摘要:
An optical disc and its manufacturing method in which humps may be prohibited from being formed on an outer rim area of the disc to assure optimum surface properties of a light transmitting layer of the disc to contribute to further increase in recording capacity. On a substrate 2 of an optical disc 1 are sequentially formed a recording portion 6 and a light transmitting layer 5. The light falls on the light transmitting layer 5 to record and/or reproduce information signals for a signal recording area 6a of the substrate 2. The radial distance D from the outermost rim of the substrate 2 to the signal recording area 6a is selected to be larger than the radial width L of a hump 5a formed on the outer rim of the light transmitting layer 5. The hump 5a has a height h from the surface of the light transmitting layer 5 not larger than 70 &mgr;m.
摘要:
An optical disc and its manufacturing method in which humps may be prohibited from being formed on an outer rim area of the disc to assure optimum surface properties of a light transmitting layer of the disc to contribute to further increase in recording capacity. On a substrate 2 of an optical disc 1 are sequentially formed a recording portion 6 and a light transmitting layer 5. The light falls on the light transmitting layer 5 to record and/or reproduce information signals for a signal recording area 6a of the substrate 2. The radial distance D from the outermost rim of the substrate 2 to the signal recording area 6a is selected to be larger than the radial width L of a hump 5a formed on the outer rim of the light transmitting layer 5. The hump 5a has a height h from the surface of the light transmitting layer 5 not larger than 70 &mgr;m.
摘要:
An optical recording medium capable of recording and/or reproducing an information by using a laser beam, comprising: a support layer having an information signal-recording portion on one side surface thereof on which said laser beam is incident, and a transparent layer disposed over the support layer and having a thickness smaller than that of the support layer. In accordance with the present invention, there are further provided production method for optical or magneto-optical discs whereby a high density reproduction can be achieved.
摘要:
The present invention relates to a multi-layered disc-shaped information recording medium having a plurality of signal recording layers each carrying information signals. In preparing the recording medium, a first substrate obtained on punching a sheet obtained in turn by having a signal recording pattern transcribed on it from a first stamper and by forming a semi-transparent film on a signal surface is bonded to a second substrate obtained on injection molding a synthetic resin material. The second substrate is prepared by having transcribed to it a signal recording pattern formed on a second stamper provided on an injection molding device. A reflective film is formed on a signal surface having the transcribed second substrate. The first and second substrates are bonded together on their signal recording layers by a transparent adherent layer.
摘要:
A multi-layer recording medium including a light-transmitting substrate, a first information recording layer formed on the substrate, an intermediate layer at least part of which is formed of a photo-curable resin film, and which is formed on the first information recording layer, a second information recording layer formed on a surface of the intermediate layer opposite to the surface facing the first information signal layer, and a protective layer formed on the second information signal layer. A method for producing such multi-layer recording medium is also disclosed.
摘要:
Such an optical recording medium is disclosed that includes at least one layer of an information layer (11) for which at least any of an optical recording or reproducing is performed with an optical parameter of N.A. (numerical aperture)/&lgr;(wavelength)≧1.2[&mgr;m−1], and in at least its information signal area, its focus error amount is equal to or less than ±&lgr;/(N.A.)2/8 in a band equal to or more than a focus servo cut-off frequency of an optical recording and reproducing apparatus which performs at least any of the optical recording or reproducing while within ±&lgr;/(N.A.)2/4 when only the reproduction is performed.
摘要:
An optical disc having a light transmitting layer of a reduced uniform thickness. The optical disc has a transparent film bonded via a pressure-sensitive adhesive sheet or a dry photopolymer sheet on a substrate to serve as a light transmitting layer. The signal recording surface is formed on the substrate and/or the transparent film. The light transmitting layer may be constituted solely by a pressure-sensitive adhesive sheet or a dry photopolymer sheet. In the present optical disc, recording and/or reproduction is performed from the light transmitting layer with respect to the signal recording surface. The pressure-sensitive adhesive sheet or the dry photopolymer sheet is itself in a sheet form and is previously formed into a layer (sheet) of a pre-set thickness, in a manner different from the case in which a UV light curable resin is coated on a substrate. The light transmitting layer of an extremely thin film thickness and devoid of sporadic film thickness variations can easily be formed by using the sheet as an adhesive layer or a light transmitting layer itself.
摘要:
A multi-layer recording medium including a light-transmitting substrate, a first information recording layer formed on the substrate, an intermediate layer at least part of which is formed of a photo-curable resin film, and which is formed on the first information recording layer, a second information recording layer formed on a surface of the intermediate layer opposite to the surface facing the first information signal layer, and a protective layer formed on the second information signal layer. A method for producing such multi-layer recording medium is also disclosed.
摘要:
An optical recording medium is provided which achieves a higher recording capacity. This optical recording medium includes a base formed of thermoplastic resin which has a thickness ranging from between approximately 0.3 to 1.2 nm, a guide groove formed on the base, at least a reflective film and a phase-change recording layer successively formed on the guide groove, arid a light transmissive layer having a thickness ranging from between approximately 3 to 177 .mu.m. In this optical recording medium, the unevenness .DELTA.t of the thickness of the light transmission layer is set within the range of:.DELTA.t.ltoreq..+-.5.26(.lambda./N.A..sup.4)(.mu.m)wherein N.A. represents a numerical aperture of an optical head device of the optical disk recording and/or reproducing apparatus and .lambda. represents the wavelength of laser light utilized by the optical disk recording and/or reproducing apparatus.
摘要:
An optical measuring instrument includes: a flow channel for allowing a specimen to be circulated therein; a first light source including a light emitting diode for emitting light to be used for optical adjustment and/or image confirmation in the flow channel; a second light source for irradiating light upon the specimen circulated in the flow channel; and a light detector for detecting the spectrum intensity of the light emitted from the first and second light sources.