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Combine laser beam with LED

  1. Jun 27, 2015 #1
    I want to create a visible pattern of light from 1-5 feet away. The pattern would have a bright dot in the middle (ala sniper sight) visible in bright light at 5 feet. The cheap toy pointers seem to work just fine. It would also have a filled circular pattern around the dot, 8" in diameter at 4' and visible at about 3' in bright light. I have an LED that does this fairly well with the right diversion (dispersion?) angle. Red seems to be the best color.

    So I have 2 questions
    1. How do I combine the laser beam with the LED? All of the optics needs to be packaged in a narrow tube about 1/2' in diameter. I know that a prism of some kind might work but I don't want to spend a lot of time machining down a large prism. What about a mirror with a 2-way coating?

    2. Even better, is there a way to produce this pattern with just the laser. Maybe a lens with a hole?

    This is just a hack for a toy laser 'shotgun' just for fun.
    So all ideas and criticisms cheerfully accepted.
  2. jcsd
  3. Jun 27, 2015 #2


    Staff: Mentor

    I think you'll get better answers on a hobbyist forum than on a physícs forum.
  4. Jun 27, 2015 #3
    That's kind of offensive anorlunda.

    So just because this is a fun hack for a toy, it's beneath the mean of this forum?
    Do others feel this way?

    Why would I go to a hobbyist forum for answers about optics?

    I've had some great responses here about water flow for my rainbarrels and water conservation projects. I guess I should have gone to a plumbers forum to ask about fluid dynamics.

    I guess I should have said "So most ideas and criticisms cheerfully accepted."
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