Help ID Fitted Case With Acrylic Prism Things

Hope I'm in the right forum. Anybody know what this is? The 17" long fitted case has an array of numbered acrylic (?) prisms/lenses (?) all clear color save for a thin red one at the far left. I've struck out in my searching. Thanks.

 

We had a set similar to that in physics lab in high school. They weren't curved though.

 

Is there a Polarizing filter in there somewhere?

 

Optician's lenses?

 

The numbers might correlate with degree of angle.
Wonder if is has to do with light refraction measurements. Have no idea why you would need to know something like that.

 

If you want to do an experiment put light behind each and look at them through Polarizing sunglasses.

 

My sister-in-law suggested they are a set of corrective heels using for fitting orthopedic shoes for people with a deviated ankle. The podiatrist would have people stand sock-footed on sample heels until they found the best correction, then order shoes made with that angle heel. They would go from very slight correction (small angle) to extreme correction (biggest angles).

 

10 toes up for that.

 

I like it, I accumulate such things. Let me know if you decide to sell it.

 

They are ophthalmic prisms used by optometrist/ophthalmologist for testing vision.

http://lpoproducts.com/luneauprismbarsethor-vert.aspx

 

Similar case anyway.

 

Nothing but crickets.

 

Thanks for all for the responses. It appears to be a set of ophthalmic prisms as noted by Hollyblue. I had a feeling the board would get to the bottom of this one. Appreciate it.

 

chrip, chirp, chirp ...

 

Hmmmmmmm....
Still......

 

But there's no variation allowed for potential heel/ankle pronation IF they did have anything to do with feet????

 

feet would slide down......
do feet have eyes..?
maybe they are for potato's ........

 

Well...there are egg scales so maybe potato sizers?

 

Spud...foot.... 4 letters.....