Remote control technology, also known as remote control technology, refers to the realization of remote control of the controlled target, and is widely used in the fields of industrial control, aerospace, and home appliances. Infrared remote control is a wireless, non-contact control technology. Because infrared remote control devices have the characteristics of small size, low power consumption, strong functions, and low cost, after color TVs and video recorders, tape recorders, audio equipment, air-conditioners and toys, etc. Infrared remote control is also used on other small electrical devices. In the environment of industrial equipment, toxic gas, dust, etc., the use of infrared remote control is not only completely reliable but also effective in isolating electrical interference, and it is increasingly being applied to computer systems.
This intelligent infrared remote control output system can not only remotely control various domestic remote control devices with infrared receiving, but also has a special function, and can also remotely control other electronic products produced by members of AEHA (Associate for Electric Home Appliances) in Japan. Through software control, the remote control output system can output all remote control waveforms required by AEHA.
system design
1 Infrared
Infrared is one of the many invisible rays in the sun’s rays. It was discovered by British scientist Herschel in 1800. It is also called infrared heat radiation. He uses a prism to split the sun’s rays into different colors. A thermometer was placed on the belt to try to measure the heating effect of various colors of light. It was found that the thermometer outside of the red light heats up the fastest. Therefore, it is concluded that in the solar spectrum, there must be invisible light outside the red light. This is infrared light, which can also be used as a transmission medium. As shown in Figure 1, in the solar spectrum, the wavelength range of light waves is 0.01 μm to 1000 μm. According to the different wavelengths, it can be divided into visible light and invisible light. Light waves with a wavelength of 0.38μm～0.76μm can be visible light, followed by seven colors of red, orange, yellow, green, blue, blue and purple. The light wave of 0.01 μm to 0.38 μm is ultraviolet light (line), and the light wave of wavelength of 0.76 μm to 1000 μm is infrared light (line). The wavelength of infrared light is greater than that of visible light. Infrared can be divided into three parts, namely, near infrared, mid-infrared, and far-infrared. Infrared can be used as infrared level meter, infrared telescope, infrared speedometer, infrared perspective mirror and infrared remote control. Infrared remote control uses near-infrared light to transmit remote control commands, with a wavelength of 0.76 μm to 1.5 μm. Near-infrared is used as the remote control light source because the peak wavelengths of the current infrared emitting devices (infrared light-emitting tubes) and infrared receiving devices (photodiodes, triodes and photocells) are generally 0.8μm～0.94μm, which are in the near-infrared light band. , The spectra of the two coincide exactly, and they can be matched well. Therefore, higher transmission efficiency and higher reliability can be obtained.
