View Full Version : can I use a pair of IR Led and IR sensor to detct objects of different color

11-18-2006, 02:28 PM
Hi all,

I am trying to use a pair of IR led and sensor to detect·colors of various targets[ same type of application as Parallax Candy Sorter].
would it be possible to use the above for my purpose.if so how. it is not possible for me to purchase a dedicated color sensor.
I am using BS2 for this project.

please advice.


PJ Allen
11-18-2006, 07:36 PM
· I guess that visible colors·probably result·corresponding I-R "luminosity", like with black & white television.· But, you can't necessarily tell the difference between colors, consistently, that way.· How well could you tell a·card of·yellow and another of white if viewed in black·& white?

· And a·card with gloss red will have a much different I-R signature than one with flat red, too.

· So, the best answer at this point is: it all depends.· Given some controlled circumstances, some modest results should be achievable.

Post Edited (PJ Allen) : 11/18/2006 12:42:13 PM GMT

Steve Joblin
11-19-2006, 02:38 AM
I don't think you will be able to get any consistent results using IR, but you can with visible light! Check out David Cook's Robot Room article on building a CADMIUM-SULFIDE COLOR SENSOR at http://www.robotroom.com/ColorSensor.html (http://www.robotroom.com/ColorSensor.html)

11-19-2006, 11:05 AM
Thank you very much.
However,I do have a webcam. so I will now use it to do image processing
using java. I will then use java.comm to communicate with the BS2 to control
the hardware part of the 'candy sorter'

if I could use a small sensor then I could have made the 'candy sorter' portable
and cheap.

thanks everyone again