公开(公告)号：US20220013144A1

公开(公告)日：2022-01-13

申请号：US17487303

申请日：2021-09-28

Applicant: Panasonic Intellectual Property Management Co., Ltd.

Inventor： Yasushi KOBAYASHI ,  Kohei NAKATA ,  Yasumori HINO

IPC: G11B20/10 ,  G11B7/0045

Abstract: A recording mark is formed on a recording medium by a predetermined recording signal, a playback signal of the recording mark formed on the recording medium is obtained, and an expected value signal of the playback signal based on the recording signal is generated. Based on an amplitude error between the playback signal and the expected value signal, and for each predetermined unit of the recording signal, a deviation amount of a mark shape of the recording mark from which the playback signal is obtained with respect to a mark shape of an ideal recording mark is calculated, and a mark shape of the recording mark formed on the recording medium is estimated. Based on the deviation amount of the mark shape of the recording mark, a correction amount is calculated for each predetermined unit of the recording signal, and a level of the recording signal is adjusted.

公开(公告)号：US20220020394A1

公开(公告)日：2022-01-20

申请号：US17281686

申请日：2019-11-08

Applicant: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.

Inventor： Kohei NAKATA ,  Yasushi KOBAYASHI

IPC: G11B20/10 ,  G11B7/0045 ,  G11B20/12

Abstract: The present disclosure provides an optical disk device capable of reproducing data recorded on a high linear density optical disk stably. The optical disk device according to the disclosure is characterized by being equipped with a recording expected waveform generation circuit which generates, at the time of recording, an expected waveform that is expected to be obtained at the time of decoding; and a recording pulse generation circuit which generates a recording pulse for driving a laser with power and a time width suitable for an amplitude value of the recording expected waveform for each sampling point of the recording expected waveform.

公开(公告)号：US20210304793A1

公开(公告)日：2021-09-30

申请号：US16963575

申请日：2019-10-23

Applicant: Panasonic Intellectual Property Management Co., Ltd.

Inventor： Yoshiaki KOMMA ,  Yasushi KOBAYASHI ,  Kazuhiro MINAMI

IPC: G11B7/1374 ,  G11B7/0045 ,  G02B13/18

Abstract: Provided is an objective lens which is used so that more information can be accumulated in a large-capacity optical disk and which has a further enhanced numerical aperture NA. The objective lens is a single lens having the numerical aperture NA and a refractive index n, and is configured so as to satisfy: NA≥0.91 and 1.61≤n

公开(公告)号：US20170263280A1

公开(公告)日：2017-09-14

申请号：US15377044

申请日：2016-12-13

Applicant: Panasonic Intellectual Property Management Co., Ltd.

Inventor： Kazuo MOMOO ,  Junichi ASADA ,  Yasushi KOBAYASHI ,  Kousei SANO ,  Yuichi TAKAHASHI

IPC: G11B7/09

CPC classification number: G11B7/0901 ,  G11B7/094 ,  G11B7/0943 ,  G11B7/131 ,  G11B7/133

Abstract: The first, third, fourth, and seventh photosensors are disposed on one side with respect to the centerline, and the second, fifth, sixth, and eighth photosensors are disposed on another side with respect to the centerline. The first and seventh photosensors are positioned between the third and fourth photosensors in the direction parallel to the centerline. The second and eighth photosensors are positioned between the fifth and sixth photosensors in the direction parallel to the centerline. The first photosensor receives overlapped light of the 0th-order light with the +1st-order diffracted light, the second photosensor receives overlapped light of the 0th-order light with the −1st-order diffracted light, each of the third to sixth photosensors receives the 0th-order light, and does not receive the +1st-order diffracted light and the −1st-order diffracted light, and each of the seventh and eighth photosensors receives at least the 0th-order light.