Page 170 - Introduction to Information Optics

Exercises

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H(p,q)

Fig. 2.68.

2.17 With reference to the JTP of Fig. 2.18, if the input object is imbedded in
an additive white Gaussian noise with zero means; that is /(x, y) + n(x, v),
show that the JTC is an optimum correlator.
2.18 Consider the microcomputer-based FDP of Fig. 2.17. Assume that the
operation speed is mostly limited by the addressing time of the SLMs and
the response time of the CCD array detector. If the addressing time of the
SLMs is 60 frames/sec and the response time of the CCD detector array
is 50 frames/sec, calculate the operation speed of the processor.
2.19 Refer to the hybrid FDP and the JTP of Figs. 2.17 and 2.18, respectively.
(a) State the basic advantages and disadvantages of these two processors.
(b) What would be their required spatial carrier frequencies?
(c) What would be their input spatial coherence requirements?
2.20 Suppose that the addressing time of the SLMs and the response time of
the CCDs are given by 1/60 sec and 1/50 sec, respectively.
(a) Calculate the operating speeds for the JTC and the single SLM JTC,
respectively.
(b) Comment on your results with respect to the one you obtained for
the FDP in Exercise 2.18.
2
2.21 Suppose the size SLM is given as 4 x 4cm . If the spatial-frequency
bandwidth of the signal is 10 lines/mm, the focal length of the transform
lens is 500 mm, and the wavelength of the light source is 600 nrn,
(a) Compute the optimum number of joint transform power spectra that
can be replicated within the device's panel.
(b) Assume that the replicated JTPs are illuminated by temporal coher-
ent but spatially partial-coherent light. What would be the spatial
coherence requirement of the source?
(c) Show that the signal-to-noise ratio of the correlation peak improved
by using spatially partial-coherent illumination.