Patent ID: 8081557

Claim:
An optical pickup apparatus comprising: a laser light source configured to emit laser light having a predetermined wavelength; an objective lens configured to apply the laser light to an optical recording medium; a reflection mirror interposed in a optical path between the laser light source and the objective lens, the reflection mirror configured to reflect the laser light so that the laser light is allowed to be incident on the objective lens; a photodetector configured to receive reflected light obtained by reflecting the laser light from the optical recording medium; and a beam splitter interposed in a optical path between the laser light source and the reflection mirror, and arranged so that the laser light is reflected from the beam splitter in a direction of the reflection mirror, and the reflected light is allowed to pass through the beam splitter in a direction of the photodetector, the beam splitter including a first reflective film configured to generate a first phase difference corresponding to the predetermined wavelength with respect to the laser light, the reflection mirror including a second reflective film configured to generate a second phase difference that compensates for the first phase difference corresponding to the predetermined wavelength with respect to the laser light, so that a combined phase difference of the first phase difference and the second phase difference becomes substantially quarter-wave with respect to the laser light emitted from the laser light source.