Blu-Ray dangers? Cataracts? Skin cancer?

Where does 405nm Blu-ray light fall in the UV spectrum as far as danger levels? We spend a large part of our lives avoiding UV light with sunscreen and sunglasses. Now we're willfully shining UV light, in concentrated form all around us at close range. Do we have to worry about UV damage to our skin and eyes just from diffuse reflections like off a white wall?

Someone school me on this. Does Blu-ray light fall into the UVA/UVB category, or is it something else?

I think this is important, especially as we start ramping up the power levels of our 405nm lasers!

From what ive read, 280nm-315nm is the hazard zone for skin cancer, as for the eyes I believe 405nm degrades night vision. Cataracts seem to be an IR & NIR issue.

I found some good info about the different wavelengths on wikipedia: http://en.wikipedia.org/wiki/Ultraviolet#Subtypes

It does seem like 405nm just starts to step into the UVA range which according to wiki, once was thought to be harmless but now has been proven to be something you want to avoid too. They list UVA as: 400nm - 315nm, very close to 405nm, but is that 5nm enough to equal safety??

Here's the excerpt:

UVA, UVB and UVC can all damage collagen fibers and thereby accelerate aging of the skin. Both UVA and UVB destroy vitamin A in skin which may cause further damage.[11] In the past UVA was considered less harmful, but today it is known, that it can contribute to skin cancer via the indirect DNA damage (free radicals and reactive oxygen species). It penetrates deeply but it does not cause sunburn. UVA does not damage DNA directly like UVB and UVC, but it can generate highly reactive chemical intermediates, such as hydroxyl and oxygen radicals, which in turn can damage DNA. Because it does not cause reddening of the skin (erythema) it cannot be measured in the SPF testing. There is no good clinical measurement of the blocking of UVA radiation, but it is important that sunscreen block both UVA and UVB. Some scientists blame the absence of UVA filters in sunscreens for the higher melanoma-risk that was found for sunscreen users.

405nm won't give you skin cancer or cause cataracts. Just don't shine a 90mw blu-ray at your skin for 10 hours and day and you should be fine.
You probably get more hazardous uv by going outside in the sun for 10 minutes.

Razako said:

405nm won't give you skin cancer or cause cataracts. Just don't shine a 90mw blu-ray at your skin for 10 hours and day and you should be fine.
You probably get more hazardous uv by going outside in the sun for 10 minutes.

Click to expand...

very much what I was about to say. You aren't flooding large areas of skin -or your eyes - with concentrated light.

You know how we all are so proud when we get or make our first laser that will smoke black plastic tape, or even light a match - if it's sharpied black? Compare that to placing a simple magnifying glass between the sun and a piece of paper! And you don't have to pre-blacken the paper with a sharpie...

perspective, and common sense, are as important as bright lights...[sub] :[/sub]

danq - well said!