This project consists of three different lasers, red (650nm), green (532nm) and violet (405nm). The lasers are produced and projected through some interference filters, known as dichroic mirrors.
The function of the filters is to reconfigure the wave length of the light that goes through it. But, they must be alligned in a very particular and precise manner. Because as it filters some of the lasers, the others pass through. Each laser has a proper mirror to produce the image.
In order to align the mirrors precisely, there are some special tools called Kinematic Mount, which, by the way, can be made at home. The handles regulate the position in both axis by using two different screws.
The red laser beam is produced using a DVD laser diode. For the green laser beam a CD laser diode is used. Finally, the violet laser beam is produced by a BluRay diode reader. All of these generator require an independent power source which must be chosen properly as a mistake on this can result in total failure.
Finally, all this is attached to an optical scanner that sends the appropriate signals to the laser diodes and filters. The desired image is produced through an interface software operated in a computer.
All of the components are placed inside an aluminum case along with switches, connectors, LED display and a potentiometer to regulate the size of the image, making a compact and efficient projector.