I have a couple 520nm diodes, a PLP-520-B1 and a NDG7475, and I've noticed that their dots look yellow when viewed through red-tinted low-wavelength-blocking goggles. Now, of course we all know that red and green make yellow, so what is the issue? My eyes are clearly seeing the combination of red tint and green light to perceive yellow!
The problem comes when I shine the laser through the goggles themselves. Green goes in one side, and is almost entirely blocked, but a golden yellow comes out the other side. To keep from burning my goggles, I used a beam expander to spread the width at aperture and a cheap pair of Ebay-Specials:
Image may be NSFW.
Clik here to view.
It is not scattered, either! I can easily focus the light down to a point, seen here close up
Image may be NSFW.
Clik here to view.
It is on the order of a milliwatt or two, judging by eye. I even ran it through a diffraction grating to see if it was some odd combination, but it came out as one wavelength. My question is this: What's coming out of my laser?
The problem comes when I shine the laser through the goggles themselves. Green goes in one side, and is almost entirely blocked, but a golden yellow comes out the other side. To keep from burning my goggles, I used a beam expander to spread the width at aperture and a cheap pair of Ebay-Specials:
Image may be NSFW.
Clik here to view.
It is not scattered, either! I can easily focus the light down to a point, seen here close up
Image may be NSFW.
Clik here to view.
It is on the order of a milliwatt or two, judging by eye. I even ran it through a diffraction grating to see if it was some odd combination, but it came out as one wavelength. My question is this: What's coming out of my laser?
