Canon continues to file tons of patents for new mirrorless lenses.
overview
- [Publication number] P2024103311
- [Release date] 2024-08-01
- [Title of invention] Optical system and imaging device
- [Application date] 2023-01-20
- [Applicant]
[Identification number] 000001007
[Name or company name] Canon Inc. - An optical system that is compact overall and has a small and lightweight focus lens group is provided.
- [Background Art]
[0002]
In optical systems called macro lenses (microlenses) used for close-up photography, a floating method in which two or more lens groups are moved during focusing is often adopted in order to suppress aberration fluctuations during focusing. Another focusing method is the inner focus method in which focusing is performed by moving an intermediate group of the optical system. - [0005]
In order to reduce the size and weight of the lens group used for focusing, it is important not only to adopt the inner focus method but also to appropriately configure the lens group arranged on the object side of the focus lens group and the lens group used for focusing. In addition, in order to reduce the size of the optical system and reduce aberration fluctuations during focusing, it is important to appropriately set the arrangement, refractive power, and movement amount of the lens group arranged on the object side of the focus lens group and the focus lens group. In the optical systems of Patent Documents 1 and 2, none of these are appropriately set, and the size of the optical system and the size and weight of the focus lens group are not sufficiently reduced. - The present
invention provides an optical system which is small overall, has a small and lightweight focus lens group, and has high optical performance over the entire object distance, and an image pickup apparatus equipped with the same.
Example 1
- Focal length: 179.96
- F-number: 3.60
- Half angle of view: 6.86
- Image height: 21.64
- Overall length: 171.15
- Back focal length: 26.35
- Magnification: -1.0
Example 2
- Focal length: 299.99
- F-number: 4.12
- Half angle of view: 4.12
- Image height: 21.64
- Overall length: 210.00
- Back focal length: 38.69
- Magnification: -1.0
Example 3
- Focal length: 188.87
- F-number: 4.00
- Half angle of view: 6.53
- Image height: 21.64
- Total length: 188.87
- Back focal length: 32.67
- Magnification: -2.0
Example 5
- Focal length: 235.51
- F-number: 4.12
- Half angle of view: 5.25
- Image height: 21.64
- Total length: 202.50
- Back focal length: 66.52
- Magnification: -1.0
Example 9
- Focal length: 110.03
- F-number: 4.12
- Half angle of view: 11.12
- Image height: 21.64
- Overall length: 110.03
- Back focal length: 17.52
- Magnification: -1.0
via asobinet