A new Canon patent for two lenses with inner zoom mechanism. Canon patent application 2024079936 (Japan, published 6/13/2024) discusses optical formulas for two (likely RF-mount) lenses with an inner zoom, i.e. they do not extend or retract when zooming:

• 5-60mm f/2.8
• 22-80mm f/2.8

From the patent literature:

• A zoom lens that has a high zoom ratio and a large aperture ratio, yet is compact, lightweight, and provides high image quality, and that allows high-speed zoom operation.
• Background Art
  There is a demand for a zoom lens that is compact and lightweight throughout its entire system, has excellent correction of chromatic aberration and other aberrations, and has high optical performance. There is also 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. There is also a demand for a zoom lens that allows high-speed zoom operation.
• However, the zoom lens described in Patent Document 1 has a tendency to have a large lens diameter due to its small F-number, and the large front lens diameter leads to an increase in size and weight. In addition, if the refractive power of the second lens group is increased in order to reduce the front lens diameter, it becomes difficult to achieve high image quality.
• The present invention provides a zoom lens that has a high zoom ratio and a large aperture ratio, yet is compact, lightweight, and provides high image quality, and is capable of high-speed zoom operation.

Example 1

• Focal length: 24.72-101.86
• F-number: 2.90
• Half angle of view: 41.19-11.99
• Total length: 212.40
• Back Focus: 11.98-21.74

Example 2

• Focal length: 15.45-58.20
• F-number: 2.90
• Half angle of view: 41.5-13.2
• Image height:
• Overall length: 144.55
• Back focal length: 13.62

Example 3

• Focal length: 24.71-116.38
• F-number: 2.90
• Half angle of view: 41.3-10.0
• Image height:
• Overall length: 231.23
• Back focus: 11.38-23.01

Example 4

• Focal length: 22.60-82.99
• F-number: 2.90
• Half angle of view: 44.3-14.1
• Image height:
• Overall length: 216.25
• Back Focus: 11.83-22.33

More Canon patents are listed here.

[via asobinet]

Here is a new Canon patent application. Does the patent refer to the Canon RF 24-70mm f/2.8L IS?

Canon patent application 2024078721 (Japan, published 6/11/2024) discusses optical formulas for a 28-70mm f/2.8 IS lens.

From the patent literature:

• The present invention provides a compact zoom lens that has a high zoom ratio, good optical performance over the entire zoom range from the wide-angle end to the telephoto end, and has a large aperture and an image stabilization mechanism.
• Background Technology
  In recent years, zoom lenses used in imaging devices such as digital cameras using solid-state imaging elements and silver halide film cameras are required to be small in size, have high optical performance, have a large aperture, and be equipped with an image stabilization mechanism (anti-vibration mechanism).
• In order to achieve this, it is important to appropriately set the zoom type of the zoom lens and the lens group that moves during zooming.
• The present invention provides a compact zoom lens that has a high zoom ratio and good optical performance over the entire zoom range from the wide-angle end to the telephoto end, has a large aperture, and has an image stabilization mechanism.

More Canon patents are listed here.

[via asobinet]

A new Canon patent for two lenses for mirrorless cameras, one for APS-C and the other for full-frame. Both have inner zoom mechanism.

Canon patent application 2024076793 (Japan, published 6/6/2024) discusses optical formulas for two lenses with inner zoom:

• 12-30mm f4-6.3 IS (APS-C)
• 20-40mm f/4 IS (full-frame)

From the patent literature:

• An object of the present invention is to provide a negative lead type wide-angle zoom lens that is small and lightweight and has high optical performance over the entire zoom range.
• BACKGROUND ART In recent years, it has been desired that an imaging optical system used in an imaging device be a small zoom lens that has a wide angle of view and has high optical performance over the entire zoom range.
• Patent Document 1 discloses a negative lead type wide-angle zoom lens in which a first lens group with a negative refractive power is disposed closest to the object side as a zoom lens whose entire system is small and whose angle of view can be easily widened. Proposed.
• The negative lead type wide-angle zoom lens proposed in Patent Document 1 widens the angle of view by moving the first lens group with negative refractive power when zooming from the wide-angle end to the telephoto end. It achieves high optical performance.
• However, the configuration in which the first lens group, which is large and has a large mass, is moved, as in the wide-angle zoom lens described in Patent Document 1, complicates the movement mechanism and is disadvantageous from the viewpoint of miniaturization and weight reduction.
• The present invention provides a negative lead type wide-angle zoom lens that is compact and lightweight, yet has high optical performance over the entire zoom range.

