Canon Patent: 20mm f/1.8, 28mm f/1.8 And 24mm f/1.8 With Backlight Control

A new Canon patent for RF mount lenses: 20mm f/1.8, 28mm f/1.8 and 24mm f/1.8.

Canon patent application 2022122047 (Japan) discusses optical formulas for three RF mount lenses with backlight control. From the patent literature:

An object of the present invention is to provide an optical system that is less affected by unnecessary light and has high optical performance.

Description of the Related Art

There is a demand for further improvement in performance and miniaturization of photographing optical systems. [0005]When trying to improve the performance of an optical system, the number of lenses constituting the optical system increases. On the other hand, if an attempt is made to reduce the size of the optical system by shortening its overall length, the distance between the lenses constituting the optical system and the distance between the optical system and the imaging surface will be shortened. As a result, unnecessary light (ghost) caused by reflection of light on each lens surface easily reaches the imaging surface.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide an optical system that is less affected by unnecessary light and has high optical performance.

Example 1

• Focal length: 28.60
• F-value: 1.85
• Half angle of view: 37,1
• Image height: 20.15
• Total length: 81.00
• Back focus: 13.20

Example 2

• Focal length: 20.60
• F-value: 1.85
• Half angle of view: 46.4
• Image height: 18.71
• Overall length: 84.87
• Back focus: 11.00

Example 3

• Focal length: 24,72
• F-value: 1.85
• Half angle of view: 41.2
• Image height: 19.34
• Total length: 81.00
• Back focus: 11.00

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]