enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Opto-isolator - Wikipedia

    en.wikipedia.org/wiki/Opto-isolator

    Schematic diagram of an opto-isolator showing source of light (LED) on the left, dielectric barrier in the center, and sensor (phototransistor) on the right [note 1]. An opto-isolator (also called an optocoupler, photocoupler, or optical isolator) is an electronic component that transfers electrical signals between two isolated circuits by using light. [1]

  3. Photoresistor - Wikipedia

    en.wikipedia.org/wiki/Photoresistor

    Three photoresistors with scale in mm Large CdS photocell from a street light. A photoresistor is less light-sensitive than a photodiode or a phototransistor. The latter two components are true semiconductor devices, while a photoresistor is a passive component that does not have a PN-junction. The photoresistivity of any photoresistor may vary ...

  4. Resistive opto-isolator - Wikipedia

    en.wikipedia.org/wiki/Resistive_opto-isolator

    Opto-isolator VTL2C1 with LED input and photoresistor output. Resistive opto-isolator (RO), also called photoresistive opto-isolator, vactrol (after a genericized trademark introduced by Vactec, Inc. in the 1960s), analog opto-isolator [notes 1] or lamp-coupled photocell, [1] is an optoelectronic device consisting of a source and detector of light, which are optically coupled and electrically ...

  5. Photoelectric sensor - Wikipedia

    en.wikipedia.org/wiki/Photoelectric_sensor

    Conceptual through-beam system to detect unauthorized access to a secure door. If the beam is interrupted, the detector triggers an alarm. A photoelectric sensor is a device used to determine the distance, absence, or presence of an object by using a light transmitter, often infrared, and a photoelectric receiver.

  6. Twilight switch - Wikipedia

    en.wikipedia.org/wiki/Twilight_switch

    A twilight switch is an electronic component that allows the automatic activation of a lighting circuit when natural light drops in a given environment. Among a large number of uses, the most common is to enable automatic lighting of streets, roads, highways, roads, gardens, courtyards, etc., when sunlight drops below a certain level (e.g.: a ...

  7. Mechanical television - Wikipedia

    en.wikipedia.org/wiki/Mechanical_television

    Nearby photocell pickup units convert the reflected light to a signal proportional to the brightness of the reflected area, which goes through the control board to the transmitter. The BBC television service used the flying spot method until 1935, and German television used flying spot methods as late as 1938.

  8. Photomultiplier tube - Wikipedia

    en.wikipedia.org/wiki/Photomultiplier_Tube

    The work was submitted for print publication only two years later, in July 1936 [11] as emphasized in a recent 2006 publication of the Russian Academy of Sciences (RAS), [12] which terms it "Kubetsky's Tube." The Soviet device used a magnetic field to confine the secondary electrons and relied on the Ag-O-Cs photocathode which had been ...

  9. Photodetector - Wikipedia

    en.wikipedia.org/wiki/Photodetector

    A photodetector salvaged from a CD-ROM drive.The photodetector contains three photodiodes, visible in the photo (in center).. Photodetectors, also called photosensors, are sensors of light or other electromagnetic radiation. [1]