Sell: Trichros

[Spec]

Hey Guy: They are AR coated. Twist them under a light source to see the "fade" Had they not been the trichro would eat about 80% of the beam power.

Theres a lot of proverbial hoops for the beam to jump through Tons of glass there compared to standard lenses.

You should be measuring about 12% loss through the trichro. If your getting more "loss" start looking at the 532nM laser for 808 and 1064 bleedthrough. that stuff bounces right off the green input side

I have one 532nM laser that measures a little under 200mW through the trichro. turns out there was about 100mW being blown due to IR.

See ya around man!

[jayDC]

Well they may be AR coated, but I get some back relection off the lenses..

[Spec]

It was recently brought to my attention by Yaddatrace that might have something to do with the coatings being inverted on one side due to the orginal application of this device.

Quoting Yadda here; "My guess would be that they AR coated the glass front of the prism, and bonded the dicros on each window to the sides of the prism... that way they wouldn't need to AR coat the dichro portions."

These things came out of 3ccd imagers, the white light goes in the large apeture and breaks into three seperate color channels for the seperate ccd's

The reflection is worse at large angles, if positioned about 20 degrees off square you will find 3 bounced beams, confirming Yaddas qoute above.

Ive been playing with one here for the past 15 minutes. Ive managed to get the backreflection down to a single beam of 12mW with a 250mW source unit.

Still: If you are not happy with the unit I will be glad to refund everything including shipping. I dont want unhappy members of the board

[marconi]

Thats absolutely correct...
The coatings are reversed in our application

still...

Hard to beat for the price !!!

*^_^*

[jayDC]

I agree, and I'm sure it's not impossible to get the correct sides coated..

[yaddatrance]

Heh, about adding AR coatings to optics...

When we finished building that blue scanhead enclosure in my gallery, we
looked at getting a simple AR coating done on some glass for the window...
The shops we talked to all asked for $600 per pane!!!! Suffice to say, that's not
how we ended up going (Surplus!)

Now if any of you know of a good inexpensive place that does AR,
please do share!

[jayDC]

Well, I'm going to talk to a couple of eye-glass shops in my neighborhood. May be if they are interested in what I'm doing I can get them to coat the 3 little dichros pro-bono. If it works out for the better I'll let you know.

[yaddatrance]

One thought... AR coatings have power thresholds... I'm not sure how much
power the AR coating on glasses can sustain. My guess is... as long as
you stay in Class IIIb you'll be fine. I wouldn't run anything Class IV though
it since you run the real chance of the AR coating causing ablation of the
optics.

[jayDC]

Well, how do we know the actual glass will with-stand class IV lasers, they are made for some sort of photodetector array in a CCD camera..

[yaddatrance]

We don't, but most dichros take more than a watt and I'm just guessing, but the prism looks clear enough, the only thing I'd be worried about is plastic film AR coating which might melt and turn optically opaque...