15-60mm Archives - CanonWatch

Canon Patent: RF 24-105mm f/2.8 Z And RF 15-60mm f/2.8 Z Lenses

A new Canon patent application for two lenses featuring Canon’s new silent USM zoom technology (hence the “Z”).

Canon patent application 2024025100 (Japan, published 02/26/2024) discusses optical formulas and methods for two zoom lenses:

From the patent literature:

The present invention provides a zoom lens that is compact, has a high zoom ratio, and a large aperture ratio, yet achieves high image quality and high-speed zoom operation.
BACKGROUND ART: As a zoom lens used in an imaging device, there is a demand for a zoom lens that is small and lightweight, and has high optical performance that can satisfactorily correct various aberrations such as chromatic aberration. Additionally, there is a demand for a zoom lens that has a short focal length at the wide-angle end, a large zoom ratio, a small F number, a large aperture ratio, and is easy to manufacture. Additionally, there is a demand for a zoom lens that allows high-speed zoom operations. Patent Document 1 discloses a zoom lens that includes, in order from the object side to the image side, a lens group with positive refractive power, a lens group with negative refractive power, and a rear group having a plurality of lens groups. .
Although the zoom lens disclosed in Patent Document 1 is small, has a high zoom ratio, and a large aperture ratio, it is difficult to achieve high image quality and high-speed zoom operation.
Accordingly, an object of the present invention is to provide a zoom lens that is compact, has a high zoom ratio, and a large aperture ratio, yet achieves high image quality and high-speed zoom operation.

Example 1

Example 2