摘要:
Prevented is the reliability loss in phase change optical recording media during high-temperature storage, and also prevented is the phenomenon of self-erase by which a part of record marks having been formed in the media are erased due to the lateral heat diffusion into the recording layer while recording laser beams are irradiated to the media. The optical recording medium disclosed has a recording layer of a phase change type and is applied to driving units for overwriting it at a linear velocity of V.sub.0. The medium is so designed as to satisfy the requirement of 1
摘要:
In a phase change-type optical recording medium of absorption coefficient control structure used by land/groove recording system, difference in reproduction characteristics between the land and the groove is minimized while ensuring sufficient output of the tracking signal. In the optical recording medium of the present invention, light absorption coefficient at the wavelength of said recording/reproducing beam is such that: Ac/Aa.gtoreq.0.8 when light absorption coefficient in crystalline region is Ac and light absorption coefficient in amorphous region is Aa; relation between groove width W.sub.G and land width W.sub.L is such that: x=2W.sub.G /(W.sub.L +W.sub.G).gtoreq.1.03; and the relation: .lambda.max.sup.i
摘要:
In an optical recording medium comprising a phase change recording layer (4) containing Sb and optionally, Te and/or In as a main component, the recording layer is able to be crystallized to provide a crystallized region which contains rhombohedral crystals consisting essentially of Sb and is substantially free of a crystal phase other than the rhombohedral crystals. When the recording layer contains a rare earth element, Zr, Hf, Ti or Sn as an auxiliary component, the medium has a dielectric layer (31) composed of silicon oxide, silicon nitride, aluminum oxide, or a mixture of zinc sulfide and at least 30 mol % of silicon oxide, disposed contiguous to and in front of the recording layer (4) as viewed from the recording/reading beam incident side. The medium has a high transfer rate and improved thermal stability.
摘要:
A method for recording/reproducing an optical recording medium of phase change type is provided. The method enables a high density recording while increase in the cross erase is suppressed. The method also enables an accurate tracking while increase in the crosstalk is suppressed. The method is adapted for use with an optical recording medium of phase change type comprising a substrate having a thickness of up to 0.8 mm wherein lands and grooves on opposite sides of the land are formed on the surface, and both the lands and the grooves are used as recording tracks, and the medium is overwritten at a recording power Pw (mW) and an erasing power Pe (mW) which meet the relation: (Pw/Pe).times.k.sup.2 .ltoreq.8.5, when the medium has a recording track pitch P (.mu.m), the recording/reproducing optical system has a numerical aperture NA, and the recording/reproducing light has a wavelength .lambda. (.mu.m) which meet the relation: k=(.lambda./NA)/P.gtoreq.1.78.
摘要:
In an optical recording medium including a grooved light-transparent substrate, a phase change recording layer, a dielectric layer and a reflective layer, recording is carried out by irradiating a laser beam to the recording layer through an objective lens in an optical system. The recording is carried out in a groove recording mode under the conditions: 0.48≦PT/(λ/NA)≦0.74, and PT≦0.50 μm wherein λ is a laser beam wavelength, NA is an objective lens numerical aperture, and PT is a track pitch, thereby forming a recorded mark having opposite ends extending out of the groove. This enables high density recording and increases the data transfer rate of a phase change optical recording medium.
摘要:
In an optical recording medium of land/groove recording system, a sufficient tilt margin and a reduced cross talk are realized simultaneously with a sufficiently increased output. Provided is an optical recording medium having a light-transmitting substrate formed with grooves wherein the grooves and the region between adjacent grooves are used for the recording track, and a reading beam is irradiated through the light-transmitting substrate, wherein the relations: −12.6T+15.6≦x≦25T−3.8, and 0.55≦T≦0.68 are satisfied when the reading beam has a wavelength of &lgr;, the light-transmitting substrate has a refractive index at the wavelength &lgr; of n, the reading optical system has a numerical aperture of NA, recording track pitch is PT, the groove has a depth of &lgr;/(x·n), and T is PT/(&lgr;/NA).
