Hey guys,
Received my tiny Osram OPS laser from eBay last week and managed to get it up and running. These things are tiny, real interesting piece of engineering. These aren't you're typical Nd:YAG/YVO4 green; they use a semiconductor chip pumped by an 808nm diode instead. The result is a very compact form factor and fantastic beam specs. Perfect TEM00, 0.3mm diameter at aperture (4-8mRad divergence) and up to 100mW or so output power. One of the nicest beams I've seen out of a solid state laser, arguably better than the beam from my old Coherent Compass 115M.
Here's what they look like (hand for scale):
And here's what's inside:
Note: The labels on this diagram are somewhat inaccurate. The LD is 808nm, the part labeled "DBR" is the OPS chip. Everything else should be fairly accurate.
I opted to buy one without the driver seeing as they were $40 cheaper, so I had to build my own. Not much is required, just ~450mA constant current for the diode and 1.5-2.0V for the crystal heater. Used a pair of LM317s. Decided to go with SMD resistors for the current setting so had to use 4 as a single 0805 wouldn't handle the power, the less holes I have to drill the better! Here's the result:
Schematic:
Board:
To make the PCB I used the toner transfer method:
Transfer wasn't the best, but it turned out good enough the first time so I rolled with it.
Board etched, toner removed and tinning added:
Components soldered (turns out I missed an SMD resistor, and left the indicator LED off because I didn't see a need for it in the end):
Etch was done using hydrochloric acid and hydrogen peroxide.
Mounted to a heatsink with flying leads and a little breakout board sort of thing. The leads from the driver were too thick to solder direct to the module, so I used this approach. AA battery for scale.
Light! Fired up perfectly the first time. Diode current is ~365mA.
Spot at the other end of my living room:
Obligatory beamshot and a closeup:
Hope you all enjoyed, feel free to ask any questions!
I like it!
