LEDs for Illumination

CHAPTER 4: LEDs 61

Figure 4-7 An RGB LED test breadboard layout

used in specialist applications such as checking the authenticity of bank notes and making people’s white clothes light up in clubs.

Use these LEDs just like any other LED. They will have a recommended forward current and voltage and will need a series resistor. Of course, checking that they are working is trickier. Digital cameras are often a little sensitive to infrared and you may see a red glow on the screen.

Figure 4-8 An RGB test

LEDs for Illumination

LEDs are also finding their way into general household lighting. This has come about because of improvements in LED technology that have produced LEDs with a brightness comparable to incandescent light bulbs—well, they are getting there anyway. Figure 4-9 shows one such high-brightness LED. In this case, it’s a 1-W LED, although 3-W and 5-W LED modules are also available.