Photonics Dictionary

Referred to as SWCNTs, these cylindrical nanostructures composed of a folded sheet of graphene can be used as near-infrared markers for small animal multiplex imaging. Emitting at different...

A high-brightness, short-duration source in which low-pressure gas initiates the discharge to vaporize material from the tube wall, leading to a high-pressure discharge of ionized wall material.

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.

A cathode-ray tube having a screen that is coated on the back with a thin film of aluminum, which serves to intensify the propagation of light.

An analog method of moving a cathode-ray tube beam across a display screen face, commonly used in high-performance vector and character generators.

The part of an electrical circuit in which the electrons leave (a cathode-ray tube) or enter (an electrolytic cell) a unit in the circuit.

Also known as a shadow mask, a perforated plate placed between the focusing and accelerating electrodes, and the tricolor phosphor screen in a color-television tube.

In present usage, especially for spectroscopic identification, an arc between electrodes that serves as a radiation source. Gas tubes that contain mercury vapor and mixtures of helium, neon and argon...

In the discharge of a vacuum tube, the narrow, nonluminous region that sometimes may be found between the cathode and its glow.

An astronomical telescope is a type of optical instrument designed to gather and magnify light from distant celestial objects for observation and analysis. It typically consists of two main optical...

An electron-beam tube in which the current to an output electrode is regulated by the transverse motion of the tube's electron beam.

A device (e.g., prisms, lenses, tubes) used to align a beam in a system.

A beamsplitter is an optical device for dividing a beam into two or more separate beams. A simple beamsplitter may be a very thin sheet of glass inserted in the beam at an angle to divert a portion...

A dielectric ceramic material used in laser capillary tubes because of its high electrical resistivity and high thermal conductivity (half that of copper).

Also called proximity focus image intensifier. A compact image intensifier that utilizes a microchannel plate intensification stage. This is an in-line device that does not invert the image.

The process by which the raster beam in a video tube is cut off during the retracing and sync periods.

The loss of focus of a camera sensor because of excessive brightness, characterized by the enlargement of spot size and halation on a cathode-ray tube.

A technique developed by British Telecom in which the viscous drag of air is used to install optical fibers in narrow plastic tubes.

A thermometric instrument used for the detection and measurement of radiant energy. Its essential component is a short narrow strip covered with a dead black absorbing coating and mounted at the...

The central hole running the full length of a laser capillary tube, in which electrical discharge and laser action take place. Also a similar hole in a hollow waveguide or a microchannel plate.

A device for the internal inspection of hard-to-get-at mechanical parts, such as rifle barrels, sewer pipes, oil wells, or gas mains. The long narrow tube used contains a telescope system with as...

The manual shifting bias control of a cathode-ray tube that determines both the average brightness and the contrast of a picture.

The electron beam tube of a television camera that converts an optical image into a pattern of electrostatic charges and then scans the pattern to produce a corresponding electronic signal for...

The storage surface of an electron beam tube that is scanned by an electron beam to generate an output-signal current corresponding to the charge-density pattern stored.

A light-tight box that receives light from an object or scene and focuses it to form an image on a light-sensitive material or a detector. The camera generally contains a lens of variable aperture...

An image tube that functions in low-light-level conditions by virtue of its series of stacked sections wherein the output of one section becomes the input for the next.

An instrument consisting of a high-voltage vacuum tube used to form hard x-rays or high-speed ion beams. By partitioning the tube into separate sections, the total voltage is divided.

1. The negative electrode of a device in an electrical circuit. 2. The positive electrode of a primary cell or storage battery. 3. The primary source of electrons in an electron tube, serving as the...

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

The apparent luminosity or glow that immediately envelops the cathode in a gas-discharge tube operating at low pressures. The glow increases as the pressure decreases.

Cathode radiant sensitivity refers to the ability of a photocathode to convert incident radiant energy, typically in the form of light, into an electrical signal. Photocathodes are components used in...

The method of disintegrating the substance of the cathode by bombarding it with ions and depositing it on another electrode or electron tube envelope.

Also known as cathode rays. Formerly, this term described a stream of electrons emitted from the cathode of a gas-discharge tube during its bombardment by positive ions. It also describes any stream...

A cathode-ray tube, driven by a computer, that receives impulses of information from the computer and displays it in a series of lines, circles, curves or other graphic forms to be viewed by the user.

A term used in data processing to describe a cathode-ray tube that displays graphic or character data.

A plane that lies at right angles to the tube axis that has the deflection center.

Envelopes for cathode-ray tubes are made by blowing glass in the same manner as light bulbs. They have a fairly flat end face to carry the phosphor material applied internally.

A fiber optic end plate constructed by drawing a bundle of parallel fibers embedded in glass and cutting it into thin slices. These slices are assembled in a plane and heated to produce a...

A high-quality, narrow-angle lens of high aperture designed for low magnification in the recording of cathode-ray tube images.

The luminous trace formed on the cathode-ray tube screen by the motion of the electron beam.