Found a nice case in the trash!

[tocket]

I found this nice HP 9133 hard drive in the electronics junk at work and decided it might make a nice case for my 1W green. It appears to work well, but it's a damn tight fit (height) having the laser head on the upper level.

That thing used to be a 20 MB hard drive with GPIB interface and costed nearly $3k when it was released in 1985. While it's not worth much now, at least it's a solid case.

I'll probably have to replace the PSU as it only does 2.7A at 12V, which I figure won't quite cut it for a 1W DPSS laser. Luckily I have a nice little rack server PSU that does 12A and easily fits into that space. I still need to figure out where to put the galvo driver and PSU, but those are quite small as they're only 12K.

Now for the questions. I intend to install all the safety features required to run this projector at public events in Sweden. What should a solid state laser have? Is interlock and key switch all you need?

How do you implement the interlock? Should it simply cut all power to the laser or are there other ways?

By reading the Swedish regulations I get the impression that the beam path must be physically prevented from reaching areas that the audience have access to. I'll contact them about this, but do you have any nice ideas of how to implement something like this? Barn/sliding doors?

[MechEng3]

Nice cabinet....I am glad to see I am not the only one to use old tech for projector cases. A bit of time in planning and you should have a nice projector. I have become partial to lower power RGB units....they are better for me....smaller...cheaper... and easy to transport. My next one will be 100mw 532.....200mw 660nm ....and 80mw of 473. Should be about the size of your outfit there. That thing is a monster in the making.

[Snilton]

I actually read about the regulations today here:
http://www.stralsakerhetsmyndigheten...MFS2008-14.pdf

I didn't read all of it but I couldn't see anything about key switch or shutter, just a kill switch.
Also the beam has to be 3 meters from the floor.

You have to seek a permit every time and i think its 3300SEK

From the PDF:

3 §

Lasrar ska vid överlåtelse för att tas i bruk vara utformade, klassificerade
och märkta i enlighet med svensk standard SS EN 60825-1, utgåva

3, 2003 eller på annat sätt erbjuda en likvärdig säkerhet.

[300EVIL]

Some of the best stuff I've ever found was in the trash. Nice Score! Looks like a perfect fit!

[Laser Ben]

Some of the best stuff I've ever found was in the trash

That is SOOO true!

[tocket]

Finally brought the case home and had time to do the preliminary layout. Everything fits very easily in there and there should still be plenty enough room for safety features above the laser driver.

The case even has a perfect hole already cut for the DB25 ILDA connector, as the GPIB port has the same dimensions.

I think this will be a fun build.

BTW, I visited the laser physics department at my school to borrow a power meter. The laser stabilized at 0.98W after warm-up, which I suppose is ok. Having been to their lab I have to say I'd love to know where they throw their stuff away. They have some serious equipment there!

[logsquared]

nice clean layout. i think you should paint it purple. while we are on the subject of cases, i stumbled across this extrusion at a local shop. check this post: http://www.photonlexicon.com/forums/...ead.php?t=8885.

great for small projectors or large single color if the electronics can be made to fit.

[logsquared]

forgot to mention. check the inside of the hard drive. some older hard drives have nice aluminum diffraction gratings.

[sugeek]

forgot to mention. check the inside of the hard drive. some older hard drives have nice aluminum diffraction gratings.

Don't forget the VERY nice magnets (they have hurt me in the past)!

[tocket]

Did check the inside of the drive actually. Couldn't find any grating and the mechanism that moves the read/write arm is quite different from modern HDDs. It looks like a stepper motor is driving the arm. A thin sheet of metal is attached to both sides of the arm's base and wound one turn around the shaft of the motor. So no magnet either. The actual disks inside it were pretty impressive though. They're made of 2 mm aluminium and much larger than those from 3.5" drives. It takes nearly half a minute to spin them up and the disk makes a lot of noise.