Back to results
US 2025/0076673 A1Published application
Optical system and image pickup apparatus
AssigneeCanon Kabushiki Kaisha
InventorKentaro MORI
Life of this patent
Estimating the term…
Abstract
An optical system includes, in order from an object side to an image side, a diffractive optical element having positive refractive power, and a diffractive surface with a controlled wavelength dispersion characteristic, and a lens having negative refractive power. A predetermined inequality is satisfied.
Claims18
An optical system comprising, in order from an object side to an image side:
- a diffractive optical element having positive refractive power, and a diffractive surface with a controlled wavelength dispersion characteristic;
- and
- a lens having negative refractive power,
- wherein where ν0 is an Abbe number of the diffractive surface, a reference wavelength is d-line, primary dispersion is F-line and C-line, Ψ(λd), Ψ(λF), and Ψ(λC) are optical path difference functions for the d-line, the F-line, and the C-line, respectively, P(λd), P(λF), and P(λC) are optical path difference dispersions of a surface for the d-line, the F-line, and the C-line, respectively, the following equation is satisfied:
- 1
- v
- o
- ≡
- ψ
-
- (
- λ
- F
- )
- -
- ψ
-
- (
- λ
- C
- )
- ψ
-
- (
- λ
- d
- )
- =
- λ
- F
-
- P
-
- (
- λ
- F
- )
- -
- λ
- C
-
- P
-
- (
- λ
- C
- )
- λ
- d
-
- P
-
- (
- λ
- d
- )
- ,
- and the following inequality is satisfied:
- -
- 0
- .
- 2
- <
- 1
- /
- v
- 0
- <
- 0
- .
- 2
- .
69 more elements
An optical system comprising, in order from an object side to an image side:
- a metalens having positive refractive power, and a metasurface with a controlled wavelength dispersion characteristic;
- and
- a lens having negative refractive power,
- wherein where vo is an Abbe number of the metasurface, a reference wavelength is d-line, primary dispersion is F-line and C-line, Ψ(λd), Ψ(λF), and Ψ(λC) are optical path difference functions for the d-line, the F-line, and the C-line, respectively, P(λd), P(λF), and P(λC) are optical path difference dispersions of a surface for the d-line, the F-line, and the C-line, respectively, the following equation is satisfied:
- 1
- v
- o
- ≡
- ψ
-
- (
- λ
- F
- )
- -
- ψ
-
- (
- λ
- C
- )
- ψ
-
- (
- λ
- d
- )
- =
- λ
- F
-
- P
-
- (
- λ
- F
- )
- -
- λ
- C
-
- P
-
- (
- λ
- C
- )
- λ
- d
-
- P
-
- (
- λ
- d
- )
- ,
- 1
- and the following inequality is satisfied:
- -
- 0
- .
- 2
- <
- 1
- /
- v
- 0
- <
- 0
- .
- 2
- .
70 more elements
Dependencies are inferred from the claim text.