LaserWave Driver

[gottaluvlasers]

Anyone with a LaserWave Laser and driver *not* installed in a projector and an FB3 (preferably with Quick Show), PM me asap. doesnt matter what wavelength or what power.

Or if it is installed in a projector and it is easy to get to, let me know.

I would like to investigate something.

Thanks!

-Marc

[Synce]

PM Sent.

I have a laserwave and fb3.

[gottaluvlasers]

Thanks

anyone with an o-scope also??

[Things]

Whats the test?

I have a FB3 and a laser-wave driver, though it's a bit harder to access.

No scope though sorry

[buffo]

Apparently Marc is investigating previous complaints that the LaserWave drivers have a relatively low input impedance on the modulation circuit. (On the order of 1K ohms.) This is a problem, because you have a 100 ohm resistor in series with the output of the controller. So if your input impedance isn't really high (at least 10K or better), then you won't get a full 5 volts to your driver (more like 4.5 volts with the above impedance values), and thus you won't get full power out of the laser.

This is why the modulation inputs are supposed to be high impedance. (I believe this is even stated in the ILDA projector spec, but I'm not positive.) Evidently this was missed during the design of the LaserWave driver... It's not difficult to fix though. A quick and dirty solution would be to install a buffering op-amp between the ILDA connector and the modulation input to the driver.

Adam

[dave]

Yep, I have had issues much the same as what is being described, and a differential amp such as shown in fig 5 here sorted it

http://www.pangolin.com/resguide12.htm

The input impedance of the laser-wave lasers is pretty low really, but easy to get around... Bit of a no brainer really

[gottaluvlasers]

Thanks Everyone!!

Yes, We are looking into the impedance of the Lasers. This can be a significant "issue" when installing the lasers and using certain controllers. Limiting the input Voltage on a driver to <5V will obviously not yield a full output.

Dave-

but easy to get around... Bit of a no brainer really

Its a *big* yes brainer when you sell lasers to other Laser companies in the U.S. on the order of 10-30 each. Or have sales to universities for FDA certfied/certifiable lasers. Also, not everyone in this profession know what a "differnetial ampifier" is or how to make one. It is also a big "yes brainer" when you try to explain to a customer why they possibly will not get a full output on a laser that they paid for unless they build one of these, or add one of those or design one of them thingies. It is also a big yes brainer when selling lasers in the U.S. and modifying them or modifying a drive circuit will constitute a modification and therefore may violate an OEM design and furthermore may require a new product report with the CDRH.

-Marc

[Stuka]

Thanks

anyone with an o-scope also??

PM sent...

Randy

[ElektroFreak]

Thanks Everyone!!

Yes, We are looking into the impedance of the Lasers. This can be a significant "issue" when installing the lasers and using certain controllers. Limiting the input Voltage on a driver to <5V will obviously not yield a full output.

Dave-



Its a *big* yes brainer when you sell lasers to other Laser companies in the U.S. on the order of 10-30 each. Or have sales to universities for FDA certfied/certifiable lasers. Also, not everyone in this profession know what a "differnetial ampifier" is or how to make one. It is also a big "yes brainer" when you try to explain to a customer why they possibly will not get a full output on a laser that they paid for unless they build one of these, or add one of those or design one of them thingies. It is also a big yes brainer when selling lasers in the U.S. and modifying them or modifying a drive circuit will constitute a modification and therefore may violate an OEM design and furthermore may require a new product report with the CDRH.

-Marc

Yeah.. one shouldn't have to build extra circuitry to get full usage from their expensive piece of equipment. It really should be as simple as connecting the modulation wires from the laser(s) to the modulation outputs of the FB3.

[gottaluvlasers]

Electrofreak-

I agree.

Bridge and I are already working on it. Well, more Bridge than me. I dont work in his factory.

-Marc