Patent ID: 8630157
Filing Date: 2014-01-14
Classification: G11B

Abstract:
1. A data reproducing apparatus comprising: a data recording medium on which an address mark string including address marks is formed, the address marks being spaced from each other by a distance depending on address data indicating an absolute position on the data recording medium; a light source unit configured to generate a light beam; a light application unit configured to split the light beam into a first branch light beam and a second branch light beam and apply the first branch light beam and the second branch light beam to the address mark string at different angles; a photodetector unit configured to detect a plurality of first reflected light beams and a plurality of second reflected light beams from the address mark string to generate image data; the first reflected light beams and the second reflected light beams resulting from the first branch light beam and the second branch light beam, respectively; and a control unit configured to reproduce address data based on the image data, wherein the photodetector unit generates, as the image data, a plurality of first address mark images and a plurality of second address mark images acquired from the first reflected light beams and the second reflected light beams, respectively, and the control unit detects one or more first distances between the first address mark images and one or more second distances between the second address mark images, calculates one or more third distances between the address marks based on the first distances and the second distances, and reproduces the address data based on the third distances.