed down to the top eight that

might be capable of meeting the projects needs, a feasibility assessment was conducted. This

feasibility confirmed the teams’ opinion of what the top three companies were that should be

pursued further. On a parallel track, all of the companies were sent testing samples. The results

from the vendor testing would aid the team in determining what the top companies were. The



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Bausch & Lomb Automated Lens Measurement System                                                              Project #05427


top scoring companies from the teams’ opinion, feasibility assessment and testing results were

Lumetrics, Micro-Epsilon, and Panametrics – NDT.

          These top companies will have their units brought into Bausch & Lomb for the team to

conduct an analysis of how capable they are. This analysis, along with final recommendations,

cost benefit analysis, and a manufacturing integration package are slated to be completed at the

end of Senior Design II. In order to accomplish all of these goals given the one-quarter

remaining, the team has adopted a very aggressive timeline in order to ensure the projects

success. As a whole, the team is very proud of the progress to date, is determined in achieving

success, and confident in the path that lies ahead.




EXECUTIVE SUMMARY ....................................................................................................... 1
1.0 INTRODUCTION ............................................................................................................. 5
  1.1     BACKGROUND ..................................................................................................... 5
     1.1.1 Current Measurement Method ......................................................................... 6
     1.1.2 Desired Method ................................................................................................. 6



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Bausch & Lomb Automated Lens Measurement System                                                                   Project #05427


     1.1.3 Possible Points of Integration........................................................................... 6
  1.2 CONFIDENTIALITY AND PROTECTION OF INTELLECTUAL PROPERTY ................... 7
2.0 NEEDS ASSESSMENT ................................................................................................ 8
  2.1 NEEDS ASSESSMENT OVERVIEW .............................................................................. 8
  2.2 REQUIREMENTS – MEASUREMENTS......................................................................... 8
     2.2.1 Non-Contact ...................................................................................................... 9
     2.2.2 Integration ......................................................................................................... 9
     2.2.3 PLC Interface .................................................................................................. 10
     2.2.4 User Interface .................................................................................................. 10
     2.2.5 Extensibility / Flexibility ................................................................................. 11
  2.3 MISSION STATEMENT ............................................................................................. 11
  2.4 GOALS & OBJECTIVES ........................................................................................... 11
  2.5 TEAM CHARTER ..................................................................................................... 12
  2.6 CONSTRAINTS ......................................................................................................... 13
  2.7 RISK ASSESSMENT .................................................................................................. 14
  2.8 BUDGET ................................................................................................................... 15
3.0 CONCEPT RESEARCH .................................................................................................. 16
  3.1 POSSIBLE TECHNOLOGIES AND DISCOUNTED TECHNOLOGIES ............................ 16
     3.1.1 Capacitance Method ....................................................................................... 16
     3.1.2 Laser Triangulation ........................................................................................ 17
     3.1.3 Optical Spectrometer ....................................................................................... 17
     3.1.4 Laser (Autofocus) ............................................................................................ 18
     3.1.5 Ultrasonic ........................................................................................................ 19
     3.1.6 Vision System .................................................................................................. 19
     3.1.7 Mechanical Contact System............................................................................ 20
  3.2 LONG LIST/SOURCES .............................................................................................. 21
  3.3 SHORT LIST............................................................................................................. 21
  3.4 REASONS NOT TO PURSUE CERTAIN COMPANIES ................................................. 22
  3.5 METHOD FOR GATHERING TECHNOLOGY AND COMPANY INFORMATION .......... 23
  3.6 PATENT SEARCH ..................................................................................................... 24
     3.6.1 Patent Information .......................................................................................... 24
  3.7 PRODUCT SPECIFICATION RESEARCH ................................................................... 27
     3.7.1 Contact Lens Quick Reference Guide ............................................................ 28
     3.7.2 Radius of curvature ......................................................................................... 28
     3.7.3 Mold Information ............................................................................................ 28
     3.7.4 Cost Research .................................................................................................. 29
     3.7.5 Centration of Lens .......................................................................................... 29
4.0 FEASIBILITY ................................................................................................................ 30
  4.1 THE SHORT LIST REVISITED .................................................................................. 30
  4.2 JUDGING CRITERIA ................................................................................................ 30
  4.3 WEIGHTING CRITERIA ........................................................................................... 31
  4.4 SCORING ................................................................................................................. 32
  4.5 SAMPLE TEST RESULTS .......................................................................................... 33
  4.6 THE TOP THREE ..................................................................................................... 35
5.0 DESIGNS ...................................................................................................................... 35




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Bausch & Lomb Automated Lens Measurement System                                                               Project #05427


  5.1 LUMETRICS ............................................................................................................. 35
  5.2 MICRO-EPSILON ..................................................................................................... 38
  5.3 PANAMETRICS ......................................................................................................... 41
6.0 CONCLUSION ............................................................................................................... 44
  6.1 SUMMARY ............................................................................................................... 44
  6.2 GOALS FOR SENIOR DESIGN II ............................................................................... 44
  6.3 ACTION PLAN TO ACHIEVE GOALS ....................................................................... 44
7.0 REFERENCES ............................................................................................................... 46




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Bausch & Lomb Automated Lens Measurement System                                   Project #05427



1.0 Introduction


        With increased demand for contact lenses, Bausch & Lomb has seen a need to ramp up

its production. To do so, Bausch & Lomb is in the process of building new fully automated

production lines. To ensure every product meets their high quality standards, lens measurements,

including center thickness, are conducted as part of the production process. The team has been

requested to research and evaluate methods and devices available to perform an automated, non-

contact central thickness measurement. Based on the teams technical and cost benefit evaluations

of the methods/devices available, the design team will build an offline station to functionally test

the capabilities of the measurement system(s) chosen.




    Molding          Casting/Curing         Release       Hydration      Inspection         Packaging



Figure 1.0 – Process flow for contact lens production




1.1 Background

    The center thickness of the contact lens is critical to maintain the correct optical properties as

well as to ensure comfort for the consumer. If the lens is too thin it will not perform properly

and may rip. If the lens is too thick, the optical properties will be compromised and the

consumer will not be comfortable wearing the lens. Therefore, verifying that the product has the

proper center thickness is critical to maintain the product integrity.




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Bausch & Lomb Automated Lens Measurement System                                   Project #05427


1.1.1 Current Measurement Method

       Bausch & Lomb currently performs this lens central thickness measurement on a manual

offline station, which mechanically contacts the lens to perform the measurement. The lens is in

the wet state at the time of measurement. After the measurement has been made, the lens must be

discarded as the mechanical contact that the measurement device makes with the lens may

impose defects on the surface of the lens. Since lenses must be thrown out after the current

measurement is performed, lens central thickness is monitored at an audit level of between 1 and

1.5 percent, rather than at 100 Percent of Lenses Made (PLM).