摘要:
Increase of jitter in a phase change optical recording medium is suppressed with no extreme decrease in the crystallization speed of the recording layer when the medium is overwritten at a high linear velocity. In addition, in a disk-shaped medium operated at a constant angular velocity, the overwriting is accomplished with the increase of jitter suppressed over the entire area of the medium. Provided is an optical recording method for recording a disk-shaped optical recording medium having a phase change recording layer which is rotated at a constant angular velocity, wherein amorphous recorded marks are formed in the recording layer. In this method, the minimum recorded mark is formed such that WL/ML incrementally or gradually decreases from the radially inner side to the radially outer side of the optical recording medium, when the minimum signal has a length of SL, and when the minimum recorded mark corresponding to said minimum signal has its maximum width of MW, EW is 0.1 MW; the position on the leading edge side of the recorded mark at the width of EW is designated effective leading edge; and the position on the trailing edge side of the recorded mark at the width of EW is designated effective trailing edge; the distance between the effective leading edge and the effective trailing edge is designated effective length ML; and the distance between the effective leading edge and the position at which the width starts to decrease on the trailing edge side is designated WL.
摘要翻译:当以高线速度重写介质时,抑制了相变光记录介质中的抖动的增加,而在记录层的结晶速度没有极度降低的情况下。 另外,在以恒定的角速度操作的盘形介质中,通过在介质的整个区域上抑制的抖动的增加来实现重写。 提供了一种用于记录具有以恒定角速度旋转的相变记录层的盘形光学记录介质的光学记录方法,其中在记录层中形成非晶体记录标记。 在该方法中,形成最小记录标记,使得W L L / M L L从光记录介质的径向内侧向径向外侧逐渐地逐渐减小 当最小信号具有长度为S L L时,当对应于所述最小信号的最小记录标记具有M W的最大宽度时,E W SUB>为0.1MW; 记录标记的前缘侧的位置在E 的宽度被指定为有效前沿; 并且在E< W>宽度的记录标记的后缘侧的位置被指定为有效后缘; 有效前沿和有效后沿之间的距离被指定为有效长度M L L; 并且有效前沿与后缘侧宽度开始减小的位置之间的距离被指定为W L L。
摘要:
When information is recorded in an optical recording medium having a recording layer by irradiating a laser beam thereto through an optical system, the recording is carried out under the conditions: &lgr;/NA≦680 nm and n·Tw≦22 ns wherein the laser beam has a wavelength &lgr;, the optical system includes an objective lens having a numerical aperture NA, the window margin is Tw, and a signal length corresponding to the shortest recorded mark is n·Tw. The method provides for a high transfer rate and minimizes the jitter.
摘要翻译:当通过光学系统照射激光束将信息记录在具有记录层的光学记录介质中时,在λ/ NA <= 680nm和n.Tw <= 22ns的条件下进行记录,其中 激光束具有波长λ,光学系统包括具有数值孔径NA的物镜,窗口边距为Tw,与最短记录标记对应的信号长度为n.Tw。 该方法提供高传输速率并使抖动最小化。
摘要:
In an optical recording medium wherein grooves or lands formed on the supporting substrate are used for the recording tracks, and wherein prepits are also formed, production of the supporting substrate and high density recording are facilitated. This medium comprises a supporting substrate and a recording layer on the substrate wherein the surface of the supporting substrate on which the recording layer is formed is formed with alternating continuous convex portions and continuous concave portions which are substantially parallel to each other. The adjacent continuous convex portions are connected by bridging convex portions extending in transverse direction, and the bridging convex portion has a planar configuration that its width is minimum at or near the center between the adjacent continuous convex portions. The supporting substrate is produced by using a master disk which has a resist layer formed with mother patterns of each of the continuous convex portions, continuous concave portions, and prepits. In the production of the master disk, the resist layer is intermittently irradiated with one exposure beam, and the area irradiated is used as the mother pattern of the continuous concave portions or convex portions, and the area which was not irradiated is used as the mother pattern of the prepits.
摘要:
In a phase change-type optical recording medium of absorption coefficient control structure used by land/groove recording system, difference in reproduction characteristics between the land and the groove is minimized while ensuring sufficient output of the tracking signal. In the optical recording medium of the present invention, light absorption coefficient at the wavelength of said recording/reproducing beam is such that: Ac/Aa≧0.8 when light absorption coefficient in crystalline region is Ac and light absorption coefficient in amorphous region is Aa; relation between groove width WG and land width WL is such that: 0.97≦2WG/(WL+WG)