Patent ID: 8223615

Claim:
A compatible near field optical recording/reproducing apparatus that compatibly uses an information storage medium using near field light and an information storage medium using far field light, the apparatus comprising: a first light source; a solid immersion lens unit, comprising: a first lens that has an aspherical surface in which light incident from the first light source is condensed; and a second lens that realizes a high numerical aperture via a near field effect by light condensed by the first lens and has an aspherical surface, the second lens comprising an addition lens that contacts a spherical surface, the addition lens comprising an aspherical adjustment surface that faces the first lens; an effective beam size-controlling device that controls an effective size of a light beam transmitted to the solid immersion lens unit such that either near field light or far field light is transmitted to an information storage medium by the solid immersion lens unit based on whether the information storage medium is the information storage medium using near field light or the information storage medium using far field light; and a focal point adjusting optical system that adjusts a focal position of light transmitted to the information storage medium according to a type of the information storage medium.