摘要:
An optical disk is adapted for use in an optical disk unit which irradiates a light beam spot on a target track on the optical disk and controls tracking of the light beam spot based on a tracking error signal which is generated based on a reflected light beam from the optical disk. The optical disk includes a disk shaped substrate, a spiral or concentric guide tracks provided on the substrate, a writable region provided on the substrate between two mutually adjacent track turns of the guide track, and a preformed track provided within the guide track and prerecorded with read-only information in a form of variations of a topological feature. The guide track and the topological feature have mutually different height positions so that a tracking error signal which is generated when the light beam spot scans the guide track has the same amplitude as a tracking error signal which is generated when the light beam spot scans the preformed track, and the height positions of the guide track and the topological feature are different from a height position which generates a maximum tracking error signal amplitude when scanned by the light beam spot.
摘要:
An optical disk is made up of a disk-shaped substrate having a surface, a first track and a second track provided on the surface of the substrate, where the first and second tracks are two mutually adjacent concentric tracks or two mutually adjacent track turns of a single spiral track, the first track extends along a first center line and the second track extends along a second center line, and an identification signal recording part extending along a third center line and prerecorded with an identification signal including at least a sector number and a track number for identifying a position on the optical disk. The third center line is arranged between the first and second center lines, and the identification signal prerecorded in the identification signal recording part is common to the first and second tracks on both sides of the identification signal recording part.
摘要:
A projector device includes an acquisition unit configured to acquire an image from an image pickup unit that picks up the image on a projection side of a transmissive type screen to which a display image is projected by a projector; a detection unit configured to detect a position where a luminance is changed on the acquired image; and an output unit configured to output the position on the acquired image where the change in luminance is detected.
摘要:
A magnetic disc has a data area including a magnetic data zone and nonmagnetic portions for physically separating the magnetic data zone, and also has a servo area provided with a magnetic pattern made up of magnetic portions and nonmagnetic portions. The servo area includes a belt-like area elongated in a radial direction of the magnetic disc and having a circumferential length at least twice as long as a unit length readable by a magnetic head in a circumferential direction of the magnetic disc. The belt-like area is provided with magnetic regions and nonmagnetic regions alternating with each other in the radial direction of the disc, where each of the magnetic and nonmagnetic regions extends from the first end to the second end of the belt-like area that are spaced from each other in the circumferential direction of the disc.
摘要:
A magneto-optical recording medium (D1) includes a soft magnetic layer (2) and a magneto-optical recording layer (3) laminated sequentially onto a substrate (1) and is provided with a plurality of grooves (G) and lands (L). The product of the saturation magnetic flux density and thickness of the soft magnetic layer (2) is made different for the respective grooves (G) and lands (L). Thus, with respect to each groove (G) and each land (L), the magnetic focusing effect can be enhanced for one of these with a greater product of saturation magnetic flux density and thickness of the soft magnetic layer (2), while the effect can be weakened for the other one with a smaller product of saturation magnetic flux density and thickness of the soft magnetic layer. This enables the incidence of cross-writing to be suppressed.
摘要:
The magneto-optical recording medium (X1) includes a resin substrate (S1) having a pre-groove surface (1a) on which pre-grooves (1b) are formed, a recording magnetic section (11) performing a recording function and a reproduction function, a soft magnetic plating layer (12) provided between the resin substrate (S1) and the recording magnetic section (11), and a bonding layer (13) interposed between the resin substrate (S1) and the soft magnetic plating layer (12) for enhancing attachment between the resin substrate (S1) and the soft magnetic plating layer (12).
摘要:
On the assumption that a phase difference caused by a birefringence at the substrate is &phgr;br while a one caused by the magneto-optic Kerr effect of the recording layer is &phgr;MO, the magneto-optical recording medium formatted to record information in the groove meets the conditions: −20°
摘要:
An optical recording medium in which information can be recorded in tracks formed by both lands and grooves provided between lands, and rows of prepits corresponding to preformat information in both adjacent lands and grooves are formed by deviating in the circumferential direction. Counting grooves for counting tracks are formed at both sides of the row of prepits for the land, the prepit for the groove has a depth or width different from that of the groove, the counting groove has a depth or width different from that of the groove, and the prepit for the land is formed narrower and/or shallower than the counting groove.
摘要:
A projector device includes an acquisition unit configured to acquire an image from an image pickup unit that picks up the image on a projection side of a transmissive type screen to which a display image is projected by a projector; a detection unit configured to detect a position where a luminance is changed on the acquired image; and an output unit configured to output the position on the acquired image where the change in luminance is detected.
摘要:
A magnetic disk apparatus includes a magnetic disk, a magnetic head, a servo reproduction signal generator and a magnetic head controller. The disk includes a data recording area and a servo-pattern area. The data recording area includes a non-magnetic area scattered with magnetic regions, and the servo-pattern area includes uniformly magnetized magnetic regions larger than the magnetic regions in the recording area. The magnetic head reciprocates radially of the disk, giving a magnetization direction to the magnetic regions in the data recording area and reading the magnetization direction of the magnetic regions in the data recording area and the servo-pattern area. The servo reproduction signal generator reads the servo-pattern area, using the magnetic head, via an absolute-value calculation circuit to generate a servo reproduction signal before the recording or reading with respect to the data recording area. The magnetic head controller performs recording or reproducing with respect to the data recording area by controlling the magnetic head based on the servo reproduction signal.