Magnifying Visors

Where can I find information on Optics?

I am looking for some information on some optics I was given. The box contains a metal slide holder with a built in probe. It also contains a tube with a lens marked EDSCORP on one side and 10 0.25 JAPAN. on the other. There are also two other lenses that are unmarked. I would like any information on these optics or help in finding information. They came from an old science classroom and I have no idea on how old they are. Everything is in excellent condition. There is a little tarnish on the slide holder, and the two smaller lenses show signs of use, but the tube and larger lens very clean.

Public Comments

1. Go and look up in encyclopedia for answer and/or ask the person that you got from.
2. As you have two unmarked lenses you'll never find out about them from a book/manufacturers charts/the web. You'll need to test them yourself. Fortunately it's very easy to test them to find out their properties. Focus is easy shine light through and see where it converges. More accurate testing of this can be done with a laser and observing speckle patterns. Once you know the focus measure the curvature and from that you can calculate the refractive index of the lens.