Photodiode Process Essay Example for Free

Photodiode Process Essay* a type of photodetector capable of converting light into all current or voltage, depending upon the mode of operation. The common traditional solar cell used to generate electric solar power is a large sector photodiode.* a semiconductor with a p-n junctionPRINCIPLES OF PHOTODIODE* Photons is the source of its energy* Energy can be solved by the comparisonW=hfWhereh =Plancks constant= 6.62410-34f = frequency* The frequency is, in turn, directly related to the wavelength (distance between successive peaks) of the traveling wave by the following equation = Vf= wavelengthf = frequencyV = velocity of light* 1 lm=1.49610-10 W* Light intensity is measured in lmft2, footcandle (fc), or Wm2 * The operation of the photodiode is hold to reverse bias region. * The application of light allow result to the transfer of energy(photons) * Dark current current that will exist without illumination.APPLICATIONS* employed in an dread system.* reverse will continue to fl ow as long as the light beam does not broken* used to count items in the car transporters belt.* item passed the light beam then it will be broken the current will drops to the dark current level and the counter will increase.PHOTOTRANSISTOR* A photoelectric device with photosensitive collector- report p-n junction. The current induced by photoelectric effects is the base current of the transistor.PRINCIPLES OF PHOTOTRANSISTOR* If we assign the notation I , for the photoinduced base current, the resulting collector current, on an approximate basis isIchfe I* An increase in light corresponds with the increase in collector current.APPLICATIONS* Punch-card readers* Computer logic circuitry* visible light control* Level indication* Relays* Counting systems* High isolation AND gate using three phototransistors and three LED as is aid. * The high isolation patently refers to the lack of an electrical connection between the input and output circuits.