Photoelectric devices

Photoelectric devices

Devices which give an electrical signal in response to visible, infrared, or ultraviolet radiation. They are often used in systems which sense objects or encoded data by a change in transmitted or reflected light. Photoelectric devices which generate a voltage can be used as solar cells to produce useful electric power. The operation of photoelectric devices is based on any of the several photoelectric effects in which the absorption of light quanta liberates electrons in or from the absorbing material. See Solar cell

Photoconductive devices are photoelectric devices which utilize the photo-induced change in electrical conductivity to provide an electrical signal. Photoemissive systems have also been used in photoelectric applications. These vacuum-tube devices utilize the photoemission of electrons from a photocathode and collection at an anode. See Photoconductive cell

Many photoelectric systems now utilize silicon photodiodes or phototransistors. These devices utilize the photovoltaic effect, which generates a voltage due to the photoab-sorption of light quanta near a pn junction. Modern solid-state integrated-circuit fabrication techniques can be used to create arrays of photodiodes which can be used to read printed information.

McGraw-Hill Concise Encyclopedia of Engineering. © 2002 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
This feature renders strong benefits for multifunctional photoelectric devices. Moreover, the active adoption of the metal oxide materials would provide the optical transparency and electrical excellence which are promising advantages for Si-based photoelectric applications.
Joel Stebbins, then director of Washburn Observatory, pioneered the use of photoelectric devices in astronomy.
Recently, significant work has been put forward to produce low-cost and highly efficient photoelectric devices using thin film technology imbibing the heterojunction concept.
Nanosilica has applications in ceramics, chromatography devices, electronic pieces, photoelectric devices, etc.
I also worked on a project that used 3M retro-reflective tape applied to cartons for detection by photoelectric devices to manage material flow and automatically trigger conveyor line sorting to warehouse staging areas and shipping docks.
The photosensitive device developed at Exeter contains no metals and is therefore completely transparent but, as it can detect light from across the whole visible light spectrum, it is as efficient at sensing light as other recently developed opaque photoelectric devices.
Papers from the conference present the latest research results and future directions in MEMS/nano-manufacturing technology, precision mechanical manufacturing technology, and manufacturing technology for photoelectric devices and semiconductors.
provisional patent applications covering novel materials for use in fuel cells and electrolysers; "key" technological elements important to the application of the company's proprietary "in-situ" manufacturing process for membrane electrode assemblies (MEAs) and cell stacks; and photoelectric devices.
Photoelectric devices detect smoldering fires before they reach a flaming condition.
Photoelectric devices. These more expensive detectors emit a beam of light recieved by a photocell.

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