1.1.2 Desired Method

       Bausch & Lomb would like the design team to develop an automated, non-contact

measurement system for numerous reasons. A non-contact method would allow B&L to measure

the central thickness without discarding product. Since no contact would be made with the lens

surface, there would be no possibility of damaging the surface of the lens. The automated system

would also lower production costs and increase quality. The system would not require an

operator, so the non-value added labor cost would be decreased substantially. A non-contact

device would allow B&L to measure every lens’s central thickness, which would insure a higher

quality product.



1.1.3 Possible Points of Integration

       In order to reduce costs further we will also determine the manufacturing process step at

which it is best to perform the central thickness measurement. During the manufacturing process

the lens is either in the dry state or the wet state. In the dry state, there are three scenarios where




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Bausch & Lomb Automated Lens Measurement System                                 Project #05427


the lens central thickness can be measured, including: while both mold halves are still assembled,

after the mold has been de-capped, and after the lens has been released from the mold. Since the

lens starts off in the dry state, it would be beneficial to perform the measurement at some point

during the dry stage, as it would allow bad product to be discarded at an earlier stage of

production.

       In the wet state, the lens can be measured in either the final blister or the wet cell used for

cosmetic inspection. Although we do not see inspecting in the blister as a cost-effective method,

we will keep it as a possible point of integration in case a measurement cannot be performed

elsewhere in the process.

       As part of our development process, we will consider each of the scenarios mentioned

above, and evaluate the pros and cons of each. We will attempt to find systems capable of

measuring in more than one of the process steps above.



1.2 Confidentiality and Protection of Intellectual Property

       Given the highly competitive nature of the contact lens manufacturing industry, Bausch

& Lomb has required that a Bausch & Lomb representative, prior to its public release, review all

information disclosed in any publication regarding this project. With that being said, it is to be

understood that certain portions of this report may not contain all information that was

discovered during the research and concept development phases of this design project.




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Bausch & Lomb Automated Lens Measurement System                                  Project #05427




2.0 Needs Assessment

2.1 Needs Assessment Overview

       In performing a needs assessment for this project, the team in cooperation with Bausch &

Lomb representatives outlined and agreed to the requirements of the Automated Lens

Measurement System. With these requirements an overall mission statement was formed along

with team goals and objectives. The team then broke up the member roles and responsibilities.



2.2 Requirements – Measurements

       The first requirements specify the thickness range to be measured. The range for this

project is 50 – 250 μm. As a frame of reference, a typical human hair is approximately 50 μm

and standard sheet of 8.5 x 11 printer paper is approximately 185 μm. The thickness requirement

is born out of the need to measure different products such as single power correction, multifocal

correction or toric lenses and their range of Stock Keeping Units (SKU’s).

       The tolerance specified for the measurement is ±10 μm. This requirement is based

around the optical properties of the lens and the comfort realized by the consumer. Since these

characteristics are directly related to its center thickness, the specified tolerance must be held.

       A gauge repeatability and reproducibility less than 18% is also required. This is a Bausch

& Lomb quality requirement, which insures both precision and accuracy of the measurement are

maintained at an acceptable level.

       The measurement area of the system is not to exceed 1.0 square mm. This is due to the

lens geometry, specifically the anterior and posterior curvatures as well as the thickness profile

across the lens. A limit of 1.0 square mm holds the measurement to the central point of the lens.



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Bausch & Lomb Automated Lens Measurement System                                  Project #05427




2.2.1 Non-Contact

       Bausch & Lomb stressed the non-contact requirement from the beginning. It has greatly

impacted the project by increasing both complication of making the measurement and cost. This

requirement is a quality/yield based. The word contact is similar to bump, crash, jolt and strike

as found in a thesaurus. This is undesirable from a quality standpoint, regardless of how gentle

the contact is. The underlying theme remains the same, the more lens handling, and the more

chances there are for cosmetic defects to occur. Lenses are extremely brittle and easily subject to

cosmetic defects in the dry state. While the lens is more durable in the wet state, there is still a

possibility of causing cosmetic defects.

       There also exists the possibility of causing a mark on the lens visible to process machine

vision systems. These systems are trained to find actual defects on lenses and are antagonized by

non-defect process signatures, which appear similar to actual cosmetic defects. Elimination of a

contact method further limits the possibility of false rejects at the inspection point.




2.2.2 Integration

       The end goal of the project is to have a fully functional standalone test station, similar to

the current station used by operators. Bausch & Lomb does not expect and is not requiring the

team to integrate the new process into any of its current manufacturing lines due to the

implications and complications of doing such. However, Bausch & Lomb is requiring that the

system be designed with integration and extensibility in mind.




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Bausch & Lomb Automated Lens Measurement System                                Project #05427


       To accomplish this goal, the team is requiring the system to meet the current shortest

cycle time of Bausch & Lomb’s manufacturing line with the intent to measure every lens.

Design of the standalone test station will be focused around the point of integration on the

manufacturing line. Design for manufacturing will be implemented in designing the system such

that as many common parts as possible will exist between the test station and the integrated

system.

       As required by Bausch & Lomb, a plan for line integration will be provided. The plan

will include all drawings, part numbers, instructions and bill of materials needed to integrate and

implement a fully functional system.



2.2.3 PLC Interface

       With lot integrity and line integration in mind, the system must be able to communicate

to a Programmable Logic Controller (PLC). A PLC interface will allow Bausch & Lomb to

record line data for process control, development and improvement.




2.2.4 User Interface

       On both the standalone test station and the proposed integrated solution a user interface is

required. This requirement will allow the test station operator to view and record the last

measurement made. On the integrated solution, a user interface will allow the line operator to

aide in monitoring the process. The user interface will also allow line technicians to easily set up

and calibrate the system.




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Bausch & Lomb Automated Lens Measurement System                                 Project #05427




2.2.5 Extensibility / Flexibility

       While it is impossible for Bausch & Lomb to know what the characteristics of future

products will be, it is requiring that the system be extensible and flexible enough to process these

new products. Possible influences could be the tint/opaqueness of the lens, the monomer used,

different molding materials and new lens geometry. It is impossible for the team to guarantee

this requirement can be satisfied indefinitely, but the team will focus on this requirement when

evaluating technologies. It is realistic that the team can satisfy this requirement within the

designed lifespan of the system.



