Photonics Dictionary: L

Laser sintering is an additive manufacturing (AM) or 3D printing technology that involves using a laser to selectively fuse powdered materials, typically polymers or metals, layer by layer, to create...

An instrument usually consisting of a very long interferometer, 3 to 800 m, and a laser light source for the study and measurement of strain, such as those formed by earth tides and gravitational...

Laser surgery refers to a medical procedure in which a laser, or focused beam of light, is used as a precision tool to cut, vaporize, coagulate, or otherwise modify tissues for therapeutic or...

Laser texturing is a manufacturing process that involves using a laser beam to selectively modify the surface of a material, creating textures, patterns, or microstructures. This technique is...

The device, usually made of glass or a similar material, that contains the resonant cavity and optics of a gas laser.

A system that uses a continuous-wave laser to measure the velocity of an object by focusing the laser beam on the object, perpendicular to its direction of motion. An optical grating receives...

Laser viewing cards, also known as laser alignment cards or laser safety cards, are specialized cards or sheets designed to visualize laser beams or assist in aligning optical equipment while...

A laser, which stands for "light amplification by stimulated emission of radiation," is a device that produces coherent and focused beams of light through the process of optical amplification based...

A type of fluorescence spectroscopy in which an excimer laser, a dye laser and a frequency-doubling device are used to detect polycyclic hydrocarbon atoms to a part-per-billion level.

Laser-induced fluorescence (LIF) is a spectroscopic technique that involves using a laser to excite molecules or atoms, leading to their emission of fluorescence light. This technique is widely used...

Laser-mediated gene transfer refers to a technique in molecular biology and genetic engineering that utilizes lasers to introduce genetic material into cells. This method is a type of gene delivery...

A machining process that uses a laser to cut three-dimensional molds or models.

The pattern of physical or chemical changes that has taken place in a photographic emulsion, by its exposure to light, that will form a visible image when the emulsion is developed. Also known as...

A power loss caused by transverse or lateral deviation from optimum alignment of source to optical waveguide, waveguide to waveguide, or waveguide to detector.

A lateral shearing interferometer is an optical device used in interferometry to measure phase differences between two beams of light. Interferometry is a technique that combines and analyzes...

A Laurent polarimeter is an instrument used in optics for measuring the rotation of plane-polarized light caused by optically active substances. Optical rotation, also known as optical activity, is a...

In physics, the law of reversibility is often associated with the concept of reversibility in thermodynamics. The law asserts that any process that occurs in a closed system can, in theory, be...

The process of removing some of the constituents of a glass surface by chemical action.

A photoconductive cell having greatest sensitivity in the infrared region. The photosensitive material of the cell is lead sulfide, which is deposited on a glass plate.

In an optical waveguide, a ray for which geometric optics would predict total internal reflection at the core boundary, but which suffers loss by virtue of the curved core boundary.

An erecting prism that inverts and reverses the image. It displaces the optical axis but does not deviate it.

The mechanical structure that holds a number of individual lens elements.

The metal tube that maintains the optical components of a lens in proper relationship. Some lenses are mounted in metal cells, which in turn are screwed to the front and rear of a shutter or lens...

Lens testing equipment refers to a range of specialized tools and instruments used to evaluate the optical performance, quality, and characteristics of lenses. These instruments are essential for...

A lens is a transparent optical device that focuses or diverges light, allowing it to pass through and form an image. Lenses are commonly used in optical systems, such as cameras, telescopes,...

A hologram formed without lenses and with the object and reference points sharing the same plane. In the initial recording, each object point produces fringes having one spatial frequency across the...

Lensless microscopy, also known as computational or holographic microscopy, is an imaging technique that captures and reconstructs microscopic images without the use of traditional lenses. Instead of...

A type of additive color photography using a lenticular structure impressed on a film base and a camera lens with a filter having three sectors of red, blue and green. Exposure of the film through...

A type of stereoscopic photography in which a pair of lenses focuses a pair of images, relative to the positions of the two eyes, onto film through a lenticular screen, which records the images as an...

The generic term describing the class of light particles having no strong interactions.

Lidar, short for light detection and ranging, is a remote sensing technology that uses laser light to measure distances and generate precise, three-dimensional information about the shape and...

The visual perception of contrasting forms is more difficult if the forms have the same luminance but different chromaticities, than if the forms have the same chromaticity but different luminances.

Electromagnetic radiation detectable by the eye, ranging in wavelength from about 400 to 750 nm. In photonic applications light can be considered to cover the nonvisible portion of the spectrum which...

A device that serves to emit light of the same wavelength as the input light, only with an increase in intensity. It may be a solid-state device comprising photoconductive and luminescent layers...

Light diffusion refers to the process by which light is scattered or spread out in various directions as it interacts with a medium or material. Unlike direct transmission through a transparent...

The process whereby white light is separated into its component wavelengths. Light beams of different wavelengths are separated from each other by undergoing a different angular deviation. Prisms and...

LiFi, short for light fidelity, is a wireless communication technology that utilizes visible light or infrared light to transmit data. Developed as an alternative or complementary technology to...

The term light field refers to the spatial distribution of light rays traveling in all directions through a given space. It includes information about the intensity and direction of light rays at...

Any device that is used to sense and measure light. See exposure meter; photoelectric exposure meter; photoelectric photometer; reflected light meter.

A device that is designed to modulate a beam of light, usually from a laser source, by acting upon the beam directly. The three general types of devices operate in an acousto-optic, electro-optic or...

That property of a substance that determines that there will be a decrease in conductivity when exposed to light radiation.