Infrared Remote control, an ancient technology that still exists today

Electronic equipment such as television, radio tape, VCD player, DVD player, or air conditioner (AC), can now be confirmed to be equipped with a remote control. With remote control, we can adjust TV such as changing channels or changing volume from our sitting position without need to go and press buttons on the TV.

Although most people currently limit understanding of remote control to home electronic equipment, its function is actually much broader. As the name implies, a remote control is a remote control device that functions to control an electronic object remotely. The controlled object will then respond according to type of instruction it gives. Instructions are given by pressing appropriate button on remote control. Currently, remote control is used for various purposes, from changing temperature of air conditioner to controlling motion of robot.

The way remote control works is similar to how Morse code is sent via a telegraph machine. A sending operator sends a short text message to a receiving operator who is at a certain distance. However, message is sent in form of a Morse code pattern that represents letters in message it sends. Telegraph machines use certain codes because they cannot transmit voice data like telephones. But telegraph can send an electric current that is connected to a bell at receiver, so that receiving operator will receive sound from bell in certain patterns which, when assembled, can be translated as short messages.

Remote control uses an infrared LED (Light Emitting Diode) which functions as a transmitter of infrared light patterns. Infrared LED is a kind of small lamp that has a diode that will emit infrared light when given an electric current.

Infrared signal that is sent cannot be seen by our eyes, because infrared rays are not included in electromagnetic waves in visible light spectrum. However, beam can be read by receiver on electronic equipment that receives signal. Receiver used is an infrared photo transistor. If received infrared signal pattern corresponds to one of instructions, such as an instruction to increase volume on television, volume of television will be increased. If infrared ray pattern that is read cannot be recognized, television will ignore it. This may happen if a remote control for other equipment that is not far from television is being used. Form of signal code for each button depends on electronic equipment manufacturer. Basically each company is free to define signal code for each button on remote control.

Use of this infrared ray signal is only suitable for indoor use, such as for home or office electronic equipment, because apart from having a short distance limitation (a maximum of about 10 meters), transmission angle is also very small so that remote control must be directed to right direction to electronic device. Infrared rays also cannot penetrate the walls, so they must be in room.

But now it has developed, many types of remote control use the bluetooth feature or take advantage of an internet connection. So it has a wide scope, so it can really control electronic objects from very far distances, without space restrictions.

Thank you for taking time to finish reading this article, I hope it is useful and adds to your insight.