Hacking a cheap laser module to get a divergent beam

[masterpj]

... I have all sorts of fibers (plastic and glass, from 0.03 to 2mm core diameter) in my scrapery and can give you pieces for the shipping costs ... some lenses too ...

Plastic fibers can be bought for some ten cents per meter ...

Viktor

I'm interested!
Allthough I believe most of the cost is focusing back on the fibers to get a proper beam out right?
*input and Output coupler

[VDX]

... I'll try to make some images of a diode, some pieces of fibers with different diameters (and cleaved ends) and a lens, to get the feeling for the 'simplest beam setup'.

Here some images of a test with a 0.1mm-fiber and the resulting output without lens and with a single collimating/focussing lens in roughly 1m distance, I've done some time ago ...






Viktor

[masterpj]

This is quite nice. It would be an interesting alternative to a pinhole as you could just shoot a beam over a short fiber and also gives the ability to re-orientate modules in any way you'd like in a projector without having to use bounce mirrors. Trade off is some power at the cost of a pretty nice round beam.

[VDX]

... here a "short'n dirty" setup made with a 445nm-laserdiode without collimator, a 280mm long piece of a 1mm glass-fiber (with coarse broken ends, not polished) and a random found lens.

- the three parts:


- far-field of the diode without lens:


- fiber attached to the output-window of the laserdiode:


- output only with fiber:


- lens in 50mm distance to the fiber end:


- lens in 20mm distance:


- lens in 5mm distance (collimated beam):


- lens in 1mm distance:



... with polished ends the emitted shape would be a perfect circle ...

Viktor

[kecked]

forget the laser and use a lightbulb or bright led. Then focus that. IE a mini pinspot

http://www.amazon.com/Chauvet-LED-Pi.../dp/B003N7BCFE