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Thread: RGY Bandpass Filter....

  1. #1
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    Default RGY Bandpass Filter....

    I am looking to build an RGY laser head out of a 180mW @ 532nm DPSS and a 225mW @ 650nm laser diode. After looking at the Edmund Scientific catalog for a bandpass filter I'm even more confused... Too many choices. What type of filter would be best for my application? should I pass green and reflect red or vice versa? what type of filter would render me the lowest amount of power loss? Edmund Scientific is expensive! Does anyone have a filter they could sell me or know where I can get what I need for a decent price?
    Thanks!
    Adam

  2. #2
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    Welp, 1st - welcome to the forums!
    2nd- like everyone here says "this is a money-pit hobby" so get ready for a drained wallet. Gotta pay if you wanna play. I use the Edmunds pass green/reflect red dichro primarily because you want to pass the green thru more optics than the red & blue (least expensive route- the greens are cheaper per mW) and the reflectance % is better on that filter.
    There are people on this forum who routinely sell optics- just have to ask & look around a bunch. Check the buy/ sell/ trade threads.
    Cheers
    Steve

  3. #3
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    Quote Originally Posted by steve-o View Post
    Welp, 1st - welcome to the forums!
    2nd- like everyone here says "this is a money-pit hobby" so get ready for a drained wallet. Gotta pay if you wanna play.
    read this on another laser forum.

    a boatbuilder wins a million dollars and the local paper asks him what his plans are now that he has this windfall.
    he answers"i guess i'll just keep building boats till the money runs out."

    this guy seems to have something like surplus /grab bag stuff.
    http://www.mwklasers.com/index.htm

    this item has filters in it.
    http://www.mwklasers.com/topsu1.htm

    he does orders by phone but i had to email him to get a call back.

    MKenny1989@aol.com

  4. #4
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    I bought an argon tube from Mike (MWK) years ago. He helped me with some useful info.
    He used to have a lot of stuff, but seems like less now..
    He might just be in it now part-time or sumptin...

  5. #5
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    Default

    I have some high quality ones from coherent that reflect 532nM and pass almost everything above 600nM. You can buy it from me on eBay for a very reasonable price!

    http://cgi.ebay.com/ws/eBayISAPI.dll...8866&rd=1&rd=1
    CLICKY!!!

    Admin: In the immortal words of Captain Planet: YOU HAVE THE POWER
    Admin: (To quit being a bitch)

  6. #6
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    Smile

    Quote Originally Posted by 300EVIL View Post
    I am looking to build an RGY laser head out of a 180mW @ 532nm DPSS and a 225mW @ 650nm laser diode. should I pass green and reflect red or vice versa?
    Hi Adam, It's Adam!

    Generally speaking, dichro's reflect light with greater efficiency than they pass light. Also, you have lots of extra green. (Ideally your color mix should be 4.6:1 Red:Green.) So, if it were me, I'd choose a dichro that will reflect red and pass green. Expect to pay around $45 for it.

    Have a look here for some current prices from Edmunds. The 6th one down on the list is the one you want. (Though the 5th one will work too, it's only 5 bucks cheaper and it's HALF the size, so unless you like dealing with small optical components, I'd go for the larger one.)

    You should see better than 98 percent reflectance of your red from that one, and around 90 to 95 percent transmittance of the green. (It will also pass blue for that matter.) Pretty much anything shorter than around 590 nm is going to get through at at least 85%, and the transmittace efficiency will go up FAST beyond 590 nm. (Going the other way on the spectrum, at 615 nm the transmission is down to 50%, and at 640 nm it's at just 2%.)

    Adam

  7. #7
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    Quote Originally Posted by Buffo View Post
    Hi Adam, It's Adam!

    Generally speaking, dichro's reflect light with greater efficiency than they pass light. Also, you have lots of extra green. (Ideally your color mix should be 4.6:1 Red:Green.) So, if it were me, I'd choose a dichro that will reflect red and pass green. Expect to pay around $45 for it.

    Have a look here for some current prices from Edmunds. The 6th one down on the list is the one you want. (Though the 5th one will work too, it's only 5 bucks cheaper and it's HALF the size, so unless you like dealing with small optical components, I'd go for the larger one.)

    You should see better than 98 percent reflectance of your red from that one, and around 90 to 95 percent transmittance of the green. (It will also pass blue for that matter.) Pretty much anything shorter than around 590 nm is going to get through at at least 85%, and the transmittace efficiency will go up FAST beyond 590 nm. (Going the other way on the spectrum, at 615 nm the transmission is down to 50%, and at 640 nm it's at just 2%.)

    Adam
    Hey Adam,
    Thanks, that's the info I was looking for. A price of $45 is right for me. I am glad to hear it has very little loss too.
    Thanks for everyones comments!
    Adam

  8. #8
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    Quote Originally Posted by 300EVIL View Post
    I am looking to build an RGY laser head out of a 180mW @ 532nm DPSS and a 225mW @ 650nm laser diode. After looking at the Edmund Scientific catalog for a bandpass filter I'm even more confused... Too many choices. What type of filter would be best for my application? should I pass green and reflect red or vice versa? what type of filter would render me the lowest amount of power loss? Edmund Scientific is expensive! Does anyone have a filter they could sell me or know where I can get what I need for a decent price?
    Thanks!
    Adam
    which one is expensive reflect which one, because reflection is high than the transmission.
    I really had the dichro mirror that you want.only $40(FOB) one pieces,dia:15mm ,transmit the green and reflect the red.if more,it will be cheaper.

  9. #9
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    Lightbulb

    bridge... The Edmund's optic is one of the "best", and it is 25mm. I am not sure if your 15mm for $40 will compare well.
    Love, peace, and grease,

    allthat... aka: aaron@pangolin

  10. #10
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    Quote Originally Posted by allthatwhichis View Post
    bridge... The Edmund's optic is one of the "best", and it is 25mm. I am not sure if your 15mm for $40 will compare well.
    oh,no,Edmund's optics is only 12mm, $45.
    If you used one of my mirror, you will know which is better.

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