2.3 Mission Statement

       With a high level view of the project in mind, the team agreed on the following mission

statement:

“To provide Bausch & Lomb with the most cost effective non contact solution for accurately

measuring the central thickness of a contact lens.”

       The team would like to focus on meeting the requirements with the most cost effective

solution possible. Certainly a low cost system may give up some of the flexibility desired by

Bausch & Lomb and a high-end system may satisfy and exceed all requirements. The team

would like to find the best overall solution, as expressed in the mission statement.



2.4 Goals & Objectives

       Besides meeting the requirements set forth by Bausch & Lomb, the team developed goals

and objectives to help provide them with the best overall solution.




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Bausch & Lomb Automated Lens Measurement System                                 Project #05427


       The first goal of the team was to research all non-contact methods for thickness

measurements. After researching various technologies, the team evaluated the pros and cons as

applicable to a make vs. buy solution within the given constraints.

       As stated in the mission statement, the system should be cost effective. This will allow

Bausch & Lomb to justifiably integrate the system into its manufacturing lines.

       The system, and more specifically the device used to measure the central thickness

should have customer support as needed. In the event that a solution with highly developed

components and/or software is implemented, the team wants Bausch & Lomb to have the best

resources possible for using the system.

       The team will also design any and all needed fixturing. As part of the design process and

project budget, the team will design as much of the system as reasonably possible.



2.5 Team Charter

       The team established guidelines on how to best conduct business in the most efficient

manner possible while promoting involvement from all team members. Team members are

expected to attend and be on time to all meetings or have a reasonable exception. Members will

be respectful of each other and of all ideas. Constructive criticism will be used at all times.

Meeting minutes will be emailed out by midnight of the next day. The next tentative meeting

will be announced at the end of each meeting.

       Assignments will be completed on time. In the event that an emergency arises or an

assignment cannot be completed on time, the group member will notify the team so that proper

arrangements can be made.




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Bausch & Lomb Automated Lens Measurement System                               Project #05427


       Emails will be responded to within 24 hours or by assigned date. Team members will

print out emails to aide in documenting the project. The team charter is a living document

subject to amendment upon ratification of all team members.



2.6 Constraints

       This project is faced with many constraints, which will influence the overall success of

the project. After doing some initial research, the team decided to perform a make vs. buy

rational analysis.

       In performing this analysis, the team came to the realization that the optimum solution

would be to integrate a developed technology into a system rather than attempt to reinvent the

wheel. This decision was influenced by many factors.

       The first limiting factors are the timeline, whereby the project needs to be finished by

early/mid May 2005 and the size/experience of the team. The team is neither large enough nor

proportioned correctly with its knowledge base to develop a non-contact solution accurate to the

micron range.

       Requirements set down by Bausch & Lomb leave a narrow margin of technologies

capable of performing the measurement. To develop a laser, spectrometer or ultrasonic

technology to a level of sophistication to meet Bausch & Lomb’s requirements is unrealistic.

       Furthermore, while patent searches did not reveal much prohibiting their use in the

contact lens thickness measurement application, there exists numerous patents around the

individual technologies themselves. This barrier alone would have greatly slowed down or

stopped the project, had the team opted to design a solution.




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Bausch & Lomb Automated Lens Measurement System                               Project #05427


        By deciding to integrate a purchased solution, the team has been and will continue to be

constrained by vendors. Before going into too much detail with vendors, confidentiality

agreements need to be established. This process has consumed approximately forty percent of

Senior Design I. This has impacted the project further do to the constraints on lead times for

sample reports. The ripple effect produced by this will delay final decisions as to which vendors

should be tested in house first. Delays in designing and ordering fixturing are also expected.

        Fixturing constraints exist due to the fine tolerances needed. Lenses will need to be

located with extreme accuracy and repeatability to meet requirements. As a result, a Bausch &

Lomb approved machine shop will be contracted to manufacture the fixturing designed by the

team.

        Bausch & Lomb has agreed to support the team with the process development personnel

and resources it has. Due to the number of projects and involvement in these, the team may be

constrained by the timing and amount of available support.

        While the team is sufficiently funded, budgetary constraints also exist. The team will

need to manage funds to be able purchase fixturing and pay for trial lease periods of systems.



2.7 Risk Assessment

        The requirements propose the greatest risk to the project. An initial bin of vendors was

quickly narrowed down because they did not feel they could perform. Due to the arrangement of

the senior design project and graduation of team members, there exists a hard deadline by which

all work must be completed. Any delays pose a risk to the entire project. This has lead the team

to pursue a very aggressive schedule in hopes of having time for a couple delays which will

surely occur. All lead times present a risk to the team. Future risks for the team include finding




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Bausch & Lomb Automated Lens Measurement System                               Project #05427


the most suitable vendor, being able to design and obtain fixturing for the system, producing a

fully functional test station and publishing an integration plan. The project is being worked on in

a parallel fashion whenever possible to mitigate the risk of missing deadlines.



2.8 Budget

       Bausch & Lomb is sufficiently funding the project to achieve success. With a well-

managed budget, the team will be able to purchase fixturing and bring systems in house on lease

or demo for full evaluation. The responsibility to allocate funding and purchase a complete

system will rest with Bausch & Lomb.




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Bausch & Lomb Automated Lens Measurement System                                 Project #05427



3.0 Concept Research


3.1 Possible Technologies and Discounted Technologies

          This section will outline the various concepts that have been researched.



3.1.1 Capacitance Method

          The capacitance method utilizes a parallel plate capacitor by inserting the material to be

measured between the plates to act as a dielectric.         The material will change the voltage

characteristics of the capacitor. As long as the material properties of the lens are known, a

correlation can be found between the voltage characteristics and the thickness of the lens. The

lens must be characterized with known thicknesses to create a look up table as a reference for the

device.



Advantages of the Capacitance Method:

    The accuracy of this method tends to be very high.

Disadvantages of the Capacitance Method:

    The operating distance of the plates may be too close to fit a curved material.
    The lenses must be characterized with known thicknesses. This may prove difficult
     without destroying the lens.
    The lens must be positioned exactly perpendicular to the plates of the capacitor.
    The plates of the capacitor must be fixed which would complicate the positioning of the
     lens.
    It would be impossible to measure the lens in the mold with this method.
    The effects of a curved material inside of a capacitor are unknown.




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Bausch & Lomb Automated Lens Measurement System                                Project #05427


3.1.2 Laser Triangulation

       The laser triangulation method uses a laser source oriented at an angle to the lens. The

laser both reflects off of the top surface and travels through to the bottom surface of the lens

where it is reflected for a second time. A laser sensor is situated opposite of the laser source.

