Building an Infrared transmitter device

Now that we have learnt how to build an IR receiver device, let us understand the basics of transmitting IR signals. For transmitting IR signals, we will have to use special IR Transmitter LEDs. IR transmitter LEDs come in various colors: blue, transparent, and so on. For the example in this section, we will use a blue IR LED.

Using an IR transmitter LED

The IR transmitter LEDs look similar to normal LEDs, but are slightly larger than the normal LEDs:

Figure 12: A typical IR transmitter LED

An IR transmitter LED has two legs (terminals) as shown in the preceding figure:

• Positive terminal (longer leg), this pin will be connected to the 5-volt power supply pin of the Arduino.
• Negative...