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ArcticMyst Security by Avery

Post your TTL vs analog modulated pics:)

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And if possible, your lpm readings. I get like 500mw under normal analog modulation with my 445nm m140 diode. (drawing a circle with about 30 points or so). If i copy that event 50 times over, the laser runs at full voltage, at what it would do at tll, full power. Then i get 1500mW.
So thats about 3 times lower then full power.
I dont have pics now:)
Share your results please:)
 





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As far as I know there are only a few projector owners
on LPF.
There are a lot more Projector Jockeys over on PL....
That Forum would get you a ton of info about your
questions...


Jerry
 
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Benm

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I get like 500mw under normal analog modulation with my 445nm m140 diode. (drawing a circle with about 30 points or so). If i copy that event 50 times over, the laser runs at full voltage, at what it would do at tll, full power. Then i get 1500mW.

Have a look at whats going on electronically before measuring output power.

If you get 150 mW average on ttl, compared to 500 mW on analog, you should see a duty cycle of 30% in the modulation. Hook up a scope to the ilda signal to see if its already that low there, and if it is isn't, look at the driver output current/voltage.

Is there any blanking in your pattern at all, or does it keep the laser power up when going between the points?
 
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I dont have a duty cycle. It runs 40 mins straight on 1500mW, when it runs at full voltage/power. When only scanning a circle of 30 points it doesnt give the diode full voltage/power, making the laser weaker. Im then getting only 500mW or so.
I dont think you understand what i said, or i didnt understand you:p
 
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I dont have a duty cycle. It runs 40 mins straight on 1500mW, when it runs at full voltage/power. When only scanning a circle of 30 points it doesnt give the diode full voltage/power, making the laser weaker. Im then getting only 500mW or so.
I dont think you understand what i said, or i didnt understand you:p

Seems like that's the case as it seems to me that benm has it dead on the money. The reason you're not seeing full power is because the laser is under modulation even when drawing your circle. That means it's off part of the time while it's drawing the circle. That "off time" causes your power reading to be lower as the LPM is basically showing you the average power. I doubt that your laser is actually getting less voltage on the modulation input.
 
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"If you get 150 mW average on ttl, compared to 500 mW on analog". If a analog laser set to ttl....it will put out full power. You cant then get more power???
Thats why i am confused about benm's post.

ok maybe it received desame voltage, but i sure kmow the brightness is waaaaay brighter with that same circle event copied over 50 times.
 
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Ok I think I see what you're saying.. sorry I misunderstood. I think when you talk about "that same circle even copied over 50 times" you're overlaying more and more points, resulting in more brightness.
 
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Ok I think I see what you're saying.. sorry I misunderstood. I think when you talk about "that same circle even copied over 50 times" you're overlaying more and more points, resulting in more brightness.

So it basicly means the brightness gets higher because it doesnt "pause" the scanning because all the copied points?

Always thought the galvo didnt need to pause at a cirle since its a well....round image. Nothing else so youd say it can keep turning without turning off...?
 
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Benm

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There is no reason it -has to- pause when drawing a circle - it could just keep the laser on and move the mirrors around at the maximum speed they can handle, in 'ballistic mode' so to say.

But if you have -some random- ilda frame that draws a circle, it is not certain that it draws that way. It could put down dots that form a circle, or draw the circle and blank for a while, or whatever the designer of the frame figured to be appropriate.
 
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I drawed it myself in LSX, so i do think it doesnt need to pause. But again copying over the event alot of times will make the lasers ALOT stronger. So it does have to do with voltage then? The more dots the more lsx feeds the ilda signal more voltage?
How does other software behave if yes...
I rather have more power ofcource in modulation...even at simple events.
 




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