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490 blue beauty


Nexgen

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I have one that does >488nm. I love those that are lower WL. By the way nice addition.
 
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paul1598419

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It is difficult to say from a photograph, but your laser looks more blue than green. If it looks blue and not cyan it is likely a lower wavelength Sharp diode. I am building a 487nm laser for my daughter for Christmas. She liked my 488nm one so much that I thought it might make a nice gift for her. She has a fairly large laser collection too. Compliments of her father. ;)
 

paul1598419

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I measured 30 of these diodes with a spectrometer. They all ended up being between 486.5nm and 492nm. That may not seem like much of a difference, but the ones that are 488nm and below were blue and those above 489nm were cyan in color. So, there is a difference in the color of your laser depending on its wavelength. I am currently building a 487nm laser for my daughter for Christmas. She has quite a collection of lasers now. Thanks to her dad. :D
 

paul1598419

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I have a different Sharp diode that measures 493nm that is my cyan colored one. I also have a 502nm Sharp diode in a build that is still green, but looks blue next to any other green laser I have.
 

RedCowboy

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Nice, I enjoy my 488 as well, is it green or is it blue, turn on a 405nm next to it and now it looks different still, :LOL: perception based on surroundings make it tricky but it is a cool chameleon wavelength to start with.
 

paul1598419

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My 477nm laser is among the ones I have that remain blue no matter what you compare it to. My 488nm looks blue to me until I compare it to my 477nm one, then it starts to look a bit cyan. I hope to finish my 487nm build today that will end up going to my daughter. At least everything I'll need is sitting on my bench.
 

paul1598419

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Looks badly out of focus from what I can see from your photo. Have you tried to collimate your laser with this lens? You may have it in backwards. The lens is at one end of the housing and that goes toward the diode. You may also see a slot on one side and that goes away from the diode. One thing you may not know about these Sharp diodes is they have a rectangular artifact on the side of the collimated dot especially with short focal length aspheric lenses. The only lenses to eliminate it is the acrylic lens that comes with any 12 mm module or the two element 520nm AR coated lens from DTR.
 

paul1598419

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The lens is in the correct way as it's only got 1 groove for the spring
I don't understand what you mean. That lens can be screwed into the module from either side, so it is possible to put the lens in backwards. If you look at your G2 lens housing you will see the lens is at one side. That is the side that should go in first toward the diode. Once you do get it collimated you will see a rectangular artifact at one side of the dot it makes on a surface.
 




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