Hi Dimitris and wellcome aboard. Thanks for the pictures!
Originally Posted by
ddimitris
1. PBS is to combine 2 beams of different polarisation in one. Does this means to rotate the one diode 90* ?
This generally means that one diode has to be rotated 90 degrees (but this generates a + pattern of beams, which is not desirable. The use of a waveplate is recommended, this is a little glass thingy that changes polarisation by rotating it without the need to rotate the beam i.e. http://shop.stanwaxlaser.co.uk/wavep...risms-45-c.asp or the group buy stuff that dave at lasershowparts.com has available
Originally Posted by
ddimitris
2. Can i put 4-5 same diodes (ex. 445nm/1.6W Osram) and PBS in a serial way to combine all in a single beam and how many ?
well, how many you can combine depends on the size of your scanner mirrors. You can combine 4 fairly easily and fit on 5mm scanner mirrors, or you can do 16 like more experienced people here. Or, you can use the 9mm 445 diodes that can do 3watts each and get the job done with one or two diodes.
Originally Posted by
ddimitris
3. Can the last PBS or the dichros handle the increased power without cooling ?
yes they can. read through this thread, it has various good bits at various pages http://www.photonlexicon.com/forums/...ight=waveplate
Originally Posted by
ddimitris
4. The beam correction with anamorphic prisms must be made for every beam before every PBS or for the final combined beam ?
This is a bit unclear to me. How many PBS do you expect to use? Hate to spoil the fun, but you can only use one. If you add another it will just cancel half of your beams out (polarisation issues). So, assuming you use one pbs, you can place the anamorphic prism pair after the pbs. It also depends on how you stack the beams, so again, this question is a bit vague.
Originally Posted by
ddimitris
5. Same type diodes can be connected in series in one driver or every diode must have its own driver ?
you can connect diodes in series, or by using approrpriate resistors you can connect them in parallel. Ohm's law aplies. Most people prefer to keep things seperate and have a driver for each diode. This makes things safer for the diodes, as you risk loosing all diodes if you have one go open circuit in a multiple configuration
Originally Posted by
ddimitris
6. For better beam visibility at large distances (ex. 1-5Km) what is better higher power or thinner low divergence beams ?
I would say low divergence beams, but what would you be doing at that distance anyway? Check this out, too http://www.photonlexicon.com/forums/...ight=waveplate
Originally Posted by
ddimitris
7. I've seen PBS for 635nm and 445nm diodes. Can i use PBS for 520nm diodes and what type ?
any PBS would work. the 635 or 445 etc refer mainly to the antireflective coatings to minimise loses. so you can use a 445 pbs with 635 diodes, but the losses will be higher (i.e. closer to 10% instead of 2%). There are also broadband coated PBS that work with 400 - 700nm beams. Again dave will still have some of the broadband (BBAR PBS) left
don't think i have answered your questions, this is just a small intro to get the discussion going
Your post will receive more suitable answers if you provide more details, or even a quick and dirty sketch up of what you plan to build.
A 10 w rgb is no small deal, building it and keeping it aligned will not be too easy
In any case it is nice to see a fellow greek here, up to now it is you, me, a guy in chalkida and then the nearest neighbours are in malta and italy. makes it kind of difficult to arrange a laser meet
Last edited by LaNeK779; 04-11-2014 at 15:52.
"its called character briggs..."