Now showing items 1-4 of 4

  • A circular harmonic quantized amplitude compensated matched filter 

    Zhang, H.; Wang, Z. Q.; Cartwright, Colin M.; Ding, M. S.; Cook, N. J.; Gillespie, W. A. (Elsevier, 1998)
    The circular harmonic expansion technique has been applied to the quantized amplitude-compensated matched filter for rotation-invariant recognition. The filter is an amplitude filter with three discrete grey levels. The ...
  • Effects of optical bias on moving gratings in bismuth silicon oxide at large fringe modulation 

    Wang, Z. Q.; Cartwright, Colin M.; Gillespie, W. A.; Cook, N. J. (Optical Society of America, 1996)
    Optical bias has been applied in the formation of moving gratings in bismuth silicon oxide at large fringe modulations. It is shown that optical bias is an effective method of overcoming the problems associated with the ...
  • Experimental implementation of a photorefractive joint transform correlator with circular harmonic filters 

    Zhang, H.; Cartwright, Colin M.; Ding, M. S.; Wang, Z. Q.; Cook, N. J.; Gillespie, W. A. (Elsevier, 2000)
    We present an experimental realization of optical correlation for real-time rotational-invariance pattern recognition by means of a photorefractive joint transform correlator. Single and multiple circular harmonic components ...
  • Implementation of a photorefractive binary joint transform correlator 

    Cook, N. J.; Carnicer, A.; Vallmitjana, S.; Juvells, I.; Cartwright, Colin M.; Gillespie, W. A. (Optical Society of America, 1998)
    The use of photorefractive materials such as Bi 12 SiO 20 as dynamic holographic media is becoming an interesting alternative to that of the current liquid-crystal-based modulators in real-time optical image processing. ...