Camera lens mount
2014-02-11 17:29:43


The openness of following case has been allowed by our clients with exception of key parameters, which is only 90% of complete design process.
I. Application
For old leica camera telephoto type (focal length more than 50 mm)
II. Requirements
Interface: L39 screw (flange distance 28.8 mm)
EFL: fixed focus 63 mm
Minimum object distance: 0.7 m
Lens maximum diameter: less than 47 mm
Lens front thread diameter: 39 mm
Lens cone material: hard aluminum, stainless steel
Focusing mode: external
Viewing angle: 20 degrees
Variable aperture available
Maximum aperture (f / 2.2) lens cone without light blocking
Pay attention to eliminate parasitic light in lens cone 
III. Features
This optical system has vignettingin when there islargest aperture, so maximum mechanical aperture reach 23 is enough. Lens fixing is pressing ring, so requirements on  processing is relatively low and easy to adjust. Due to leica is paraxial focus, so it needs linkage parts. The standard lens of leica amount to 53.3 mm, so the displacement of linkage and focusing part can be calculated. Design of Linkage part and focusing part is one of design difficulties for such lens.
IV. Results