Will slightly damaged lens reduce power?

[laze_doctor]

.....

 

[rangedunits]

It does definetly have an effect.

 

[LarryDFW]

laze_doctor;

The artifacts you noticed are probably just dust either on the window of the laser diode (if it is a closed can) or on the collimating lens itself.

Unless they cover a significant portion of the field of view, they have very little effect on the total power output.

I use ultrasonic immersion solvent baths to clean my lenses.

Much quicker & safer than disassembly.

LarryDFW

 

[jeffd]

Yeah take your lens off and turn on your laser, you should still be seeing the same artifacts.

 

[Jimmymcjimthejim]

I took the lens out for cleaning

How did you clean it? Also, if the lens is truly glass, then it is not likely to be scratched. Dust is a very common thing and can easily be taken care of. I use a squeeze bulb to puff air at the lens, then gently rub the lens with a lenspen, and finally use the squeeze bulb again. Works every time.

 

[Crazy Jay]

Do you use a spring?

 

[Crazy Jay]

Yeah I do use a spring. I've tested it without the spring though, and same deal. Why do you ask?

Why do you think I asked?

To see if it was the spring that was causing it.


On a side note I think perhaps the artifacts are unnoticeable on the laser and that the lens, somehow makes it visible.
What other explanation is there?

 

[jayrob]

As was mentioned, it doesn't sound like anything that will affect the output power to any degree...

It is possible that the dust is on the diode window. (if it is a canned diode)

 

[Deleted member 8382]

remember that the dot is nothing else than the "big" circle when unfocused being "focused", so yes, being reduced to a point. If you could look at it properly you would still see the black dots inside it. Obviously if there are black zones there are zones with no light and so the power is affected.

 

[nikokapo]

Hey folks,

So it looks like I have damaged the meredith lens on my red laser.

I was looking at the dot while it was completely defocused and I noticed artifacts in the dot -- like tiny impact craters in the glass surface.

These are imperceptible when examining the lens itself under a bright light, but when the laser is projected through it, it magnifies the damaged areas of the glass.... they're only visible when the laser is completely unfocused, and it still focuses down to a nice clean point.

I took the lens out for cleaning, and noticed a few barely perceptible hairline scratches -- probably caused by my removal of the actual glass lens from the AixiZ nut.

So the question is, is this minor damage likely to have an impact on the power of my laser? I won't have access to a LPM until next year, so no way of knowing for sure. Should I just buy another lens and not mess with it this time?

I realize it's probably a very difficult question to answer for sure. But any general opinions would be appreciated!

Theoretically you will lose power even if there's a 1 micrometer fissure on the surface. That is because light will bounce inside of it and will be "lost" by being absorbed by the lens and nut walls. If you're wondering if it's really going to have an impact on power readings, don't worry, you'll lose 1mW at the most.