Mysterious little red dot.

[Rosalita Gata]

Both of my Sanwu 445 nm lasers produce a dim little red dot outside the 445 nm dot. Does anyone know why.

 

[tinkertavernco]

Can you show a picture of this? I’m really interested to see.

 

[Rosalita Gata]

Can you show a picture of this? I’m really interested to see.

I went to get a photo and the red dot did not appear. Both lasers were running on low battery when I saw the dot. I didn't know this at the time. I just put in fully charged cells and there is no more dot. I'll discharge them and then get a photo.

 

[Rosalita Gata]

I went to get a photo and the red dot did not appear. Both lasers were running on low battery when I saw the dot. I didn't know this at the time. I just put in fully charged cells and there is no more dot. I'll discharge them and then get a photo.

The red dot did not make a new appearance with almost discharged batteries. If I were you I wouldn't believe me, but I swear I wasn't using any hallucinogenic drugs. I have seen it before. If it makes a reappearance, I will grab a photo.

The lasers are Sanwu Challenger II 445 nm 3 W and Sanwu Pocket 445 nm 500 mW. I have heard reports of infrared leakage with frequency doubling green lasers when they are cold. I have no idea of the cause of the red dot.

 

[Ears and Eggs]

That is really strange, hopefully if it happens again you can get a picture. With DPSS lasers like 532 or 473nm this dark red could be infrared leakage as you said, but it makes no sense with a direct diode laser like 445, or 660nm.

 

[RedCowboy]

If you are pointing your 445-465nm laser at foliage ( green leaves ) then you will see a dim reddish outline around your spot from floresense.

 

[Rosalita Gata]

The little red dot came back. It is caused by chromatic aberration of my polycarbonate eyeglass lenses. oops. Please don't flame me too hard.