A Patent has been found for a new Canon 50mm f/1.2 lens. You can check out the patent below:
overview
- [Publication number] P2025118483
- [Release date] 2025-08-13
- [Title of invention] Optical system and imaging device
- [Application date] 2024-08-01
- [Applicant]
[Identification number] 000001007
[Name] Canon Inc. - An optical system is provided that is large in diameter, yet compact, has high optical performance, and is capable of high-speed focusing.
- [Background Art]
[0002]
Patent Document 1 discloses an optical system that is large-aperture yet compact, has high optical performance, and is capable of focusing, and is composed of, arranged in order from the object side to the image side, a front group having positive refractive power, an aperture stop, and a rear group having positive refractive power. In this optical system, the front group moves during focusing. - [0004]
In large-aperture optical systems, it tends to be difficult to correct various aberrations. Furthermore, if the focus lens group is made lighter to achieve faster autofocusing, it becomes difficult to suppress aberration fluctuations during focusing. The optical system of Patent Document 1 corrects various aberrations by using multiple aspherical lenses, but the correction of sagittal coma flare is insufficient. Furthermore, since the front group, which has a large aperture and a large number of lenses, must be moved during focusing, it is difficult to speed up autofocusing. - The present
invention provides an optical system that is large in diameter, yet small in size, has high optical performance, and is capable of high-speed focusing, and an imaging apparatus equipped with the same. - In
addition, the rear group Lr includes at least one aspherical lens La (Lb) having an aspherical surface with a pole point at a position away from the optical axis (hereinafter referred to as the peripheral portion). This aspherical lens provides a difference in refractive power to the central light beam and the peripheral light beam, thereby effectively correcting sagittal coma flare.
Example 1
- Focal length: 48.50
- F-number: 1.25
- Half angle of view: 24.04
- Image height: 21.64
- Total length: 113.00
- Back focal length: 11.92
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