Canon RF 28-70mm f/2 L USM:
B&H Photo / Amazon / Adorama
Canon RF 24-70mm f/2.8 L IS USM:
B&H Photo / Amazon / Adorama
Patents were found for Canon 14-20mm f/2 and Canon 14-24mm f/2.8 lenses. These lenses will fit well with Canon’s current RF lineup of lenses.
overview
- [Publication number] P2024071267
- [Release date] 2024-05-24
- [Name of invention] Zoom lens, and imaging device and imaging system having the same
- [Applicant]
[Identification number] 000001007
[Name or company name] Canon Inc. - A zoom lens that is compact yet has high optical performance and a short close-up focus distance is provided.
- [Background Art]
[0002]
Wide-angle zoom lenses, which have a wide angle of view, are suitable for landscape photography and other purposes that take advantage of the wide angle of view. However, while wide-angle zoom lenses are relatively easy to use for close-up photography compared to telephoto lenses, they have the characteristic that the maximum shooting magnification is low due to their wide angle of view. In the case of large-aperture wide-angle zoom lenses, the lens diameter and overall length tend to be large, and if the focus movement is increased to shorten the closest distance, the lens becomes even larger, and the optical performance at infinity, which is important for landscape photography, tends to deteriorate. - [0003]
A typical wide-angle zoom lens is a so-called retrofocus type consisting of a negative front group and a positive rear group, and employs a floating method in which multiple lens groups are moved during focusing in order to achieve high optical performance from infinity to close distances. - [0004]
Patent document 1 discloses a zoom lens consisting of a negative first lens group, a positive second lens group, a negative third lens group, and a positive fourth lens group arranged in this order from the object side. In the zoom lens described in Patent document 1, the second lens group and the third lens group are moved toward the image side during focusing, thereby improving the optical performance from infinity to close distances. - [0006]
However, in order to further improve the magnification of the zoom lens described in Patent Document 1, it is necessary to increase the amount of movement of the focus lens group and strengthen the refractive power of the focus lens group, which increases the overall lens length and is likely to cause problems such as a decrease in imaging performance near infinity. - The present
invention provides a zoom lens that is compact, has high optical performance, and has a short close-up distance.
Example 1
- Focal length: 12.29-23.80
- F-number: 2.93
- Half angle of view: 60.39-42.27
- Image height: 21.64
- Overall length: 138.05-134.83
- Back focus: 13.86-19.48
Example 2
- Focal length: 11.30-23.80
- F-number: 2.93-4.09
- Half angle of view: 62.42-42.27
- Image height: 21.64
- Overall length: 138.04-136.22
- Back Focus: 13.87-22.14
Example 3
- Focal length: 14.30-21.50
- F-number: 2.06
- Half angle of view: 56.54-45.18
- Image height: 21.64
- Overall length: 148.04-139.46
- Back focus: 13.87-20.30
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