Egami has discovered a new patent filed by Canon. The new patent describes a dual motor autofocus for STM lenses which could be the next step in STM lens technology.
The patent image shows a leaf shutter mechanism. The AF in the patent is driven by 2 motors, the main STM and an auxiliary DCM motor. EF Leaf shutter lens that will allow a true 1/1000s are on the drawing board.
See the patent details below.
Canon Patent For Super Fast Auto-Focus Using 2 Motors
- Patent Publication No. 2014-164106
- Published Date 2014.9.8
- Filing date 2013.2.25
- Example 1
- Moving the aperture one two motors
- Main motor STM
- Auxiliary motor DCM
- And then rotate the first auxiliary motor, to assist the acceleration of the main motor