| 摘要 |
<p>A multilayer optical recording medium which satisfies a reflectance required for reproducing record of digital data which conform to the standards of CD (Compact Disc) and DVD (Digital Versatile Disc). In the multilayer optical recording medium, a first transparent board (12), an HD layer (11), a second transparent board (22) and a CD layer (21) are successively laminated. The HD layer is provided with one or more layers of semi-transparent films (31), which have reflection characteristics to a wavelength of a first reproducing signal, transmission characteristics to a wavelength of a second reproducing signal and a higher refraction index than that of the first transparent board. The CD layer is provided with a metal film (23) having reflection characteristics to the wavelength of the second reproducing signal. The total thickness of the semitransparent films is defined as a×m×?×n, where, ? is the wavelength of the second reproducing signal, and n is the refraction index of the first transparent board. An inequality of 1.0=a=1.3 is satisfied and m is an integer number of 1 or more.</p> |
