Response wavelength range of silicon avalanche photodiode

The wavelength is below 370nm and the transmission depth is greater than 20nm. Silicon is one of the most ideal materials in the field of visible light detection, and it is also a common material for ultraviolet photoelectric sensing. The response of silicon material to ultraviolet light is low, because the transmission depth of ultraviolet light in silicon material is extremely shallow (the wavelength is below 370nm and the transmission depth is greater than 20nm). The carrier recombination effect leads to the rapid decrease of optical response with the decrease of incident light wavelength. Photodiodes are also used in consumer electronic products, such as CD players, smoke detectors and infrared remote control devices for controlling televisions and air conditioners. For many applications, photodiodes or other light guiding materials can be used. They can all be used to measure light, often work in the photometer of the camera, automatically adjust the brightness of street lamps and so on. All types of optical sensors can be used to detect sudden illumination or light emission in the same circuit system. Photodiodes are often combined with light-emitting devices (usually light-emitting diodes) into a module, which is usually called photoelectric coupling element. If so, the movement of external mechanical elements (such as photo-interrupters) can be analyzed by analyzing the received illumination. Another function of photodiode is to act as an intermediary between analog circuit and digital circuit, so that the two circuits can be coupled through optical signals, which can improve the safety of the circuit. In scientific research and industry, photodiode is often used to accurately measure light intensity because of its better linearity than other light guiding materials. Photodiodes are also widely used in medical applications, such as computed tomography (CT) and pulse detectors. PIN junction photodiode is usually not used to measure very low light intensity. But if the light intensity is large enough, avalanche photodiode, photosensitive coupling element or photomultiplier tube can all play a role, such as astronomy, spectroscopy, night vision equipment, laser rangefinder and other application products.