Photonics Dictionary: P

A method used to approximate the values of the homogeneous second derivatives at each iteration in the course of lens design and that excels the rate of convergence of the damped least squares method...

In image processing, generating a color image from monochrome data by assigning a color to each of the gray levels.

Coded image obtained optically with a nonredundant pinhole array imaging aperture.

An image that is reversed contour or inside-out.

A method of coding information in a communications system where the shift in the phase of an electromagnetic wave represents a particular bit or character.

The point spread function (PSF) is a fundamental concept in imaging that describes the response of an imaging system to a point source or point object. It characterizes how a single point of light is...

A filtering method that restores a blurred image by setting its power spectrum equal to that of the original image.

In a semiconductor, the state created by the addition of a dopant that creates excess holes.

A semiconductor material in which the dopants create holes as the majority charge carrier. It is formed by doping with acceptor atoms.

The finite amount of electrical charge generated in response to incident radiation and transferred from one storage element to the next in a charge-coupled device. Each packet corresponds to a pixel...

The transmission of data in groups (packets) of information~comma~ each handled as an aggregate.

1. In a photonic interconnect, the number of detectors in a given area. Detectors spaced too closely may give rise to crosstalk. 2. In the cross section of a fiber optic bundle, the ratio of fiber...

The ratio of the active core area of a fiber bundle to the total area at its light-emitting or receiving end.

The production of a positron-electron pair by a photon having energy greater than one mega-electron-volt, whereby some of the photon energy is converted to the rest mass of the pair.

In interlaced television scanning, an effect in which the lines of one field fail to fall exactly within the lines of the following field, both fields comprising one frame of the picture. The lines...

Black and white film that has a wavelength sensitivity similar to that of the eye.

Color sensitivity extended to cover the entire visible spectrum out to the red.

A camera designed to form a continuous record of an expansive section of the horizon. The typical panoramic camera is mounted to rotate about a vertical axis. A slit opening in the film plane and the...

The image distortion produced by a panoramic camera with a swinging lens or a swinging mirror in front of a fixed lens. The magnification is greatest in the center and diminishes to each side in the...

A lens system that is capable of producing a 360° image, or one that is very close to that. In recording, the image may be formed on a curved strip of film surrounding the lens, resulting in a...

A telescope so manufactured that the image remains erect and the position of the eyepiece is unchanged as the line of sight is pointed in any horizontal direction.

The condition in which the index of refraction in an optical fiber varies as a parabolic function of the radius.

A condenser composed of a paraboloidal reflector and used for dark-field illumination.

A concave mirror that has the form of a paraboloid of revolution. The paraboloidal mirror may have only a portion of a paraboloidal surface through which the axis does not pass, and is known as an...