Photonics Dictionary

A continuous strobe, also known as a continuous light or constant light strobe, is a type of lighting device used in photography, videography, and various other applications where continuous...

An early type of nonvacuum photocell consisting of a layer of copper oxide on a metallic substrate, with a thin transparent layer of a conductor over the oxide. When light falls on the cell, a small...

A rangefinder on a camera that is integrated with the focusing mechanism so that when an object's range is determined, the camera is automatically in focus.

A frame taken to identify electronic noise in a CCD imaging device. A dark frame is recorded without exposing the CCD to any external light by, for example, leaving the shutter of a CCD camera...

Diamond turning refers to a precision machining process used to produce complex optical components, particularly lenses and mirrors, from materials such as metals, plastics, and crystalline materials...

1. An optical device used for projection of enlarged images of transparencies or lantern slides on a screen. 2. A device designed to hold and backlight transparencies so that their images can be...

A dichroic mirror, also known as a dichroic beamsplitter or interference filter beamsplitter, is an optical device that selectively reflects or transmits light based on its wavelength. Dichroic...

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...

An embossed or marked disk, constructed out of a transparent material and used with a camera system to soften an image.

The scanning of photographs or transparencies of images, either by a vidicon camera or flying spot scanner, for the conversion of the images to digital form for storage on magnetic tape.

A form of photography in which an electronic camera converts an image to an electronic signal that is stored in digital format on magnetic media or film.

A scanning technique in which the object is illuminated the entire time, and in which picture elements of the object are viewed singly by the television camera.

In a camera, the focusing of an image on the screen located at the camera's film plane. Once the image is in complete focus, the recording medium is inserted in place of the screen.

Dispersion refers to the phenomenon where different wavelengths (colors) of light travel at different speeds when passing through a medium. This variation in the speed of light for different colors...

A fast, wide-angle lens used in television and photographic cameras, with excellent overall correction, but subject to residual oblique spherical aberration.

The photographic recording of images produced by the electrons from an electron microscope. The electron beam carries the images through an array of three lenses, and an enlarged electron image is...

1. A device generally used in a cathode-ray or camera tube to emit a stream of electrons moving at uniform velocity in a straight line. It consists of an emitting cathode and an anode, with an...

A small television monitor that replaces the reflex viewfinder in a television camera.

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...

Emission spectroscopy is a technique used to study the emission of electromagnetic radiation (light) by atoms, molecules, or ions when they undergo transitions from excited states to lower energy...

The photographing of objects within generally inaccessible areas using endoscopes with camera attachments.

Etaloning is an optical phenomenon that occurs in imaging systems, particularly in devices such as spectrometers, interferometers, and cameras. It is characterized by the appearance of interference...

An event-based image sensor, also known as a dynamic vision sensor (DVS), is a type of digital imaging device designed to capture visual information in a highly efficient and unique way compared to...

An instrument used to measure the light from a scene to be photographed and to indicate the camera lens and shutter settings required to expose the film correctly. The exposure time required in a...

The field of view (FOV) refers to the extent of the observable world or the visible area that can be seen at any given moment through a device, such as an optical instrument, camera, or sensor. It is...

The site behind the lens system in a camera where photographic media are positioned for exposure.

A mechanism in a camera designed to position the film in the focal plane for exposure.

A frame taken with a CCD camera of a surface that is evenly illuminated by diffuse light. This frame shows irregularities in the light-sensing ability of the CCD, such as electronic defects and dust...

A lens having an extremely high aperture and used in the recording of x-ray fluorescent screen images. It often is specially designed for the camera, the color of the light and the image...

A shutter having one or more roller blinds of material with a variable slit that moves across the back of the camera when released and exposes the sensitized material progressively.

1. The focal point. 2. To adjust the eyepiece or objective of a telescope so that the image is clearly seen by the observer. 3. To adjust the camera lens, plate, or film holder so that the image is...

The Foucault test is performed by moving a knife edge laterally into the image of a small point source. The eye, or a camera, is placed immediately behind the knife edge, and the exit pupil of the...

A frame grabber is a hardware device or interface card that connects to a computer or imaging system and is designed to capture and digitize frames of video or images from a video source such as a...

The number of separate images exposed by a cine camera in a second or the number illuminated by a cine projector in a second. By varying the number of images recorded per second, films can be created...

Freeform optics refers to the design and fabrication of optical surfaces that do not follow traditional symmetric shapes, such as spheres or aspheres. Unlike standard optical components with...

A Fresnel lens is a type of optical lens that consists of a series of concentric grooves or steps carved into a flat, thin piece of transparent material, typically plastic or glass. This design...

Modification of a system to provide for a linear transfer characteristic from an input to an output device. A circuit for this purpose is built into a television camera to compensate for display tube...

A device used to lock the internal synchronization generator of a television camera to an external source.

GigE, short for gigabit Ethernet, refers to a standard for high-speed Ethernet communication, capable of transmitting data at rates of up to 1 gigabit per second (Gbps), or 1000 megabits per second...

Gyroscopy refers to the principles and applications of gyroscopes, devices that measure or maintain orientation based on the principles of angular momentum. Gyroscopes are essential in various...

High dynamic range (HDR) refers to a technology that allows for a broader and more dynamic range of luminosity in visual content, such as images or videos. It is particularly associated with displays...

Photography involving the recording of events that occur too fast to be perceived by the human eye or recorded by conventional photographic techniques. See high-speed movie camera; high-speed...

That object distance at which a camera must be focused so that the far depth of field just extends to infinity. The near limit of the depth of field is then half the hyperfocal distance. For normal...

A type of stereoscopic photography in which the distance between the two view points is greater than the average interpupillary distance. Therefore, the viewed image will appear to be half its size...

A camera tube that employs a high-velocity electron beam to scan a photoemissive mosaic and to store electrical charge patterns.