This sensor is able to detect the reflection of the laser from both the top and bottom surface of

the lens. Data is passed to a software system that can measure the thickness of the lens based on

the refractive index of the material as well as the distance between the two laser signals.



Advantages of Laser Triangulation Method:

      Only one measurement of the lens is required.
      The accuracy of the systems is very high.
      Measurements can be done both in and out of mold.
      Sensor and receiver are very compact.
      Systems are relatively inexpensive.


Disadvantages of Laser Triangulation Method:

    May be difficult for laser to find surface of lens.
    Measurement time may be too long because of high accuracy.
    Refractive index may not be constant on some lenses.


3.1.3 Optical Spectrometer

       The optical spectrometer method uses a multi-chromatic light source oriented

perpendicular to the lens. The light source reflects off of the top surface and travels through to

the bottom surface of the lens where it is reflected for a second time. The reflected light is fed

into a spectrometer where the wavelengths of light are separated. Light bands of a certain

wavelength will appear that relate to the top and bottom surface reflection. The software system




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Bausch & Lomb Automated Lens Measurement System                              Project #05427


can measure the thickness of the lens based on the refractive index of the material as well as the

wavelengths that have been returned from the lens.



Advantages of Optical Spectrometer:

      Only one measurement of the lens is required.
      The accuracy of the systems is very high.
      Measurements can theoretically be done both in and out of mold.
      Sensor and receiver are very compact.
      Vendor is very confident based on past experience.


Disadvantages of Optical Spectrometer:

    May be difficult for Optical Spectrometer to find surface of lens.
    Characterization of angularity tolerance may be difficult


3.1.4 Laser (Autofocus)

       The autofocus laser method uses a laser and lens system similar to a DVD player in that it

measures the distance from the sensor to a reflective surface. The distance to the top surface is

subtracted from the distance to the bottom surface to obtain a thickness. This data must be

manipulated manually because neither the software nor the hardware was designed for thickness

measurements. These systems are also designed for highly reflective surfaces.



Advantages of Autofocus Laser:

    The accuracy of the systems is very high.
    Measurements can theoretically be done both in and out of mold.
    Sensor and receiver are very compact.


Disadvantages of Autofocus Laser:

    Reflectivity of lens may not be enough for sensor to find both top and bottom surfaces.
    Two measurements are required.



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Bausch & Lomb Automated Lens Measurement System                               Project #05427


    System not designed for thickness measurements.
    Z-axis movement of either lens or sensor may cause system to be outside of tolerance.
    Z-axis movement may drive up cost of system.


3.1.5 Ultrasonic

       The ultrasonic system is similar to a sonar system that uses a high frequency transducer

to map the position and surfaces of the lens. This system requires exact positioning of the lens in

a wet environment. The ultrasonic system that we are considering was designed and built with

contact lenses in mind, although it has never been used in an automated setting. The system is

being considered as a wet alternative to the dry systems.



Advantages of an Ultrasonic system:

    The accuracy of the systems is very high.
    System designed and built for contact lenses.


Disadvantages of an Ultrasonic system:

    Not currently used in an automated setting.
    Measurement required in a wet environment, which is not desired by Bausch & Lomb.
    Difficult to implement across all manufacturing platforms.
    High frequency transducer may drive up cost of system.




3.1.6 Vision System

       The vision system uses a high-resolution camera to take a digital picture of each lens.

The picture is then analyzed by a computer to determine the thickness of the lens based on the

number of pixels that the lens occupies. The accuracy of this system is dependant on the quality




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Bausch & Lomb Automated Lens Measurement System                                Project #05427


of the camera that is being used to photograph the lenses. This system is similar to the current

vision system.



Advantages of Vision System:

    Similar to current utilized technology.


Disadvantages of the Vision System:

      Software intensive system.
      Camera may not be able to see profile of lens.
      High quality camera may drive up cost of system.
      May be difficult to accurately photograph the lens while in the mold or mold half.
      The sensor (camera) may be large.


3.1.7 Mechanical Contact System

       The mechanical contact method involves automating the current procedure for measuring

the central thickness of the lens. Lowering a probe onto the lens that is resting on a pedestal does

this. The current procedure is done in the wet state on an offline manual station and is performed

by a technician. This system is used on an audit basis and the lenses must be destroyed after

being measured.



Advantages of mechanical contact system:

    The optical properties of the lens will not affect the system.

    The function and accuracy of this system are already known with respect to the manual

       station.

Disadvantages of mechanical contact system:

    Every lens cannot be tested because of quality issues.




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Bausch & Lomb Automated Lens Measurement System                                Project #05427


    Bausch & Lomb has specified a non-contact system.

    This method has not been attempted in the dry state.

    This method cannot be done in the mold or half mold.



3.2 Long List/Sources

       After the initial needs assessment, research was done to gather companies and

technologies that were available and could handle measuring the contact lens to Bausch &

Lomb’s specifications. Individual Internet research was completed and compiled. Several

sources were used such as Google, Thomas Registrar, Global Spec., and Bausch &Lomb

Experts. The companies that were discovered consists of: Lumetrics, Keyence, Elektrophysik,

FRT of America, Mission Peak Optics, Micro-Photonics, Filmetrics, Thermo Electron Corp.,

ABB, Adetech, Onosokki, MTI Instruments Inc., LMI Technologies, Micro-Epsilon, Beta Laser

Mike, ORYX, Panametrics, AccuSentry, Norman N. Axelrod and Associates, Dr. Schenk

Inspection Systems, Optical Data Associates, LLC., and Solve TECH Inc. The companies

offered a wide range of technologies that were discussed in section 3.1.




3.3 Short List

       Researched companies were contacted to obtain a technical representative to initially

assess if it was feasible for the company to handle the given application. In addition, to obtain

recommendations on which device(s) would be the best to use. After the initial screening the

long company list developed into the following short list:




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Bausch & Lomb Automated Lens Measurement System                                Project #05427


      Lumetrics (Low Coherence Intferometry)
      Mission Peak Optics (Optical Gauge)
      Filmetrics (Spectrometer)
      MTI Instruments (Fotonic Sensor/Triangulation Laser)
      LMI Technologies (Triangulation Laser)
      Micro-Epsilon (Spectrometer/Polychromatic White Light)
      ORYX (Optical Gauge)
      Panametrics (High Frequency Ultrasonics)


3.4 Reasons Not to Pursue Certain Companies

       The companies that did not make the short list had several reasons as to why they would

not be able to handle the application of measuring the central thickness of a contact lens.

       Beta Laser Mike had a device that consisted of a transmit and receive laser. The Focal

diameter would be too big for the application. This type of device is only good for flat

applications.

