RGB beam splitter

Some people yesterday were asking about RGB beam splitters, so I thought today I would try and get mines out of its holder.

Got a few pictures of it removed from the holder, and if anyone doesn't believe that it splits RGB I'll get pictures to prove that as soon as my phones done charging ( Need to use the phones flash as a light source )

here are a couple Of pictures for now .

Oh and one last thing, these can be found in digital projectors, mines was from an old huge old Philps.

Image 1

Image 2

I'm not going to post the full pictures as they are too big, and I can't be bothered to resize them

-Adam

i remember hurcussciences (sp?) selling one of these RGB cubes, I really wanted it but the price went a good bit above $100

That much :-? I is going to make me some cash

You can actually put this at different angles from the light source and it causes the colors to combine so you get some really pretty colors

-Adam

Any chance you can get these out of cheap old electronics (like a projector, as you said)? Never thought they would be so expensive :O

you can get them from digital projectors, it should be behind the lens ASSY where the image is projected from, if I were you I'd try a newer projector, the one I used was a huge old Philips, nightmare to take apart. It will also have 3 diffraction gratings bolted onto it. and several dichroic mirrors/filters. and A LOT of lenses.

-Adam

yes, those are really great!
they are huge, cubic 3cm! all surfaces AR coated as well. i have one lose one from ebay, and played around with an old beamer/projector as well.
inside any 3xlcd projector you will find such a cube (perhaps a lil smaller, though), and as diachi said, much more. regular dichroic mirrors to combine all colors and mirrors and lenses. any lcd-projector with 800x600 resolution or better has three lcds, older/worse ones perhaps too. theres a page with all (!) beamers data, they write if its LCD and if its a single-lcd or three.
if its not lcd at all, it has a rotating color-wheel. these are dichroic too, and quite good as dichroic beam-combiners too.

now to the cube:
i shined my lasers through it some days ago, after having it around for long time already. red and blu-ray(!) go through without visible loss at all! green loses less than one percent which goes through the cube, instead of being reflected.
if someone needs to know i can measure the laserpower before and after the cube.

bonus: its not polarising at all. you can combine two lasers (like two red diodes for the red laser and so on) with a polarising cube and combine the now unpolarised beams with the cube!
means you can get three tiny polarising cubes out of drives (5mm cube in the ps3 kes-300a sled for example), combine two reds, two bluray, two greens, and combine everything with a dichroic-tricolor-cube. without much loss, and really inexpensive! calculate the costs for this, unbeatable! and, amazingly for an inexpensive 1 watts + (!) beam of "white", its all in a tight beam the diameter of a regular single-diode-pointer-beam, all 6 input-"beams" are on one dot!
(the other way is to use mirrors to place beams very close to each other. which makes the beam fat and ugly ^^)

so.. get a broken beamer from ebay or somewhere else. no matter how old or broken, you will find great stuff inside!
(except really old tube-beamer, which are as heavy as you are, and have three colored openings at their front)

manuel

Krutz said:

now to the cube:
i shined my lasers through it some days ago, after having it around for long time already. red and blu-ray(!) go through without visible loss at all! green loses less than one percent which goes through the cube, instead of being reflected.
if someone needs to know i can measure the laserpower before and after the cube.


manuel

Click to expand...

Thats how I hoped it would work, I knew the green goes right through, must be a standard configuration , wasnt sure how it would act with other colours , not having other colours to test it with. I think i'll keep mines then and it can eventually go into a scanner

-Adam

wow that's cool

i install projector's all the time at work i see like 3or 4 a year die. i just took one apart and guess what i found ? RGB cube as i get more i'll toss them up for trade . this one had 2 very small chips on the top edge (it fell from the ceiling ) ive bin messing with it look's cool . trade's anyone ?

The obvious disadvantage is they are very difficult to align.

Cyparagon said:

The obvious disadvantage is they are very difficult to align.

Click to expand...

I agree with that, before I traded my cube out to Dave I had a go aligning with a red and green and it was pretty tough to get a good alignment. It's good when you do get one though, saves so much space rather than using dichros and mirrors.

-Adam

Word of warning, don't go buying any old broken projector as they do not all contain a cube, I took an "infocus" apart and it did not have one, fortunately it was a broken one from work and cost me nothing.

@ DTMF, you could do us a favour and start listing ones you know to have a cube in

Regards rog8811

will do . i know the boxlight's have them . i'll look for the model #

Philips have them too, I don't know the model number though, it was a big old thing , huge in size.

-Adam

Guys - easy way to check if projectors have cubes or not

Just google the model number, a site like www.projectorcentral.com or www.aboutprojectors.com will come up

they say right at the top of the page "3 LCD projector" if they have a cube.

Nice find MM, thanks.....our oldest projector has a cube....all I have to do now is wait for it to die....

Regards rog8811