Ricoh Company, Ltd.

Ippei Ogawa

Takuo Ohishi

Yuki Nakamura

Katsuyuki Yamada

Eiji Noda

Takanobu Matsuba

Tohru Yashiro

Hiroko Iwasaki

Kenichi Aihara

Hisamitsu Kamezaki

Yumi Mochizuki

An optical recording medium has a multi-layer structure recording layer structure recording layer portion including plural recording layers provided with tracks for guiding a recording light and being adapted to record data, where recording condition information and recording layer identification information for the recording layers are recorded on the tracks as information signals. Test writing is conducted on a recording layer that is subject to recording to derive a suitable recording condition based on recording condition information that is recorded on the recording layer, and direct recording is conducted according to a direct recording condition.

Optical recording medium and information recording method

An optical recording medium has a multi-layer structure recording layer portion including plural recording layers provided with tracks for guiding a recording light and being adapted to record data, where recording condition information and recording layer identification information for the recording layers are recorded on the tracks as information signals. Test writing is conducted on a recording layer that is subject to recording to derive a suitable recording condition based on recording condition information that is recorded on the recording layer, and direct recording is conducted according to a direct recording condition.

Method and apparatus for recording information with a multi-layer structure

In the disclosed pulse shape modulation method, an amplitude modulation gain for a reproduced signal from an information recording medium that makes the jitter of the reproduced signal become the minimum is specified. Then, it is determined whether the amplitude modulation gain corresponding to the minimum jitter resides within a prescribed range. If the amplitude modulation gain corresponding to the minimum jitter is outside the prescribed range, the pulse shape of the pulsed laser beam is modulated.

Pulse shape modulation and information recording and reproducing technique using pulsed laser beam

An information recording medium including a transparent substrate, and a recording layer or a metallic layer formed on the transparent substrate directly or through an undercoat layer, with an amplitude attenuation time of 1 second or less and/or a vibration frequency attenuation time of 3 seconds or less, when vibrated in the direction perpendicular to the flat surface of said information recording medium, or wherein when the information recording medium is in-plane vibrated in the direction perpendicular to the extending direction of information recording, reproducing and/or deleting tracks, a maximum in-plane deviation of a recording, reproducing or deleting position in the tracks in the perpendicular direction from a correct recording, reproducing or deleting position in the tracks is 12.5&#xd7;d or less wherein d is an average distance between the adjoining tracks measured in the direction perpendicular to the extending direction of the tracks, and an acceleration of the information recording medium in the perpendicular direction is 0.25 m/sor less.

Information recording medium

A phase-change optical information recording medium including a substrate and a recording layer provided on the substrate, the recording layer including a phase-change recording material capable of recording information, reproducing recorded information, and erasing recorded information reversibly with reversible phase changes in the phase-change recording material, with successive formation of a recording mark with a low reflectivity and a length of at least one unit extending in an optical recording scanning direction, and a space with a high reflectivity and a length of at least one unit extending in the optical recording scanning direction, wherein information is recorded by a plurality of signals being recorded in the recording layer, each signal constituting a recording mark area including a recording initiation marking portion with (a) a length of at least two times a minimum length of the recording mark and (b) a width (W1) of at least 1.1 times an average width (W2) of the other portion of the recording mark area.

Phase-change optical information recording method

The optical recording medium at least a transparent substrate; a reflection layer; and a print layer. The print layer has a multilayer structure in which a plurality of ink layers made from different inks that have different specific gravities are stacked. A sum of products of viscosity &ggr; (in poise) and weight M (in gram) of the ink used to form the ink layer in the print layer satisfies a relation 30&lE;&Sgr;&ggr;iMi (g&middot;Poise)&lE;150.

Optical recording medium and method of manufacturing the optical recording medium

A phase-change optical information recording medium including a substrate and a recording layer provided on the substrate, the recording layer including a phase-change recording material capable of recording information, reproducing recorded information, and erasing recorded information reversibly with reversible phase changes in the phase-change recording material, with successive formation of a recording mark with a low reflectivity and a length of at least one unit extending in an optical recording scanning direction, and a space with a high reflectivity and a length of at least one unit extending in the optical recording scanning direction, wherein information is recorded by a plurality of signals being recorded in the recording layer, each signal constituting a recording mark area including a recording initiation marking portion with (a) a length of at least two times a minimum length of the recording mark and (b) a width (W ) of at least 1.1 times an average width (W ) of the other portion of the recording mark area.

Phase-change optical information recording medium

Both a low-linear-velocity recording and a high-linear-velocity recording can be effectively performed by an optical recording method for recording information on a phase-change optical recording medium which is recordable at a low linear velocity and a high linear velocity greater than the low linear velocity. A ratio (Pel/Pwl) of an erasing power Pel to a recording power Pwl in the low-linear-velocity recording and a ratio (Peh/Pwh) of an erasing power Peh to a recording power Pwh in the high-linear-velocity recording are determined so that the ratio (Pel/Pwl) and the ratio (Peh/Pwh) satisfy the relationship &lcub;(Pel/Pwl)<(Peh/Pwh)&rcub;.

Growing community of inventors

Kanagawa, Japan

Ippei Ogawa