The use of photographic emulsions to detect and determine the amounts of ionizing radiation, such as x-rays and gamma rays, in an area. This is accomplished by exposing the emulsion to the radiation for a set interval and analyzing the resulting...

A technique used in photogrammetry to ensure parallelism during projection printing. Failure to do this will change a...

Film that produces color negatives or transparencies by the use of three emulsions, one coated over the other, that are each...

A cylindrical lens is an optical component that has different curvatures along its two orthogonal axes, resulting in a shape...

A method of measuring negatively charged phase ions using a color-center or lead-salt diode laser.

The principle stating that two diffraction screens, one being exactly the negative of the other, will form the same...

An electrode used to release photoelectric emission when irradiated, making it then the irradiated negative electrode of a...

A small defocused Galilean telescope mounted in a hole in a door. Viewed from inside through the positive lens, a wide-angle...

Germanium crystal refers to a crystalline form of the element germanium (Ge), which is a metalloid and semiconductor...

Gram-negative bacteria are a group of bacteria that possess a cell envelope composed of a thin layer of peptidoglycan...

Type of solid-state display tube in which the readout surface is coated with a material that changes color when positively...

A double-surfaced catadioptric spherical mirror whose spherical first surface consists of a negative meniscus (concave) lens...

Photoresist is a light-sensitive material used in photolithography processes, particularly in the fabrication of...

A PIN photodiode is a type of photodetector or semiconductor device used to convert light signals into electrical signals....

Also known as reversed telephoto lens. A lens consisting of an ordinary objective with a negative component near its front...

The points on a photographic negative that are of equal density.

The rule stating that positive uniaxial crystals have greater absorption with respect to the extraordinary component of...

A method of reducing dark current in charge-coupled devices by holding all the clocks at negative voltage during the...

An atom that has gained or lost one or more electrons and, as a result, carries a negative or positive charge.

A telemicroscope in which a negative eyepiece is used to produce erect images.

1. The use of an electronic microdensitometer to measure points of equal density on a photographic deposit. 2. A technique...

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

Hydrophilic is a term used to describe substances or materials that have an affinity for water. The word hydrophilic comes...

In astronomy, the relative brightness of a celestial body. Originally a scale from 1 to 6, where 1 represented the brightest...

An artificial material, engineered to have a negative refractive index value, such that light or any other form of...

The focal length of a lens is the distance between the lens's optical center (or principal point) and the image sensor or...

Refers to transistors in which the working current flows through two types of semiconductor material: N- and P-type. In...

Van der Waals forces refer to the attractive or repulsive forces between molecules (or parts of molecules) that arise from...

Brillouin scattering is a phenomenon in physics where an incident electromagnetic wave (usually light) interacts with...

An electrophoretic display, often referred to as an electronic paper display or e-paper display, is a type of electronic...

A photocathode having a P-type semiconductor with a work function less than its bandgap. The photocathode can release a...

Sets of lenses (positive, negative and cylindrical) usually mounted in circular rims suitable for slipping into trial...

The radiography of small objects having detail too fine to be seen by the unaided eye. The resulting negative, when...

A chemical used in the developing of positive photographs that incites oxidation and thereby dissolves the negative silver...

A short term for latent image intensification, a process much like hypersensitizing in photography, but used after exposure...

Amplification; the result of the excess of stimulated radiation over absorbed radiation.

A device that uses four electrodes set in an alternating positive-negative polarity series to focus the beams of charged...

State typically studied in liquid crystals in which the dielectric coefficient parallel to the director is less than the...

A nonluminous area around a negatively charged probe that is inserted into the positive column of an arc or glow discharge.

A refracting telescope that yields an erect image by the use of a positive lens for its objective and a negative lens for...

A method used in imaging to detect subtle differences between two apparently similar pictures. It can be achieved by...

The condition in which there are more atomic systems in the upper of two energy levels than in the lower, so stimulated...

Plasmonics is a field of science and technology that focuses on the interaction between electromagnetic radiation and free...

Gram-positive bacteria are a group of bacteria that have a thick cell wall composed primarily of a substance called...

Measurement derived from calculation when incident flux of a negative is entirely diffuse and all radiation transmissions...

Refers to the transistors in which the working current flows through only one type of semiconductor material, either P-type...

An isotope of cesium that emits negative beta particles and has a half-life of 2.19 years; its applications include...

A negatively charged elementary particle. See electron.

The structure that holds the photographic negative in a proper position that is both flat and parallel to the lens plane, as...

Equipment that supports microscopic live-cell imaging by managing the gas, media perfusion, temperature and other factors to...

A process used in pyrometry and photothermometry to create a photographic record of a surface's temperature gradients....

An emulsion in which grains of the photosensitive material silver halide are deposited. Each grain, when exposed to light,...