       FRT of America was not able to handle the application either. They were not confident

they could measure a curved surface such as a contact lens. Micro-Photonics could only measure

up to a maximum of 50 microns.

         SolveTech’s capacitive method would require a much larger spot size than required

(>1mm). Also, a fixture would need to be developed to position the lens accurately between two

plates with a separation distance significantly smaller than the overall height of the lens. The

method's accuracy was also questionable for the given application.

       Keyence’s device was incapable of measuring the size and accuracy needed.

AccuSentry’s technology is essentially a camera or vision system that is used to inspect products.

The entire concept of a vision system was discarded due to the current lack in adequate

technology. Norman N. Axelrod and Associates was not pursued any further because they do




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not sell a specific technology. Instead they would come in, analyze the problem, and custom

develop a solution. In this case, it would defeat the purpose of Senior Design.

        Dr. Schenk Inspection Systems sell products to measure thin films. Meaning, that all of

their products are meant to be installed on a high speed manufacturing line and take a

measurement based on the profile view of the thin film. Due to those characteristics this was not

a viable technology to pursue. Optical Data Associates, LLC is a small testing company that

specializes in high precision inspection of various components for their optical properties and so

forth. This company is just a testing firm and therefore would not be able to help or sell any

technology that would meet the needs of the application.

        Onosokki is only in the business of contact method systems for measurement and this

would not meet the applications requirement of a non-contact method requested by Bausch &

Lomb.

        Adtech, ABB and Thermoelectron were all companies researched, but no response was

ever heard from them. Therefore, they were not looked into any further.



3.5 Method for Gathering Technology and Company Information

        A teleconference or onsite visit was scheduled with each of the resulting companies. An

on-site visit to Lumetrics occurred on Tuesday (1/11/05). The remaining companies had

teleconferences with the team on Wednesday (1/12/05) and Friday (1/14/05). The information

gathered from each company was the device measurement range, measurement tolerance,

angularity tolerance, spot size, number of measurements required, device output, cycle time,

system cost, device model number, working height, lens state for measurement, sensor/controller

ratio, sample lead time, demo lead time, length of demo period, and system lead time. After all




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the information was collected each team member revised their notes and created a list of their top

company choices.



3.6 Patent Search

       Several patents were found that are within the realm of the given application. The topics

varied from a contact probe that measured the actual thickness of a contact lens, to automated

visual inspections of a contact lens. Since the application that is being dealt with is more process

oriented on the measurement of the central thickness of a contact lens, the patents listed below

are not being infringed upon by our application. Each will be discussed in further detail as to

why they do not impact our project. Please see Appendix A to view all patent abstracts for

further reference.

             4,665,624
             4,403,420
             5,205,076
             6,134,342
             6,765,661
             6,301,005
             6,490,028
             6,847,458
             6,822,745
             6,815,947
             6,791,691
             6,775,003
             6,791,696


3.6.1 Patent Information

       Patent number 4,665,624 deals with a soft contact lens analyzing apparatus. This

apparatus utilizes a fixturing device and several measurement scales to determine the diameter,

sagittal depth and central thickness of a contact lens. All of the scales use probes that must come




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into contact with the actual lens. Therefore this describes a mechanical, contact system which is

not what our application calls for.

          Patent number 4,403,420 is about a digital gauge for measuring the sagittal depth and

thickness of a lens, and the related systems and methods to do so. This method involves a fixture

and several linear encoders to measure the diameter, sagittal depth and central thickness of a

lens. Each of the encoders is connected to some type of probe that needs to come into contact

with the lens. Again, this is a mechanical contact system in which our application will not

infringe on.

          Patent number 6,134,342 talks about a visual inspection method and apparatus for a

contact lens. The method described is automated. The visual inspection system is looking for

defects such as foreign material, scratches, breakage and so forth. The actual system does not

perform any quantitative dimensional measurements and therefore does not have to do with our

application.

          Patent number 5,206,076 is for a self aligned manufacturing system and method. This

method does not pertain to the metrology of contact lenses. It describes a method on how to

actually produce contact and intra-ocular lenses. Since this is describing the manufacturing

process and not a measurement process our application does not conflict.

          Patent number 6,765,661 describes a lens (such as contact lens) inspection method. This

system looks for such flaws as tears or surface defects. Again, this system does not perform any

quantitative dimensional measurements and therefore our application will not infringe with this

patent.

          Patent number 6,301,005 deals with an inspection system for optical components. This

system contains a device to hold the optical component in place. Also, it has the means to




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inspect the optical component for any apparent defects. Given that this system does not take into

account quantitative dimensional measurements the compared application is not the same and

will not infringe.

        Patent number 6,490,028 is for a variable pitch grating diffraction range finding system.

What is described is a very precise method to determine the range or distance from a reference

point to an object. Utilizing a variable pitch grating achieves this high precision. This system

uses a completely different methodology than any of the apparatuses the team has evaluated for

the given application.

        Patent number 6,847,458 refers to a method and apparatus for measuring the shape and

thickness variation of polished opaque plates. In this system dual interferometers are used. One

is placed on each side of the plate to perform its surface mapping and other calculations. Since

the system is attempting to measure opaque plates two interferometers must be used. This

system is different from any of the researched systems that have been evaluated because it is a

dual interferometer system. All of the systems researched use only one interferometer. Also,

this is for measuring opaque substances, as our application is to measure optically clear lenses.

        Patent number 6,822,745 talks about optical systems for measuring form and geometric

dimensions of precision engineered parts. This patent does describe a similar technology that we

will be utilizing. However, it describes the specific equipment and not the overall process of the

measurement. Whichever piece of equipment is chosen to be used in our application should be

protected by that respective company’s patent. No process issues are present that would violate

this patent.

        Patent number 6,815,947 deals with a method and system for thickness measurements of

thin conductive layers. This system utilizes an electrically conductive method known as eddy




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current. Extremely thin films that also have conductive properties are the only applicable item

that may be measured using this system. Due to its limitations, the team ruled out this

technology initially. None of the systems being evaluated use this or any related technology.

       Patent number 6,791,691 refers to a measuring method that uses attenuation in total

reflection. This patent describes a similar technology that we will be utilizing. Furthermore, it

describes the specific equipment and not the overall process of measuring the object. That

respective companies patent should protect whichever piece of equipment the team decides to

use in our application. No process issues are present.

       Patent number 6,775,003 is about an apparatus and method for total internal reflection

spectroscopy. This also describes a similar technology that is being evaluated. Again, although

it has a similar technology it does not describe the process. Therefore, the researched

technologies respective companies patent should protect the equipment in the end that the team

decides to put into use. No process issues are present.

