Patent ID: 6031792
Filing Date: 2000-02-29
Classification: G11B

Abstract:
An apparatus adapted for selectively reproducing information from a recording medium selected from a plurality of differing media types by applying light to an information recording layer through a transparent substrate having a thickness, said apparatus comprising:light-generating means for generating light to be applied to the information recording layer of the recording medium;light-applying means for converging the light generated by said light-generating means and applying it to the information recording layer of said recording medium;light-receiving means for receiving the light reflected by said recording medium; anda discriminator operably interconnected with the light-receiving means including focus-measuring means for measuring the focus of the light reflected by said recording medium, wherein the focus-measuring means is adapted to generate a media type signal representative of the focus of the light reflected by the recording medium whereby the media type signal indicates which of the plurality of differing media types comprises the recording medium.