Optical Image Processing Division C-DIT
Details of the Conferences
Sl. No Event Title of the Paper
Optics East 2004. Study of Stress Distribution at the footprint of
tyres by applying Holographic Interferometry.
1 Venue :
SPIE-USA Performance Analysis and Material Dependence of
Asia- Pacific Micro Holographic Optical Elements as Couplers
2 Optical for Fiber Optic Communication
Abstract of the accepted papers
1. Study of Stress Distribution at the footprint of tyres by applying
Ajith Kumar P.T, Prasannan, Sajan Ambadiyil, Varghese Kuruvilla*
Optical Image processing Division, Center for development of Imaging technology,
Thiruvallam, Thiruvananthapuram – 27.
*Department of Physics, Cochin University of Science and Technology, Cochin –
682022, Kerala, India.
The performance of any tyre design depends very much on the distribution of stress
at its footprint. Holographic interferometry techniques are being used for the non-
destructive evaluation of tyres. However this technique cannot be directly applied for
the mapping of stress at the footprint of tyres. This is because of the fact that the
footprint is obscured in between the tyre and the supporting surface. This paper
describes about the experimental method we have adopted for the mapping of stress
at the footprint of tyres. Both double-exposed and real-time holographic
interferometric techniques were used. Holograms of good fringe visibility were
recorded. This technique can be effectively applied for the evaluation of prototype
tyre designs and for the identification of optimum designs and material compositions.
Stress Distribution Study in Tyres - Holographic Non-Destructive Testing
Optical Image Processing Division
The technical input and support from the R&D center, CEAT Tyre manufacturer is
2. Performance Analysis and Material Dependence of Micro
Holographic Optical Elements as Couplers for Fiber Optic
Ajith kumar P.T, Sajan Ambadiyil, Prasanan.G, Jithesh sathyan*,
Optical Image processing Division, Center for development of Imaging technology,Thiruvallam,
Thiruvanathapuram – 27.
* Jithesh Sathyan, Infosys-Nortel ( GEM Design ), Bangalore.
* *NeST Research and Development Center, Kakkanadu, Cochin.
Holographic Optical Elements (HOEs) are attracting in Optical fiber communication and optical
information processing systems. Since HOEs have multiple function capability and wavelength
selectivity, they are especially suitable for a verity of functions in intelligent optical networks.
Other advantages of HOEs are design flexibility and ease of replication. In contrast to
conventional HOEs, Optional communication and information systems need smaller and efficient
elements of desired characteristics and transfer functions. Such Micro Holographic Optical
Elements(MHOEs) can either be an HOE, recorded with two narrow beams of laser light or a
segment cut from a larger HOE, recorded in the conventional manner. However the recording
parameters and hence the diffraction efficiencies and transfer functions of MHOEs and
Segmented HOEs (SHOEs) vary from one another.
MHOEs include holographic couplers, splitters gratings, filters and interconnects. In our study,
micro holographic couplers and segmented holographic couplers, having specific focusing and
diffraction characteristics, were recorded in different holographic recording media such as silver
halide(Geola PFG and PFG ), dichromated gelatin (Geola PFG) and photoresist(Shipley’s
1800). The MHOEs and SHOEs were shot in each medium, with the same angle between the
object and the reference beam. Also they were recorded with the same focal length. Initially the
elements were tested at 633nm from a HE-Ne laser and at 442nm from a He-Cd laser. It was
found that the diffraction efficiency of the MHOE was higher than that of corresponding SHOE.
Coupling factor, isolation and insertion loss of the elements differed as the recording medium was
changed. The study was repeated at various other wavelengths of practical relevance and
diffraction efficiency, coupling factor, isolation and insertion loss of the elements were measured.
The paper reports in details about the above result and related design considerations.