Abstract:
An objective optical system for information recording/reproducing, at least one of optical surfaces of the objective optical system comprising a diffraction surface including a first region contributing to converging first, second and third beams and including a diffraction structure formed such that use diffraction orders for the first, second and third beams are 1st-orders and a condition 0.03
Abstract:
An objective optical system for information recording/reproducing, at least one of optical surfaces of the objective optical system comprising a diffraction surface including a first region contributing to converging first, second and third beams and including a diffraction structure formed such that use diffraction orders for the first, second and third beams are 1st-orders and a condition 0.03