Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

Buy Site Supporter Role (remove some ads) | LPF Donations

Links below open in new window

FrozenGate by Avery

How to connect 3 laser diodes in this combiner?

borgqueenx

borgqueenx

0
Joined
Jun 30, 2008
Messages
1,660
Points
48
Last edited:





You considered Dichros right?
Or is this planned to be a rather compact set up and a dichro would add too much area?
 
I thought of dichros but how could i mount them since there are no threaded mounting holes in the middle of this block?
Im wondering what the creator of this block had in mind. How he thought of combining the 3 diodes.
 
borgqueenx said:
I thought of dichros but how could i mount them since there are no threaded mounting holes in the middle of this block?
Click to expand...

You've been working with projectors long enough to know dichros don't combine lasers of the same color, sir. Two knife-edge mirror mounts go on that base. You need to drill your own holes.
 
Cyparagon said:
You've been working with projectors long enough to know dichros don't combine lasers of the same color, sir. Two knife-edge mirror mounts go on that base. You need to drill your own holes.
Click to expand...

thought it already involved drilling:(
And no i didnt know that. i thought it would be possible to have a dichro that lets through desame color on one side and reflects on the other side.
 
I believe that mount was designed for knife-edging 3 445's.
It looks like a mount that was posted on PL a while ago. I don't remember by who though.
 
If it was made for it, i dont get why it doesnt have threaded holes already in the middle:(
 
Dichros work based on wavelength, therefore same wavelength lasers will do the same thing when they hit the dichro. Not useful in this situation unless you use the dichros as mirrors instead of pass filters and knife-edge the three diodes. I imagine you'd only do this if you found dichros for way cheaper than mirrors.

PBS (Polarization beam splitter) optics work based on polarization, and that you can change by rotating a diode 90 degrees. However, PBS only able to combine two polarized beams into a beam with polarization in two orthogonal planes, so you can't use another cube to add a third beam because if you were to shine this combined beam into another cube, one part of teh beam would pass through and the other half would reflect, splitting the combined beam into two.

That looks to be meant for knife-edging, and I guess you would have to buy your own mounts and drill your own holes
 
borgqueenx said:
If it was made for it, i dont get why it doesnt have threaded holes already in the middle:(
Click to expand...

... Here, I'll walk you through this.

You said so yourself that this was for combining beams (and it is - I recall the device from PL). There is currently nothing in the middle to do the combining. Ergo, you must put something there to do the combining. The only way to combine three beams of the same colors is knife edging. This requires mirrors. Mirrors require mounts with which to adjust their angle. The mounds need to be held in place. The easiest way of holding the mounts in place is screwing it down. So do it. ;)
 
Someone else, a really cool guy also here will do it for me and i pay him for his time:)
I needed the info for he didnt know how it was designed:)

Thanks!:)
 
If you're willing to look hard enough, and bin your diodes, you CAN combine two multi-mode blues with a dichro.

It just requires that you bin out a very low wavelength diode and a very high wavelength diode, and then find a dichro with a very steep and perfectly positioned reflection/transmission slope.

On the cheap, this is the only candidate I've found:
Optical Filter Dichroic 460DRLP 26X36 Beamsplitter @45 | eBay
Even with that steep of a curve, you'd get some losses. But a 441nm and a 458nm (which are the lowest / highest I've found) should combine well enough that it would be worth the effort.

If your'e willing to pay a bit more, Edmunds has a slightly better option I think:
Dichroic Longpass Filters - Edmund Optics
"450nm Dichroic Longpass Filter, 12.5mm Diameter"
 
Last edited:
I think you're reading the X-axis wrong. It looks to me like you lose 70% of the 458. The ones from edmund look the same. Transmission is at 470. It's good for 445 and 473, but not so much for 445 and 458.
 
Cyparagon said:
I think you're reading the X-axis wrong. It looks to me like you lose 70% of the 458. The ones from edmund look the same. Transmission is at 470. It's good for 445 and 473, but not so much for 445 and 458.
Click to expand...

It's pretty hard to tell with that low-res graphic for the eBay one. I suspect the Edmund one is a lot better though. I wish the provided a curve.
 
You must log in or register to reply here.





Back
Top