Are Polycarbonate Sunglasses Effective Against UV Rays?

[Aeronautic Freek]

Is sunglasses test with UV flashlight correct or not?

 

[Vanadium 50]

If it's not worth your time to summarize a video, why is it worth our time to watch it?

 

[Aeronautic Freek]

If it's not worth your time to summarize a video, why is it worth our time to watch it?

https://www.quora.com/How-can-I-tell-if-my-sunglasses-are-UV-protected
"The only way to really know is to take then to an optical shop and have then measure the UV transmittance

The UV flashlight method makes a lot of sense but is not accurate.

I bought a bunch of knock-off sunglasses while travelling. I was worried about UV protection and bought a UV light. Some didn't pass the test (see other answers to know what I'm talking about with the flashlight).

Then I took them to an optical shop and had them tested on the two instruments they used. They all tested 100% UV 400 protective. The Irish technician did show me a pair he had that was not protective. They were knock off Ray Ban's with yellow lenses, and they were still a bit better than 50% protective.

Why the UV flashlight doesn't work I don't know. I suspect it's because high frequency light within the visible spectrum (and hence not UV) is still emitted from these flashlights (you know they emit some non-uv light because you can see some of the light they emit), still causes the special UV ink to glow.
"

Spectometer show that galases are 100% protective but test with UV flaslight don't pass,why?

 

[Vanadium 50]

What UV flashlight test?

Again, you're making us try and figure out what you are talking about. Instead you should ask a clear question.

 

[pinball1970]

https://www.quora.com/How-can-I-tell-if-my-sunglasses-are-UV-protected
"The only way to really know is to take then to an optical shop and have then measure the UV transmittance

The UV flashlight method makes a lot of sense but is not accurate.

I bought a bunch of knock-off sunglasses while travelling. I was worried about UV protection and bought a UV light. Some didn't pass the test (see other answers to know what I'm talking about with the flashlight).

Then I took them to an optical shop and had them tested on the two instruments they used. They all tested 100% UV 400 protective. The Irish technician did show me a pair he had that was not protective. They were knock off Ray Ban's with yellow lenses, and they were still a bit better than 50% protective.

Why the UV flashlight doesn't work I don't know. I suspect it's because high frequency light within the visible spectrum (and hence not UV) is still emitted from these flashlights (you know they emit some non-uv light because you can see some of the light they emit), still causes the special UV ink to glow.
"

Spectometer show that galases are 100% protective but test with UV flaslight don't pass,why?

Find out the SPD of the flash, find out the wave length the glass is supposed to protect and at what intensity.

Find out what frequency the ink fluoresces at, if that is specific. Inks dyes and other OBAs tend to be around 400nm or less

The glass may filter out 380-400nm but allow < 380 through.

Use appropriate PPE if you are going to play around with this kit yourself
https://en.wikipedia.org/wiki/Ultraviolet

 

[hutchphd]

It is my understanding that making a window for hard UV is quite difficult (quartz works, but not much else). I rely on this for my UV eye protection and would be interested to know if it is untrue!

 

[Aeronautic Freek]

Find out the SPD of the flash, find out the wave length the glass is supposed to protect and at what intensity.

Find out what frequency the ink fluoresces at, if that is specific. Inks dyes and other OBAs tend to be around 400nm or less

The glass may filter out 380-400nm but allow < 380 through.

Use appropriate PPE if you are going to play around with this kit yourself
https://en.wikipedia.org/wiki/Ultraviolet

flashlight is 390nm, i don't know at which frequency ink lights on money..
but is it strange that some sunglasses pass real test in optic shop with spectometer but they still make ink light at money(which mean that they don't block UV light)..

 

[hutchphd]

Here is what I rely on:

your flashlight is at the edge (of visible) and may show some variation. I believe the claims of special UV lenses are largely puffery.

 

[Aeronautic Freek]

It is my understanding that making a window for hard UV is quite difficult (quartz works, but not much else). I rely on this for my UV eye protection and would be interested to know if it is untrue!

what is "hard " UV?
So you think no one sunglasses can block UV?

 

[pinball1970]

flashlight is 390nm, i don't know at which frequency ink lights on money..
but is it strange that some sunglasses pass real test in optic shop with spectometer but they still make ink light at money(which mean that they don't block UV light)..

Just 390nm? A spectro usually throws a wider range.

 

[Andy Resnick]

It is my understanding that making a window for hard UV is quite difficult (quartz works, but not much else). I rely on this for my UV eye protection and would be interested to know if it is untrue!

Depending on your application, plexiglas (UF-3 or UF-5) may work, as well as polycarbonate (which I think is the window in my cell culture hood as protection against the germicidal bulb)

http://www.plasticgenius.com/2011/05/infrared-and-ultraviolet-transmission.html
https://www.plexiglas.com/export/si...-optical-and-transmission-characteristics.pdf

 

[hutchphd]

If memory serves polycarbonate is quite opaque below 400nm (I don't see anything to contradict this in your attachments). If you know different please advise and point me to reference if possible!.
They do mention and acrylic "G" that has a pretty good window down to 200nm...I was unaware of this material.
For the OP sorry about the Jargon..."hard" UV is shorter wavelength UV say below 250nm or maybe 200nm...

 

[hutchphd]

Depending on your application, plexiglas (UF-3 or UF-5) may work, as well as polycarbonate

Sorry... I misread this earlier. Yes this comports with my understanding about polycarbonate opacity (ignore above).