Never had to measure anything that high, but
probably would bounce off a piece of glass and
white plastic vernier caliper
Thats pretty much what i was doing. The problem is you get the dual beam reflection that way. Thats the problem i was having as using glass is basicly the same thing i was doing. Passing the blue and messuring the reflection but there is a 2nd reflection that makes it harder to messure.
Using a HR for Blue Mirror rather then a Pass Blue mirror what Planters said is a better idea which i like better. Which in turn wont give you that 2nd reflection beam becauseyour messuring the pass beam.
NICE.:bday:
I think your measurement technique is good. I use a HR broad band mirror I obtained from OSLS that reflects about 98% 0f the 445 @ 90 degrees and send that to the dump. I measure the 2% beam against a common black oxide finish that you find on a lot of machining blocks and risers etc. This is less reflective than standard black anodized aluminum.
Is the 1.85mm the slow dimension that ends up at 65 mm in the far field?
In any case this is fantastic. A 6 diode module might have a 6mm x 3mm beam and put a very conservative 24W downfield in a 3mm x 10mm (based on my expansion results with the nubm44). This is a 470nm beam as well. This would also fit onto a conventional projector scanner mirror.
Sweet.! Going to try it your way. Way better then what i was doing as there wont be that 2nd beam reflection.
Yes the 1.85mm is of the 65mm Far Field size.
I'd say its Near 470nm because it really all depends on the current and Temp one runs it at. It really matters on these just like the 462nm diodes. They have a much larger swing then 450nm diode that typically are only a few nm or so.
I just dont want to miss lead anyone. I dont know the temps and Current everyone plains on running these at so expect 465nm-470nm at ~4A bassed on the temp one plains on running it at.
Having said that....
Iam thinking if we run these around 4A it will probably fall around 468nm at ~25C. Though i dont think many plain on TEC cooling to regulate these diodes at 25C since the heat added from the TEC to cool say even 2 of these diodes Cubed @ 25 will be crazy without say water cooling the TEC's or something. So more then likely everyone will use a larger heatsink or copper mount to mount the diode in then to the module base or to the actual base plate of the projector.(Which may not even be enough) in a projector with no TEC's we will probably be at temps around ~40C-50C at best after running for about 30 min - 1 hour or so unless someone is using a very very large mount and large projector.. So then yeah i guess your right as ill say we will be at 470nm too at those temps.:beer:
The mount you see i used in my pictures Even that size mount mounted to my table will reach 40-50C in about 30 minutes being on straight. SO copper will be the way to go but even still we may need to add TEC's to keep it around 40C. Especially on a 6X module. WOW Thinking about it. TEC's or water cooling will be a must to keep it small.
I can see it now TEC's wont be the way to go on more then 2x or even 4x modules. More then likely a CPU style radiator or 2 with a custom water block mount that the diodes are in or that the diode modules mount too will be needed That should hold the diodes at around 40C on its own. Hmmm thats got me thinking now. We may be able to find a nice balance.
This is all very exciting because we have yet to really get into using these new High power diodes. Not many have used them yet in builds. So we have some new stuff to deal with and work out thats for sure with cooling.
Iam pretty sure we can use a CPU water block for a dual diode cubed setup just fine if one cannot go custom. But for more then that a custom water block will be needed.
We need some more diode testing an i have some more on the way to get some more WL measurements to see where typically these fall around but looking at the datasheet id say that my diode falls as a typical diode in the WL and power range. Iam sure there is probably going to be some Higher Binned ones that do higher in WL but i think this diode i tested is the typical WL we will see.
As for the cooling side of things. I need a Mill. Going to look into making some custom modules or water cooling plates.
I usually shine the laser on a LPM and move a pair of calipers in the beam. I start adjusting the calipers down until I see a 3-5% reduction on the meter. I do this in both axis. I used acid to blacken a pair of calipers at the tips just for this purpose. Usually the beam measures a lot less that it appears to the eye. Also, I should mention, the SA seem to increase in width in a linear fashion with current. So, the measurements should be taken at the full current.
Yes thats why i took it at 3.5A.
Pretty close to full power which should be at 4A or so. I noticed with Red diodes this is much greater then with blues. But your right. Should always be taken at full current.
Do you have your calipers rigged up to a stage.? My table is at a normal table level so trying to get my hand steady for that will be very hard. I could though hook it up to an X/Y, stage for increase accuracy.
