LOMO (CKBK) Experimental Projection lens OKP4-75-1

I was unable to find this lens in my reference books, unfortunately.

It is projection lens for sure. Focal length is 75 mm. High speed - f/1.6. Experimental sample made at CKBK in 1968.

They decided that there is no need to use best glass for experiments, and installed scratched second lens - see the picture. This will not affect image quality too much.

The lens is heavy - 3500 g.

Front diameter is 104 mm.

Rear diameter is 68 mm.

Length is 250 mm.