| O | Object position | f' (=H'F') | Focal length |
| O' | Image position | k (=f'/dEP) | f-number (indicated as "f/k") |
| H | Front principal plane | i (=HH') | Principal point separation |
| H' | Back principal plane | sF (=SF) | Front focal length |
| F | Front focal plane | s'F (=S'F') | Back focal length |
| F' | Back focal plane | sEP (=SP) | Entrance pupil position |
| P | Entrance pupil plane | s'AP (=S'P') | Exit pupil position |
| P' | Exit pupil plane | d (=SS') | Overall optical length |
| S | Vertex of first lens surface | dEP | Entrance pupil diameter |
| S' | Vertex of last lens surface | dAP | Exit pupil diameter |
| | ß'P (=dAP/dEP) | Pupil magnification |