Abstract:
After the initiation of writing, an output signal from an LPF is sampled in correspondence with a portion with a predetermined pulse width of recording data, so as to obtain a pit level. In the resultant signal, its varying portions which correspond to the multi-pulse trains of the write signal are smoothed. A controller modifies a level of a target level signal to be supplied to an APC circuit in such a manner that the pit level becomes an optimum pit level which has been obtained prior to the initiation of writing.
Abstract:
An optical disc device includes a laser light source for radiating a laser light beam illuminated via an objective lens on a signal surface of an optical disc, a return light detection unit for detecting the reflected light radiated from the laser light source and reflected from the signal surface of the optical disc, a disc discriminating unit for discriminating the type of the optical disc based on a detection output of the return light detection unit, a unit for detecting tracking error signals of plural different types of different detection systems based on the detection output of the return light detection unit, a tracking unit for displacing the objective lens along the radius of the optical disc responsive to the tracking error signals for tracking-controlling a laser spot of the laser light focussed on the signal surface of the optical disc and a controlling unit for switching the detection system based on a discriminating output by the disc discriminating unit for selecting one of the plural types of the tracking error signals appropriate to the types of the optical discs (eg CD or DVD).
Abstract:
A laser light beam is illuminated via an objective lens on the signal surface of an optical disc and the objective lens is displaced by a servo processor along the optical axis for focussing search to generate focussing error signals by a RF block from a detected output of the laser light by the signal surface of the optical disc. Based on these focussing error signals, a system controller discriminates the types of the optical disc having different numbers of signal recording layers for setting an operating mode in keeping with the types of the optical disc.
Abstract:
An optical disc device includes a laser light source for radiating a laser light beam illuminated via an objective lens on a signal surface of an optical disc, a return light detection unit for detecting the reflected light radiated from the laser light source and reflected from the signal surface of the optical disc, a disc discriminating unit for discriminating the type of the optical disc based on a detection output of the return light detection unit, a unit for detecting tracking error signals of plural different types of different detection systems based on the detection output of the return light detection unit, a tracking unit for displacing the objective lens along the radius of the optical disc responsive to the tracking error signals for tracking-controlling a laser spot of the laser light focussed on the signal surface of the optical disc and a controlling unit for switching the detection system based on a discriminating output by the disc discriminating unit for selecting one of the plural types of the tracking error signals responsive to the types of the optical discs.
Abstract:
PROBLEM TO BE SOLVED: To resolve a problem occurring when a plurality of monitor ICs are used, namely, a problem of difference in current consumption between the monitor ICs causing difference in remaining battery capacity and loss of a balance.SOLUTION: A plurality of battery cells in series connection are classified into at least two groups, a first group and a second group. First and second monitoring units detect voltages of battery cells in the first and second groups, respectively. One terminal of the series connection and one power terminal of the first monitoring unit are connected, the other power terminal of the first monitoring unit and one power terminal of the second monitoring unit are connected, and the other power terminal of the second monitoring unit and the other terminal of the series connection are connected. A current cancellation unit configured to cancel a differential current that is a difference between a first current flowing through the first monitoring unit and a second current flowing through the second monitoring unit is disposed between a connection point between the other power terminal of the first monitoring unit and one power terminal of the second monitoring unit and a connection point in the middle of the series connection.
Abstract:
PROBLEM TO BE SOLVED: To be able to prevent breakdown voltage at insulating parts from becoming high, and to directly transmit signals between a controller of each battery pack and an integrated controller without using a microprocessor.SOLUTION: N pieces of battery packs MOD1-MODN are connected in series. Each of the battery packs MOD1-MODN has an insulation interface that insulates between the battery packs. Through photocouplers IFS1-IFSN as an insulation interface, a controller CNT of each battery pack performs communication between upper or lower battery packs, or between an outer integrated controller. The integrated controller ICNT is connected to the lowermost battery pack MOD1. The integrated controller ICNT controls a whole battery system. The integrated controller ICNT receives information on inner state of each battery pack and controls charge and discharge of each battery pack by supplying and stopping the charging current and discharging current to each battery pack.
Abstract:
PROBLEM TO BE SOLVED: To appropriately conduct data reading and writing for an optical disk, in which a recording density is made high, while maintaining the interchangeability with an optical disk having an existing format. SOLUTION: The wavelength of optical beams, with which an optical disk is irradiated, is set to 780 nm and a numerical aperture NA of an objective lens is set to 0.50±0.01 or 0.55±0.01. When signal reading and writing are conducted for a double density CD-R, the CD-R is rotated with an N times linear velocity (where N is the magnification with respect to a standard velocity) of 0.9±0.05 m/sec and the characteristic of an equalizer is boosted and set in the vicinity of the frequency, that is N times 1 MHz, so as to obtain 3 to 4 dB gain.
Abstract:
PROBLEM TO BE SOLVED: To realize a recording/reproducing system which can appropriately perform recording and reproduction of data or/from an optical disk with enhanced recording density, and can comply with the optical disk of a present format. SOLUTION: A first interleaver 14 and a second interleaver 15 with a different delay parameter, respectively are provided for a CIRC encoder 12 to perform error correcting coding processing by CIRC and these switching are performed according to the recording density of the optical disk 100 to perform the recording of data. Besides, a first de-interleaver 25 corresponding to the first interleaver 14 and a second de-interleaver 26 corresponding to the second interleaver 15 are provided in a CIRC decoder 23 and these switching are performed according to the recording density of the optical disk 100 to perform the reproduction of data.