Optical attenuation: photochromic or photodarkening materials for UV

Are there photochromic or photodarkening material that could be deposited on the surface of optical glass to irreversibly provide up to 20dB of attenuation at 1310nm once irradiated by UV light? The attenuation is to stay after the UV excitation is removed.

But with no attenuation beforehand?

Sounds like you are after a Photographic Emulsion as used on camera film.
If you don't mind a post-exposure wash thru developer, that could be direction to look.

A Google search
(https://www.google.com/search?hl=en&q=uv+photographics )

found: https://uvphotographics.com/

Kodak, the camera and film company, makes a variety of chemicals used in the photo-lithography of Integrated Circuit (IC) manufacturing.

If a post-exposure wash is not available, there are many materials that are physically damaged by heavy UV exposure, which could be another search area; although many of them tend to disintegrate from exposure. (Sorry, I don't recall any details of these.)

Cheers,
Tom

Thank you great suggestions!

berkeman said:

But with no attenuation beforehand?

Or minimal attenuation before

What sensitivity range do you want.? UV optically degrades almost everything over time! There are many photochromic dyes and paints as well as UV cure epoxies etc.
To your exact question there is a thing called google:
https://www.nvisioncenters.com/glasses/photochromic-transition-lenses/#:~:text=While film exposure is made,the absence of ultraviolet light.
https://www.mentalfloss.com/article/75665/how-do-transition-lenses-work

Additionally, glass is pretty opaque to UV to begin with. And 1310 nm is in the infrared,