O-like Green Labbie

I was recently lucky enough to acquire one of the green labbies which Matt ( Mohrenberg) got from ebay. There are no part numbers on it and Matt assures me that is was originally from O-like --- No power ratings known.

Specs:

Laser head: 1.8" wide x 1.18" high x 3.42" long including fan
Pwr.Supply: 2.0" wide x 1.83" high x 4.34" long Much of this is heatsink
Input power: 130 VAC - 60 Hz
Modulation Port: TTL

The 12" cable between the PS and head has 8 large wires indicating that the head is likely TEC cooled. The power supply has two exposed 10 turn pots which I have not tried yet but I'm assuming control LD current and TEC setting. The Modulation port is a minature two pin plug and from testing is TTL as there appears to be no analog slope.

The laser powers up and stabilizes at ~150 mW after 20 seconds. I went to get a power measurement head and when I came back, a screwdriver handle was smoking!! Yes it has power.

This is all I know so far - I haven't measured divergence because weather here is getting bad :-( but the beam looks tight.



HMike

sweet! i want one too!

OK - Then go buy one. It's that simple. or is this for count?

HMike


Untested observation: The TTL input appears "visually" to have a soft start feature which may limit its use in projos.

Very nice

Sgt -- I'm not giving you any more pictures -- You would likely build something better !!!!
Just Kidding!!! This thing runs coollllll . The fan also seems to be controlled by the PS and remains stable at ~150 mW.

HMike

Also for projo use, the head appears to be electrically isolated from ground so we don't have to worry about the + case driver.

I have several of those, and I think they're the best deal around currently for a TEC-stabilized green. The modulation response can be a little rough, but i don't expect too much from inexpensive Chinese..

Here's a link to the unit on o-like's website. They're rated at 100mW.

EF --

There seems to be an RC circuit in the TTL driver circuit which makes modulation a little slow. Also, what are the two 10 turn pots on the top board ued for?

HMike

Only guessing here, but I would imagine one is TEC current and the other is diode current. In my experience, that's pretty much the standard configuration.. I might have to try fiddling with one of mine.

So far, VR1 is LD current and VR2 is TEC.
VR1 has the most power control. It's slow to watch TEC effect.

HMike

Turning VR2, I assume TEC, CCW a little seems to let the power increase slowly. This may be over cooled. At a room temp of 67 Deg F, the laser housing is running at 73 Deg and the fan housing at 74 Deg. This using an IR temp meter.

Were you able to get any gains?

Gains? -- Please define.
I've noticed that if I use the TTL to shut off the beam, The module may over cool in idle mode which cuts power until it warms up again which takes time.

HMike

Sorry, I thought you were temp tuning it when you were messing with the pots, but you never said that was what ou were doing, so I may have assumed when I shouldn't have..

VR1 is the obvious power control. VR2 appears to control the TEC and it's hard to adjust because of time lag and variables like that.

HMike

A couple of mine do the same thing you were saying about the laser over-cooling when it's blanked for a bit.. That's actually what I meant be the modulation being rough.. If you come to a blank frame sequence that's too long, the laser takes a second to come back up.. Mine are all perfectly stable when running CW, though.