       Patent number 6,791,696 talks about an automated optical measurement apparatus and

method. This patent describes the method to measure lens properties, such as central thickness,

utilizing a wave front analysis. None of the technologies researched involve this type of

technology. For this reason, our application will not infringe on this patent.



3.7 Product Specification Research

       This section highlights how the characteristics of a contact lens were researched and

captured.




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3.7.1 Contact Lens Quick Reference Guide

       Research was completed to create a reference guide for Bausch & Lomb’s contact lens

specifications. The specifications include product line, lens type, monomer, diameter and

tolerance of the lenses, wet central thickness range and tolerance of the lenses, sagittal depth

range and tolerance of the lenses, power range of each lens, refractive index of each lens, if the

lens had tint, and the document number of the Finished Product (FP) specification. This guide

was referred to when vendors were contacted. Due to proprietary information this chart cannot

be appended.




3.7.2 Radius of curvature

       During research the radius of curvature (base curve) was questioned by some of the

vendors as this could potentially pose a problem in obtaining the central thickness measurement.

This is another area where experts at Bausch & Lomb were able to inform the team of the

dimension. This dimension varies across all product lines. Due to proprietary information this

dimensional information cannot be released.



3.7.3 Mold Information

       During the early stages of the project the mold material was introduced as Polypropylene

and PVC depending on which contact lens it will contain. The theoretical refractive index of the

materials are known, however the actual refractive index of the molds is unknown. This is

confidential information that cannot be disclosed.




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3.7.4 Cost Research

       Research was done to identify what the overall cost is to actually manufacture a contact

lens. Cost was broken down by each stage of the lens manufacturing process. Also, the cost of

material and operator labor and benefits were gathered. If the apparatus was eventually

integrated into the line as an automated system, in order to cost justify the equipment, such costs

would need to be known. This material will be covered further in section 6.0.



3.7.5 Centration of Lens

       In order to properly present the lens to the sensor, and to take the various lens profiles

into account, a centration requirement was determined. If the measurement spot size is less than

50 microns in diameter, than the measurement must be offset at a distance from center equal to

spot diameter plus 10 microns, in both the x and y directions. If the spot size is larger than 50

microns in diameter, the measurement can be taken directly in the center of the lens, at a distance

of +/- 500 microns in either the x or y direction.




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4.0 Feasibility

       This section outlines how the team determined the feasibility of the companies, and their

respective technologies.


4.1 The Short List Revisited

       Once the companies were eliminated due to their inability to meet the requirements of the

project, the team was left with eight companies to evaluate. Again, these companies were:

                      Lumetrics
                      Panametrics – NDT
                      MTI
                      ORYX
                      Mission Peak Optics
                      Micro-Epsilon
                      LMI
                      Filmetrics

       All of these companies seemed capable of meeting the project requirements. The team

also had a good feel for the true potential of each company. After such extensive research and

learning from various technology experts, the team had a solid understanding of the technical

details to make effective decisions. With this knowledge, the team had an idea of the top three

companies that should be evaluated, but that idea needed to be confirmed with evidence.

Constructing a Feasibility Matrix did this. Please see Appendix B for the complete matrix.




4.2 Judging Criteria




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        The criteria by which the remaining companies would be evaluated were determined by

the project requirements (Appendix C). The primary technical criterion was determined, but

there was additional information the team felt was important that should be included. While this

data would not be scored, it was still listed on the Feasibility Matrix for reference and to keep in

mind when evaluating the companies. The criterion is listed below:

Technical Criteria (Scored)                           Informational Criteria (Not Scored)

     Measurement Range                                     Device Model Number

     Measurement Tolerance                                 Working Height

     Angularity Tolerance                                  Lens State for Measurement

     Spot Size                                             Sensor/Controller Ratio

     Number of Measurements Required                       Sample Lead Time

     Device Output                                         Demo Lead Time

     Cycle Time                                            Length of Demo Period

     System Cost                                           System Lead Time

     Team Opinion

Table 1.0 Technical and Informational Criteria for the Feasibility Matrix




4.3 Weighting Criteria

        Once the technical criterion that the companies would be evaluated for was identified, it

was necessary to weight the criteria. The criterion must be weighted because some are more

important than others. The most important criterion would have a weight of five, and the least

important criterion would have a weight of one. No criteria were given a weight of one, and the

majority had a weight of five. The reason for this is that there are multiple critical factors that




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the systems must be able to meet in order to work effectively. The criterion that was slightly less

important was given weights of four and three.



4.4 Scoring

    Once the companies, criterion, and weight were all identified the scoring could begin. This

was done with a fairly simple system outlined below:

     Companies received a score of 1 if they might be close to meeting the requirements, but it
      would require some additional engineering to get the system to be able to achieve that
      specific criterion.
     Companies received a score of 2 if they met the requirements.
     Companies received a score of 3 if they exceeded the requirements.


Two examples of the scoring system are outlined below:

             System Cost Scoring                                  Device Output Scoring

If the system cost more than $10,000, the             If the system had an analog output, the

company received a 1.                                 company received a 1.

If the system cost $10,000, the company               If the system had a digital output, the

received a 2.                                         company received a 2.

If the system cost less than $10,000, the             If the system had a digital output and some

company received a 3.                                 type of software bundle, the company

                                                      received a 3.

Table 2.0 Technical and Informational Criteria for the Feasibility Matrix




        These scores were then multiplied by the respective criterion weight and summed to find

the overall score for each company. The top three scores then identified the best three

companies and technologies that are able to successfully meet the projects needs.



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4.5 Sample Test Results

       Samples of contact lenses in three different states were sent to all vendors to evaluate.

The rationale was that this would once again confirm the teams’ decisions and insure that all of

the decisions being made were sound. Please note that LMI would not evaluate samples, so there

is no report from them. Please also note that all vendors (except Panametrics – NDT) were given

contact lenses still sealed in the mold, contact lenses in the mold but decapped and dry contact

lenses. Panametrics – NDT was given wet contact lenses in solution to evaluate. Below is a

summary of the testing results from each vendor. The full reports can be found in Appendix D.




Lumetrics

       Lumetrics conducted a sample analysis of the contact lens in various states and evaluated

the systems ability to accurately and repeatedly measure the center thickness. Since they could

measure the lens in the wet state, in addition to dry, it is easy to compare the results they provide

to the results acquired from the same lens using the current manual process. For all trials

conducted, their results had excellent agreement with the current process.



