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ArcticMyst Security by Avery
can i make an ir laser from a green laser
- Thread starter xXDUNNXx
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No - it wouldn't focus well, because the refractive indexes for 808nm and 1064nm are very different from 532nm. Further, the diode used in those lasers is not a single-mode diode, in that it's divergence, even with collimation, is terrible, and very rectangularly shaped.
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The difference in refraction just means the beam size will be different.
The problem lies in that the only convex lens in many of the cheap pens is part of an expansion telescope, and thus has a longer focal length. The long focal length means the 808nm beam will be large - so large that it probably won't fit on the lens. You would have better results using a different lens.
You'd get about 400-500mW of dangerous IR that doesn't burn as well as you might expect.
The problem lies in that the only convex lens in many of the cheap pens is part of an expansion telescope, and thus has a longer focal length. The long focal length means the 808nm beam will be large - so large that it probably won't fit on the lens. You would have better results using a different lens.
You'd get about 400-500mW of dangerous IR that doesn't burn as well as you might expect.
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Benm
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The problem is mainly the multimode part - you'd get a 'block' output pattern instead of a nice dot/circle with bad divergence. Its still possible to focus that down to a small area at close range for burning/cutting/etc, but won't do you any good at long range.
If you want a near IR laser, you could try the CD writer diode thats also present in DVD writers/sleds. It is not very powerful (maybe 50-100 mW?), but it is single mode and could be used just like a red diode. Beware that 780 nm is barely visible though!
If you want a near IR laser, you could try the CD writer diode thats also present in DVD writers/sleds. It is not very powerful (maybe 50-100 mW?), but it is single mode and could be used just like a red diode. Beware that 780 nm is barely visible though!
