Canon Patent: 20mm F1.4, 24mm F1.4, and 28mm F1.4 Primes

Here is a new Canon patent application for the nerds out there. Btw, “nerd” is no an insult in my world :-)

Canon patent P2025015010 (japan, published 01/30/2025) discussed optical formulas for a bunch of prime lenses:

• 20mm F1.4
• 24mm F1.4
• 28mm F1.4

From the patent literature:

• An optical system is provided that is compact yet has high optical performance by suppressing aberrations and fluctuations in the angle of view that occur during focusing.
• Description of the Related Art: In recent years, optical systems used in image pickup apparatuses are required to be compact and to perform high-speed focusing.
• In view of this, a system in which a plurality of lens groups move during focusing is known as a compact configuration for suppressing fluctuations in aberrations that occur during focusing while reducing the weight of the lens groups that move during focusing.
• SUMMARY OF THE PRESENT EMBODIMENTS: An object of the present invention is to provide an optical system that is compact and has high optical performance by suppressing aberrations and fluctuations in the angle of view that occur during focusing.

Example 1

• Focal length: 20.63
• F-number: 1.46
• Half angle of view: 42.73
• Image height:
• Overall length: 112.63
• Back focal length: 45.44

Example 2

• Focal length: 28.80
• F-number: 1.46
• Half angle of view: 33.89
• Image height:
• Total length: 119.74
• Back Focus: 14.63

Example 3

• Focal length: 24.72
• F-number: 1.46
• Half angle of view: 37.14
• Image height:
• Overall length: 118.17
• Back Focus: 15.18

More Canon patents are listed here.

[via asobinet]