红外遥控基础知识（Basic knowledge of infrared remote control）.doc

红外遥控基础知识（Basic knowledge of infrared remote control） Time: January 3, 2006: Toy Design Forum Infrared remote control, before talking about infrared remote control, first of all to talk about what is infrared. We know that visible light can be seen from long to short, followed by red, orange, yellow, green, cyan, blue and purple. The wavelength range of red light is from 0.62 to 0.76 m, and the wavelength range of violet light is from 0.38 to 0.46 M. The light that is shorter than violet light is called ultraviolet light, and the light that is longer than the red wavelength is called infrared ray. Infrared remote control is to use the wavelength of 0.76 ~ 1.5 m between the near infrared to transmit control signals. Infrared remote control system commonly used infrared remote control system is generally divided into two parts of transmission and reception. The main part of the emission part is infrared led. It is actually a special light-emitting diode, because its internal material is different from the ordinary light-emitting diode, so when the two ends of its application of a certain voltage, it is issued by infrared light, not visible light. At present, a large number of infrared light emitting diodes emit infrared wavelengths of about 940nm, the shape of the same as ordinary 5 light-emitting diodes, but the color is different. Infrared LED generally has black, dark blue, transparent three colors. The method of judging the quality of an infrared LED is the same as that of an ordinary diode: the resistance of the infrared LED can be measured by the resistance of the multimeter. The luminous efficiency of infrared LED can only be measured accurately by special instrument, but only by pull distance method in amateur condition. The receiving section of the infrared receiving tube is a photosensitive diode. In practical application, the infrared receiving diode is added with reverse bias, so that it can work normally. That is to say, when the infrared receiving diode i