I sent off for a quote recently and thought some of you might be interested...
"We provide single longitudinal mode red, green and blue lasers. The coherence length is >5 meters.
All CW red laser listed in our web, the maximum available power or a little less power is same price. all red laser including power supply.
single longitudinal mode and TEMoo mode laser $2950
Standard TEMoo mode laser $2550
638 nm, 25 mW; 658 nm, 50 mW; 690 nm, 30 mW; 785 nm, 80 mW
The price for the red laser are $2950 each including power supply. Delivery is 2 weeks after received the order.
The single longitudinal mode laser is no mode-hopping.
It is external cavity semiconductor laser.
The green single longitudinal mode laser provide >100 meter coherence length, we made them up to 150 mW.
Great profit margin on the external cavity laser. I'd be a little leery of the <100mt coherence length spec on the green laser and would ask for temporal data ( <100mt for how long?? 1hr, 24 hrs, 5 microseconds?)
I own a DPSS-laser from Crystalaser (100 mW, single longitudinal mode).
It is current and temperature stabilized (such like the diode lasers of AnalogTechnologies).
It remains very stable, (coherence length >100m for days)
... However I would non encourage anyone to buy such a laser for display holography.
Although they sell their laser as single mode, THEIR LASER ARE NOT SINGLE MODE.
Here 's what they answered, when I told them that I have problems with a second mode (contour-banded hologram):
"The green laser always come with 3% to 5% in side mode.
this is difficult to eliminate completely.
....
How strong the the second mode? if it is about 5%, it is difficult to remove.
you may reduce the power to see if it will be weaker or not?"
I reduced the power, but the problem remains the same.
Sounds like they cut a corner or two on optimizing the coatings. Easy to do if it's out of house ( you're paying for it ) and you're in a hurry to market.
Previously, I was taking a close look at those lasers, even though the costs were quite high. But I had no real doubts about their usefulness for holography (!)
It would seem that no DPSS laser is beyond question. Recently, I have been looking for a second-hand Coherent 315M. Does anyone have experience with that laser?
They can be great lasers to work with..But, due to the entertainment business, there's a bigger market for bright shiny lights than for stable holography capable systems. If I was going to drop a grand ( or more ) on a laser, it had better have great specs for holography and mean them..