Photonics Dictionary

Power modulation refers to the intentional variation of power levels in a signal, often in the context of electronic communication systems. This modulation technique is used to encode information...

The minimum amount of strength characteristic of an optical fiber, as determined by proof stressing; expressed in thousands of pounds of pressure per square inch.

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...

Radiant power emitted into a full sphere (4p steradians) by a unit area of a source; expressed in watts per square meter.

The mean square difference in refractive index for two separate points in space.

A ring laser gyroscope (RLG) is a type of gyroscope that uses laser light to detect and measure changes in orientation. It operates based on the Sagnac effect, which is a fundamental principle of...

Self-phase modulation (SPM) is a nonlinear optical phenomenon that occurs when an intense laser beam passes through a medium, causing a change in the phase of the light due to its interaction with...

In sensitometric testing, a series of areas progressing by equal density steps (usually the increments between steps are equal to the logarithm of the square root of two). They are commonly used in...

The unit solid angle subtended at the center of a sphere by an area on its surface equivalent to the square of the radius; the unit of solid angular measurement, often used in problems of...

The mean square difference in a spatial parameter at points spaced a given distance.

A technique used to suppress extreme noise amplification during digital image reconstruction that relies on smoothing and differentiation of the data by simplified least squared procedures.

The magnetic flux density given by a magnetic flux of one weber per square meter. (T).

A test similar to the Knoop hardness test, but used for fractured material. The indenter is a square-based pyramid-shaped diamond.

An optical element having plane-inclined surfaces. Usually the faces are inclined toward one another at very small angles. Wedges divert light toward their thicker portions, and may be circular,...

A well plate, also known as a microplate or microtiter plate, is a flat plate with multiple small wells or depressions arranged in a grid pattern. Each well serves as a separate container for holding...

A method that embraces the classical approach to image restoration and attempts to minimize the mean square difference between the original ungraded signal and the restoration.

A plate of glass, usually a photograph, on which there is a central spot surrounded by concentric annular zones, alternately opaque and transparent, the radii of the boundaries between the zones...