Patent ID: 8279540

Claim:
A compound lens comprising three or more optical elements, including first, second, and third optical components, that are cemented together into an integral component, wherein the material of the second optical element is an organic composite material, the first optical element is cemented to one surface of the second optical element, the third optical element is disposed remotest from the first optical element in an optical axis, the following conditions are satisfied: φ1ea≦φ2ea<φ2, t 2(φ1 ea )/ t 2(0)<1.0, and t 2(φ1 ea )/{ t 1(φ1 ea )+ t 3(φ1 ea )}<0.20, where φ 1 ea is a diameter of an effective surface area of the first optical element on the cemented surface between the first optical element and the second optical element, φ 2 ea is a diameter of an effective surface area of the second optical element, φ 2 is an outer diameter of the second optical element, and ti(φ) is a distance between optically effective surfaces of the i-th optical element (i=1, 2, 3) along the optical axis at diameter φ, and the second optical element has such a shape that a decrease in the distance between its optically effective surfaces along the optical axis is small in a region outside the effective surface area.