zyxwv99
0
- Joined
- May 6, 2013
- Messages
- 178
- Points
- 0
:wave:I've been here for a few months but never got around to introducing myself. Ever since I was young I've been interested in science, reading Scientific American and the sort of books they advertize. I had a brief interest in lasers in the 1970s, but never followed up on it until now. I am very new to laser pointers.
My current interests center around light, color, and vision. For example, how many milliwatts would it take for a 405nm violet laser to look as bright as a 5mW 532nm green? According to the most widely cited authority (CIE 1931) it's 6.7 watts. However, CIE 1931 has problems below 460nm which were corrected in CIE 1978. According to the corrected version, it only takes 925mW.
Then there's the question of how far into infrared and ultraviolet people can see. It turns out people can see not only infrared but even microwaves up to 1050nm. However, those last 100 nanometers are best left to vision researchers, most of whom are eye doctors. For regular folks, 940nm is about as far as you would want to go. At the other end, people can see down to 250nm, but the last 65 nanometers should be viewed only under the supervision of an eye doctor.
Or, as they used to say at Boy Scout camp: "Stop! You'll go blind!"
My current interests center around light, color, and vision. For example, how many milliwatts would it take for a 405nm violet laser to look as bright as a 5mW 532nm green? According to the most widely cited authority (CIE 1931) it's 6.7 watts. However, CIE 1931 has problems below 460nm which were corrected in CIE 1978. According to the corrected version, it only takes 925mW.
Then there's the question of how far into infrared and ultraviolet people can see. It turns out people can see not only infrared but even microwaves up to 1050nm. However, those last 100 nanometers are best left to vision researchers, most of whom are eye doctors. For regular folks, 940nm is about as far as you would want to go. At the other end, people can see down to 250nm, but the last 65 nanometers should be viewed only under the supervision of an eye doctor.
Or, as they used to say at Boy Scout camp: "Stop! You'll go blind!"
:angel:
