Canon Patent: RF 24-300mm f/2.8-5.6 IS, RF 24-240mm f/2-5.6 IS And RF 40-350mm f/2.8-5.6 IS

And another Canon patent for lenses for the RF mount.

Canon patent application 2023104137 (Japan, published 7/28/2023) discusses optical formulas for three zoom lenses for the RF mount:

• RF 24-300mm f/2.8-5.6 IS
• RF 24-240mm f/2-5.6 IS
• RF 40-350mm f/2.8-5.6 IS

From the patent literature:

A zoom lens, an imaging device having the same, and an imaging system

To provide a zoom lens that is compact as a whole, has a high zoom ratio, and has high optical performance over the entire zoom range.

BACKGROUND ART

In recent years, there has been a demand for a zoom lens used in an imaging apparatus having an imaging device to have a compact overall system, a high zoom ratio, and high resolution (high optical performance). . In particular, zoom lenses are required to have high optical performance with substantially uniform resolving power from the center of the screen to the periphery of the screen.

However, in the zoom lenses disclosed in Patent Documents 1 and 2, since the relationship between the refractive powers of the lens groups is not appropriate, the lens size increases when the zoom ratio is increased, and astigmatism at the wide-angle end and coma at the telephoto end gets worse.

The present invention provides a zoom lens that is compact overall, has a high zoom ratio, and has high optical performance over the entire zoom range.

More Canon patents are listed here.

[via asobinet]