| 摘要 |
PURPOSE:To avoid the situation that it is impossible to control convergence of laser light on a recording face because of camber and undulation, by bringing closely a transparent plate having high plane precision into contact with one face of an optical recording medium to record and reproduce signals through this transparent plate when the optical recording medium having flexibility is used to perform optical recording and reproducing. CONSTITUTION:The transparent plate having high plane precision permits light having 400-1,000nm wavelength, which is the oscillated wavelength of a semiconductor laser or a tungsten lamp used for recording and reproducing, to transmit through and has not the optical anisotropy according to circumstances and has <=200mum plane precision. An inorganic plate consisting of quartz or the like or an organic resin plate consisting of a poly(meth)acrylate resin or the like is given as a concrete example of the transparent plate. The optical recording medium has fundamentally a supporting body and a recording layer as essential constituting layers, and the supporting body and the recording layer consist of different materials or the same materials, and reflecting layer, a protective layer, and a heat insulating layer may be provided additionally. Various kinds of organic resin used in the transparent plate or metals such as copper or the like are given as a concrete example of materials of the supporting body constituting the optical recording medium. |
