Canon filed a new patent in Japan. The new patent describes the EF 600mm f/4 DO IS lens designed for Canon DSLRs with full-frame image sensors.
A similar patent with diffractive optical (DO) lens can be seen here. As EF 400mm f/4 DO IS II telephoto prime lens became official and currently priced for $6,899.95 at Amazon.
Canon lenses which feature the diffractive optical (DO) are smaller and lighter compared to the same focal length lenses but the price becomes generally higher when the lenses have optical formual for DO.
The EF 400mm f/4 DO IS II was announced late last year
Canon EF 600mm f/4 DO IS USM Lens Patent
- Patent Publication No. 2015-11171
- Published 2015.1.19
- Filing date 2013.6.28
- Example 2
- Focal length 588.30mm
- Fno. 4.12
- Angle of view 2.11 °
- Image height 21.64mm
- The total lens length 397.80mm
- BF 2.02mm
- Positive ShiboTadashi
- Inner focus
- Vibration control
via: EG
