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From: "Bob May"
Subject: Re: Increasing IR LED Output
Date: Sat, 5 Oct 2002 22:03:11 -0700
Organization: NetHere Inc.
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Yes, you can get higher peak powers out of a LED but there's problems.
First, you have to syncronize the pulses to the camera's field rate which is
a fair bit more electronics.
Second, the relatively low rep rate of the fields tends to not provide as
much light as much higher rep rates.
Third, you lose light during the off time of the LED and have to make that
up during the on time which is running into problems there. The light
output doesn't act linearly with the increase of current The probability
is that you will actually end up with less total power to the CCD is very
strong by doing this.
In the end, it is usually better to just put more IR LEDs into the light
source rather than finessing with modulationg the LEDs. Brute force does
sometimes just work better.
What I want to know is when I can start growing wheat in Greenland again!
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