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Electronics => Electronics => Topic started by: vipulan12 on October 11, 2013, 11:38:55 AM

Title: IR leds in night vision
Post by: vipulan12 on October 11, 2013, 11:38:55 AM

can any camera be used to pick up the infrared light at night?
does the camera need to only pick up black and white for this to work? can i use any camera like a webcam?
also could i use any ir leds in remotes to build an infrared camera?

thanks

Title: Re: IR leds in night vision
Post by: waltr on October 11, 2013, 01:21:31 PM

The sensor in digital camera are sensitive to IR but many have IR blocking filers built in. These filters may be a separate optical part or more likely in low cost cameras is a coating on the lens. Some do not have an IR blocking filter.
Try to find the spectral response of the camera from it data sheet to see what its response to IR is.

Typically only B&W cameras respond to IR. Color cameras have RGB filter over the pixels to only pass that color (wavelength). However the Red pixels could have a good response to IR. Again typically there is an IR blocking filter.

The older Web cams had a separate IR filter that could be removed. Newer ones tend to have the IR blocking coating on the lens. Again look at the spectral response of the camera from it data sheet to see what its response to IR is from any camera you are considering.

A source of info about various Web Cams and low cost cameras can be found by searching for Web Cams used in Astronomy. Here is one site:
http://homepage.ntlworld.com/molyned/web-cameras.htm (http://homepage.ntlworld.com/molyned/web-cameras.htm)

Here is a tutorial showing how to mod a web cam for IR.
http://www.instructables.com/id/Infrared-IR-Webcam/ (http://www.instructables.com/id/Infrared-IR-Webcam/)

Do more google searches as there is a good amount of info out there on this subject.

Lastly, you may need to experiment to see how well any camera works with IR illumination.

Title: Re: IR leds in night vision
Post by: vipulan12 on October 18, 2013, 04:18:46 PM

is this similar to what they use in the military?
what would be the difference?

Title: Re: IR leds in night vision
Post by: waltr on October 19, 2013, 10:23:25 AM

Some military 'night vision' systems are like this others use active amplification with special sensors.
See:
http://en.wikipedia.org/wiki/Night_vision#Night_vision_goggles (http://en.wikipedia.org/wiki/Night_vision#Night_vision_goggles)

Title: Re: IR leds in night vision
Post by: gerard on October 20, 2013, 12:46:13 PM

you can easily make a night vision camera with a webcam and some ir leds
i have done this several times

take apart a webcam and unscrew the front focusing lens
there will be a small glass square behind it that is a shiny tinted colour - this is the ir filter
pull that out using a small screw driver
put the camera back together and youre done!

now all you need to do is glue on some ir leds and you will be able to see the ir light through the webcam
you can get your own ir leds from tv remotes or rc toys that use ir leds instead of antennas
i suggest getting a cheap >$50 webcam, if you dont need hd

Title: Re: IR leds in night vision
Post by: vipulan12 on October 25, 2013, 04:36:36 PM

do you know of any webcams where i can do this easily, i would really hate to do this to a webcam and realize that removing the ir Filter may result in destroying a component in the process
which camera would be good for this application?