Page 87 - Introduction to Information Optics

2. Signal Processing with Optics

Fig, 2.4. The Michelson interferometer. BS; beam splitter; M, mirrors; P, observation screen.

split, is given by

Ar = Ate (2.6)
Aii'
where the temporal coherent length of the source is

1
t (2.7)
~ Ay'
In fact, the coherent length of the source can also be shown as
A 2
Ar (2.8)
AA'
where X is the center wavelength, and AA is the spectral bandwidth of the light
source.

2.2. PROCESSING UNDER COHERENT AND
INCOHERENT ILLUMINATION

Let a hypothetical optical processing system be shown in Fig. 2.5. Assume
that the light emitted by the source Z is monochromatic, and let u(x, y) be the
complex light distribution at the input signal plane due to an incremental
J
source dZ. If the complex amplitude transmittance of the input plane is /(x, > ),