Dichros PBS cubes etc?

[Dr Laser]

There are narrow band dicros. And combining 635+650 and 447+473 is simple. (PBS are used to combine 2 same wavelength lasers)The only problem narrow band dicros are not cheap. I would not recommend doing anything with 405. It's like me puting temporary 80mw blue into a 1.5W RG.... It's like adding a splash of orange juse into a pinte of vodka. Doesn't make any difference.

[tocket]

I think the answer to the mystery is hidden somewhere in the fact that color, in reality, is linear in the electromagnetic spectrum, but human perception of those wavelengths seems to be circular. That is to say, it seems to make sense that the rainbow has no ends. Violet blends right back into red. If you look at the chromaticity chart, there is a thing called "The Purple Line". This is the straight line that joins violet back to red to close the shape. What? Huh?

James.

Well, the purple line is just a virtual line; it isn't monochromatic like the rest of the border. Yet its colors can't be reproduced using anything except for a mix of red and violet. This is all very confusing indeed, but I'm fascinated by it.

Here is what I was talking about earlier.
http://en.wikipedia.org/wiki/Image:CIE1931_XYZCMF.png

If the color response looked like that a circular perception certainly wouldn't be farfetched. I'm not a fan of circles though. Perhaps a triangular perception. No, wait... I hate triangles.

This is the way to do it:
http://en.wikipedia.org/wiki/Image:S...m_locus_12.png

The surface is missing though.

If you want to make your head spin, imagine that curve for a tetrachromatic species. Tetrachromacy must be a very interesting experience.

[buffo]

For what it's worth, Semrock has an off-the-shelf dichro that will mix 405 nm with the rest of the spectrum. So if you really want to add near-UV to your projector, there is a way to do it without resorting to a PBS cube.

However, I imagine that the reflect 405 nm, pass everything else dichro will be just as expensive as the reflect 635nm, pass 660nm dichro. (Roughly $100 each for a lot of ten at 12.5 mm diameter, or around $165 each for a lot of ten at 25.4 mm diameter.)

Adam

[James Lehman]

I'm not a fan of circles though. Perhaps a triangular perception. No, wait... I hate triangles.

What did a circle or a triangle ever do to you ?

Since we're kind of on the off subject...

Do you have any ideas about converting RGB to RGBV ?

James.

[bridge]

Hello Mate,
First, I love your design, join the 405 blue ray is not bad choice,although it is much darkness than 473nm, I really love the violet light. .
ok, below is my view, wish that will be help for you
(1).you need at least one PBS for your projector, as 635 and 650nm is only 15nm between tehm, dichroic coating is not easy things, I am sure there is not standard dichroic to do that working, if anyone can do that, you will pay much, much more than one PBS cube.
(2).combine 405 and 473, yes need dichroic reflect 473 and pass 405, or the other way, maybe there is no standard products, but really can do it, problems is no standard products and you only need one, prices maybe some little high.
(3). the last mirror, reflect blue and pass green and red, you should have one thing in mind is there many people are used 473 or 457nm blue, so most dichroic are coating only reflect 473 and 457nm blue, not reflect 405nm, so you need to confirm with them, we don't want the dichroic you buyed lost most of your niceful 405nm lasers. we are waiting for see your RGBV projectors, pictures is always welcome here, .
Best regards!
Bridge

hi ppl.

ok cant wait soon to start building my projector but still need that blue one. ive found some nice sellers and prices.

Im the type who wants everything in my hand untill i start installing etc etc.

Anyway, im litle confused about the dichros and PBS cubes as i thought i would only need dichros.?

my projector will conisist of:

1 x green 532
2 x red 650 (or perahps one 650 and one 635)
1 x blue 405
1 x blue 473

Couldent i just do like this ?

[stanwax]

Violet in a projector - I say well done for thinking its worth trying - thinking outside the box to coin a phrase. Its amazing as I only mentioned this to Andy con in a PM yesterday. To those who are just saying its a waste of time I say lets just see shall we - unless you have tried it in an RGB with the sort of power he is talking about then you cant say dont do it. As for controlling the colour it will be simple tied in to the 473 so they modulate as one. Some systems can cope with an 'extra' blue indeed ilda has provision for it on thier connector definition (pins 8 & 21). This was obviously designed for 458 argon but could be used for 405. but for most DACs tying it into the other blue will be the way and it has to make a difference to the blue colour - it may not be significant but you never know.
So what Im saying is I think its worth the excercise and the experiment cos lets face it if we had never been adventurous we would still be peering out from the water thinking 'that land - we can't survive there its too dry so not worth bothering with'.
Go for it - I certainly will be trying it and though we both may fail or get rubbish results at least we will KNOW its not worth it, and maybe we will just see something beautiful.

Rob

[tocket]

What did a circle or a triangle ever do to you ?

Since we're kind of on the off subject...

Do you have any ideas about converting RGB to RGBV ?

James.

RGB to RGBV... that's tricky as you're expanding the gamut and adding completely new colors. I guess the sensible thing would be to let the V-channel help with the otherwise problematic purple line, as well as add a little punch to blue and white.

As for the function to do this, V=f(R,G,B)... that's maths beyond what I'm comfortable with. The reason I hate triangles (and circles) is trigonometry.

[Dr Laser]

Is someone got a 2+W 405nm then yes it'll be a good addition to a projector. 2W 405nm will be around 250mw 473nm and 250mw is very visible. But in this situation I very believe that that 405 will be out of HD DVD and in this case it will be very useless.

PS....Maybe I'm always thinking on big scale. If you're planing to build a small home projector then yes 405 will be a good addition. If you're plans to make a mid size show then it'll be useless below 2W.

[rfourt]

Thnx for all the answers.

yea i know the 405 is only 150mW without any filters and belive it will only produce about 70mW with it?

But if its working good with drlava´s driver board i will probably by some more 30$ each. and combine them. if possible there is. and mayby come up to atleast 2-300mW, oki they will hardly be visable when scanning and such with my 1.7Watt green and 8-1000Mw red. but for beamshows in a wery dark place. it can be nice.

i will test this anyway and see how it goes. might just turn out to be crup but as stanwax just said i atleast tryed. i have to try... the violetish color is amazing.

I will document this with alot of pictures, even thinking about starting a blog/tuturial page about it. with pics and videos etc etc.

but as i sayd im waiting for all the products and gears to be in my hand before i start to build anything.

ok. about the dichros or PBS cubes i think i get it now

Dichros are made for combining different wavelenghts and PBS for the same waves.?

So if i would go with this setup.

2x 650 (or perhaps 1 of them 635)
2x 473
1x 532

it would look something like this. (picture 1)

on the other hand isnt a PBS cube a beamsplitter? from what i have heard it is? or am i wrong. anyway- wouldent if im right now, this mean that if i shine a red laser in it there will be 2 beams.?

.............................. ^
.............................. |
............................. ##
LASER>------------->##--->
............................. ##

(lol sry for the bad pic but the ## are the PBS

Or does it matter from wich side i put the beams into the PBS,.

like this.


...............Mirror
Laser>----> ¤
................ |
Laser>---->##
................ |
................ |
................ |
................ v

[stanwax]

The PBS is a beamsplitter that will split one randomly polarised laser into 2 oppositley polarised beams. We reverse this and put in 2 polarised beams and combine them to make one beam - pretty neat!

Rob