Anyone have any idea what this (tool?) is?

[ramses]

I don't. My dad found them when going through some of my grandfather's stuff.

[jackssmirkingrevenge]

have you tried googling the german lettering?

[Gaderelguitarist]

The ticking leads me to believe that it is some sort of caliper. But then what are the triangles for?

[Technician1002]

It looks like some sort of optical bench tool. Are the triangles a corner prism by any chance? I can't tell from the photos. They may be used for measuring lenses and are used to measure the focal length.

The prisms appear to have a center alignment mark in red.

Another possibility is a tool for an optometrist. You look into each corner prism and align the red marks to the center of your pupils. As you look past the red marks the reflectors will show you your other eye in the distance past the second mark. When both eyes see both red marks in line the distance between the eyes is shown on the scale. This would be used for placing the center of eyeglass lenses over the center of the eyes when making glasses. This is probably my best guess. It is an old optometrist tool.

[jrrdw]

What did your grandfather do for a living?

[nature-boy]

As I saw the pictures, I was about to say the same what i read seconds later in Techs post. I'm pretty sure it is exactly that.
And the fact that rodenstock is a german producer of glasses/frames, supports that hypothesis.

[ramses]

He was tool and die as far as I know. The corner things are prisms (or mirrors with protective plastic pieces. Kind of a pentamirror vs pentaprism thing.

I didn't realize the last picture was out of focus.

Tech, I half suspected it was something to do with eye spacing, but I couldn't get anything meaningful out of it. Thanks for the help.