| 摘要 |
At least one exemplary embodiment is directed to an optical system which includes a compound optical element including a lens element and a resin layer having different optical characteristics and having an aspherical interface therebetween. When Rref is a reference radius of curvature of the interface within an effective diameter, L is a distance from a diaphragm, ndg and nudg are a refractive index and an Abbe number, respectively, of a material of the lens element at the d-line, and ndj and nudj are a refractive index and an Abbe number, respectively, of a material of the resin layer at the d-line, the following expressions are satisfied: <?in-line-formulae description="In-line Formulae" end="lead"?>-1.5<Rref/L<-0.3<?in-line-formulae description="In-line Formulae" end="tail"?> <?in-line-formulae description="In-line Formulae" end="lead"?>one of 0.1<|ndg-ndj| and 5<|nudg-nudj|. <?in-line-formulae description="In-line Formulae" end="tail"?>
|
