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Remote photoelectric sensors used for remote sensing contain only the optical components of a sensor. The circuitry for power input, amplification, and output switching is located elsewhere, typically in a control panel. This allows the sensor, itself, to be very small. Also, the controls for the sensor are more accessible, since they may be ...
Photodetectors, also called photosensors, are sensors of light or other electromagnetic radiation. [1] There are a wide variety of photodetectors which may be classified by mechanism of detection, such as photoelectric or photochemical effects, or by various performance metrics, such as spectral response.
An optical sensor converts light rays into electronic signals. It measures the physical quantity of light and then translates it into a form readable by an instrument. An optical sensor is generally part of a larger system that integrates a source of light, a measuring device, and the optical sensor. This is often connected to an electrical ...
PSDs can be divided into two classes which work according to different principles: In the first class, the sensors have an isotropic sensor surface that supplies continuous position data. The second class has discrete sensors in an raster-like structure on the sensor surface that supply local discrete data.
In quantum perturbation theory of atoms and solids acted upon by electromagnetic radiation, the photoelectric effect is still commonly analyzed in terms of waves; the two approaches are equivalent because photon or wave absorption can only happen between quantized energy levels whose energy difference is that of the energy of photon. [48] [17]
A photoelectric device can be either intrinsic or extrinsic. An intrinsic semiconductor has its own charge carriers and is not an efficient semiconductor (such as silicon is). In intrinsic devices, most of the available electrons are in the valence band, and hence the photon must have enough energy to excite the electron across the entire bandgap.
The passive-pixel sensor (PPS) is a type of photodiode array. It was the precursor to the active-pixel sensor (APS). [20] A passive-pixel sensor consists of passive pixels which are read out without amplification, with each pixel consisting of a photodiode and a MOSFET switch. [24]
2009 Nobel Prize in Physics laureates George E. Smith and Willard Boyle, 2009, photographed on a Nikon D80, which uses a CCD sensor. The basis for the CCD is the metal–oxide–semiconductor (MOS) structure, [2] with MOS capacitors being the basic building blocks of a CCD, [1] [3] and a depleted MOS structure used as the photodetector in early CCD devices.