TH80184A - Optical Retention and Retrieval Record Media and Recording Method - Google Patents

Abstract

DC60 (02/08/48) A light-dependent storage and retrieval medium consists of, for example, a transmitting substrate, which creates an absorbing layer containing at least one light-absorbing substance on this substrate and a reflective layer made of a metallic film on this absorbing layer, where the optical parameter is denoted by p = nabsdabs/lambda, where nabs is the real part of the complex refractive index of the absorbing layer, dabs is the average thickness of the absorbing layer, and lambda is the wavelength of the laser beam used for reading, i.e., 0.6 < p < 1.6. A light-dependent storage and retrieval medium consists of, for example, a transmitting substrate, which creates an absorbing layer containing at least one light-absorbing substance on this substrate and a reflective layer made of a metallic film on this absorbing layer, where the optical parameter is denoted by p = nabsdabd/lambda, where nabs is the real part of the complex refractive index of the absorbing layer, dabs... ε is the average thickness of the absorption layer and lambda is the wavelength of the laser beam used for reading, i.e., 0.6 < p < 1.6.

Claims (5)

1. An optical recording medium consisting of: i) a transmitting substrate, an absorbing layer containing at least one photoabsorbent material formed on the substrate, and a reflecting layer made of a metal film formed on the absorbing layer, where the imaginary portion at 780 nm of the complex refractive index of the absorbing layer is 0.001 ≤ 0.2 ≤ 0.2, and where the photoabsorbent material in the absorbing layer is at least one cyanine dye represented by the formula (chemical formula), where each A and A' group may be the same or different, i.e., the group of atoms forming the naphthalene ring or the substituted naphthalene ring, b is pentamethylene (-CH=CH-CH=CH-CH=), where each hydrogen atom may be replaced by a halogen atom, an alkyl group, an alkoxy group or a diphenylamino group, or may have a side chain that is Substituted or unsubstituted rings linked by a number of carbon atoms, R1 and R1', may have the same or different groups, i.e., substituted or unsubstituted alkyl, alkoxy, alkylhydroxy, aralkyl, alkenyl, alkylcarboxyl, or alkylsulfonyl groups, or substituted or unsubstituted alkylcarboxyl or alkylsulfonyl groups bonded to... Alkali metal ions or alkyl groups, and X1 is an anion chosen from a group consisting of halogen atoms, perchloric acid, borofluoric acid, benzenesulfonic acid, toluenesulfonic acid, alkylsulfonic acid, benzenecarboxylic acid, alkylcarboxylic acid, or trifluoromethylcarboxylic acid, given that when R1 and R1' are bound to alkali metal ions, X1- may be absent. 2. An optical recording medium as per claim 1, in which the absorbing layer contains cyanine dye alone or in combination with at least one other absorbing material. 3. An optical recording medium as per claim 1, in which the absorbing layer contains indodicarbosianine alone or in combination with at least one other absorbing substance. 4. An optical recording medium as described in claim 1, whose light-transmitting substrate has helical grooves formed on its surface, creating an absorbing layer above it. 5. Method for recording data on an optical recording medium, which uses the optical recording medium as described in claim 1 and records the data by distorting the substrate side of the absorbing layer by irradiating it with a laser beam.