Building an (IR) infrared-veil

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By Phillip Torrone
Posted 2006/01/27 @ 3:00 am
Category Electronics

Yallla writes “For the 22C3 some people from Vienna conducted some CCTV wiretapping experiments; in a sidenote they said that infrared light is disturbing CCTV cameras. I’m now conducting experiments about how you could exploit that feature of CCD-sensors to create some kind of infrared-veil – like a basball cap full of IR transmitting LEDs, spoilng the CCTV footage experience of your airport security staff. Goals of my experiments are if it’s really working, what type of LEDs are suitable and what happens to me in real life when i just say “Shields up!!” Link to the MAKE forum post – project page.

In the Maker Shed

6 Responses to Building an (IR) infrared-veil

nitsogar on January 27th, 2006 at 11:27 am said:

IMHO, if the IR leds you intend to use are similar to those is a TV remote and security cam CCD’s work/are the same as those in digital still cameras you won’t really disapear you’ll just glow… attracting attention, not disapearing as you would like.

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adricm on January 27th, 2006 at 12:00 pm said:

ive been looking into this, took some IR led’s and replaced the ones in a bike safety strobe, found mixed results, if the leds are pointed at the camera the fast srobe causes some cameras to auto-iris (like it was taken out into daylight) making everyone else in the picture dim!

the strobe is quite noticable, but if more bright/effective it could help.. i was thinking of making a pair of blinking sunglasses

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super_J_dynamite on January 27th, 2006 at 12:58 pm said:

Most CCD based cameras have filters to block IR light precisely because it’s not necessary for taking pictures (it’s not in the human visible range) and it is readily picked up by CCDs. So any solution you create would have to work against that.

Using a remote control and a digital camera I’ve noticed that, when pointed directly at the lens, I can see the IR LED blinking, but when turned away, it doesn’t illuminate like a flashlight.

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yalla on January 27th, 2006 at 1:06 pm said:

I’m just trying to investigate if the whole idea is doable at all; if it isn’t – dump it. If it works to some extend: Might be fun to explore the results in reality!

Of course i know that pointing the LED directly at the lens brings other results than taking pictures of *reflected* IR-light. This is something i want to investigate.

The wanted/expected result should be: Blank out face with mighty IR-power. Will it work? I have absolutely no idea. We’ll see

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StayPutNik on January 27th, 2006 at 2:20 pm said:

what works a lot better than IR leds would be a flashlight with an IR filter in front of it. people have successfully made invisible spotlights for use with night vision cameras this way. see here…

almost all ccds have an IR filter that blocks out most of the infrared, but you can still see a remote control’s led blinking because it doesn’t filter all of it. with a strong enough flashlight, you could probably overwhelm the camera, filtered or not…

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yalla on January 27th, 2006 at 2:27 pm said:

The IR-filter/flashlight idea is not too bad – although i will mainly focus on my initial idea. Don’t want to loose track right at the beginning of my project

However, will investigate that later. Prolly a strobosscope with an attached IR-filter will really screw up CCTV.

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