What is infrared and Where is it used?

If you watch TV, chances are you’ve been "beaming" or using Infrared devices  

for most of your life. The commands from the remote control to the TV  

travel on infrared light waves instead of through a cable. Actually, the  

first TV remote control was developed by Zenith Radio Corporation in 1950 

and was named "Lazy Bones." A few years later the first wireless TV remote 

controller "Flashmatic" was introduced. The first remote controls included 

buttons that turned the TV on and off. By the early 1980s, the industry 

incorporated infrared, or IR, remote technology into the devices. Today, 

remote controls are made for many other consumer electronics products, 

including VCRs, cable and satellite boxes, and home audio receivers.

Ninety-nine percent of all TV sets, VCRs and DVD players sold in the United 

States include remote controls! When you use your remote, you are sending a small
burst of invisible data (in the form of photons of precisely modulated infrared light) to the TV. 

You can’t see the light, because it lies in the frequency range just below 

that of visible red light.

Infrared is not to be confused with radio waves or sound waves, it is

basically a light wave and waves are made of energy. Light waves come in a 

continuous variety of sizes, frequencies and energies. The amount of energy 

in a light wave is proportionally related to its frequency. Light not only 

vibrates at different frequencies, it also travels at different speeds.

Light waves can move as fast as 186,000 miles per second (in a vacuum), 

which makes light the fastest phenomenon in the universe. Light waves slow 

down when they travel inside substances, such as air, water, glass, etc. 

They cannot pass through solid objects.

The instructions for remote control devices are translated from a digital 

pattern into electrical signals, and then sent in one direction, from the 

remote to the TV. Remotes are ‘send only devices’ or uni-directional. With 

the help of IR photodiodes the devices can "see" or detect the light that transmits

the data. The TV can understand the instructions because it has the 

circuitry to convert the signals back to the original digital pattern of the 

information. IrDA enabled devices can "communicate." They are 

bi-directional. The technology behind bi-directional communications 

between devices is very complicated, and this is why the IrDA was 

created.

Think of it this way; IrDA is a secure, low-cost, convenient cable 

replacement technology -excellent for many specific applications and 

environments. It continues to be developed by many talented and skilled 

individuals from hundred of companies who, over the years, have comprised

the Infrared Data Association!

IrDA’s Infrared is successful as a communications transport technology 

because:

• IrDA is inexpensive! Components cost pennies!
• IrDA is FAST (up to 16 mbps and soon to leap frog from 100 to 500 mbps).
• IrDA enabled devices consume less power (minimal drain of the batteries of the devices),
• IrDA Data is secure. Data being transmitted via infrared is very difficult to intercept or hack because it is directional (you choose where to send it). Your data is safe because it cannot go through walls or objects. Virtually eliminates eavesdropping by un-welcomed recipients! Perfect for applications where sireless payment transfers are needed. Such as buying a soda out of a vending machine, or paying for something in a retail (restaurants and stores) or mobile environment (i.e. toll booths).
• IrDA is safe, there is no harm to the eye as long as it is used correctly.
• IrDA requires conscious, deliberate connection and control! You aim and control where your data goes, and/or who receives it!
•  IrDA has Point to point, Peer-to-Peer range. Your data is close at hand! It is not broadcast or distributed long distance, or in a wide angle or range. The connection range is about one meter, and the angle is 30 degrees.
• IrDA is ubiquitous.  It is globally adopted and implemented in over 1/2 billion products throughout the world. 
• IrDA standards are non-proprietary. Thus far they are free, which helps promotes adoption and makes possible interoperability across platform, brands, and product type if properly implemented.
• IrDA is relatively free from regulation. Infrared frequencies are just below the visible light on the electromagnetic scale so there is no restriction on anyone who wants to use them.
• IrDA has no radio frequency interference issues or signal conflicts. This is especially important in critical environments such as hospitals and airports.
• IrDA provides much improved security when used in financial applications. An IrDA enabled PDA or cell phone does not leave the consumers possession, the credit card account numbers are not publicly divulged, and the payment application itself is password and encryption protected.