How to connect a laser diode
How to connect a laser diode
Laser diode different from lightdiodebut a very small area of the crystal. This results in a significant power concentration, so even a short-time current excess through the junction diodeand can lead to the burning of a crystal not by heat, but by its own radiation.
Instructions
1
The most convenient for conducting experimentsa red laser with an output power of about 200 milliwatts, available in every computer burner for DVDs. Take the drive with worn out mechanics, which is no longer usable for its intended purpose. After making sure that the device is de-energized and connected to nothing, disassemble it and remove two laser diodea.
2
Both diodebut check in action. To do this, by pointing the lens of the device away from you on a sheet of paper, connect the battery to it from the motherboard (not necessarily a new one, but half-discharged). The laser has three outputs, two of which are connected together - they are negative, the remaining output is a plus. Select the one from the two diodewhich will illuminate the sheet with bright and richin red. The second device is infrared. Weak red radiation in it - the secondary, the intensity of the infrared is much higher, so it also can not be directed into the eyes.
3
The laser, which turned red, is set tohomemade radiator. To do this, in an aluminum plate with a thickness of about 4 mm, drill a hole of this diameter so that the device enters tightly into it. Between the body diodeand apply a thin layer of thermal paste to the radiator.
4
Take a ceramic wire resistor with a resistance of 20 ohms and a power of 5 watts. Such resistors are, in particular, in old Mustek scanners. Observing the polarity, connect diode to the charger from the cellular phone through this resistor. The laser itself is shunted with a ceramic capacitor of any capacity.
5
Turn the laser away from you, turn on the chargerdevice into the network. The light will appear. Try using a flat convex or biconvex lens to focus it on a sheet of low-melting material that absorbs red color (for example, black or dark blue plastic). Hold him a few seconds at one point, and in the place of his hit there will be a trace.
6
Spectacular experience with laser diodecan be carried out as follows. Take a thin rubber ring (sets of such rings are sold in stationery stores). Tightly wind the ring with a large diameter felt pen. A small section of the ribbon is painted black with another felt-tip pen. Focus the laser at this point, and after a few seconds you will burn the ring, and the marker will jump slightly. Naturally, it is not the light energy that makes it jump, but the kinetic energy of the stretched rubber ring, but the audience can be told about it only after the demonstration.
