Canon Patent: RF 15mm f/2 And RF 12mm f/2.8 Lenses

And here is another Canon patent application, for two RF mount lenses.

Canon patent application 023104029 (Japan, 7/28/2023) discusses optical formulas for two fast prime lenses for the RF mount: RF 15mm f/2 and RF 12mm f/2.8.

From the patent literature:

Optical System and Imaging Device Having the Same

A wide-angle lens is provided that is compact and lightweight, and provides a high optical performance in which fluctuations in aberration due to focusing are suppressed while a high photographing magnification can be obtained at the time of photographing at the shortest distance.

Description of the Related Art

In recent years, there has been a demand for wide-angle lenses used in imaging apparatuses that are compact as a whole and that are capable of obtaining a high photographing magnification at the time of photographing at the shortest distance. In addition, there is a demand for a lens having high optical performance in focusing from infinity to the closest object.

In a wide-angle lens, in order to obtain a high photographing magnification at the time of photographing at the shortest distance, it is necessary to increase the amount of movement of the focus lens group, which makes it difficult to reduce the size of the entire lens. In order to reduce the amount of movement of the focus lens group, it is necessary to increase the refractive power of the focus lens group.

[via asobinet]