Photonics Dictionary: L

The photographic record of the diffracted beams formed when heterogeneous x-rays emerging from a pinhole or slit impinge upon one crystal.

The angle between the light input propagation vector and the optical axis of an optical fiber or fiber bundle.

The numerical aperture of an optical system used to couple (launch) power into an optical waveguide.

A fiber used in conjunction with a source to excite the modes of another fiber in a particular fashion.

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...

Label-free refers to a technique or method that does not require the use of additional labels, tags, or markers to detect or identify specific components or entities. In various scientific and...

A dark band that may appear in the field of crossed Nicol prisms with a powerful source such as the sun because the light is not strictly parallel and is not extinguished immediately.

A metal tool used to grind lenses with loose abrasive (see diamond cutting tool). The functional surface of the lap is carefully formed to be opposite the curve to be produced on the glass (concave...

Laser ablation is a process that involves the removal or erosion of material from a target surface using laser energy. This technique is widely used in various scientific, industrial, and medical...

A process and method by which manipulation and orientation of a given number of directed laser beams decreases the motion of a group of atoms or molecules such that their internal thermodynamic...

Laser drift typically refers to a phenomenon where the frequency or wavelength of a laser source gradually changes over time. In the context of lasers, stability in terms of frequency or wavelength...

Laser lithotripsy is a medical procedure that uses laser energy to break down or fragment stones in various parts of the body, particularly in the urinary and biliary systems. The term "lithotripsy"...

Laser marking is a process in which a laser beam is used to mark or engrave a surface by altering its properties or appearance. This technique is widely used for labeling, identification, and...

The laser output refers to the generated and emitted light produced by a laser system. This output is characterized by several key properties that distinguish lasers from other light sources. These...

Laser peening is a surface enhancement technique used to improve the mechanical properties of materials, particularly metals. It involves the use of high-energy laser pulses to generate shockwaves on...

Optical source intended to reduce bleeding as well as to abet wound or vessel healing through cauterization, used in eye treatment procedures such as for macular degeneration.

Laser powder bed fusion (LPBF) is a type of additive manufacturing (AM) or 3D printing technology that uses a high-power laser to selectively fuse or melt layers of powdered material to build up a...

A fast-action shutter inserted between one end of a laser rod and the end mirror; when inserted to prevent emission and then quickly removed, it causes the laser to discharge suddenly with great...

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...

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...

A technique for confining atoms, molecules or small particles within one or more laser beams. This can be accomplished through the use of a single focused beam or multiple intersecting beams. With a...

A system that uses the heat from a pulsed laser to weld metals. Because of the rapidity and localization in which the welding takes place, metals of vastly dissimilar melting points can be welded...

An extensometer used to measure deformations in the thickness of a plate caused by tension, compression or other stress.

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

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 dial depth gauge graduated in diopters; a lens measure.

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,...

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...

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...

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 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...

Phenomenon caused by an ultrashort and ultra-intense light pulse propagating in a Kerr medium, such as air or water. When the pulse's power exceeds the critical power (approximately 3 GW in air),...

Technique for measuring the volume bulk of materials as they move along a conveyor with an accuracy of better than 1 percent. Based on the use of high-resolution arrays of solid-state detectors, the...

An LED, or light emitting diode, is a semiconductor device that emits light when an electric current passes through it. LEDs are widely used in various applications due to their energy efficiency,...

Line scan refers to a method of capturing images or data by scanning a single line at a time, as opposed to capturing the entire image simultaneously. This technique is commonly used in various...

A spectrum formed by radiation whose energy values of the property being measured cluster about at least one discrete value, as opposed to a continuous spectrum. The actual width of the spectral line...

An alphanumeric display formed by a layer of liquid crystal material sandwiched between two sheets of glass; a transparent conductive coating on the glass is etched to form the character segments. An...

A form of mirage where objects near or just below the horizon appear in enlarged or distorted form because of atmospheric refraction. The glow in the sky caused by the presence of light below the...

Low Earth orbit (LEO) refers to a region in space that is relatively close to Earth's surface, typically characterized by altitudes ranging from approximately 180 to 2,000 kilometers (112 to 1,242...

The analysis of structural and molecular dynamics caused by low temperature.