Abstract: A magnetic recording and reproducing apparatus and a method of controlling the same, capable of increasing the output of a position control signal and performing a precise positioning control of a magnetic head. The magnetic recording and reproducing apparatus has: a magnetic recording medium on which a positional information is recorded in the form of burst signal groups each consisting of either one of a single concave portion and a single convex portion of a predetermined concavo-convex pattern formed of a magnetic layer; a gate circuit; and an integrator for calculating a area integral of a reproduced signal corresponding to each of the burst signal groups.

Abstract: A magnetic recording and reproducing apparatus has a magnetic recording medium onto which servo information including position information is recorded by a concavo-convex pattern formed by a magnetic layer and a signal processing circuit that generates position control signal of a magnetic head based on amplitude values of fundamental wave component and at least one harmonic component in a reproduced signal of the position information. This magnetic recording and reproducing apparatus can increase the output of the position control signal and also increase the accuracy of the positioning control of the magnetic head.

Abstract: A memory system, which is connected to a host device, includes a memory, a host interface which receives a command and an address, which are output from the host device, and a controller which operates in one of a first mode in which the controller converts the address which is received by the host interface and accesses the memory by using the converted address, and a second mode in which the host device directly accesses the memory by using the address which is received by the host interface, the controller controlling switching between the first mode and second mode in accordance with the command.

Abstract: Data track pattern regions, in which data track patterns are formed by concave/convex patterns, and servo pattern regions, in which servo patterns are formed by concave/convex patterns, are provided on a magnetic recording medium so as to be alternately disposed in a circumferential direction. At least one predetermined region that differs to the data track pattern regions is provided between two servo pattern regions that are adjacent in a circumferential direction. A concave/convex pattern including a plurality of first convex parts formed continuously in a radial direction is formed in each predetermined region.

Abstract: A recording/reproducing apparatus includes: a magnetic recording medium on which data track patterns are formed in data track pattern regions by a pattern with recording regions and non-recording regions and on which servo patterns are formed in servo pattern regions by the pattern; a recording head that writes signals on the medium; a reproducing head that reads signals written on the medium; and a control unit that controls the writing of signals by the recording head and the reading of signals by the reproducing head and measures a predetermined parameter for at least one of the recording head and the reproducing head by writing and reading measurement signals on the medium.

Abstract: A magnetic recording and reproducing apparatus includes: a magnetic recording medium onto which servo information including position information is recorded by a plurality of concavo-convex patterns formed by a magnetic layer; a gate circuit that extracts a part of a reproducing signal of the concavo-convex patterns by removing an end of a signal corresponding to a concave portion or a convex portion of the concavo-convex patterns from the reproducing signal; a first integrator that obtains area integral of an extracted reproducing signal; and a second integrator that adds respective signals after area integral is obtained to each other to generate a position control signal for controlling a position of a magnetic head. Thus, the magnetic recording and reproducing apparatus can make an output of the position control signal larger and can perform positioning control for the magnetic head with high precision.

Abstract: A system constituted by a product information supply server 2, an automatic graphic server 3, an order processing server 4 and a product information database 1. The servers 2, 3 and 4 may be connected to product information database 1 on a network 5, wherein product information is supplied and an order is accepted on the basis of a request from a customer terminal 6. The product information supply server 2 searches and supplies various pieces of product information in accordance with the request from the customer terminal 6. The product information supply server 2 searches a product specification database 11 on the basis of the product specification information entered from the customer terminal 6, extracts a call number of a relevant product from the product specification database 11, and supplies the call number of the relevant product together with price information and delivery to the customer terminal 6.

Abstract: A magnetic recording and reproducing apparatus includes a separator and first and second amplifiers. The separator separates a servo data signal and a user data signal, both reproduced by a reproducing head. The first and second amplifiers are connected to the output stage of the separator to increase the amplitude ratio of the servo data signal to the user data signal. The magnetic recording and reproducing apparatus can precisely decode the servo data along with the user data, and can achieve a highly precise servo control.

Abstract: A magnetic recording and reproducing apparatus and a method of controlling the same, capable of increasing the output of a position control signal and performing a precise positioning control of a magnetic head. The magnetic recording and reproducing apparatus has: a magnetic recording medium on which a positional information is recorded in the form of burst signal groups each consisting of either one of a single concave portion and a single convex portion of a predetermined concavo-convex pattern formed of a magnetic layer; a gate circuit; and an integrator for calculating a area integral of a reproduced signal corresponding to each of the burst signal groups.

Abstract: A magnetic recording and reproducing apparatus has a magnetic recording medium onto which servo information including position information is recorded by a concavo-convex pattern formed by a magnetic layer and a signal processing circuit that generates position control signal of a magnetic head based on amplitude values of fundamental wave component and at least one harmonic component in a reproduced signal of the position information. This magnetic recording and reproducing apparatus can increase the output of the position control signal and also increase the accuracy of the positioning control of the magnetic head.

