Hi there I want to add a 405nm diode to my Laserworld 700RGB pro advanced.
I haven't modified nor built a laserbefore so I need some help.
This is what my laser looks like. I know it's tight.
The order is G -> B -> R -> Scanners
Where would you put the 405? What dichros should I use and where?
Check to see how much the blue dircho reflects the 405nm light. If it passes most of the 405nm, you could just add the 405nm diode at the beginning of the optical train. UV > G > B > R > Scanners. You will have to get a reflect-green dichro though (they're cheap)Quote:
Originally Posted by jestern
If the blue dichro reflects too much of the 405nm light, you could PBS (Polarizing Beam Splitter) the blue and 405nm diodes, thus combining them. Your whole optical train would have to change though. It would look like this... UV/Blue > G > R > Scanners. You would need to get a reflect-green dichro though. It's not as simple as dropping in a new diode but it also isn't too difficult.
EDIT: I can't tell if the green optic in your pics is a reflect-green dichro or a regular mirror. If it's dichro, you won't need to buy one for the green laser. If it's a regular silvered mirror, you will.
You can buy a pass rgb reflect v dichro. I think thor sells them. Based on what I see I think you could gut that and start over pretty easy. Is that just ttl?
Thanks absolom7691 that all makes perfect sense. I have 2 questions:
1- Can you expand a bit about the PBS. Should they be coated? Can you suggest which kind of specs maybe a model?
What does it involve in terms of geometry to mix the two Blue and UV beams? My space as you see is not huge how would you mix them?
2- In theory I could also try to find a dichro that reflects only between 420 and 500 for the blue part. Don't know if that exist...
Is it cheaper / easier than the PBS solution?
Thanks Kecked, yes that is what I was also thinking.
Then you would add the UV at the end of the chain: G > B > R > UV > scanners right?
how does that compare to the other solutions in terms of price? My laser is diode I can dim.
Thanks guys for the help!
Yes put it last in the chain to minimize losses. Yea I think you could redo that system and just use the case. Get the xwossie drivers upgrade the diode optics. Don’t forget to change the blue for violet with a switch or use an additional color line but many da s don’t feed the extra line.
Kecked is correct that your 405nm goes last. EdmondOptics has a “cheap” dichro that will allow you to combine it. A 5mm dichro is about US$150.
Quote:
Originally Posted by dkumpula
That's why I had recommended a PBS cube. Cheaper but a bit more complicated to set up.
If you do a cube make sure to put the 405 straight through the cube to minimize loss and use a power meter to peak the polarization so you get the maximum through the cube. You can not do that by eye at 405nm.
at that wavelength you are on the hairy edge of coatings and a purpose made cube will be a lot more expensive than a dichro.
Good point. As you also pointed out, its a wildcard on the existing dichros. Most (modern) dichros in my experience aren't geared towards the low end of the spectrum. I should do some measurements of the more commonly available ones from Goldenstar, Kvant, etc. The cube approach might be harder to work into the existing projector the way its laid out. (That build has some odd features, doesn't it?) Getting three beams through a tiny forth dichro and then properly aligning in the near-field when you can't easily see the 405nm beam hitting the front of the dichro is no picnic either.Quote:
Originally Posted by absolom7691
Surprisingly, the commonly available PBS blue cubes reflect 405nm better than they pass it. I did a series of tests a while back available here: https://www.photonlexicon.com/forums...e-Test-Results Dave's cube from LasershowParts is my favorite for 405nm and the blues.Quote:
Originally Posted by kecked
In regards to the rotation of the diodes, I agree that you can't easily judge the correct orientation of those by eye when watching power through the cube. That said, you CAN look at the diode itself. When you look in the can, you will see the little tiny heatsink that the diode elements are mounted to. If you have a good eye for horizontal and vertical, orienting that heatsink line horizontally will (generally?) give you the polarization necessary for going through the cube and rotating it 90 degrees so the heatsink looks like a 'vertical line' will give you the necessary polarization to reflect. This is my experience with every diode/cube combo I've encountered, but I'm sure there are exceptions.
Another way is to look at the notches on the back of the diode. The two notches that are across from one another are typically aligned in the same orientation as the heatsink in the diode. Again, if you have a good eye for horizontal and vertical, you can orient these by eye when putting the diode into the mount. Just be careful that it doesn't shift as you assemble it.
A final way to check is to look at the resultant beam once mounted and adjust the colimation lens so it is slightly 'under-focused'. This gives you a line that you can orient horizontally (for through) or vertically (for reflect). This last approach is probably the easiest if you don't have a power-meter and purchased the diodes from DTR in the round cylinder mounts.
Again, this reflects my personal experience and I'm sure there are exceptions where these approaches do not work as described.
Happy upgrading!
-David
Thanks everybody REALLY! I'm learning so much ... so from what I understand I can do this:
IF my Blue Dichro passes most 405 (but probably difficult) I can follow this chain:
UV
Mirror
G
Dichro Mirror that lets UV reflects G low pass < 500 BUY (if it's not a mirror and is a dichro green)
B
Dichro Mirror that lets G/UV reflects B notch 420<x x>500
R
Dichro Mirror that lets G/UV/B reflects R low pass < 600
Scanners
ELSE
G
Mirror
B
What I have now
R
What I have now
UV
Add something that passes RGB and reflects UV (any link here????)
Am I right?
I disregarded the PBS possibility as it seems difficult in my opinion to have space there to collide two diodes. I also would like in principle, but maybe I'm too optimistic to use RGB and UV simultaneously by using one channel of the ILDA to drive the UV driver. I forgot to mention that I use voltages directly into the ILDA cable, no software or computer. So that would be pretty easily as I have many ILDA channels free.
I have never changed/mounted a dichro (nor modified a laser) but I can find a friend that can guide me. My idea is to also use the fluorescent paint to focalize the beam onto the wall with the three RGB beams. Does that make sense or is it completely insane?
The screen material has a lot to do with what a 405nm diode spot will look like. Some paper has whitening agents in it and if you wash a white sheet in the right kind of detergent it will also. When you shine a 405nm laser on that it looks bright bluish white. You can't see the violet at all. If you are interested in using fluorescent pigments, you will probably find that the blue laser lights it up just as well as the violet.