color palette sulution rgb intensity on one card

color palette sulution, analog: rgb and intensity from one LD2000 card

Hi
I'am looking all day solution how to make analog palette for green and rgb lasers all analog on one card. When I configure palette for color then have ttl o intensity pins. When use one color palette works fine but only on green laser. Is there any trick work both of lasers in analog?
Im found this:
"http://www.pangolin.com/forums/showthread.php?t=102&highlight=palette"
there is a link to solution, but doesn't work:
"http://pangolin.com/cgi-bin/ultimate...c;f=1;t=000033"


thanks
 
Last edited:
We have been interacting via email on this point.

If you simply want to have analog output, then it's really so simple, and there are even a few ways to do this.

One way (the easiest) is to tell the system that you want "single channel color" -- not TTL color, but "single channel color". The LD2000 wizard will then present three sliders which you use to setup the range and response of the laser.

Another way (just a touch harder) is to tell the system that you want "multi-channel color", but when LD2000 presents you with the "colored chips" for each color channel, you only click Green on one of the color chips, and indicate all of the others are black. LD2000 will then present you with up to four sliders with which you can adjust for an analog range.

HOWEVER, I believe our email exchange painted a more complicated picture -- wanting to use the same QM2000 card for one laser which is RGB, and another that has only a single laser (i.e. two separate lasers connected to a single QM2000). This is possible to accommodate, but manual training is needed.

Note that the absolute best way to do this is not with the software at all, but rather with three diodes inside the laser projector itself -- the three diodes being placed on the red, green, and blue inputs, and forming a single output which you use to drive the laser. Using this "diode" technique will allow you to connect the laser projector to literally any ILDA signal source in the world and have success.

Best regards,

William Benner
 
Hey Bill,

Would the diode just be a standard rectifier diode like the 1N4001 or similar?

Cheers
Rich
 
It is best to use a Schottky diode or even Germanium diode (available at radio shack) for this purpose. These will only drop around 0.2 volts.

HOWEVER, everyone should understand that even if you use 1N4001 power supply diodes, this will generally NOT result in a power loss. The reason is because many laser diode drivers saturate at (surprisingly) around 2.5V to 3V. So feeding 4.3V into a driver generally does not deliver much less power.

MOREOVER, your eye has a logarithmic brightness response with base of 4 or 5. It means you need to reduce the power to 20% for your eye to perceive that the brightness is 50%. This is another reason why the difference between 4.3V and 5V should not be noticeable.

Best regards,

William Benner
 
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