Optical pickup apparatus and objective lens

摘要

An objective lens of an optical pickup apparatus converges a divergent light flux onto an information recording surface. The following conditional formula is satisfied: |deltaSA1/deltaU|.|deltaU|+|deltaSA2/deltaT|.|deltaT|<=0.07 lambdrms where lambd represents a wavelength of a light source, deltaSA1/deltaU represents a change of a spherical aberration for an object-to-image distance change deltaU (|deltaU|<=0.5 mm) and deltaSA2/deltaT represents a change of spherical aberration for a temperature change deltaT (|deltaT|<=30° C.), the object-to-image distance is a distance between the light source (a light emitting point) and the information recording surface.