Re: Using piezoelectric to power a laser diode?

Walter Harley wrote:
> <bobrich@xxxxxxxxx> wrote in message
> news:1138384788.550275.201020@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> > John,
> >
> > All i can say is holy cow! I didn't expect schematics!!! I'll have to
> > give that a try!
> >
> > The illumination just has to be long enough for the human eye to detect
> > it, which i'm assuming is going to be a function of brightness, but at
> > 5mW i'm assuming 20-50ms is plenty..(my 200 upper end range is on the
> > long side)...lots of assuming though, eh?
>
>
> You're aiming a 5mW laser at a human eye?

Nooooooooo. I thought i fixed that part of my post...sorry. I'm just
basically building a laser pointer for a little personal project. The
piezo power idea came from the desire to make it as compact as
possible, with the longest shelf life i can muster. In addition, the
chassis that this is mounted in will be moving kind of vigorously, so i
want to capture, in essence, a 'flash' that a person can see through
persistence of vision...rather than a continuous beam which would
rapidly become ambigous due to aforementioned motion.

The laser will, under almost any conceivable circumstance, be aimed at
a wall or 'calibrated' paper area so we can see how much the chassis
has deflected.

The application would be analagous to setting a similar device in the
head of a golf club. The laser is parallel with the club face, and
'flashes' upon impact with the ball. The position of the flash
relative to the alignment of the tee with the player will detect how
much slice or hook is in the swing.

Bad example, but it gives you an idea of what i'm trying to achieve.

>You can easily see a 1 usec puls from a normal (high efficiency) white
>LED, at 100 mA.
>Stef

That's good info, thank you. I wasn't sure how much of a duration i
would need for it to be effective. I'm assuming the laser diode would
essentially have the same characteristics...the shorter the pulse, the
better.

John, if you're still hanging around...one quick question regarding the
schematics you wrote up. In the onces with Vcc, is that an external
power supply, and the piezo is just used to switch?



Thanks everyone for your replies!!!

.

Relevant Pages

  • Re: Anyone Want To Recommend...
    ... John wrote: ... I need to print a ton ... > A laser would probably have the lowest running costs. ... "Canon inkjets usually fare better than HP or Epson." ...
    (comp.cad.solidworks)
  • Re: Possible Future States of the US Navy
    ... John P. Mullen wrote: ... > Remotely piloting a craft is a bit tricky. ... the drone could be another laser back to sensors on the ship. ... What do navies do about jamming now? ...
    (sci.military.naval)
  • Re: High Speed Differential Driver
    ... >VCO is capacitor coupled into MMIC input pin ... >MMIC output also cap coupled to laser anode. ... adjust V2 for DC laser current. ...
    (sci.electronics.design)
  • Re: Anyone Want To Recommend...
    ... >> A laser would probably have the lowest running costs. ... >> John H. ... > "Canon inkjets usually fare better than HP or Epson." ...
    (comp.cad.solidworks)
  • Re: Apple II Reference Manual Addendum PDF now online
    ... Did anyone else have problems reading the schematics pages once they ... I dumped mine to a 600dpi laser and couldn't read much. ...
    (comp.sys.apple2)
Loading