Optical system and image capturing apparatus including the same
AssigneeCanon Kabushiki Kaisha
InventorYUICHI GYODA
Life of this patent
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Abstract
An optical system includes, in order from an object side to an image side, a first lens having positive refractive power, a second lens having negative refractive power disposed adjacent to the first lens on an image side, and a folded optical element disposed adjacent to the second lens on the image side, wherein certain inequalities are satisfied where NdG1 represents a refractive index of a material of the first lens for a d-line, and νdG1 represents an Abbe number of the material of the first lens for the d-line.
Claims25
An optical system comprising, in order from an object side to an image side:
- a first lens having positive refractive power;
- a second lens having negative refractive power disposed adjacent to the first lens on an image side;
- and
- a folded optical element disposed adjacent to the second lens on the image side,
- wherein the following inequalities are satisfied:
- 1.3
- <
- NdG
-
- 1
- <
- 1.6
- ;
- and
- 73.
- <
- vdG
-
- 1
- <
- 120.
- ,
- where NdG1 represents a refractive index of a material of the first lens for a d-line, and νdG1 represents an Abbe number of the material of the first lens for the d-line.
An image capturing apparatus comprising:
- an optical system;
- and
- an image sensor configured to receive an image formed by the optical system,
- wherein the optical system includes, in order from an object side to an image side:
- a first lens having positive refractive power;
- a second lens having negative refractive power disposed adjacent to the first lens on an image side;
- and
- a folded optical element disposed adjacent to the second lens on the image side, and
- wherein the following inequalities are satisfied:
- 1.3
- <
- NdG
-
- 1
- <
- 1.6
- ;
- and
- 73.
- <
- vdG
-
- 1
- <
- 120.
- ,
- where NdG1 represents a refractive index of a material of the first lens for a d-line, and νdG1 represents an Abbe number of the material of the first lens for the d-line.
Dependencies are inferred from the claim text.