Matsushita Electric Industrial Co., Ltd.

Panasonic Intellectual Property Management Co., Ltd.

Tsutomu Kai

Shuichi Yoshida

Kiyoshi Masaki

Masaharu Imura

Noritaka Akagi

Kazuhiro Mihara

Takanori Okada

Kazuhiko Kouno

Masanori Harui

Masahito Matsunami

Takumi Matsuura

Yasumori Hino

Shinji Inoue

Junichi Minamino

Masahiro Yamamoto

Harumitsu Miyashita

Kazuyuki Murata

Yasuhiro Kuwahara

Akio Kojima

Takeshi Shimamoto

Yoshihiro Tosaki

Teruyuki Naka

Hiromichi Shimada

Naoyuki Ito

Tsutomu Mikami

Takeshi Okuno

Yoshitaka Mitsui

Hitoshi Ono

Isao Takemoto

Hideo Koseki

Hisashi Tomitani

Shouzou Fujiwara

Yasuo Kashiwagi

Tomoko Suetake

An inspection method for a recordable optical disc includes focusing laser light on a recording layer and obtaining a data signal dependent on the laser light reflected by the recording layer. The inspection method also includes determining whether the optical disc includes a defect or not by identifying a first period every second period in the obtained data signal obtained, the first period being a period in which a signal level of the data signal is lower than a predetermined value, and each of the second periods corresponding to an ECC block, and outputting a result of the determination.

Inspection method for optical disc

A disk drive apparatus for a disk having helically-formed or concentric circle-like formed tracks includes a spindle motor for controlling a rotation of the disk; a pick-up device for recording or reproducing information on or from the disk; a stepping motor for moving the pick-up device in a radial direction of the disk in accordance with a drive current; a system controller for tracking a rotation speed of the spindle motor and for outputting command signals according to the rotation speed of the spindle motor; and a stepping motor controller for controlling the stepping motor by changing a slope of a rising part and a falling part of a waveform of the drive current of the stepping motor according to the command signals.

Disk drive apparatus

A disk apparatus includes a pick-up for reading/writing signals from/on a disk; a pick-up base provided with the pick-up; a traverse motor for moving the pick-up in a radial direction of said disk; a feed screw rotated by the traverse motor and provided with a thread groove on its periphery; a rack having a fixing portion fixed to the pick-up base and a nut portion engaged with the thread groove; a guiding mechanism for guiding the pick-up movably in a radial direction of the disk; and a cantilever parallel spring for connecting the fixing portion to the nut portion of the rack, displaceably in a radial direction of the feed screw.

Stepping motor controlling method and disk apparatus

In a DVD player, when data information in a DVD disk is played back, it is judged whether the data information is protected by a copyright or not on the basis of disk control information. Further, it is judged whether the DVD disk is writable or not, based on whether the DVD disk is provided with a wobble or not. Thus, if the data information is protected by the copyright and the DVD disk is writable, a playback of the DVD disk is prevented so that an illegal use of the DVD disk, which infringes the copyright, is effectively prevented.

Optical disk, method of reproducing and copying optical disk, and method of preventing illegal use of optical disk

An information recording method of recording information, in which laser light is applied to a recording medium while depending on predetermined information said laser light is modulated and the intensity of said light is controlled to form recording mark areas at which reflectivity of said recording medium changes, depending on the intensity of said applied light, wherein before starting data recording, said light is applied to said recording medium at predetermined light intensity, reflection light from said recording mark areas of said recording medium is received, the amount of said reflection light is detected, and a light intensity controlling reference value is calculated on the basis of the amount of said detected light, and during data recording, reflection light from said recording mark areas of said recording medium is received, the amount of said reflection light is detected, and a light intensity controlling detection value is calculated on the basis of the amount of said detected light, corrected light intensity is obtained from the difference between said light controlling intensity reference value and said light intensity controlling detection value, said light intensity controlling reference value is corrected depending on said corrected light intensity, and the intensity of said laser light is controlled so that said corrected light intensity controlling reference value substantially coincides with said light intensity controlling detection value.

Information recording method and information recording apparatus

In order to determine a laser emission waveform rule for a recording medium, such as a write-once optical disc, the present invention provides an information recording apparatus, an information recording method and an information recording system capable of determining optimal recording conditions by recording data for approximately one rotation, by reproducing the recorded area, by measuring a phase error for each combination of the length of a mark and the length of a space immediately before or after the mark and by changing an emission waveform rule on the basis of the measured phase error.

Information recording apparatus using a mark edge recording

In a method of the present invention for controlling stepping motor, the stepping motor driving current is increased or reduced at a fixed inclination in proportion to the time to control the stepping motor effectively, and, a stepping motor driving current pattern is changed by &frac14; cycle or more to synchronize the state of excitation between the stepping motor driving means and the stepping motor to control the pick-up very accurately. In addition, the disk apparatus of the present invention, which uses a stepping motor is provided with a pulse rate pattern variable means, a pulse rate change proportion measuring means, and a driving voltage variable means, and when the pulse rate and the pulse rate change proportion are low, the driving voltage amplitude is lowered to reduce surplus torque generation in the stepping motor.

Stepping motor control method and disk drive apparatus

In order to correct the change in the offset and amplitude of a tracking error signal because of the change in the position of an object lens from the center of an optical pickup, the offset amount and amplitude value of the tracking error signal with respect to the displacement amount of the object lens from the center of the optical pickup are checked beforehand, and the displacement amount of the object lens is estimated on the basis of a tracking correction signal by using an object lens displacement observer. An offset detection section and an amplitude detection section detect the offset amount and amplitude value of the tracking error signal respectively, and the tracking error signal is corrected by an offset correction circuit and an amplitude correction circuit on the basis of the offset amount and amplitude value having been checked beforehand so that the offset amount and the amplitude value of the tracking error signal become identical to those obtained when the displacement amount of the object lens is zero. In addition, the offset of the tilt error signal depending on the movement direction of the optical pickup is detected and recorded beforehand, and the tilt error signal is corrected on the basis of the above-mentioned recorded offset when a rotation direction detection section detects the moving direction of the optical pickup.

Optical information recording/reproducing device

In a method of the present invention for controlling stepping motor, the stepping motor driving current is increased or reduced at a fixed inclination in proportion to the time to control the stepping motor effectively, and, a stepping motor driving current pattern is changed by 1/4 cycle or over to synchronize the state of excitation between the stepping motor driving means and the stepping motor to control the pick-up very accurately. In addition, the disk apparatus of the present invention, which uses a stepping motor is provided with a pulse rate pattern variable means, a pulse rate change proportion measuring means, and a driving voltage variable means, and when the pulse rate and the pulse rate change proportion are low, the driving voltage amplitude is lowered to reduce surplus torque generation in the stepping motor.

A liquid crystal module comprises a liquid crystal panel including mutually orthogonal row electrodes and column electrodes and a liquid crystal layer sealed between the electrodes as a display element, a row electrode driving circuit driving the row electrodes of the liquid crystal panel, and a column electrode driving circuit driving the column electrodes. A detecting electrode detects scanning signals applied to the row and column electrodes of the liquid crystal panel by electrically coupling to the electrodes with electrostatic coupling capacity. A coordinate detecting circuit converts the signals obtained from the detecting electrode into row and column coordinates. A correction arithmetic circuit corrects positional differences by using correction parameters of the device which have been obtained from output values of the coordinate detecting circuit beforehand. The display-integrated coordinate input device improves detection precision at the edges of a matrix panel.

Display-integrated coordinate input device

A coordinate input device including a matrix-type display panel having a plurality of row electrodes arranged in parallel, a plurality of column electrodes arranged in parallel, the row electrodes and the column electrodes being disposed to face each other, and liquid crystal disposed between the row electrodes and the column electrodes. The device also includes a row electrode driving circuit, a column electrode driving circuit, a controller for controlling these driving circuits, an input pad disposed to allow direct contact with the operator, and a coordinate detection circuit for calculating a coordinate value based on a signal input thereto through the input pad. When a position on the display panel is pressed with a finger, a driving signal supplied to the row electrode or the column electrode corresponding to the position is transmitted through the operator to the input pad. The coordinate of the position is detected based on the transmitted signal.

Coordinate input device

An imaging apparatus comprising a counterfeiting prevention arrangement and reliably preventing counterfeit reproduction of currency, negotiable certificates, and other registered documents is provided by preventing modification or removal of the counterfeiting prevention arrangement. Modification or removal of the counterfeiting prevention arrangement is prevented in this imaging apparatus by integrating circuit elements or components of the counterfeiting prevention arrangement with circuit elements or components of the image processors of the imaging system in a single chip, or sealing these components in a single mold, effectively preventing modification or removal of the counterfeiting prevention arrangement without disabling the imaging system.

Imaging apparatus having a counterfeiting prevention function

A shift register of a CCD line image sensor is divided into two from the center thereof so as to transfer the signal electrical charge for output portions placed on both ends of the sensor, so that the line image sensor has a higher data rate, and reduced optical smearing. Furthermore, when a color line image sensor has been made using such line image sensors, the clearance of the sensor may be made smaller, and the amount of the correction smear for positioning alignment may be reduced.

Growing community of inventors

Katano, Japan

Tsutomu Kai