← Back to context Comment by brcmthrowaway 21 hours ago Does anyone know of a lens that can make a laser look like a spotlight? 2 comments brcmthrowaway Reply dekhn 18 hours ago More details required.Like the other comment says, this can be done with a beam-expanding telescope (which can be as simple as two lenses whose focal length ratios determine the magnification). https://www.newport.com/n/how-to-build-a-beam-expander and https://www.thorlabs.com/an-example-of-a-diy-keplerian-beam-... are a good place to start.But it can be a bit more complicated than that , and it's often easier to use an LED. aj7 21 hours ago Look up “beam expanding telescope.”
dekhn 18 hours ago More details required.Like the other comment says, this can be done with a beam-expanding telescope (which can be as simple as two lenses whose focal length ratios determine the magnification). https://www.newport.com/n/how-to-build-a-beam-expander and https://www.thorlabs.com/an-example-of-a-diy-keplerian-beam-... are a good place to start.But it can be a bit more complicated than that , and it's often easier to use an LED.
More details required.
Like the other comment says, this can be done with a beam-expanding telescope (which can be as simple as two lenses whose focal length ratios determine the magnification). https://www.newport.com/n/how-to-build-a-beam-expander and https://www.thorlabs.com/an-example-of-a-diy-keplerian-beam-... are a good place to start.
But it can be a bit more complicated than that , and it's often easier to use an LED.
Look up “beam expanding telescope.”