Optical recording and reproducing head

摘要

An optical recording and reproducing head wherein light beams emitted from two light sources are combined and applied to a recording medium and the light beams reflected from the recording medium are drawn out in such a way that they are separated from each other. The wavelengths of the light beams from both light sources are different from each other, i.e., lambda 1, lambda 2, and the light beams from the light sources are combined by means of a polarization beam splitter, two quarter wave plates and optical filters, and are then simultaneously focussed by a single focussing lens substantially along the optical axis thereof, thereby allowing microspots of focussed light to be disposed on a disc close to each other. The light beams reflected from the disc are drawn out so as to be completely separated from each other by the polarization beam splitter owing to the difference in polarization direction.