I am pretty interested in getting a portable blue 473nm at about 20mw. I have looked at the optotronics rpl-20, but $929 is just too much for me. :-/ Does anybody know a place where I can get a cheaper portable blue at around that power range? And how is the visibilty of it compared to green at the same power?
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Cheaper blue laser?
- Thread starter lazerguy
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Razako
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Here's a guy selling a used 20mw blue for $450 shipped.
http://www.laserpointerforums.com/forums/YaBB.pl?num=1201215211
http://www.laserpointerforums.com/forums/YaBB.pl?num=1201215211
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At night the beam is said to be brighter than 20mW of green because it is closer to Scotopic vision's peak at 507nm.
i keep hearing that at night 20mw of blue appears brighter than 20mw of green but honestly, i dont think you can compare them at all, green is still way brighter than blue. to me, 20mw blue is about the same as 5mw green.
by the way, i dont have the 20mw blue anymore, its gone
by the way, i dont have the 20mw blue anymore, its gone
lazerguy said:
What do you mean by that styropyro? What is scotopic vision? i have heard that the eyes peak sensitivity is at 555nm.
[/quote]
Black'n'white vision. You must of course know that your vision in the dark is completely different from vision in the light.
darklandz said:i keep hearing that at night 20mw of blue appears brighter than 20mw of green but honestly, i dont think you can compare them at all, green is still way brighter than blue. to me, 20mw blue is about the same as 5mw green.
by the way, i dont have the 20mw blue anymore, its gone
The eye is most sensitive to a certain wavelength of green, not blue.
The actual sensitivity peaks at around 507nm, somewhere between bue and green but more green.
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But at lower wavelengths the beam seems to be brighter at the same power. I've read a few posts on here saying that their blue's beam at night was as a bright as a greenie. If you have a 5mW-10mW blu-ray you will know that the beam at night is pretty brighter for such low powers.
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bob1122 said:[quote author=darklandz link=1208119791/0#4 date=1208136684]i keep hearing that at night 20mw of blue appears brighter than 20mw of green but honestly, i dont think you can compare them at all, green is still way brighter than blue. to me, 20mw blue is about the same as 5mw green.
by the way, i dont have the 20mw blue anymore, its gone
The eye is most sensitive to a certain wavelength of green, not blue.
The actual sensitivity peaks at around 507nm, somewhere between bue and green but more green.[/quote]
At night. During the daytime peak visibility is 555nm.
Your eyes have different types of cells, rods and cones. I forget which is which, but one is sensitive to black and white whereas there are 3 types of the other for red, green and blue. The colour ones are not nearly as sensitive as black and white, and some colours are not as sensitive as others.
This is why at night, you can sometimes see very faint stars by looking next to them in the sky.
This is also why night vision is totally different to daytime vision.
BlueFusion said:[quote author=bob1122 link=1208119791/0#8 date=1208170104][quote author=darklandz link=1208119791/0#4 date=1208136684]i keep hearing that at night 20mw of blue appears brighter than 20mw of green but honestly, i dont think you can compare them at all, green is still way brighter than blue. to me, 20mw blue is about the same as 5mw green.
by the way, i dont have the 20mw blue anymore, its gone
The eye is most sensitive to a certain wavelength of green, not blue.
The actual sensitivity peaks at around 507nm, somewhere between bue and green but more green.[/quote]
At night. During the daytime peak visibility is 555nm.
Your eyes have different types of cells, rods and cones. I forget which is which, but one is sensitive to black and white whereas there are 3 types of the other for red, green and blue. The colour ones are not nearly as sensitive as black and white, and some colours are not as sensitive as others.
This is why at night, you can sometimes see very faint stars by looking next to them in the sky.
This is also why night vision is totally different to daytime vision.[/quote]
rods = black'n'white
cones = colour
I'm surprised nobody has mentioned a homebrew blue laser yet.......of couse this is a matter of preference.. BUT $100 or so can be alot more appealing than $900.
Building one requires patience and general mechanical/electronics knowledge, but can be a rewarding experience. I am soon to build my first red(I have one from Jake21 that I think is quite nice), then will be venturing into building a blue.
OR, check the buy,sell, and trade area. There have been a few homebrew blues on there lately.. Some of the lower power(PS3 diode) setups have actually been found to burn. The 6x bluray burner variety is quite expensive(but a very cool burning laser) right now because of the cost of the bluray burning drive.
Building one requires patience and general mechanical/electronics knowledge, but can be a rewarding experience. I am soon to build my first red(I have one from Jake21 that I think is quite nice), then will be venturing into building a blue.
OR, check the buy,sell, and trade area. There have been a few homebrew blues on there lately.. Some of the lower power(PS3 diode) setups have actually been found to burn. The 6x bluray burner variety is quite expensive(but a very cool burning laser) right now because of the cost of the bluray burning drive.
Glaserfan said:
The PS3 diode is a purple/violet color(405nm), by blue laser, he means a laser with a 473nm wavelength, not 405nm. I don't believe that you can build your own 473nm laser yet, but if you could, it would probably cost more than buying it from someplace like Optotronics or LaserGlow.
