Zoom lens and optical apparatus including the same
AssigneeCanon Kabushiki Kaisha
InventorSatoshi Maetaki
Life of this patent
Estimating the term…
Abstract
A zoom lens includes a first lens unit having a negative refractive power and a second lens unit having a positive refractive power, which are arranged in order from the object side to the image side. The zoom lens performs zooming by changing a distance between the lens units. The first lens unit includes a compound optical element including a lens element and a resin layer having optical characteristics different from optical characteristics of the lens element, the resin layer being laminated on the lens element. An Abbe number νdg of a material of the lens element, an Abbe number νdj of a material of the resin layer, and an anomalous partial dispersion ratio ΔθgFj of the material of the resin layer are adequately set.
Claims10
A zoom lens comprising:
- a first lens unit having a negative refractive power;
- and
- a second lens unit having a positive refractive power,
- wherein the first lens unit and the second lens unit are arranged in order from the object side to the image side,
- wherein the zoom lens performs zooming by changing a distance between the lens units,
- wherein the first lens unit includes a compound optical element including a lens element and a resin layer having optical characteristics different from optical characteristics of the lens element, the resin layer being laminated on the lens element, and
- wherein the following conditions are satisfied:
- 31<|νdg−νdj|
- 26>νdj
- 0.10>|ΔθgFj|
- where νdg is an Abbe number of a material of the lens element, and νdj and ΔθgFj are an Abbe number and an anomalous partial dispersion ratio, respectively, of a material of the resin layer.
Dependencies are inferred from the claim text.