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Laser diode from CD-RW igniting matches

     I have developed an improved power supply for laser diode - current stabilizer with the circuit 7805. With 33R resistor it gives about 155 mA current. The current is calculated according to the formula: I = 0.005 + (5 / R). The current is determined by that the resistance has 5 volts accross it, therefore, current can be calculated according to Ohm's law. The quiescent current of 7805 from the "ground" pin, should be added, which is 5 mA (0.005A). 7805 stabilizer requires adequate heat sink. Supply voltage is about 10 - 30V. (The voltage does not affect the current.) At higher voltages 7805 heats more. The current source can also be created with LM317 circuit, see diagram below.
     focused beam of laser diodes from CD-RW with a 155 mA supply can light a match within 1-3 seconds.

Class IIIb laser

     Warning! Laser diodes from CD-RW emit invisible laser radiation and they are very dangerous! Their light can permanently damage the eyes. You must never look into the working diode even without the lens or point it on a reflective surface. Laser beam can cause burns or fire. This is usually a Class IIIb laser. Everything you do at your own risk.

The schematic of the simple current supply for laser diode.

Laser igniting the matches.

You can download the laser videos in the videos