Abstract: A magnetic recording and reproducing apparatus includes: a magnetic recording medium onto which servo information including position information is recorded by a plurality of concavo-convex patterns formed by a magnetic layer; a gate circuit that extracts a part of a reproducing signal of the concavo-convex patterns by removing an end of a signal corresponding to a concave portion or a convex portion of the concavo-convex patterns from the reproducing signal; a first integrator that obtains area integral of an extracted reproducing signal; and a second integrator that adds respective signals after area integral is obtained to each other to generate a position control signal for controlling a position of a magnetic head. Thus, the magnetic recording and reproducing apparatus can make an output of the position control signal larger and can perform positioning control for the magnetic head with high precision.

Abstract: On a magnetic recording medium, M sets of burst patterns are formed along a direction of rotation of a substrate in each burst pattern region, where M is a natural number of two or higher. Each burst pattern is formed so as to include two types of burst signal units that are positioned at different distances from a center of data track patterns and have an equal length along a radial direction of the substrate. The length along the radial direction is (2·M/N) times the track pitch, where N is a natural number of two or higher.

Abstract: On a magnetic recording medium, M sets of burst patterns are formed along a direction of rotation of a substrate in each burst pattern region, where M is a natural number of two or higher. Each burst pattern is formed so as to include two types of burst signal units that are positioned at different distances from a center of data track patterns and have an equal length along a radial direction of the substrate. The length along the radial direction is (2·M/N) times the track pitch, where N is a natural number of two or higher.

Abstract: An information recording medium excellent in surface smoothness. The information recording medium has a data track pattern and a servo pattern formed on at least one surface of a substrate by a concave/convex pattern including a plurality of convex portions. The concave/convex pattern has concave portions each having a non-magnetic material embedded therein. An A concave/convex pattern forming the servo pattern includes a plurality of servo convex portions formed in a manner associated with servo data. At least part of the plurality of servo convex portions are formed by a B concave/convex pattern including a plurality of non-servo convex portions. This arrangement makes it possible to maintain excellent surface smoothness within a servo pattern area, thereby enabling the recording/reproducing apparatus to execute stable recording and reproducing on and from the information recording medium.

Abstract: A reliable magnetic recording medium is provided which comprises a servo signal unit portions formed in a concavo-convex shape, easily produced, and resistant to tracking error. Also provided are a magnetic recording/reproducing apparatus which incorporates the magnetic recording medium, and a stamper for manufacturing the magnetic recording medium with efficiency. The magnetic recording medium includes a recording layer divided into a plurality of data areas and a plurality of servo areas to record information. The recording layer is formed in a concavo-convex shape in each servo area, with a servo signal unit portions formed as either a convex portions or a concave portions of the concavo-convex shape. Of the servo signal unit portions, the burst signal unit portion for tracking is generally elliptical in shape when viewed from the direction of thickness.

Abstract: A magnetic recording and reproducing apparatus includes a separator and first and second amplifiers. The separator separates a servo data signal and a user data signal, both reproduced by a reproducing head. The first and second amplifiers are connected to the output stage of the separator to increase the amplitude ratio of the servo data signal to the user data signal. The magnetic recording and reproducing apparatus can precisely decode the servo data along with the user data, and can achieve a highly precise servo control.

Abstract: A data track area and a servo pattern area are formed on a magnetic recording medium by embedding a nonmagnetic material inside concaves in a plurality of types of convex/concave patterns formed of a magnetic material on a substrate. The servo pattern area includes a plurality of types of first functional areas, in which control signals for disk access are recorded during manufacturing using the convex/concave patterns, and a second functional area, in which a convex/concave pattern of a different type to the convex/concave patterns of the respective first functional areas is formed and in which the nonmagnetic material is embedded so that an average height within the second functional area is substantially equal to an average height in the data track area.

Abstract: A system constituted by a product information supply server 2, an automatic graphic server 3, an order processing server 4 and a product information database 1. The servers 2, 3 and 4 may be connected to product information database 1 on a network 5, wherein product information is supplied and an order is accepted on the basis of a request from a customer terminal 6. The product information supply server 2 searches and supplies various pieces of product information in accordance with the request from the customer terminal 6. The product information supply server 2 searches a product specification database 11 on the basis of the product specification information entered from the customer terminal 6, extracts a call number of a relevant product from the product specification database 11, and supplies the call number of the relevant product together with price information and delivery to the customer terminal 6.

Abstract: After data recording or reproduction is finished, servo control is stopped within a predetermined time to disable a positional compensation output to a head. While servo control is being stopped, servo data recorded in a medium is monitored. When the head is moved on the medium further than a predetermined distance, servo control is activated to start a positional compensation output to the head. The stop/start of the servo control is implemented by software embedded in the CPU of a disk apparatus.

Abstract: The present invention relates to a magnetic recording medium and a magnetic recording/reproducing apparatus for the same. In the magnetic recording medium there are provided a read/write region which permits modification of written data and a read-only region dedicated to the reading of data, which is used for reading only once writing is done. In recording servo information to a data format region of the magnetic recording medium, the time width of servo information in the read-only region is set shorter than that in the read/write region.