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Blue diode laser 1W 445nm

     Now I managed to get a blue laser diode with 1W output and wavelength of 445nm and 5.6 mm TO18 housing and optics for my powerfull blue homemade laser. This diode has a deep blue light, unlike diodes from blu-ray (BD-ROM, BD-R, BD-RE), which have a wavelength of 405nm and almost invisible violet light (on the borderline of visible and ultraviolet light).
     Power of the LD is many times higher than the diodes from a CD-RW and DVD-RW drives (burners). Optics with a diode quickly warms up. The diode is no longer the 10-20s too warm. I've found that the longer the operation will need better cooling. I mounted the optics on a big aluminium heatsink.
     Optics enables precise laser focusing by screwing lens in the "worm" with a fine thread. You can focus either to close point or to the parallel beam. Diode can be powered either through resistance of controllable sources (simple solution) or using the stabilizer with LM317T current source with voltage in the range 7-16V (better solution, as the current does not vary with the input voltge). LM317T circuit should be placed on the heatsink. The current is determined by resistor R1. Its value is determined by calculating R = 1.25 / I
     The laser diode is connected to a protective circuit made up of four components (marked in blue in the diagram). Capacitors and resistor protects against static charge diode, diode 1N4007 from the polarity reversal. This protective circuot should be connected to the diode immediately after unpacking it from its protective antistatic bag and antistatic foam. It should be removed from the diode. When handling, modifying or replacing the power supply, never disconnect the bare diode, but the diode with protective circuit on it. Seems, that the case is not connected with anything. It is necessary to connect the case to one of the poles, othervise the diode will be easily destroyed by electrostatic charge. I connected the case to the cathode. Connecting both terminals and case is also needed during soldering. Soldering time must be as short as possible. The diode must never be soldered without heat sink (metal housing)! Caution - electrostatic sensitivity of the diodes is much higher than in unipolar integrated circuits.
     I tested the diode at current of 960 mA. The diode has a very bright blue light and a visible beam. It burns the paper, plastics, fabrics, wood and so on. It is burning from a distance of many meters and the beam does not even have to be very well focused. Paper or plastic burn decently with beam diameter of 3mm. Setting the power above 1W (current over 960 mA) can significantly reduce the life or even lead to immediate destruction.

warning - laser radiation
Class IV laser

     Warning! Laser diodes emit visible laser radiation and are extremely dangerous! Their light can permanently damage or skin. Never look into the working diodes or aim it on glossy surfaces. Always wear safety googless. Use camera to observe laser. Laser beam can cause burns or fire. This is a Class IV laser. Laser should not be used for illegal purposes. Everything you do at your own risk and responsibility.

The schematic of the stabilized power supply and the simple dirty supply. I do not recommend to disconnect the bare laser diode (right vertical line). The left vertical line shows how to disconnect the current supply.

Parameter value unit
Case diameter 5.6 mm
Wavelength 445 nm
Nominal power output 1000 mW
Nominal current 960 mA
Maximal current 1400 mA
Threshold current 200 mA
Voltage drop at nominal I 4.45 V
Differential efficiency 1.36 mW/mA
Max. working temperature 55 °C
Lifetime 20 000 h
Lifetime in dude's hands :) 1 ns
Parameters of this blue laser diode

1W 445nm nichia casio laser diode pinout. I recommend to connect the case to one of poles, probably to "-". The case output is cut because the case is usualyy connected via heatsink.

Blue laser beam from my homemade laser.

One more photo of ultra bright visible beam.

Optics for those laser diodes dia 5,6mm (TO18)

Blue laser diodes 445nm 1W.

Laser diode and lens (this bare lens were not used, i used the ones in optics)

Blue laser diode 445nm 1W.

Laser diode and disassembled laser optics. The picture shows how it is all put together (except lens).

Laser diode without lens at reduced power.

Diode with lens, being focusing at reduced power.

Laser beam in the clear sky.

Laser beam in slight fog

Laser diode in optics and with additional heatsink.

Dirty current source

Laser burning cardboard

Laser burning wood

Beam penetrating two layers of plastic

Hole in plastic

Protective laser glasses (goggles). This one protects against wavelenghts 190 - 540nm and can therefore be used against 405nm violet laser (blu-ray), 445nm blue laser like this, and also against green DPSS 532nm. Suitable also as a protection against mercury vapor lamps or UV fluorescent lamps including UV-C disinfection germicidal 253.7 nm (254nm).

Video 1 - First test at Current 960mA, drop 4,45V. Laser ignites immediately 6 matches and then one burned match. Visible beam without smoke. It burns wood and sets paper on fire.

Video 2 - Laser at 1W. Current 960mA. Laser produces visible ray, burns holes into plastic and cuts isolation tape.

Video 3 - Laser from window. Warning - should never be pointed at any aircraft or used near airport!

Video 4 - Visible laser beam and mirror reflections

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Added: 15. 11. 2011