Thoriated Lenses

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I’ve recently been reading about how thorium was once added to camera lenses. Does anyone know if Vivitar was among those adding them? I’m quite concerned about it, but I tend to be panicked about every little thing. Also, is there anything to suggest that it was ever added to binoculars? I have an old pair of Sears binoculars, but they have a bluish-tint to the lenses it would seem. Thoriated lenses are said to have a reddish tint. By the way, is this the only thing that would ever tint it red?

Thank you! I hope it wasn’t wrong to place this in this category by the way.

I doubt that the radiation dose from any commercial lens is a significant risk. Industrial workers carry small dose badges that are essentially nothing more than unexposed camera film, which darkens on exposure to radiation. Any radioactive lens would fog the camera film.

More importantly, the colour reflected from most lenses is produced by the anti-reflective and scratch-resistant coatings on the exterior and is not related to the lens chemistry.

Health Physics Society comment: http://hps.org/publicinformation/ate/q1356.html

Thank you for the response. Actually, I was thinking of the fogging aspect myself, and read up on it. Apparently, if you left a thoriated lens in a camera for weeks, it may actually fog the film. That kind of proves that mine wasn’t an effected model, since I left it in a camera for months once will no ill effects on the exposures. I also found a listing of all the lenses that were known to contain Thorium, and it was nowhere near any of them.

Sadly enough, I had to get rid of it anyways today because it was worn out, for totally unrelated reasons.

I’m glad to know it wasn’t a thoriated model though!

Hey, does this mean that thoriated binoculars really just don’t exist?

Thanks again.