Patent ID: 6091692
Filing Date: 2000-07-18
Classification: G11B

Abstract:
An optical information storage apparatus comprising:a light source;a polarization beam splitter reflecting light emitted from said light source and irradiating a reflected light on a recording surface of a recording medium;a Wollaston prism, made of an optically transparent material, having an input surface to which light reflected by the recording surface and transmitted through said polarization beam splitter is input, and an output surface from which light is output, said Wollaston prism being inclined within a plane which is perpendicular to a light incident surface of said polarization beam splitter and includes an optical axis along which light travels, said input surface and said output surface of said Wollaston prism being parallel to each other; anda cylindrical lens arranged between said polarization beam splitter and said Wollaston prism and having at least one cylindrical surface,said cylindrical lens having an edge line which is inclined by 45.degree. with respect to the light incident surface of said polarization beam splitter.