![](https://coimages.sciencemuseumgroup.org.uk/375/636/large_thumbnail_1928_0920__0001_.jpg)
Medium field slide from EROS IV optical transfer function measuring system for lens testing
- maker:
- R and J Beck
Medium field slide from EROS IV optical transfer function measuring system for lens testing, made by R & J Beck Ltd. in about 1966
Medium field slide from EROS IV optical transfer function measuring system for lens testing, made by R & J Beck Ltd. in about 1966