making LEDs brighter
David
safe way to look into crevices, behind furniture etc.
So I bought a thing called a 'Snake' (coincidence hey) which is a camera
on the end of a long flexible tube, which connects to the USB input of a
Windows computer and allows you (well me actually) to either take a
snapshot of the area or watch live video.
In order to illuminate the area for the camera there are two LEDs
mounted on the end of the tube - a pot controls the brightness of these.
The problem is I need to look into very dark areas, and the LEDs just
don't light up the area enough to allow clear vision.
It would be very difficult to replace these, so are there any
suggestions on how I can increase the brightness of them - reduced life
would not be a problem.
Ideas greatly appreciated
David (walking very gingerly around his house)
Sylvia Else
If it's for a one-off purpose, couldn't you just stick some extra ones,
and the wires to power them, onto the outside of the tube with sticky
tape? Power them off a small battery, with approriate resistors.
Sylvia.
David L. Jones
LEDs are current driven. Over a certain upper rated current, you just
shorten the life of course, and of course total failure at a point. But you
get a pretty much a linear increase in lumens output vs current.
So measure the current consumption and then add your own constant current
driver to drive the LEDs, driven from the 5V USB power.
How much extra light do you recon you need? If it's double, that should work
just fine. If it's 10 times then it's not likely you'll get what you want
out of the existing LEDs.
Can't you just tape on some new LEDs to the outside of it?
Dave.
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David
"David L. Jones" <alt...@gmail.com> wrote:
> David wrote:
\
>
> How much extra light do you recon you need? If it's double, that should work
> just fine. If it's 10 times then it's not likely you'll get what you want
> out of the existing LEDs.
>
> Can't you just tape on some new LEDs to the outside of it?
>
> Dave.
As both you and Sylvia have suggested I guess that is the best way to do
it - so thanks to both of you
David
Jasen Betts
if you can find the resistor (inside the sanke somewhere) that sets the
current the LEDs get you could try reducing it
Sylvia's idea is probably better.
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ian field
"David" <post...@REMOVE-TO-REPLYconfidential-counselling.com> wrote in
message news:postings-B4DEB9...@news.bigpond.com...
The traditional way to boost the apparent brightness of LEDs is to pulse
drive them, search for data sheets and application notes for more info, even
if you can't identify the LEDs in your device you should be able to find
some info on how to manage M/S ratio and peak current for "generic types".
Pulsating light might also disturb the snake more than steady light, making
it more likely to move and give its position away.
who where
<gangprob...@ntlworld.com> wrote:
>The traditional way to boost the apparent brightness of LEDs is to pulse
>drive them, search for data sheets and application notes for more info, even
>if you can't identify the LEDs in your device you should be able to find
>some info on how to manage M/S ratio and peak current for "generic types".
>
>Pulsating light might also disturb the snake more than steady light, making
>it more likely to move and give its position away.
It provides only "apparent brightness" reliant on the human eye's
peak detection behaviour. That doesn't work in the context of
illumination for (e.g.) a camera.