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Bristol Instruments, Inc. - 872 Series High-Res 4/24 MR

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290 terms

Photonics Dictionary

molecular beam epitaxy — A well-controlled thin film technique for growing films with good crystal structure in ultra high vacuum environments at very low deposition rates. MBE is also commonly used in the manufacture of semiconductor devices and solar cells.

Beer-Lambert law

Combination of Beer's and Lambert's (absorption) laws.

bubble chamber

A large tank filled with liquid hydrogen, with a flat window at one end and complex optical devices for observing and photographing the rows of fine bubbles formed when a high-energy particle...

bubble chamber optics

Specially designed optics for the observation and photographing of hydrogen in a bubble chamber.

bubble chamber photography

The photographic recording of gas bubbles produced when particles traverse liquid hydrogen in a bubble chamber.

counting chamber

In microscopy, the chamber that is contained on a microscope slide to hold a certain amount of fluid. It is calibrated accurately to determine the number of cells and other elements while the...

dember effect -> photodiffusion effect

The potential difference between two areas of a semiconductor when one is exposed to light.

effective f number

For a lens with an obscured or noncircular aperture, the focal length divided by the effective aperture.

embedded laser

The term "embedded laser" typically refers to a laser device that is integrated or embedded into a larger system or structure. In this context, "embedded" implies that the laser is an integral part...

embedded vision

Embedded vision refers to the integration of computer vision technologies into various embedded systems, devices, or machines. Computer vision involves teaching machines to interpret and understand...

environmental chamber

A test chamber designed to expose the subject being tested to external conditions, such as heat, shock, pressure and moisture, for the study of their effects.

f number (f/#)

The expression denoting the ratio of the equivalent focal length of a lens to the diameter of its entrance pupil.

footlambert

Unit of luminance equal to 1/p candela per square foot. (fl).

Fresnel number

In a lens, the square of the radius of its aperture divided by the product of the focal length and the wavelength. It measures the importance of diffraction in the image formed by the lens. A small...

Grashof number

Formula used in convection study to express the ratio of buoyant force to viscous force.

high-pressure cloud chamber

A cloud chamber designed to maintain the gas within it at a high pressure as a means of reducing the range of the high-energy particles and, subsequently, increasing the chances of observing...

imbedding material

A thermoplastic or thermosetting material used to hold an object fixed and keep it from deterioration. In microcircuitry, the process of imbedding is known as potting.

ionization chamber

A closed vessel with electrodes of different potentials that is used to determine how much ionization took place in a gas after its exposure to x-rays or radioactive emissions.

Lambert's absorption law

Transmittance of a solution, or internal transmittance of a transparent solid, is an exponential function of the thickness of the layer.

Lambert's cosine law

Flux per unit solid angle leaving a surface in any direction is proportional to the cosine of the angle between that direction and the normal to the surface. A material that obeys Lambert's cosine...

lambert

A unit of luminance equal to 1/p candela per square centimeter. (l).

lambertian

Obeying Lambert's cosine law.

lambertian emitter

An optical source that has a luminous distribution that is uniform for all directions.

lambertian source plane

In optics, a plane that emits a flux proportional to the cosine of the angle of the normal; dense opal glass is an example.

lambertian surface

A perfectly diffusing surface; the intensity of the light emanating in a given direction from any small surface component is proportional to the cosine of the angle of the normal to the surface. The...

member

In a lens system, a group of elements considered as an entity; either a front or rear member depending on whether it is before or after the aperture stop.

MOMBE

metallorganic molecular beam epitaxy

Nusselt number

Expression of the nondimensional coefficient of the heat transfer in a convection process.

Prandtl number

Ratio of the molecular diffusion coefficients of momentum in terms of heat; used in convection studies.

strength member

A strand of aramid yarn, steel or fiberglass in an optical cable intended to prevent bending or stretching that would damage the transport medium.

t number

The equivalent f number of a fictitious lens that has a circular opening and 100 percent transmittance, which would give the same central illumination as the lens being considered: where...

t-number

transmission number

television line number

The value equal to the raster height divided by the half-period of a periodic test pattern.

V-number -> normalized frequency

Also referred to as the V number in fiber optics; the normalized frequency is a dimensionless quantity, denoted by the symbol V, given by: where a is waveguide core radius, l is wavelength in vacuum,...

vacuum chamber

A vacuum chamber is a sealed enclosure from which air and other gases are removed to create a low-pressure environment, typically close to or at a complete vacuum. These chambers are often...

wave number

The frequency of a wave divided by its velocity of propagation; the reciprocal of the wavelength.

Bouguer's law -> Lambert's absorption law

Transmittance of a solution, or internal transmittance of a transparent solid, is an exponential function of the thickness of the layer.

cosine emission law -> Lambert's cosine law

Flux per unit solid angle leaving a surface in any direction is proportional to the cosine of the angle between that direction and the normal to the surface. A material that obeys Lambert's cosine...

potting -> imbedding material

A thermoplastic or thermosetting material used to hold an object fixed and keep it from deterioration. In microcircuitry, the process of imbedding is known as potting.

T stop -> t number

The equivalent f number of a fictitious lens that has a circular opening and 100 percent transmittance, which would give the same central illumination as the lens being considered: where...

absolute (kelvin degrees), absorption, acoustic, alpha particle, analog, anode, ampere, amplitude, area, atomic, atomic mass, Helmholtz free energy, mass number, nucleon number

abridged spectrophotometer

An instrument that uses optical filtration in order to measure the transmittance for a discrete range or specific number of wavelengths.

actinide

Any of a series of radioactive elements with atomic numbers ranging from 89 to 103.

activity

1. Synonymous with radioactivity. The intensity of a radioactive source illustrated as the number of atoms disintegrating in unit time, or as the number of scintillations or other effects observed...

addressability

In display technology, an expression of resolution given by the number of pixels in both the horizontal and the vertical axes of a cathode-ray tube or similar device.

air bearing

A support device in which a column or chamber of air permits the free travel of a mobile part. In optical mounting and positioning equipment, air bearings are of two types, linear or rotary,...

alignment telescope

An optical tooling instrument consisting of an objective lens, a focusing lens, an optical micrometer, a reticle and an eyepiece. The alignment telescope projects a precise line of sight to which a...