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Casio dichro figures

Benm

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Neither did i, until these casio diodes hit the market ;)
 





Morgan

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I already have a set in my mini-RGB setup and they work great. They do run backwards though. Blue first, then red, then green as opposed to most I've seen of Green first, then red, then blue but as pointed out... I have lots and lots... AND LOTS of blue so I can afford to waste the odd mW!

I got 2 sets from my purchase of a half set, if that makes sense! I.e. 1 quarter of a full dichro is enough for my needs.

@ EF - I guess the IR would make sense. I never thought to try the measurements with an IR filter. It may also be indicative of some instability from initial switch on, to final measurement. It doesn't vary too much but some. This would be the figure with the largest tolerances.

I'm glad it's been useful info.

M
:)
 
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I know this is old, but I cant figure out which dichro this thread is referring to, there are two from the projector a bigger one and a smaller one. which dichros reflect/pass which wavelengths and at what efficiency?
 
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Are you sure??
the ones I have seen are both ABOUT the same size... go look at the pics that TJ has for his sale of Mt projectors. and you can use your lasers to figure which one does what.

see Marks pics of the dichros here..

http://laserpointerforums.com/f39/fs-diodeless-projector-blow-out-65408.html#post939192

then blue colored one, I guess, is slightly smaller...

when you put a laser at 45 degrees you will always see two reflections but for the pass dichro the one spot is much dimmer than the other and reverse for the reflect dichro.
 
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damn its funny how weird my brain works. it never occured to me that the blue would pass both dichros. so for the life of me i could't figure out how to use them. so i will now use them in stead of my o likes. so thank you to the necro poster lol.

michael
 
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what I found wierd in the projector optic train is that the green(bounce back)reflects off the back of the first dichro while the blue passes thru front part of it ( the clear part of the green phosphur wheel ) here is a thread with many pics of the train with some of the lenses and all of the mirrors and dichros still in place.

I will look for some diagrams some one put up and add them to this thread.
You need to look at all three to see how each color is handled by the mirrors and dichros..
http://laserpointerforums.com/f49/14-projector-optics-place-63791.html
 

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Hi All,

I originally posted these figures in another thread but it's useful information should anyone be planning to build with these. My measurements are as accurate as I can make them but as they're the first ones I've taken from a set of dichros then there may be small errors as the setup is so small. Either way, the measurements can only come out low so if anything, expect better results from any future build.

Here is the data I got all at 45 degrees:

Blue, (445nm A-140) - 143mW raw: After 1st dichro 130mW, (91% pass): After 2nd dichro 120mW, (92% pass).

Red, (650nm LOC) - 248mW raw: After first dichro 240mW, (97% reflected): After 2nd dichro 237mW, (99% pass)

Green, (Duh!) - 120mW raw: After dichro 105mW, (87.5% reflected)

Therefore:

Pass blue, (91%)/reflect red, (97%)
Pass blue, (92%) and red, (99%)/reflect green, (87.5%)

I think these aren't half bad but what would I know, right?! :tinfoil:

Any glaring errors or more standard ways to present this data then please point them out as I don't like making the same mistakes twice. ;)

Thanks,

M
:)

Thank you.
 
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You probably didn't need to quote the entire OP and reply to a 3-month-old message (and to more than 1-year-old OP) just to say thanks.

A better way is to just click the "rep" button under the person's name and leave a comment.
 
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You probably didn't need to quote the entire OP and reply to a 3-month-old message (and to more than 1-year-old OP) just to say thanks.

A better way is to just click the "rep" button under the person's name and leave a comment.

Off with his head! Off with his head! :D
 
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This is a relatively old subject, but I did some tests on these dichros with a very well IR-filtered green laser and was getting:

#1 Pass red/blue, reflect green: 85mW/86mW = 98.8% (green reflect)
attachment.php


#2 Pass blue, reflect yellow (green/red): 82mw/84mW = 97.6% (green reflect)
attachment.php


(Light is directed from the top left.)

The difference in denominator is because I had to wait for the laser to stabilize. So these dichros are very good especially for the (now) more expensive colors.
 

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