Laser Diode Circuit

Time : Feb 17 2015Source :analogtechnologies Author : Analog Click :

A laser diode is a diode which outputs a laser beam.

    Unlike LED light, a laser's light output is more concentrated, meaning it has a smaller and more narrow viewing angle. This means it must be directed at its source more directly in order to be picked up. Laser light is also monochromatic, meaning laser light isn't composed of several lights combined together, but one light of the same wavelength and energy. Normally with LEDs, the different light outputs are based upon different colors combined. One such example is green light. To output green light, blue and yellow lights are combined to give green. Lasers, for the most part, do not follow this. Laser lights have a single spectral color and is almost the purest monochromatic light available.

    Laser diodes are used in CD players, CD-ROM drives, and other optical storage drives. They are used in laser printers, laser fax machines, laser pointers, measurement equipment, bar-code and UPC scanners, and in high-performance imagers, as well as various other applications. These are just the most popular and used aspects of them.

To build a laser diode circuit, we must create a driver circuit for the laser diode.

    A driver circuit is a circuit which can limit appropriately the amount of current being fed into the laser diode, so that it can function correctly. Too much current and the laser diode will blow. Too little current and the laser diode will not have sufficient power to turn on and operate. Therefore, a driver circuit is needed to give precisely the correct range of current needed so that our diode will operate.

    To build the driver circuit, we are going to need a voltage source, a voltage regulator, a diode, an electrolytic capacitor, and a few resistors.