[PICS] Driver with Modes: WITHOUT A Controller!

[Wolfman29]

Actually, I was reading through old threads of mine, and that was an idea I had a LONNNGGG time ago. But I figured that not many people would be particularly interested since most hosts wouldn't accommodate that. Maybe I can work with one of the machinists around here and see if we can get a cheap host going that would be good for that.

 

[Atomicrox]

That's a great idea. I'd certainly be interested, provided the price isn't too high (I'm not into "high-end" hosts).

 

[Wolfman29]

Well, it would all depend on the pricing the machinist would want to set for the host. I am sure I could do some sort of driver like that for <$25 pretty easily.

 

[Atomicrox]

Sounds great!

 

[Cyparagon]

@Cyparagon: the problem with PWM is that it doesn't make the low power modes eye-safe(r).

Not true. Think about average power. You might think a 100mW beam is dangerous. But if it is only active for a few microseconds, the beam simply cannot transfer enough energy to cause any damage.

Read wikipedia's MPE article.

 

[Wolfman29]

This is very true. Why do we often see that analog control is "better" than TTL though? Just curious. Because TTL is essentially PWM, is it not?

 

[Atomicrox]

For the sake of the argument, if we consider only average power an Arduino could PWM a 2.56W laser to a safeish level of 10mW, on minimum power and 8-bit PWM.

But notice the MPE graph isn't very steep. We need to do the math to see which frequency would be needed for it to be as safe as a 10mW pointer.