Photonics Dictionary

A technique whereby two laser beams, one at an excitation wavelength and the second at a wavelength that produces Stokes Raman scattering, interact coherently in a sample, producing a strong...

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 coherent fiber bundle (CFB), also known as a coherent fiber optic bundle, is an assembly of multiple optical fibers arranged in a specific geometric pattern to maintain the spatial coherence of...

A light source that is capable of producing radiation with waves vibrating in phase. The laser is an example of a coherent light source.

The manifestation of light from scatterers outside the plane of the object in coherent light systems. The output of these systems is often marred by this noise.

The use of phase conjugation or other methods to increase the power density of a laser beam under adverse atmospheric conditions.

Radiation in which the phase relationship between any two points in the radiation field has a constant difference, or is exactly the same in either the spatial or the temporal mode throughout the...

In optics, the term denoting the lack of a fixed phase relationship between two waves. If two incoherent waves are superimposed, interference effects cannot last longer than the individual coherent...

A bundle of filaments of optical glass or other transparent materials that transmit only light, not optical images. The arrangement of the individual fibers in the bundle is not sufficiently regular...

The production of holograms initially from either conventional photographs or incoherent optical equipment.

A function that quantifies the performance degradation of coherent communications systems, imaging systems and all systems that rely on the spot size of a laser beam that has propagated along an...

An assembly of optical fibers that will not transmit coherent images or information because the relationship of the fibers on either end of the assembly is random; Noncoherent fiber bundles are...

Radiation having waves that are out of phase in space and/or time.

Measures by heterodyning interferometry the local slope of a vibrating sample. The method allows the reconstruction of a three dimensional map of the surface in order to determine the slope and...

The correlation of radiation between the phases of monochromatic radiation emanating from two separate points.

The optical reconstruction of image information contained in a sound field. First the diffraction pattern, formed by an object irradiated by ultrasonic rays, interferes with a mutually coherent...

An assembly of fibers in which the coordinates of each fiber are the same at the two ends of the bundle. Also called coherent bundle.

Attosecond-pump attosecond-probe spectroscopy (APAP) is an advanced technique in ultrafast spectroscopy that allows scientists to study the dynamics of electronic processes occurring on extremely...

Two formulas used in diffractometer analysis, the first giving the individual diffraction patterns of each aperture, the second representing the constant of the degree of an incoherent circular...

Degradation factor in coherent light systems where the amplitude of the recorded signal is decreased as the number of object points is increased, resulting in poor noise performance.

The action of a biological system responding to a single or multiple coherent particles of light produced from a laser source. Examples of laser biostimulation include: retinal interaction of light...

A blue diode laser is a type of semiconductor laser that emits light in the blue wavelength range of the electromagnetic spectrum, typically between 400 and 500 nanometers. Diode lasers are compact,...

A Bose-Einstein condensate (BEC) is a state of matter that forms at temperatures close to absolute zero. It is named after Satyendra Nath Bose and Albert Einstein, who independently predicted the...

A ring dye laser that uses prisms and a saturable absorber within the laser cavity to shape and shorten the pulses generated. Counterpropagating modes oscillating simultaneously in the ring...

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...

A confocal resonator, also known as a confocal cavity or confocal laser resonator, is a type of optical resonator configuration used in laser systems. The term confocal in this context refers to the...

The coupled pairs of electrons that carry supercurrents through the body of a superconductor, relative to a coherent macroscopic wave function with the superconductor.

A quantitative measurement of the coherence of a light source; equal to the visibility (V) of the fringes of a two-beam interference test: where Imax equals the intensity at a maximum of the...

Optical elements that use diffraction to control wavefronts. Diffractive optical elements include diffraction gratings, surface-relief diffractive lenses, holographic optical elements and...

A diode laser is a type of laser that uses a semiconductor diode as the active medium to generate coherent light. Semiconductor diodes are electronic devices that conduct electricity primarily in one...

A diode-pumped solid-state laser (DPSSL) is a type of laser system that uses semiconductor diode lasers to pump energy into a solid gain medium, resulting in the generation of coherent light. This...

A distributed feedback laser (DFB laser) is a type of semiconductor laser diode designed to emit coherent, narrow-bandwidth light with precise control over the wavelength. It achieves this through a...

An edge-emitting light-emitting diode is a type of LED structure where light emission occurs primarily along the edge of the semiconductor chip rather than from the surface. Edge-emitting LEDs are...

A maser that relies on the fact that electrons in orbital motion in high-magnetic fields will emit energy at the cyclotron frequency. The transfer of energy is from the bunching of the electrons by...

A femtosecond laser is a type of laser that emits ultrashort pulses of light with durations on the order of femtoseconds, where one femtosecond is equal to 10-15 seconds. These lasers are capable of...

A rigid or flexible, concentrated assembly of glass or plastic fibers used to transmit optical images or light. See aligned bundle; incoherent bundle.

A fiber laser is a type of laser in which the active gain medium is an optical fiber doped with rare-earth ions such as erbium, ytterbium, or neodymium. Fiber lasers generate coherent light through...

A plate made up of thousands of glass fibers arranged parallel to one another, i.e., in a coherent bundle, and fused together so that it is hermetically tight. It transfers an image from one plane to...