Example 1

• Focal length: 12.42-29.07
• F value: 4.10-6.40
• Half angle of view: 47.72-25.17
• Image height: 11.37-13.66
• Total length: 82.97
• Back focus: 12.29

Example 2

• Focal length: 14.40-29.10
• F value: 4.10-6.29
• Half angle of view: 43.40-25.14
• Image height: 11.46-13.17
• Total length: 75.06
• Back focus: 11.78

Example 3

• Focal length: 20.60-39.00
• F value: 4.10
• Half angle of view: 46.40-29.01
• Image height: 17.94-20.74
• Total length: 97.01
• Back focus: 12.68

Example 4

• Focal length: 20.60-48.50
• F value: 4.10-5.88
• Half angle of view: 46.40-24.04
• Image height: 18.22-21.64
• Total length: 106.52
• Back focus: 19.41

More Canon patents are listed here.

[via asobinet]

Here is a new Canon patent application, one for a RF-S and one for a RF lens.

Canon patent application 2024072459 (Japan, 5/28/2024) discusses optical formulas for two RF-mount lenses:

• RF-S 14-30mm f/4-6.3 [for APS-C imaging sensors]
• RF 20-50mm f/4-5.6

From the patent literature:

• The present invention provides a zoom lens that is both compact and lightweight and has high image quality, has a short focal length at the wide-angle end, is easy to manufacture, is inexpensive, and allows high-speed zoom operations.
• BACKGROUND ART
  Zoom lenses used in imaging devices are required to be small and lightweight, have various aberrations including chromatic aberration well corrected, and have high optical performance. Additionally, there is a demand for a zoom lens that has a short focal length at the wide-angle end, is easy to manufacture, and is inexpensive. Furthermore, there is a demand for a zoom lens that allows high-speed zoom operations.
• In order to provide such a zoom lens, the arrangement of the aspherical lens is important. If an aspherical lens is placed in the second lens group, which is placed adjacent to the image side of the first lens group closest to the object and has a high axial ray height, the required precision of the aspherical lens will be high, making it difficult to manufacture. As the power increases, it becomes difficult to provide an inexpensive zoom lens. On the other hand, if an aspherical lens is not disposed in the second lens group, it will be difficult to suppress aberrations generated in the second lens group, making it difficult to achieve high image quality. Furthermore, in order to provide a zoom lens that can realize high-speed zoom operations, it is effective to fix the first lens group with a large lens diameter and move only the lens group with a small lens diameter. However, by fixing the first lens group closest to the object, aberration correction deteriorates and it becomes difficult to achieve high image quality.
• Patent Document 1 describes a compact and lightweight zoom lens that includes a first lens group with negative refractive power, a second lens group with positive refractive power, and a second lens group with negative refractive power, which are arranged in order from the object side. A zoom lens has been proposed that includes a third lens group and a fourth lens group with positive refractive power. The first lens group is fixed relative to the image plane during zooming.
• The present invention provides a zoom lens that is both compact and lightweight and has high image quality, has a short focal length at the wide-angle end, is easy and inexpensive to manufacture, and allows high-speed zoom operations.

Example 1

• Focal length: 14.40-29.10
• F value: 4.10-6.40
• Half angle of view: 43.4-25.1
• Total length: 75.06
• Back focus: 11.78

Example 3

• Focal length: 12.40-29.10
• F value: 4.10-6.40
• Half angle of view: 47.9-25.2
• Total length: 82.67-82.67
• Back focus: 11.71

Example 3

• Focal length: 20.60-48.50
• F value: 4.10-5.88
• Half angle of view: 46.4-24.2
• Total length: 106.52-106.52
• Back focus: 19.41

More Canon patents are listed here.

[via asobinet]