Friday, June 5, 2009

Infrared

Unguided infrared and millimeter waves are widely used for short- range communication. The remote controls used on televisions. VCRs and stereos all use infrared communication. They are relatively directional, cheap and easy to build but have a major drawback. they do not pass through solid objects. In general, as we go from the long wave radio toward visible light, the waves behave more and more like light and less and less like radio.

On the other hand, the fact that infrared waves do not pass through solid walls well is also a plus. It means that an infrared system in one room of a building will not interfere with a similar system in adjacent rooms or buildings; you cannot control your neighbor's television with your remote control. Furthermore, security of infrared system against eavesdropping is better than that radio systems precisely for this reason. Therefore. no government license is needed to operate the ISM bands. Infrared communication has a limited use on the desktop, for example, connecting notebook computers and printers, but it is not a major player in the communication game.

Infrared is located in the components catagory in system information. It contains information about infrared (IR) devices and ports on your system. These devices may not exist on all machines.

Infrared communication

Infrared communication uses infrared ( Light that is beyond red in the color spectrum, while the light is not visible to the human aye. infrared transmitters and receivers can send and receive infrared signals) light to transfer data.

Infrared light is also used almost universally by TV and VCR remote controls. In computers, infrared communication offers an alternative to cables and floppy disks. Infrared communication provides a point-to -point, low-cost way to connect computers with each other or with devices and appliances. Many celluar phones are equipped with infrared ports that allow them to be connected to a computer for dial-up-networking connections.


long range security system device


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