Photonics Dictionary: C

An analog signal capable of being modulated as to frequency, amplitude or phase to carry information.

The ratio of the power of the carrier wave to that of unwanted signal distortions, or noise, before any nonlinear signal processing such as detection or amplitude limiting.

The amplitude modulation through the application of modulating voltage to the cathode circuit.

A light beam whose electric vectors can be broken into two perpendicular elements that have equal amplitudes and that differ in phase by l/4 wavelength.

A closed-loop system that compensates for thermal blooming by optimizing only one parameter: the amplitude of the phase correction.

A fiber optic communications system that works on the principles of homodyning or heterodyning. The transmitting laser produces an optical wave that is modulated in amplitude, phase or frequency by...

A deliberately nonlinear amplitude modulation that strengthens weak signals and reduces strong signals for transmission.

The use of computer analysis in the calculation of diffraction patterns for information on the design of optical systems. In this method, the electric field amplitude and phase in the aperture are...

A computer-generated hologram (CGH) is a holographic image produced using computational methods and algorithms, rather than traditional optical techniques. CGHs are generated entirely in digital form...

Continuous wave (CW) refers to a type of signal or transmission where the signal is constant and does not vary with time. In various contexts, the term is used to describe continuous, uninterrupted...

One area of image enhancement, accomplished by spatial filtering schemes, that usually involves attenuation of phase changes in the complex amplitude over a limited region of the Fourier spectrum of...