LED (Light Emitter Diode) (shown in Figure 1) is one kind of diode that using side effect of operating diode. In common diode, this side effect is released as a heat energy. But in LED this side effect is used for light emitting. Because of this, then LED has a new function as indicator. This indicator can give us an information about binary or other number system (decimal or hexadecimal) also character by arranging LED in dot matrices.
Figure 1. Various Color of LEDs
In binary system, LED indicate a bit, but in decimal or hexadecimal, LED must be arranged in certain configuration, such as seven segment (shown in figure 2) or alphanumeric. There are many color and dimension of seven segment LED display. The price of seven segment LED display increase with the increasing of dimension. So if we will use a seven segment LED display which it dimension is about 4 x 8 inch, the price is so expensive if be compared with 0.5 x 1 inch Seven segment LED display.
Figure 2. Seven Segment LED display
When we are facing with this problem we can reduce the price by assembling to construct this component, like a product that shown in figure 3.
Figure 3. Big Dimension Seven Segment LED Display, by arranged LEDs