Multi-element grating beam splitter using double refraction to reduce optical feedback and associated light source noise

摘要

In an optical system including a multi-element grating beam splitter which includes four separate elements and an optical source with an effective aperture for generating a radiation beam to be applied to a data track of an optical storage medium, optics are disposed between the grating beam splitter and the data track of an optical storage medium which defines an optical axis along which light is projected to the data track and causes the displacement of the return beam to cause it to be substantially outside the effective aperture of the optical source to reduce optical feedback into the optical source.