Photonics Dictionary

A laser that generates a succession of pulses at a high enough repetition rate to appear continuous. The pump source is switched on for short intervals, nominally equal to the lifetime of the...

In the dye laser, the molecule that takes out energy from the triplet state during collisions between the dye and quencher to achieve long-pulse emission.

The inhibition or elimination of one process by another process. The stimulated emission of a laser oscillator can be quenched by a pulse of radiation of the same frequency traversing the oscillator...

The radiation emitted in semiconductors when electrons in the conduction band recombine with holes in the valence band. If population inversion occurs between portions of the valence and conduction...

A pulsed laser that emits a recurring pulsed output. Frequency of the pulses emitted is known as pulsed recurrence frequency (PRF). When the PRF or duty cycle is very high, repetitively pulsed lasers...

Rhodamine refers to a family of fluorescent organic dyes that are widely used in various fields, including biology, chemistry, medicine, and materials science. These dyes are known for their bright...

Sapphire optical fiber is a type of optical fiber made from single-crystal sapphire, which is a form of aluminum oxide (Al2O3) that is highly transparent in the infrared region of the electromagnetic...

A saturable absorber is a type of optical device that exhibits variable absorption properties depending on the intensity of incident light. In essence, it becomes less absorbent as the light...

A nonlinear label-free imaging technique commonly used during surgical procedures for the visualization of collagen fibers and muscle tissue (myosin) with submillimeter resolution. During the...

A self-interference effect that generates random patterns; secondary speckle pattern (SSP) typically occurs in diffuse reflections of a laser on paper, white paint or rough surfaces. By tracking both...

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...

Single-molecule Förster resonance energy transfer (smFRET) is a specialized technique in biophysics and molecular biology used to study the distances and dynamic interactions between two...

A single-photon avalanche diode (SPAD) is a specialized type of photodetector designed to detect extremely weak optical signals, down to the level of single photons. SPADs are widely used in...

A solid-state laser is a type of laser that uses a solid gain medium (as opposed to a liquid or gas) to produce coherent light. The term "solid-state" refers to the fact that the active medium, where...

Any isolated wave that propagates without dispersion of energy. Specifically to photonics, an ultrashort pulse of laser light that propagates through a waveguide without characteristic chromatic...

A color center laser whose output is coupled to an external control laser cavity and then fed back to the main laser cavity to provide enhanced pulse shaping, leading to ultrashort pulse generation.

A spatial light modulator (SLM) is an optical device that modulates or manipulates the amplitude, phase, or polarization of light in two dimensions, typically in the form of an array. SLMs are...

Spectral flow cytometry is an advanced flow cytometry technique that expands the capabilities of traditional flow cytometry by utilizing spectral information from fluorochromes to enhance...

A spheric lens, also known as a spherical lens, is a type of optical lens with at least one surface that is part of a sphere. This means that the lens surface is curved in a symmetrical manner,...

A semiconductor laser that operates in the infrared and that is pumped with strong pulses of radiation from a second laser. Dependent on quantum-mechanical principles, it can be tuned over a large...

A memory system composed of a stack of holographic plates, a mode-locked laser and a rapid detector array. Ultrashort laser pulses are used to extract information from the stack. In this way, storage...

Light from a pulsed laser focused into nonsaturable absorbing fluid that generates a strongly backscattered light beam with a frequency higher than that of the incident light.

A streak camera is a specialized instrument used to capture and analyze ultrafast phenomena, such as extremely short pulses of light or rapidly changing events. Unlike traditional cameras that...

A pulsed interferometer that permits the continuous quantitative mapping of the surface deformation of an adaptive optical element (e.g., a deformable mirror) and provides the capability for...

Supercontinuum refers to a broad spectrum of light that spans a wide range of wavelengths, typically from the visible to the near-infrared or even mid-infrared regions of the electromagnetic...

Observed phenomenon in laser pulses in which a large number of excited electrons are created and in which multiphoton processes have produced seed electrons, and excited neutral atoms are...

The technique of generating ultrashort -- down to subpicosecond -- pulses by pumping a dye laser with mode-locked laser pumps with cavity lengths the same as, or a submultiple of, that of the dye...

A terahertz spectrometer is a scientific instrument used to measure and analyze the properties of materials in the terahertz frequency range, typically spanning from about 0.1 to 10 terahertz (THz),...

Time-correlated single photon counting (TCSPC) is a technique used in photon counting applications, particularly in the field of experimental physics, biophysics, and fluorescence lifetime imaging...

A Ti:sapphire laser is a type of solid-state laser that utilizes a titanium-doped sapphire crystal as the gain medium. The name Ti:sapphire comes from the combination of titanium (Ti) as the dopant...

Abbreviated TEA CO2 laser. A gas laser that provides shorter pulses and higher peak powers than conventional CO2 lasers. The electrical excitation pulse occurs transversely to the optical axis...

Also known as TEA laser. A coherent optical source with a wide wavelength range in the infrared, visible and ultraviolet that uses an electrical discharge transverse to (across) the optical axis to...

An ultrafast pulsed laser is a type of laser that emits extremely short pulses of light with durations typically on the order of femtoseconds (10-15 seconds) or picoseconds (10-12 seconds). These...

A laser capable of generating light pulses that last only a few femtoseconds. This can be achieved by nonlinear filtering to increase bandwidth and compress the pulse or by passive mode-locking or...

A pulsed laser having molecular nitrogen as laser material and a wavelength output of 337 nm in the ultraviolet region. It is essentially a channel flashtube in which a pulse is applied to the...

Volume Bragg gratings (VBGs) are specialized optical elements that consist of periodic variations in refractive index throughout the volume of a transparent material, typically a photosensitive glass...

Volumetric imaging refers to the capture, visualization, and analysis of three-dimensional (3D) information from a volume of space. Unlike traditional two-dimensional (2D) imaging, which provides...

An extremely wide emission spectrum generated by the nonlinear effects created when a high peak power from a short-pulse laser is focused into a water or carbon tetrachloride cell. The resulting...