Mario Smart tv box Infrared remote control
The main part of the launch part of the infrared light-emitting diodes. It is actually a special light-emitting diode. Because of its internal material is different from ordinary light-emitting diodes, when a certain voltage is applied to both ends, it emits infrared rather than visible light.
A large number of infrared light-emitting diodes emit infrared wavelength of about 940nm, the same shape and ordinary light-emitting diodes, but different colors.
Infrared light-emitting diodes are generally black, dark blue, transparent three colors.
The luminous efficiency of infrared light-emitting diode using a special instrument can be accurately measured, while the amateur condition can only be roughly determined by the pull-away method. The receiving part of the infrared receiver tube is a photodiode.
In practice, to give the infrared receiver diode plus reverse bias, it can work, that is, the infrared receiver diode is used in the reverse circuit, so as to obtain higher sensitivity.
As the infrared light-emitting diode transmit power is generally small (15mW or so), so the infrared receiver diode receives the signal is relatively weak, it is necessary to increase the high-gain amplifier.
The common carrier frequency for infrared remote control is 38kHz, which is determined by the 455kHz ceramic oscillator used by the transmitter.
Infrared remote control is characterized by no impact on the surrounding environment, does not interfere with other electrical equipment. Because of its inability to penetrate the wall, so different rooms of the household appliances can use the universal remote control without mutual interference; circuit debugging is simple, as long as the given circuit is connected correctly, generally without any debugging can be put into work; Codec Easy, multi-channel remote control.