Color sensor distance problem

[burak450]

I am sorry, but I dont get most of answers.HOw can I use lenses in this project?Is there any example?

I tried photodiode earlier.I didnt have right results.What kind of photodiode should I use? For example???

[skimask]

I am sorry, but I dont get most of answers.HOw can I use lenses in this project?Is there any example?

I tried photodiode earlier.I didnt have right results.What kind of photodiode should I use? For example???

http://en.wikipedia.org/wiki/Collimator

[Archangel]

Here is a crude picture of the device I mentioned.