Egami discovered a new patent filed by Canon in Japan. The new patent describes a Canon EF 600mm f/4 telephoto prime lens. Canon currently has the EF 600mm f/4 IS II USM telephoto prime lens in the lineup. The 600mm f/4 IS II lens introduced in 2010-2011.
According to the patent details as the Egami suggests that the lens will be ready for Tokyo Olympic Games in 2020 and the Rio de Janeiro Olympic Games in 2016.
Canon EF 600mm f/4L IS II USM Lens
Canon Patent For 600mm f/4 Telephoto Prime Lens
- Patent Publication No. 2014-26210
- Publication date 2014.2.6
- Filing date 2012.7.30
- Example 1
- Focal length f = 588mm
- Fno. 4.12
- Angle of view 2ω = 4.22 °
- BF 56.0mm
- Total lens length 374.7mm
- Inner focus
- Example 5
- Focal length f = 588mm
- Fno. 4.12
- Angle of view 2ω = 4.22 °
- BF 55.0mm
- Total lens length 343.5mm
- Inner focus
- Diffraction optical element
- Effect of the glass material
- Fluorite (Fluorite)
- In the long lens fluorite + total length, correction of chromatic aberration is easy
- In short lens fluorite + total length, correction of chromatic aberration is difficult
- Diffractive optical element (DOE)
- Diffractive optical element can be corrected if the chromatic aberration
- Flare caused by light diffraction
- Fluorite (Fluorite)
via EG
