Pitch Polishing of Semiconductor Optical Materials Using Continuous Iterative Interferrogram Analysis

  • Neeraj Pandey
  • K. K. Pant
  • S. Mishra
  • L. M. Pant
  • A. Ghosh
Conference paper
Part of the Environmental Science and Engineering book series (ESE)

Abstract

Semiconductor optical materials including Germanium, Silicon, ZnS and ZnSe are widely used to fabricate high precision optical components for focusing infrared radiation to the detector of thermal imaging system. For better performance of thermal imager, the quality of optical components in terms of surface accuracy, surface quality and other fabrication parameters must meet tighter tolerances. In the present work, we report a conventional pitch polishing technique using continuous slurry polishing to maintain surface accuracy of the order of sub micron accuracy and surface quality as per MIL-O-13830A. A phase shift laser interferometer with wavelength 632.8 nm is used as in-process measurement of surface accuracy. The hardness and viscosity of pitch, slurry concentration, polishing pressure and pitch lap compliance has been monitored and optimized for optimum polishing time and best results. During polishing, surface wedge was also monitored and controlled within 30 s of an arc.

Keywords

Infrared materials Optical components Electro-optics Optoelectronics 

Notes

Acknowledgments

Authors are thankful to Dr. A. K. Gupta, Director, IRDE for his support and encouragement for the work. We are also thankful to Dr. S.S. Negi, Scientist ‘H’ for his valuable suggestions.

References

  1. 1.
    J. B. Arnold, ‘Machinability studies of infrared window materials and metals,’ Proc. SPIE 93, 96-103 (1976).Google Scholar
  2. 2.
    Twyman F., ‘Prism and Lens making’, 2nd ed., London, Hilger and Watts, 1952.Google Scholar
  3. 3.
    H. H. Karow, Fabrication methods for precision optics, John Wiley and Sons Inc, New York, (1993).Google Scholar
  4. 4.
    Robert E. Parks, ‘Fabrication of Infrared Optics’, Optical Engineering, March 1994/Vol. 33 No. 3/685-691.Google Scholar

Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Neeraj Pandey
    • 1
  • K. K. Pant
    • 1
  • S. Mishra
    • 1
  • L. M. Pant
    • 1
  • A. Ghosh
    • 1
  1. 1.Instruments Research and Development EstablishmentDehradunIndia

Personalised recommendations