摘要:
A method and an optical disk apparatus that can accurately and stably correct the spherical aberration even for a blank write-once optical disk and can detect a spherical aberration error signal with a simple construction of parts in real time. In a blank write-once disk 20, the tracking servo is switched to an inoperative state, push-pull signals from outputs of the photodetector 12 are detected in a state of “in focus” and in a state of “out focus,” respectively, by a push-pull signal generation circuit 34, and.the amplitudes of these push-pull signals are subjected to difference calculation in a spherical aberration error detector 31 to obtain a spherical aberration error signal A. Then, the spherical aberration is corrected with this spherical aberration error signal A, and subsequently a specific pattern signal is recorded in a trial writing area, this signal is reproduced in the state of “in focus” and in the state of “out focus,” respectively, the amplitude of each reproduced signal is acquired by a reproduced signal generation circuit 32, these amplitudes are subjected to difference calculation in the spherical aberration error detector 31 to obtain a spherical aberration error signal B. The spherical aberration is corrected with this.
摘要:
A rolling bearing comprises an outer ring, an inner ring and rolling elements rotatably disposed between the outer and inner rings. At least a member selected from the outer ring, inner ring and rolling elements has C content of 0.2 or more and 0.6 or less wt %, Cr content of 2.5 or more and 7.0 or less wt %, Mn content of 0.5 or more and 2.0 or less wt %, Si content of 0.1 wt % or more and 1.5 or less wt %, and Mo content of 0.5 or more and 3.0 or less wt %. Further, a carburizing or carbo-nitriding treatment, a quenching treatment and a tempering treatment are applied to the selected member. Furthermore, retained austenite on a surface thereof is 15 % or more and 45 % or less vol. %, and the surface hardness thereof is HRC60 or more.
摘要:
A polyester film for forming which is excellent in formability especially at low temperatures and low pressures and in solvent resistance and heat resistance and is reduced in environmental burden. The polyester film for forming is a biaxially oriented polyester film comprising a copolyester as a component, and is characterize in that (1) the stress at 100% elongation of the film in each of the machine direction and the transverse direction is 10 to 1,000 MPa at 25° C. and is 1 to 100 MPa at 100° C.; (2) the storage viscoelasticity (E′) of the film in each of the machine direction and the transverse direction is 10 to 1,000 MPa at 100° C. and is 5 to 40 MPa at 180° C.; and (3) the degree of heat distortion (initial load, 49 mN) of the film in the machine direction is −3% to +3% at 175° C.
摘要:
A polyester film for forming which is excellent in formability especially at low temperatures and low pressures and in solvent resistance and heat resistance and is reduced in environmental burden. The polyester film for forming is a biaxially oriented polyester film comprising a copolyester as a component, and is characterize in that (1) the stress at 100% elongation of the film in each of the machine direction and the transverse direction is 10 to 1,000 MPa at 25° C. and is 1 to 100 MPa at 100° C.; (2) the storage viscoelasticity (E′) of the film in each of the machine direction and the transverse direction is 10 to 1,000 MPa at 100° C. and is 5 to 40 MPa at 180° C.; and (3) the degree of heat distortion (initial load, 49 mN) of the film in the machine direction is −3% to +3% at 175° C.
摘要:
A rolling bearing has the radius of curvature of the raceway on an inner ring and an outer ring is from not smaller than 50.1% to not greater than 51.9% of the diameter of the balls, and at least one of the compositions of the bearing is obtained by forming an alloy steel having a carbon (C) content of from not smaller than 0.50% to not greater than 0.90%, a chromium (Cr) content of from not smaller than 3.0% to not greater than 15.0%, a manganese (Mn) content of from not smaller than 0.10% to not greater than 2.0%, a silicon (Si) content of from not smaller than 0.10% to not greater than 2.0%, a molybdenum (Mo) content of zero or not greater than 2.0% by weight, and a vanadium (V) content of zero or not greater than 2.0%, by weight.
摘要:
The present invention is a polyester film obtained by blending 10-90 wt % of polyester (A) containing ethylene terephthalate as a main constituent component and 90-10 wt % of crystalline polyester (B) different from this polyester (A), which has a half value width of a recrystallization peak obtained by a differential scanning calorimeter (DSC) by lowering temperature of not more than 0.25. The crystalline polyester (B) is preferably a polyester selected from polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT) and polyethylene 2,6 naphthalate (PEN). According to the polyester of the present invention, a polyester film superior in mechanical characteristic and design property and having high crystallinity, which can be used alone or adhered to a metal sheet and which is free of whitening even when the film is heat treated at near or not lower than the melting point can be obtained, and further, a polyester film having such superior resistance to whitening (design property), which is not easily damaged, can be obtained.
摘要:
N-[N-[3-(2-hydroxy-substituted phenyl)propyl]-L-α-aspartyl]-L-phenylalanine 1-methyl ester derivatives, which are useful as sweeteners, may be conveniently produced by subjecting a 2-hydroxychroman derivative having various substituents on the benzene ring and aspartame to a reductive alkylation reaction. These compounds may be purified by subjecting such a derivative containing one or more impurities to a crystallization step to crystallize the same. Further, there are provided a process for producing dialkoxychroman derivatives useful as intermediates for the production of such aspartame derivatives in the above process, and novel dialkoxychroman derivatives thus produced, which are excellent as the production intermediate.
摘要:
A dichroic mirror of a polarized beam splitter is installed between a mirror and an objective lens as a beam synthesize/split means, in an optical system corresponding to a second dick and an optical system corresponding to a first disk arranged so as to form a two-layer structure. The dimension of the optical head in the width, length, and thickness directions are designed moderately.
摘要:
The dichroic mirror or a polarized beam splitter is installed between a mirror and an objective lens as a beam synthesize/split means, in an optical system corresponding to a second disk and an optical system corresponding to a first disk arranged so as to form a two-layer structure. The dimension of the optical head in the width, length, and thickness directions are designed moderately.
摘要:
A gas barrier film comprising a polyamide film and an inorganic deposited layer laminated thereon, wherein the maximum shrinkage percentage after boiling treatment at 95.degree. C. for 30 minutes is not more than 3.5%. The gas barrier film of the present invention has excellent gas barrier property and water vapor-proof property even after boiling or retort treatment. Hence, the film of the present invention can serve well as a wrapping material for a wide range of objects that require high gas barrier property, such as food, medical products, industrial materials and the like, and has great industrial value.