Help picking Dichros...

Greetings,

I'm only a few pieces away from being able to build a RGB projector. I was looking for optics and found a seller, on eBay :D , that has several dichro optics for sale. I just don't know which I need. Could someone help me chose :?:

The seller has 7 optics the I thought would do the trick. I think I need what, 2 maybe 3 of them. I guess a good question is what color should you start with in a projector? Or does it matter? I need one mirror, broadband? to reflect the first color beam onto the "path", a dichro to reflect the second color and transmit the first making the first combined beam, then a second dichro to reflect the third color and transmit the first combined beam making the second combined beam that should goto the scanners... Correct?

First one Reflects at 615 to 800, Transmits 450 to 590... I'm not sure what random polarization means though... :?

Next Reflects at 500 to 530 and 580 to 780, Transmits 450 to 490

Third Reflects 575 to 700, Transmits 400 to 550

Fourth Reflects 400 to 600, Transmits 615 to >800

Fifth Reflects 525 to 700, Transmits 400 to 500

Sixth Reflects 510 to 590, Transmits 610 to 670

Seventh and last... Reflects 500 to 620, Transmits 650 to 800+

Would this be a good place to purchase dichros? I have been looking a little but this is the only place I have really found... :?

Thanks everyone :!: :!: :!:

The way I did mine was as follows:-

Set the blue laser up 1st pointing directly at the galvos, this way there is no loss on a mirror.
Then the green at a dichro, so you need a pass at 473 and reflect at 532, so use the fifth (pass 400-500 reflect 525-700),
Finally introduce the red with the third (pass 400-550, reflect 575-700).

Jim

Thanks man! I was doing some drawings and came to the conclusion that this configuration is the only way I can do it with the mirrors listed... I think... that was a few hours ago... :roll: Your's is better reasoning though... :D

Here is what I use for dichroic filters:


http://www.edmundoptics.com/onlineca...productID=2433


Also, I looked at only a couple of the links you listed, and there was no real spec on what AOI is required to obtain the transmission/reflection specified. If you follow the link above it will take you to what you really need. Notice they are specified for 45 degree AOI. There is also some good info to read on the Edmund website about dichroics.

David

Thanks David. To get approval I have to go with the lowest bidder... This is the prototype and I have to build it on the cheap or the girlfriend/boss won't allow fundage... :oops: :D I know I may regret it, but it won't get built if I get top of the line for the prototype... I wish I could. :(

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cheap or the girlfriend/boss won't allow fundage...

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Ha! That I understand! Except, I have to go through a wife and a daughter to get approval for my laser related expenditures!

David

We've been living together for almost 8 years... might as well call her the wife... :shock: :D :roll:

Seems like (almost) everybody here has the same problem with the wife or girlfriend (except marconi perhaps :D ).

Just try to explain thet the more expensive ones make "prettier" pictures :lol:

Jim

Quote:

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Originally Posted by DZurcher

Here is what I use for dichroic filters:


http://www.edmundoptics.com/onlineca...productID=2433


Also, I looked at only a couple of the links you listed, and there was no real spec on what AOI is required to obtain the transmission/reflection specified. If you follow the link above it will take you to what you really need. Notice they are specified for 45 degree AOI. There is also some good info to read on the Edmund website about dichroics.

David

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We stand by these as well, very low loss from these :D

Just remember, with low powered lasers, you really have to use the best optics, otherwise you waste too much power :(