Canon Patent: RF-S 10-14mm F3.5-4 Lens For APS-C

After a long time, here is a new Canon patent application.

Canon patent application 2023066202 (Japan, published 5/15/2023) discusses optical formulas for a RF-S 10-14mm F3.5-4 lens, i.e. a lens for the RF-mount and APS-C imaging sensors.

From the patent literature:

An object of the present invention is to provide a zoom lens capable of reducing the occurrence of ghost while having high optical performance.

BACKGROUND OF THE INVENTION

Field of the Invention The present invention relates to zoom lenses and the like, and is suitable for imaging devices such as digital video cameras, digital still cameras, broadcast cameras, and silver halide film cameras.
Description of the Related Art

Wide-angle lenses are widely used for landscape photography, astrophotography, and the like. A wide-angle lens is required to achieve high optical performance while widening the angle of view.
In the zoom lens disclosed in Patent Document 1, since the opening angle of the first lens is large, unwanted light reflected obliquely from the lens surface of the second lens on the object side becomes an image of the first lens. It was sometimes reflected on the lens surface on the side and reached the image plane. When such unnecessary light reaches the image plane, it is undesirable because it causes a ghost image on the photograph.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide a zoom lens capable of reducing the occurrence of ghost while having high optical performance.

Example 1

• Focal Length: 15.45-29.15
• F-value: 4.60-6.32
• Half angle of view: 49.36-36.19
• Image height: 18.00-21.33
• Overall length: 115.26-107.01
• Back focus: 13.50

Example 2

• Focal length: 9.97-14.64
• F-value: 3.50-4.23
• Half angle of view: 49.63-41.54
• Image height: 11.72-12.97
• Overall length: 72.73-71.78
• Back focus: 10.06-14.3

More Canon patent applications are listed here. Some particularly interesting patent applications we think might get into production are these:

• RF 16-28mm lens with either f/2.8, f/2.8-4, or f/4
• Automatic shutter silencing based on subject and distance
• A bunch of prime lenses for the RF mount
• An improved Electronic Viewfinder
• Patent application for RF 50mm F1.4 and an RF 35mm f/1.4 lenses
• A zoom lens that might be for an EOS R with APS-C sensor
• A smaller IBIS unit.
• A cooling adapter for the RF mount (R5 overheating?)
• A bunch of macro lenses for the RF mount.
• A 8mm f/4 circular fisheye lens for the Canon EOS R system
• A battery grip that works with differently siszed cameras
• A 100-400mm f/5.5-7.1 lens for APS-C cameras. EOS M or DSLR?
• RF 17-70mm lens for EOS R system
• IBIS coming to the EOS M and PowerShot lineup?
• Patent Application: mirrorless camera with large display and virtual control wheel
• Patent Application: IBIS and Lens IS Working Together
• Patent application for high speed mirror movement and control
• Patent application for an RF 14-28mm f/2 lens
• Patent application for an RF 50mm f/1.8 lens
• Patent application for a smart lens cap
• Patent application for celestial auto-focus
• Patent application describing a Pop-Up Flash With LED
• Patent application describing the optical formula for a RF 70-300mm F/4-5.6 IS lens for EOS R systems
• Patent application describing how to improve burst rate by compressing raw files
• Patent application describing a new way to review photos from a sequential shot
• Patent application that describes technology to improve wireless communication while reducing power consumption
• Patent application to spot and reduce moire artefacts in image data
• Patent application for weather sealed lens adapter
• Patent application for AI powered predictive camera control system
• Patent application for 18-55mm kit lens with LCD display
• Patent application to reduce noise in image files

[via asobinet]