摘要:
A first light ray with a wavelength λ1 emanating from the first emission light source passes through the transparent substrate and is condensed by the objective lens on a signal surface of a first optical disk with a substrate thickness t1, a second light ray with a wavelength λ2 (≠λ1) emanating from the second emission light source passes through the transparent substrate and is condensed by the objective lens on a signal surface of a second optical disk with a substrate thickness t2, a step structure of at least one step is formed along a circle or an ellipse on a surface of the transparent substrate, and and by the step of the step structure, a phase of the first light ray is shifted by 2πn1+Δ1 and a phase of the second light ray is shifted by 2πn2+Δ2.
摘要:
An objective lens records information on, or read information from, a first optical medium by utilizing a first light beam which convergences on the first optical medium at a first numerical aperture (hereinafter “NA1”). The objective lens records information on, or read information from, a second optical medium by utilizing a second light beam which convergences on the second optical medium at a second numerical aperture (hereinafter “NA2”). In the objective lens, NA1 is greater than NA2. The objective lens has an optical lens for receiving the first light beam and the second light beam. The optical lens has a peripheral diffraction structure disposed substantially outside an area of incidence of the second light beam for suppressing fluctuation in wavefront aberration of the first light beam, and a phase step structure disposed in a central region relative to the peripheral region for producing a phase difference in the second light beam.
摘要:
An objective lens records information on, or read information from, a first optical medium by utilizing a first light beam which convergences on the first optical medium at a first numerical aperture (hereinafter “NA1”). The objective lens records information on, or read information from, a second optical medium by utilizing a second light beam which convergences on the second optical medium at a second numerical aperture (hereinafter “NA2”). In the objective lens, NA1 is greater than NA2. The objective lens has an optical lens for receiving the first light beam and the second light beam. The optical lens has a peripheral diffraction structure disposed substantially outside an area of incidence of the second light beam for suppressing fluctuation in wavefront aberration of the first light beam, and a phase step structure disposed in a central region relative to the peripheral region for producing a phase difference in the second light beam.
摘要:
A dry cell accommodating device includes a dry cell chamber, a cover and a dry cell holder. When a plurality of larger dry cells, for instance, size "AA" dry cells are accommodated, they are fitted into the interior of the dry cell chamber without any necessity for the dry cell holder. When a plurality of smaller dry cells, for instance, size "AAA" dry cells are accommodated, they are first held by means of the dry cell holder and the latter is then fitted into the dry cell chamber together with the dry cells. The device is provided with a mechanism for inhibiting an occurrence of incorrect fitting of the dry cell holder. The mechanism comprises a plurality of projections on the bottom of the dry cell chamber and a plurality of recesses formed at the lower part of the dry cell holder to be fitted over the projections when the dry cell holder is oriented in the correct direction. Further, the device is provided with another mechanism for inhibiting incorrect fitting of smaller dry cells. The last-mentioned mechanism comprises a pair of projections formed on one side of the dry cell holder and an insulation ring fitted around the outer periphery of the end part of a terminal rod disposed on the other side of the holder.
摘要:
An objective lens is moved with a disc irradiated with laser light. A maximum value FEmax and a minimum value FEmin of the focus error signal, and a maximum value FSmax of the amplitude of a focus sum signal are measured. “(FEmax−FEmin)/FSmax” is compared with a determination value to determine the type of a disc.
摘要:
For improving durability of a wiring harness of a power supply system used in a sliding structure, a power supply system includes a casing; a wiring harness; a harness supporter arranged along a base of the casing so as to move freely back-and-forth in the casing; and a constant force spring arranged along the base of the casing. The wiring harness is bent and wired along an outer surface of the harness supporter, and the harness supporter is biased with a spring force by the constant force spring so as to absorb an extra length of the wiring harness. A winding part of the constant force spring is separated from a harness receiving space of the casing, and an end of the constant force spring led from the winding part is connected and fixed to the harness supporter at an outside of the casing.
摘要:
The present invention provides an optical unit capable of suppressing a thermal influence on the optical element even if a heating source such as a laser driver is disposed near the optical element. A light pickup unit 9 of the present invention includes a beam splitter 12 and a collimate lens 13 at locations opposed to a laser driver 17. In a space 24 formed by the laser driver 17, the beam splitter 12 and the collimate lens 13, a thermal insulation sheet 18 is provided on the side of the laser driver 17, and a thermal conductive sheet 19 is provided on the side of the beam splitter 12 and the collimate lens 13.
摘要:
An objective lens is moved with a disc irradiated with laser light. A maximum value FEmax and a minimum value FEmin of the focus error signal, and a maximum value FSmax of the amplitude of a focus sum signal are measured. “(FEmax−FEmin)/FSmax” is compared with a determination value to determine the type of a disc.
摘要:
In a coupling structure of a wiring member for coupling a plurality of connector terminals with the wiring member which is configured by arranging in parallel a plurality of flat-type conductors in a width direction thereof and covering an outer periphery of the flat-type conductors by an insulation member, the connector terminals are electrically coupled to the wiring member in an orthogonal manner so as to match to terminal pitches of a complementary connector.
摘要:
For improving durability of a wiring harness of a power supply system used in a sliding structure, a power supply system 1 includes a casing 3; a wiring harness 2; a harness supporter 6 arranged so as to move freely back-and-forth in the casing 3; and a constant force spring 22. The wiring harness 2 is bent and wired along an outer surface of the harness supporter, and the harness supporter is biased with a spring force by the constant force spring so as to absorb a service length of the wiring harness. A spring unit 10 winding the constant force spring 22 around is arranged at the harness supporter 6. An end 22a′ of the constant force spring 22 pulled from the spring unit 10 is fixed at the casing 3. The constant force spring 22 is formed by winding a strip steel sheet spirally.