First scanner build (eventual tutorial)

[paulzimm]

You want the beam to enter from the side, then hit the bottom "X" mirror, then bounce to the top "Y" mirror, then exit the front.

 

[chipdouglas]

sweet!!!!


michael

 

[chipdouglas]

where the hell is my usb sound card!!!!! i now feel like borgqueenx LoL. is borgQUEEN a boy or girl?


edit... my usb sound card just arrived. i no longer feel like borgqueen, i am no longer waiting. my question still stands about its sexuality.

 

[chipdouglas]

bump.... i finally have all my parts... so here is a mock up. if stuff looks out of place then help me damn it!!! jk about the damn it part. i really do value everybodies help. but i'm excited that it is finally coming together. so with out further adieu...

ps, i am making my own optics brackets. they will be L brackets with a tall rectangle hole with an inlay. this will give me the abilty for vertical adjustments.

 

[ElektroFreak]

It looks ok to me as a preliminary layout.. My own personal recommendation is that you bounce the combined white beam off of an adjustable mirror prior to the beam reaching the galvos. That way if anything ever affects the overall beam alignment into the galvos you have an easy way to adjust it back.

 

[chipdouglas]

ahh, i didn't know that and my next question was that, i think i read from you a while ago that i should do the same with my green too? i will be moving my modules/heatsinks a few inches inland so i can put my tec behind them:
should i use a tec at all
if yes, will condensation be an issue? i bought an extra flex mod for it.

also since i'm using 2 loc's, do i need a flex mod for each or can they share one?

 

[chipdouglas]

bump...

 

[ElektroFreak]

With the kind of usage involved in cooling a laser diode there should be no condensation using a TEC. You really only want it to keep the diode around 25C or just below it rather than ice cold.

With your LOCs you can run 2 off of the same driver.

 

[chipdouglas]

Cool great info.

i just realized i still need a pbs cube. hopefully i can get one from dave when i get my last LOC.

 

[Benm]

With the kind of usage involved in cooling a laser diode there should be no condensation using a TEC. You really only want it to keep the diode around 25C or just below it rather than ice cold.

Well, there are pro's in cooling the red diodes to freezing temperatures, as the wavelength will shift down a bit. Its only a few nanometers, but every single one counts as far as brightness is concerned. It will complicate your build though, and might not be worth the worries for condensation and ice formation.

 

[chipdouglas]

good point benm. so i think i should mount my tec as close to the reds as possible. are there products, pastes, gels cloths or anything that prevent condensation?

michael

 

[ElektroFreak]

You could construct a sealed enclosure and either fill it with inert gas, such as nitrogen, or place a small desiccant (silica gel) packet inside. Either way, if you're cooling below the dewpoint (which varies from day to day) you'll need an airtight enclosure.

 

[laser_freak]

ahh, i didn't know that and my next question was that, i think i read from you a while ago that i should do the same with my green too? i will be moving my modules/heatsinks a few inches inland so i can put my tec behind them:
should i use a tec at all
if yes, will condensation be an issue? i bought an extra flex mod for it.

also since i'm using 2 loc's, do i need a flex mod for each or can they share one?

They can share one flexmod, but if they are being run in series than they need to be electrically isolated from each other. You can run them in parallel so you don't need to electrically isolate them, but then you need a ballast resistor to balance the small electrical inconsistencies between the diodes.

Also, you probably don't need a TEC. If you do use a TEC, you need to have the cold side directly thermally connected to the diode mount, and the hotside connected to either the baseplate or a large heatsink + fan. You should NOT try to cool the whole baseplate with a TEC. It would be too much work for even a large TEC.

 

[jaycey]

Maybe I am not seeing the picture correctly but you need the scanner block close to the edge of the optic table otherwise your beams will be bouncing around the inside of the case.

 

[chipdouglas]

^^^^ good point. I did not know that. also that piece of aluminum is not my final size. i just haven't cut it down yet because i don't have a final layout yet. thank you.

michael

 

[hakzaw1]

This thread needs a sticky if it does not already have one-- many questions get answered here TY to one and all---hak