Page 167 - Introduction to Information Optics

2. Signal Processing with Optics

Ri

R2

Rl<R 2
Fig. 2.63.

2.11 Assume that an optical processor is illuminated by a monochromatic
plane wave, as shown in Fig. 2.64, where the amplitude transmittance of
the transparency is denoted by /(c, r\), and I < f.
(a) Calculate the output complex light field at the back focal length of
the transform lens.
(b) Determine the output irradiance.
(c) What is the effective focal length of this Fourier transform system?
(d) Show that the scale of the Fourier spectrum is proportional to the
effective focal length.
2.12, Assume that the amplitude transmittance of an object function is given by

cos(p 0x)],

where p 0 is an arbitrary angular carrier spatial frequency, and f(x, y) is

Fig. 2.64.