MTI

       The technology utilized by MTI is only able to measure the lens in the dry state. The

team has not received an official report from them, but has conversed with their representative on

multiple occasions. The general consensus so far seems to be that they are not able to achieve




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repeatable results with any of their systems. They are however continuing their attempts and the

team is moving forward while awaiting the data from them.



ORYX

       The team has not received an official report from ORYX. The preliminary results given

via e-mail and phone calls show that they are able to measure the lens in any of the various dry

states. The only issue that they may have is the cycle time requirement, since their sensor takes

longer than any other to acquire the returned signal and calculate the thickness. The team feels

comfortable with what ORYX is capable of and is awaiting their final report.



Panametrics – NDT

       Panametrics measures the lens in the wet state only due to their ultrasonic technology.

Therefore, it is very easy for the team to confirm their results and see how well they relate to the

current process. All of the results show excellent agreeability with the current process. All

measurements from Panametrics were verified to be within two microns when the same lens was

measured with the current manual station.



Micro-Epsilon

       The team does not have an official test report from Micro-Epsilon, but the vendor has

come and performed a demonstration. This demonstration showed their technology and how it

works, and they were able to accurately measure several lenses in the various dry states. These

initial demonstration measurements show good compatibility with results acquired from the

current process.




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Mission Peak Optics

       Mission Peak Optics was only able to measure the dry lens in its free state. Their report

was quickly returned to the team within one day of receiving the samples. The results from their

testing look promising and have good agreement when compared to the current process.



4.6 The Top Three

       The top three companies identified by the matrix confirmed the teams’ opinion on what

the best companies were. The three companies are:

                    Lumetrics

                    Micro-Epsilon

                    Panametrics

These three companies will have their units brought in house to Bausch & Lomb for the team to

do extensive testing on the units. The team will determine these units’ abilities to meet the

projects needs and will make a final recommendation to Bausch & Lomb from these companies.

5.0 Designs

       This section outlines the designs of the vendors, as well as our preliminary design and

placement plan. Additional information from each company’s website can be found in Appendix

E.

5.1 Lumetrics




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         The DI 330 OPTIGAUGE FILM THICKNESS MEASUREMENT SYSTEM employs

advanced optical technology originally developed by Eastman Kodak to monitor its polyester

film manufacturing operation for thickness uniformity. The DI 330 system operates using the

principle that light incident on a translucent film will reflect a portion of that light. In fact, a

reflection will occur at every surface interface. So, a single-layer film will have two reflections,

one from the upper surface (R1) and one from the lower

surface (R2). A two-layer film with an adhesive in-between

will have four reflections; one from the upper surface (R1),

one from the first layer-adhesive interface (R2), one from

the second layer-adhesive interface (R3), and finally one

from the lower surface (R4).

    The different reflections carry information about layer

thickness based upon the distance that the reflections have

traveled. Using advanced digital processing and proprietary

software, the DI 330 OPTIGAUGE system analyzes each

reflection and then calculates the exact thickness of each

layer.
                                                                     Figure 2.0 Light Reflections bounced back to
    Features of DI 330 OPTIGAUGE                                     the DI 330 OPTIGAUGE for a single-layer
                                                                     film and a two-layer film with adhesive.
          Reduce maintenance expenses with unique
              optical technology that is non-toxic, and non-radioactive.
          Decrease inspection costs and scrap with non-contact, non-destructive gauging
              system
          Improve customer satisfaction and profits through the highest guaranteed accuracy of
              ± 0.1 micron (± 0.004 mil)
          Decrease scrap costs with instantaneous feedback and a measurement rate of 30 Hz
          Lower inspection costs with a wide range of measurement from 12 microns to 9 mm
          Decrease inspection time with simultaneous measurement of multiple layers




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        Flexible system measures specialty multi-layer films, medical packaging, adhesives
            and laminates
        Portable enough to inspect and measure lenses, flats, assemblies, ball lenses with no
            system changes
        Works with a multitude of solids, liquids and coatings


       The DI 330 OPTIGAUGE seems to be the most versatile sensor of our final three. It is

able to measure with both halves still on the lens, as well as with the bottom half of the mold still

attached to the lens, and the freestanding lens. Of course we would like to place the sensor as far

up the line as we can. The optimum place for this sensor would be immediately after the

monomer that makes up the lens has set into its solid form. This takes place after the lens has

gone through an Ultraviolet (UV) curing process.




                        Figure 2.1 - Casting Machine: The lenses
                        exit the UV curing stage of the casting
                        machine and are in their solid state for the
                        first time.




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       The lenses are placed in a single file on a conveyer after the UV cure process. This

position in the line would allow the sensor to measure before the top of the mold has been

removed. The size of the sensor should not be a problem if it is placed before the machine that

removes the top of the mold.



5.2 Micro-Epsilon

       optoNCDT 2400 is a confocal displacement sensor for extremely precise applications.

Polychromatic light (white light) is focused onto the target surface by a multi-lens optical

system. The lenses are arranged such that the light is broken down into monochromatic spectra

by controlled chromatic deviation. A certain distance is assigned to each wavelength by a factory

calibration. The light reflected from the target surface is passed via an optical arrangement to the

receiver optical system, which detects and processes the spectral changes.




               Figure 3.0 optoNCDT 2400: In-Focus Displacement and Position Measurement

Characteristics

Measuring principle: Confocal
Measuring range: 0.08/0,35/1/3/10/24 mm
0.003/0.014/0.039/0.118/0.39/0.94 inch
Linearity: ±0.1 % FSO (full scale output)
Resolution: 0.004 % FSO
Measuring rate (selectable): 30/10/300/1000 Hz


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Applications




Figure 3.1 Thickness of transparent materials




Figure 3.2 Distances to glossy and transparent surfaces




Figure 3.3 Measurements in holes (hole depth)




Figure 3.4 Measurement of surface contours



    After speaking with a representative of the company, and from the data that has been

returned to us from the testing procedure, the team has decided that there are two logical

places for the sensor.



     After the top of the mold has been removed.

     After the lens has been released completely from the mold


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                      Figure 3.5 Lens Release Machine: This machine
                      removes the lens from the bottom half of the mold.




       The optical sensor for the optoNCDT 2400 is very compact and could be

positioned in the 4-6 inch space before the mold release machine. The data collection

box can be positioned at the bottom of the machine where there is more room.




                      Figure3.6 Lens Release Machine: The lenses pass
                      through this section of the machine without any
                      pieces of the mold before they are placed in the tray
                      at the far end of the picture.




