LED light diffraction, scattering

  • #1
I am constructing a 'white line detector' to use on the underside of a robot. The crucial components are an ultrabright red LED and a light-to-voltage converter. My initial idea is to leave the LED as it is, i.e. unshielded. I have to light-to-voltage converter, which is a phototransistor with a lens (TSL-257), connected nearby and it is shielded using heat-shrink tubing to block out ambient light. it is being used to detect a change in color from black to white.

My question is, do I need to worry about "shielding" the LED to guard against scattering. If I just shield the TSL257, I get a voltage reading of 125mV, and when it crosses over to white, it is about 2V. This is perfectly fine, but the other members of my team want to put a heat-shrink tube over the LED as well because they think it will concentrate the light into more of a "beam". My concern is, the black heat-shrink tube will absorb the LED light and the intensity that is emitted to the floor will be weaker than if it just left alone.

Which is more justified? placing a tube over the LED or just letting it shine?

Thanks!
 

Answers and Replies

Related Threads on LED light diffraction, scattering

Replies
3
Views
371
  • Last Post
Replies
6
Views
2K
  • Last Post
Replies
6
Views
3K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
3
Views
2K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
4
Views
3K
  • Last Post
Replies
22
Views
6K
  • Last Post
Replies
3
Views
3K
  • Last Post
Replies
6
Views
3K
Top