Photonics Dictionary

An active matrix liquid crystal display (AMLCD) is a type of flat-panel display technology that utilizes an array of thin-film transistors (TFTs) to control the individual pixels on the screen. This...

The term acute bisectrix is used in mineralogy and crystallography to describe a specific optical property of minerals, particularly in relation to their crystal structure and light behavior. ...

The angle between the most divergent rays that can pass through the lens to form an image. In a birefringent crystal light modulator or Pockels cell, the maximum angle in the incident light rays that...

Birefringence is an optical property of certain materials that causes them to exhibit different refractive indices for light of different polarizations. In other words, when light passes through a...

A technique in which a beam of x-rays is directed against a crystal, the atoms of which, because of their lattice arrangement, reflect the ray in the same way as a series of plane surfaces. If the...

The scattering of x-rays by the regularly spaced atoms in a crystal. The angle at which the reflection occurs is known as the Bragg angle.

The law expressing the condition under which a crystal will reflect a beam of x-rays with the greatest amount of distinction or resolution and, at the same time, denoting the angle at which the...

The dispersion of a light ray striking the surface of a biaxial crystal, in which the resulting rays are reflected in a conical manner.

The naturally occurring crystalline form of silicon dioxide. It is slightly birefringent and exhibits rotary dispersion of light rays transmitted along the crystal axis, both right-hand and left-hand...

The photographic record of the diffraction pattern formed when x-rays pass through a crystal.

The analysis of the atomic structures within crystals by means of x-ray diffraction.

A cylindrical lens is an optical component that has different curvatures along its two orthogonal axes, resulting in a shape resembling a cylinder. Unlike spherical lenses, which have the same...

Diffraction is a fundamental wave phenomenon that occurs when a wave encounters an obstacle or aperture, causing the wave to bend around the edges and spread out. This effect is most commonly...

The separation of unpolarized light into two plane-polarized elements by a doubly refracting crystal. When a crystal, such as calcite, is placed between the eye and a pinhole in a card, two bright...

A ray that has a nonisotropic speed in a doubly refracting crystal. It does not necessarily obey Snell's law upon refraction at the crystal surface.

A crystal that is devoid of any mosaic structure and that can reflect x-rays, relative to the Darwin-Ewald-Prins law.

Also known as the Bragg spectrometer. A system used for the x-ray analysis of crystal structure. In the instrument, a homogeneous beam of x-rays is directed on the known face of a crystal and the...

A laser crystal, also known as an active medium or gain medium, is a solid-state material used in the construction of lasers. The primary function of the laser crystal is to amplify light by...

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

Liquid crystal on silicon (LCoS) is a display technology that combines liquid crystal materials with silicon-based semiconductor technology to create high-resolution, high-quality images. LCoS...

An instrument that produces an intense, tightly focused beam of ions to stimulate emissions from a minute section of a sample undergoing spectroscopic analysis. The ion beams found in microprobes are...

A uniaxial, birefringent crystal such as calcite or ruby in which the velocity of the extraordinary ray surpasses that of the ordinary ray. This can also be defined as the index of refraction of the...

A prism invented by William Nicol in 1828 that is made of calcite, the end faces of which are ground to an angle of 68° between one vertical side and the end surface. The prism is cut diagonally...

A transparent crystalline substance that displays the same optical properties (i.e. refractive index) in all directions such that all light rays behave the same in all directions of propagation and...

A transparent crystalline substance in which the refractive index of the optic axis (extraordinary axis) is different from the other two crystal axes. Two polarization directions are allowed for any...

A technique proposed for studying the atomic structure of crystals by measuring the interference pattern generated when the crystal is illuminated by a burst of finely tuned x-rays. The resulting...

The property exhibited by certain birefringent crystals in which the degree with which they transmit polarized light is different, depending on whether the ray is ordinary or extraordinary. An...

A uniaxial, birefringent crystal having an ordinary ray with a higher velocity than the extraordinary ray.

A technique used in radiography to determine a crystal's structure by obtaining radiographs of it in powder form, normally by the use of a powder camera that forms an image of the crystal's x-ray...

A plane passing through a crystal that has the optic axis of the crystal and the light ray under consideration.

Protein crystallography is a scientific technique used to determine the three-dimensional structure of proteins at atomic resolution. It involves growing crystals of a protein of interest and then...

Quantum dot thin films refer to thin layers or coatings composed of quantum dots deposited onto a substrate surface. Quantum dots are nanoscale semiconductor particles typically ranging from a few to...

The analysis, by x-rays, of the crystalline structure and other properties of metals and alloys.

Raman scattering, also known as the Raman effect or Raman spectroscopy, is a phenomenon in which light undergoes inelastic scattering when interacting with matter, such as molecules, crystals, or...

A scintillation crystal, also known simply as a scintillator, is a material that emits light when it interacts with ionizing radiation such as gamma rays, x-rays, or charged particles. The emitted...

A scintillation detector is a radiation detection device that utilizes scintillation crystals to detect and measure ionizing radiation, such as gamma rays, x-rays, or charged particles. It consists...

A form of liquid crystal in which flow does not take place in the usual manner. When examined with polarized light, the substance often forms drops that display a series of fine lines. X-ray...

A ruggedized scintillation counter used in oil well logging. The cylindrical housing contains a gamma ray source, a crystalline scintillator and a photomultiplier tube. As the sonde is drawn through...

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...

A synchrotron is a type of particle accelerator that uses magnetic fields to steer charged particles, typically electrons or positrons, in a closed, circular or elliptical path. The name synchrotron...

The Weissenberg method, named after the German physicist Karl Weissenberg, is a technique used in x-ray crystallography for obtaining high-quality diffraction patterns from single crystals. This...