JDS Uniphase 20mW 532nm Green DPSS Laser System - NT-LS-DG20-A

The NT-LS-DG20-A is a DPSS (diode pumped solid state) laser system with a rated maximum output power of 20mW and a wavelength of 532nm (green). The model identifiers don't make much sense for this unit and yield little to no search results, so it was given a custom ID like other laser systems. The JDSU model of the controller is 10075248 and the JDSU model of the laser head is 21006947-002. This unit was purchased used on eBay and is working. However, testing and measurement of the output power indicates that it is not operating at full specification. Laser output has been measured to be somewhere between 5mW and 12mW, therefore it is likely a low-power unit, but the beam is still quite bright. The laser head is connected to the controller by a DE-15 cable. Within the laser head is the pump diode, output power monitoring circuit, and multiple thermoelectric coolers. The controller is responsible for managing the current of the pump diode, regulating the temperature, and monitoring the output power.

Laser head connected to controller

The controller is less impressive than that of other units such as the Coherent CUBE. It accepts a 5V DC input at a massive 10 amps! I say it is less impressive though because of the very limited control and monitoring. The RJ-45 connector only offers the following monitoring signals: output power, power ok, laser ok, fault, diode current, noise level. Even worse, the only input signals are: laser on/off and TEC on/off. You cannot even control the output power of the laser. It seems like this is a "lite" controller as other JDS Uniphase laser systems have RS-232 control. Perhaps this is a budget laser system...

Controller connections

The warranty void sticker is present on the controller side as well as the laser head. But JDS is off the hook for this one, I don't think they are being jerks in this case. Since the controller is a seperate module from the laser head, the pump diode connections are passed over the DE-15 cable. Therefore, if the cable were to be disconnected on either end, the pump diode connections would be open, exposing them to potential static electricity. As the pump diode is extremely sensitive, a small discharge could destroy it. I am pretty sure the label is just to discourage disconnecting the cable and ruining the laser head. The laser head and controller are even shipped new with the DE-15 cable connecting the two.

Laser head side view

The external optic is a convex lens used to condense some stray beams along with the main beam into one. For some reason, this series of laser head lacks the internal optics to condense all the smaller beams into one with the main beam. Again, perhaps this is the budget version...

Laser dot on a piece of paper

Output power was measured at somewhere between 5mW and 12mW but the beam is still extremely bright. Documentation is extremely lacking for this laser system and seemingly most JDS Uniphase products. This may partly be due to the fact they went out of business (big surprise...) in 2015. But looking at the Internet Archive and other sources indicate they did not publish much documentation in the first place. They are pretty much the opposite of our friends Coherent, who are still in business by the way!

Green laser beam

While JDS Uniphase does have the pinout in the manual for this laser system, they couldn't be bothered to make the manual easily accessible (even when they were in business), therefore I have made it available below. A link to the manual can be found at the bottom of the page. Once again, our friend Sam who runs Sam's Laser FAQ has us covered!

JDS Uniphase controller pinout
5 INPUT LASER ON ENABLE (ground to enable)
6 INPUT TEC ON ENABLE (TTL high to disable TEC)

and yes, if you haven't guessed by now, I am not a fan of JDS Uniphase, but their lasers are cool :P