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        It would be more desirable to take the measurement while the lens is still in the

bottom mold half (for centering purposes). If it is found that the optoNCDT 2400 can

take more accurate measurements while the lens is completely free of the mold, then the

sensor will be implemented on one of the lens handling spindles. The picture above

shows a machine that is not surrounded by close quarters creating a good location for the

sensor and data acquisition box. This is the last place in the lens release machine that the

lenses are being processed on an individual basis. After this they are placed on the tray

shown in the picture until they are packaged.

        The positioning of the lens may cause some design issues if the lens has already

been released from the mold. The mold would be easier to center and would also be

further up the line.


5.3 Panametrics

    r
                                                  Panametrics-NDT 25 MULTI PLUS

                                                  ultrasonic thickness gage for multilayer

                                                  materials offers several unique

                                                  measurement capabilities. In addition to

                                                  making thickness measurements on metal,

                                                  plastic and many other materials with

                                                  varying thickness ranges, the 25 MULTI

                                                  PLUS can calculate and simultaneously
        Figure 4.0 Panemetrics-NDT 25
        MULTI PLUS                                display as many as four separate




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measurements. The Summation Mode accurately displays the total thickness of selected

layers.

Features of the 25 MULTI PLUS:

           Calculates and simultaneously displays thickness measurements of as many as

             four layers, and displays the total thickness of selected layers

           Measures thickness of barrier layers in applications such as plastic fuel tanks

             and bottle pre-form

           A-Scan display for waveform verification

           Wide thickness range: 0.004 to 20 in (0.100 to 508 mm)

           Resolution up to 0.0001 in (0.001 mm)

           Internal alphanumeric file-based datalogger stores 18,000 thicknesses or 1,750

             waveforms



          The Barrier Layer Mode feature makes it possible to measure critical barrier

layers in multilayer plastic parts such as gas fuel tanks and bottle pre-forms. This special

mode displays the thickness of thin barrier layers that are typically too difficult to

measure with conventional ultrasonic thickness gages. This is because of lack of

separation between the echo from the front and back of the barrier layer.

          The Panametrics sensors would require that the lens be in the wet state. While

this is not the most desirable state to measure the lens in, it may be an acceptable

alternative to the dry methods discussed in previous sections. Panametrics has disclosed

that the 25 MULTI PLUS has been used before for measuring of contact lenses in a non-

automated environment and is a proven technology for our application. Unfortunately,




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there may be a problem with measuring lenses that are less than one hundred microns

thick as that is the lower limit that the device can theoretically measure. This problem

could be remedied with a higher frequency transducer. This high frequency transducer

may raise the cost of the system significantly.

       Precise positioning of the lens in a wet environment would require the design of a

wet cell. Positioning inside the wet cell may also increase our cycle time. This system

would also severely limit the possible placement of the sensor on the line. The desire to

measure the lens in the dry state further up the production line is driven heavily by the

logistics of manipulating a lens in the wet state. The cost savings of doing this

measurement in the dry state in relation to the wet state is relatively small.




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6.0 Conclusion

       This section will wrap up the outcome of Senior Design I, and outline the goals of

Senior Design II.



6.1 Summary

       Senior Design I has focused mainly on researching technologies and devices

available. The team started with 22 companies, and narrowed the list down to 8

companies. After performing a feasibility assessment, the team was able to separate its

top three choices. With these top vendors the team plans to go on to Senior Design II and

accomplish all its goals.



6.2 Goals for Senior Design II

       The final goal for Senior Design II is to present to Bausch & Lomb the teams

compiled in-house test data and final recommendations of the top units. Once the final

unit is chosen, the team plans to create a fully functional offline system. The team will

also develop an implementation plan, for Bausch & Lomb to integrate the system online.



6.3 Action Plan to Achieve Goals

       The scheduling of the following action items is outlined in Appendix F. To

accomplish these goals the action plan is to start by bringing in demonstration units from

the top vendors. The team will perform a DOE and a Gauge R&R on each device to

determine if the device will meet Bausch & Lomb’s standards.



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           The team plans to do a full cost benefit analysis. From preliminary calculations,

it is anticipated that all 8 of the devices from the feasibility matrix will prove to be cost

effective.

           With drawings from the top three vendor units, the team plans to start designing

fixtures needed to secure the unit, as well as fixtures to correctly orient the contact lens.

           From testing, the cost analysis, and all the data gathered from Senior Design I, the

team will present to Bausch & Lomb their final recommendations on each device. Once

the final system has been chosen, the team will work on creating a fully functional offline

station.

           The various product lines at Bausch & Lomb will be thoroughly evaluated, and an

implementation plan will be developed to integrate a system onto the line chosen by

Bausch & Lomb. The plan will include where the device should be positioned on the

line, and how and where contact lenses that failed will be discarded. As well as how the

device will be connected to the existing PLC interface.




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Bausch & Lomb Automated Lens Measurement System                               Project #05427




7.0 References

    This section gives the citation for the sources of information utilized while compiling

this report.



Global Spec 16 Jan 2005 <http://www.globalspec.com/>

Google 16 Jan. 2005 <http://www.google.com/>

Lumetrics 12 Feb. 2005 < http://lumetrics.net/>

Micro-Epsilon 12 Feb. 2005 <http://www.micro-epsilon.com/index_en.html>

Micro Format Inc. 10 Feb. 2005 <http://www.paper-paper.com/weight.html>

Mission Peak Optics 12 Feb. 2005 <http://www.missionpeakoptics.com/>

The World of Hair 10 Feb. 2005
<http://www.pg.com/science/haircare/hair_twh_141.htm>

Thomas Register 16 Jan 2005 <http://www.thomasregister.com/>

United States Patent and Trademark Office 14 Jan. 2005
<http://www.uspto.gov/patft/index.html>




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Bausch & Lomb Automated Lens Measurement System              Project #05427



8.0 Appendix


             Document                             Appendix
Patent Abstracts                                     A
Feasibility Matrix                                   B
Project Requirements                                 C
Vendor Testing Reports                               D
Vendor Website Literature                            E
Timeline for Senior Design II                        F




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Bausch & Lomb Automated Lens Measurement System   Project #05427



Appendix A – Patent Abstracts




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Bausch & Lomb Automated Lens Measurement System   Project #05427



Appendix B – Feasibility Matrix




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Bausch & Lomb Automated Lens Measurement System   Project #05427



Appendix C – Project Requirements




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Bausch & Lomb Automated Lens Measurement System   Project #05427



Appendix D – Vendor Testing Reports




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Bausch & Lomb Automated Lens Measurement System   Project #05427



Appendix E – Vendor Website Literature




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Bausch & Lomb Automated Lens Measurement System   Project #05427



Appendix F – Timeline for Senior Design II




                                             53     2/18/2005

				
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