Homemade High Power Diode Laser

Colin Kaminski · Post by **Colin Kaminski** » Fri Jan 23, 2009 3:01 am

I just got the Jameco catalog and they have a wide selection of multi-turn pots. They are quite common. you should be able to get one locally. (Or at least in the nearest big city.)

koliaco · Post by **koliaco** » Fri Jan 23, 2009 3:04 pm

Colin Kaminski wrote:I just got the Jameco catalog and they have a wide selection of multi-turn pots. They are quite common. you should be able to get one locally. (Or at least in the nearest big city.)

I found some trim pots locally, but here in New Zealand they don't have any electronic suppliers of Digikey size, and base on my search, to get all the parts to make the laser driver I will have to get them from many suppliers, So will stick with Digikey, just learned how to search on digikey and found trimpots sold as singles. Thanks a lot for your suggestions though.

Just another question, how many turn should I get for multi turn pot? 5 or 25? is it better to get more turns or less? as in schematic it mentioned about precision, i guess that would be higher number of turn?

koliaco · Post by **koliaco** » Fri Jan 23, 2009 3:18 pm

What should be specs for 22uF and 1uF capacitors?

Rated voltage?

Resistance?

Cheers

Solarenemy · Post by **Solarenemy** » Fri Jan 23, 2009 7:29 pm

koliaco wrote:What should be specs for 22uF and 1uF capacitors?

Rated voltage?

Resistance?

Cheers

For your use in this circuit the capacitors don't have a resistance and you rarely need to worry about what it is. In this circuit they are used to stabilize the input and output voltage of the power supply. Both of which in this case are 6 volts. For filter caps used this way you typically want about 10 to 15% headroom to account for spikes and such. So in this case a voltage rating of anything higher then 10 volts would be fine. The voltage rating on a cap should always be higher then the max voltage the circuit is handling but NEVER lower when they are used the way this circuit is using them..

Colin Kaminski · Post by **Colin Kaminski** » Fri Jan 23, 2009 8:37 pm

koliaco wrote:Just another question, how many turn should I get for multi turn pot? 5 or 25? is it better to get more turns or less? as in schematic it mentioned about precision, i guess that would be higher number of turn?

I like 25 turn pots myself. They take longer to turn through the range but you have more control. Both would work.

walschuler · Post by **walschuler** » Fri Jan 23, 2009 10:18 pm

Going back to an earlier point, given your time constraints and weight worries, I suggest you use commercial film. Slavich PFG-01 is essentIally the same quality as the plates, and less than half the cost. It is available 2.5in square, 4x5, 8x10, larger and also, I believe, in rolls. Who sells it near you (in Australia?) I don't know.

If Jeff Blyth's emulsion works you will likely get brighter images- it is dichromate- but I and my students get fine images on the PFG-01, and as Colin says, hand coating film is no joke. Even glass is not that easy.

By the way, how are you planning to illuminate the images??

koliaco · Post by **koliaco** » Fri Jan 23, 2009 11:02 pm

walschuler wrote:Going back to an earlier point, given your time constraints and weight worries, I suggest you use commercial film. Slavich PFG-01

Ya, I do think that would be my plan B as well, in case things do not turn up in time.

walschuler wrote:Who sells it near you (in Australia?) I don't know.

Yes I think there is distributor in Australia, but not NZ. will have to contact them to figure out. But otherwise will have to stick with Integraf.

walschuler wrote:as Colin says, hand coating film is no joke. Even glass is not that easy.

.
I had a plan to build film holder just for coating and maybe spining as well. Would that work? and if it doesnt then I will try Acrylic sheets 2mm thick, that would reduce lots of weight.

walschuler wrote:how are you planning to illuminate the images??

It will be illuminated with stage light, I am actually making a garment with a person wearing it and performing on stage.

koliaco · Post by **koliaco** » Fri Jan 23, 2009 11:06 pm

Colin Kaminski wrote:I like 25 turn pots myself.

koliaco wrote:So in this case a voltage rating of anything higher then 10 volts would be fine.

Thanks for your suggestions!

walschuler · Post by **walschuler** » Fri Jan 23, 2009 11:10 pm

If these images are to be worn and you are on stage moving with them, keep in mind their narrow field of view to the audience and that the images probably should be relatively simple, since they will be viewed from a distance. Try some samples for viewing and illumination issues ASAP, maybe using some holos you already own...

koliaco · Post by **koliaco** » Sat Jan 24, 2009 7:59 am

walschuler wrote:If these images are to be worn and you are on stage moving with them

Hi, I will not be wearing it, its for models to perform. the garment will be constructed as to be seen in total 3d form. My idea is to transform the look of the garment as the model moves - using multiple exposures to make rainbow copies to achieve reasonable brightness. I will need to be visible from distance of 40 meters and create quite good impact. About the image itself can be something very simple as you mentioned, cause too detailed wont be visible from a far anyway. Hope my plan will work out just in time!!! thats y I was so worried about brightness, sharpness is not a major concern. Stage lights are normally of high power, and since they are located at different distances, people who are in charge of choreography will have to plan it out so that my garment will appear first in the darkness (hope so:D)