Laser noise

[Samuel M. Goldwasser]

zekfrivo@zekfrivolous.com (GregS) writes:

In article <ubpeyfj15.fsf@repairfaq.org>, sam@repairfaq.org (Samuel M. Goldwasser) wrote:
zekfrivo@zekfrivolous.com (GregS) writes:

In article
f85b3ee2-2adb-43e9-a16f-825259a9ed24@w27g2000pre.googlegroups.com>, Robert
Macy <macy@california.com> wrote:
On Mar 4, 4:01=A0pm, s...@repairfaq.org (Samuel M. Goldwasser) wrote:
Meat Plow writes:
What about using a lens to spread the light?
Wouldn't that effect or distort the noise or influence the reading
otherwise?

Not as long as the noise relative to the total power into the sensor
is what's measured.

--
=A0 =A0 sam | Sci.Electronics.Repair FAQ:http://www.repairfaq.org/

Pre-apologize for the naive question:
Are you measuring amplitude noise and/or spectral noise?
Are these valid questions?

I'm mostly concerned with power supply noise or whatever is predominant.

What type of laser are you using (sorry if I forgot!)?

If it's a diode laser, looking at an electrical signal from the power supply
that corresponds to the laser diode current may be nearly as good as looking
at the laser's output and doesn't require a sensor.


Right, but getting to the right point is somewhat of a risk. I don't want to send anymore lasers back to China.

Maybe best to just leave them there in the first place.

--
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