1. The negative electrode of a device in an electrical circuit. 2. The positive electrode of a primary cell or storage...

A photographic enlarger with a fixed negative plane and a fixed paper plane, often using a roll of paper that is advanced...

The underexposed collodion that is present on a glass negative as a positive when backed with material.

A panel of photoconductive and electroluminescent layers used as either a positive or negative image intensifier, depending...

A term used to denote a concave surface having too long a radius of curvature. That is, its negative power is too small or...

The improper exposure of a radiation-sensitive medium that results when there is too much radiation exposing the medium, or...

The coefficient termed by Callier as the ratio between the density of photographic negatives measured by parallel light and...

An instrument consisting essentially of a tube 160 mm long, with an objective lens at the distant end and an eyepiece at the...

A compound lens consisting of two negative lenses of flint glass. A double-convex lens of crown glass is cemented between...

A lens aberration, resulting from different magnifications in the various lens zones, that occurs in that part of the image...

A vision defect commonly referred to as nearsightedness. The defective condition results when the image of a distant object...

The transmittance of a point on a photographic negative equal to the log to the base 10 of the reciprocal of the...

A lens whose focal length is roughly equal to the diagonal of the negative format of the camera on which it is mounted.

When a stereo pair of images is switched so that the right eye sees the left image and the left eye the right, the stereo...

A family of semiconductor switching devices of which the silicon-controlled rectifier and the triac are most commonly used....

The nonluminous area that divides the negative glow from the positive column in a Crookes tube under conditions of moderate...

The property exhibited by a substance having electrical conductivity that decreases as the intensity of the incident visible...

A negative powered lens with one surface convex and the other concave, the latter having the greater curvature. It also is...

An instrument that uses a beam of light to scan a color transparency, and three differently filtered photosensors to record...

In chemistry, a halide refers to a chemical compound containing one or more halogen atoms bonded to another element. The...

Characterizes a substance whose plane of polarization is rotated counterclockwise as the observer looks through the material...

Metamaterials are artificial materials engineered to have properties not found in naturally occurring substances. These...

The simplest lens in which all primary aberrations may be corrected. It consists of two positive crown elements on either...

A three-terminal semiconductor having only one PN junction and a stable, open-circuit, negative-resistance property.

Photolithography is a key process in the manufacturing of semiconductor devices, integrated circuits, and...

Carrier injection refers to the process of introducing charge carriers (either electrons or holes) into a semiconductor...

A charged elementary particle of an atom; the term is most commonly used in reference to the negatively charged particle...

A direct recording photometer that is designed to scan a photographic negative to determine its points of isodensity.

A ghost image that has the reverse lightness relations of the original image. This phenomenon is a common optical illusion...

An eyepiece located at the near end of the microscope tube. It often is a simple Huygens eyepiece, but compensating and...

A doubly refracting mineral used to produce polarizing prisms. It is uniaxial negative and in the trigonal division of the...

A transparent block shaped accurately to reverse curvatures of the components it is used to test. By contacting an...

A light source made up of silicon carbide or carborundum. It is resistant to the negative temperature coefficient and...

A negative lens used to increase the effective focal length of a telescope objective.

Three filters used in making a color print of a color negative, red, green and blue-violet, respectively. Each filter...

The film used in photographic dosimetry to record the types and amounts of ionizing radiation, such as x-rays and gamma...

Nanophotonics is a branch of science and technology that explores the behavior of light on the nanometer scale, typically at...

The process of microphotography that involves the reduction of the original at a ratio greater than 100 to 1. The process is...

In a cold-cathode tube, the luminance between the cathode dark space and the Faraday dark space. In a vacuum tube, the...

A concave surface that has too much negative power; i.e., its radius of curvature is too short. This condition can be...

Lithography is a key process used in microfabrication and semiconductor manufacturing to create intricate patterns on the...

The negative distortion that causes a square grid pattern to be imaged as barrel-shaped.

A convention that defines specific dimensions of an optical system, such as the image distance or radius of curvature of a...

A lamp in which the ionization of the inert gas contained in it produces a glow in the space close to the negative electrode.

An intensified charge-coupled device that uses a large negative charge at the grid to switch off the flow of electrons at...

A uniaxial, birefringent crystal such as calcite or ruby in which the velocity of the extraordinary ray surpasses that of...

An exciton is a quasiparticle that represents the bound state of an electron and a hole in a solid-state material, typically...

A number that indicates the magnitude of the shift in a solid of positive and negative charges in opposite directions when a...

The area of low-level luminance lying between the cathode and the negative glow in a glow-discharge, cold-cathode tube.

Complementary metal-oxide-semiconductor (CMOS) refers to a technology used in the fabrication of integrated circuits,...