US 12,405,462 B2
Optical system and image pickup apparatus
Akira Mizuma, Saitama (JP)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Apr. 24, 2023, as Appl. No. 18/305,433.
Claims priority of application No. 2022-073886 (JP), filed on Apr. 27, 2022.
Prior Publication US 2023/0350195 A1, Nov. 2, 2023
Int. Cl. G02B 27/00 (2006.01); G02B 15/15 (2006.01)
CPC G02B 27/0062 (2013.01) [G02B 15/15 (2013.01)] 12 Claims
OG exemplary drawing
 
1. An optical system comprising an optical element having negative refractive power and disposed on at least one of an object side and an image side of an intersection of an optical axis and a pupil paraxial ray,
wherein the optical element is made of a glass material, and
wherein the following inequalities are satisfied:
1.70<Nd<1.85
28.0<νd<39.0
−0.0100<θgF−(0.64168−0.00162×νd)<−0.0040,
where Nd is a refractive index of the optical element for d-line, νd is an Abbe number of the optical element based on the d-line, and θgF is anomalous partial dispersion of the optical element for g-line and F-line.