Mitsubishi ML520G71...Red Holy Grail or Flashlight Fail ??

[DTR]

Not sure if these are what you are looking for.
http://www.surplusshed.com/pages/item/pm1081.html

But they are the ones Cyparagon was using over @ LPF in this thread.
http://laserpointerforums.com/f42/co...des-67410.html

[CDBEAM]

The cylinderical lenses really work well...with 3.3% transmission loss...See post #50 and #75. Why mess with prisms ? If you concern is with adjusting and securing DrLava optics....see attached drawing.

OK Steve...the 500mW's are in...200 bucks a pop....more than I had hoped for....BUT...let's see what DTR sells' em for ?? I would sure rather go that way !!


CDBEAM

[logsquared]

Update:

Turns out my thorlabs collimator had a defect in the lens. Looks like a bubble of flat spot right in the crown. Got a new one today and retested some things. Before I had an output of ~380mW at .5A with the replacement I have 440mW and the spot is a lot cleaner. The defect also made the beam seem taller. Now I measure ~3.5mm (3.1mm FL lens) where before it was 4-4.5mm. This seems to jive more with Solarfire's measurements. After correction to 1.8mRad the aperture is ~3.5mm X 4.5mm. If you "cut down" the 3.5mm axis to 3mm only 10% power is lost. After the telescope I put put a 3mm pinhole. The power before pinhole = 365mw power after = 240mw.

[Xytrell]

The cylinderical lenses really work well...Why mess with prisms ?

The prism I tested was $4. I can't seem to find a pair of Dr. Lava's cylinder lenses for sale, but I presume they're almost as much as the laser diode itself. Another advantage is that prisms have variable magnification.

I was able to get 3mm (on the fast axis) with divergence down to 1.17mRad. Sure you lose 30%, but for $4... you can't complain too much. power isn't everything. It's up to the end user.
Would you rather pay $50 for 300mW, or $200 for 400mW? (hypothetical values)

They each have their merits.

[andyf97]

The cylinderical lenses really work well...with 3.3% transmission loss...See post #50 and #75. Why mess with prisms ? If you concern is with adjusting and securing DrLava optics....see attached drawing.

OK Steve...the 500mW's are in...200 bucks a pop....more than I had hoped for....BUT...let's see what DTR sells' em for ?? I would sure rather go that way !!


CDBEAM

Got a datasheet for these 500mW?

[steve-o]

Got a datasheet for these 500mW?

Olike put the datasheet up on their site. just scroll down a bit

http://www.o-like.com/index.php?main...j2nr7po8di1dq2

didn't notice this before, they appear to be open can .. hmmm ..

[Solarfire]

The prism I tested was $4. I can't seem to find a pair of Dr. Lava's cylinder lenses for sale, but I presume they're almost as much as the laser diode itself. Another advantage is that prisms have variable magnification.

I was able to get 3mm (on the fast axis) with divergence down to 1.17mRad. Sure you lose 30%, but for $4... you can't complain too much. power isn't everything. It's up to the end user.
Would you rather pay $50 for 300mW, or $200 for 400mW? (hypothetical values)

They each have their merits.

Where did you get these numbers from? If you’re using prisms for 4$ and you’re getting 1.17mrad then you are also probably using a long fl collimator. Have you actually done any power measurement to backup your claim of only losing 30%? I got that during testing with a long fl lens (really good lens) and good AR coated prisms and that left me with a divergence of 1.8mrad and > 30% loss. So I seriously doubt that you are getting what you claim. The magnification of prisms is limited to a max usable magnification of 2.5 – 4 (depending on the materials) anything beyond that is useless thus the use of cylinder lens which don’t have this limit, provided one orders the correct magnification.

The lava lens costs 40$. How do you get away with 50$ when the diode alone costs 70$?

[andyf97]

The open can will likely be what makes the difference in power. Cooling ability and all that.

Olike put the datasheet up on their site. just scroll down a bit

http://www.o-like.com/index.php?main...j2nr7po8di1dq2

didn't notice this before, they appear to be open can .. hmmm ..

[drlava]

Glad to see people are testing these again..

The correct lenses are availabhle here:

http://hacylon.case.edu/ebay/laser_diode/Lenses.php

If desired, I can have a new run with slightly different properties optimized for red if the interest is there.

My test results were published last year, looked very promising if a 5-6mm fl collimator is used with the correction lenses.

http://www.photonlexicon.com/forums/...ode-properties

[andyf97]

635nm, its a bit orange but if usable will make a great ability to join with 650nm LOCS