摘要:
An optical pickup device is provided. The optical pickup device includes a first, second, and third light emitting portions emitting light beams having first, second, and third wavelengths, respectively; an adjusting element for optical axes enabled to control the optical axis of the return light beam reflected by the optical recording media after output from the light emitting portion, and a single photo detector receiving the return light beams passing through the adjusting element for optical axes. The first light emitting portion and the second light emitting portion are arranged in such a way that the optical axis of the first light beam and the optical axis of the third light beam approximately coincide with each other. The adjusting element for optical axes controls the axis of the return light beam of said second light beam and the single photo detector receives the return light beams of the first light beam, the second light beam and the third light beam.
摘要:
An optical pickup with a simplified structure in which, according to the type of optical disc, diffracted light from three types of laser light can be directed efficiently onto a photodetector and appropriate focus control can be performed based on the signals detected by the photodetector, and a diffractive optical element that can be used in the optical pickup, which has a semiconductor laser 10 that can emit three types of laser light, a diffractive optical element 42 that diffracts the laser light reflected from the optical disc 31, and a single photodetector 43 that detects the diffracted light exiting the diffractive optical element 42. The diffractive optical element 42 is structured so that 0-order light is the maximal component of the diffracted light generated from each of two of three types of laser light, the two having close wavelengths (with a small wavelength difference), and +1-order light or −1-order light is the maximal component of the diffracted light generated from the remaining one type of laser light.
摘要:
[Problem] An objective is to provide an optical pickup device, for recording on or reproducing from optical medias enable to use for the light beams with plural kind of wavelength, in which plural light beams reflected by the optical medium can be detected by a common photo detector.[Solution Means] An optical pickup device includes a first light emitting portion emitting a first light beam with a first wavelength, a second light emitting portion emitting a second light beam with a second wavelength, a third light emitting portion emitting a third light beam with a third wavelength, an adjusting element for optical axes enable to control the optical axis of the return light beam reflected by the optical recording media after output from the light emitting portion, and a single photo detector receiving the return light beam passing through the adjusting element for optical axes; the first light emitting portion and the second light emitting portion are arranged in such a way that the optical axis of the first light beam and the optical axis of the third light beam approximately coincide with each other; the adjusting element for optical axes controls the axis of the return light beam of said second light beam; and the single photo detector receives the return light beams of the first light beam, the second light beam and the third light beam.
摘要:
An optical-pickup-adjustment optical disk used for adjusting or producing an optical pickup device, includes a transparent protective substrate; and an optical-pickup-adjustment middle-depth information recording layer formed on a side of an inside surface of the transparent protective substrate, wherein the optical-pickup-adjustment middle-depth information recording layer is formed to have a middle depth which is a center of the maximum depth of the maximum-depth information recording layer prescribed by the optical disk standard and the minimum depth of the minimum-depth information recording layer prescribed by the optical disk standard.
摘要:
A diffractive optical element whose two diffraction gratings diffract three different wavelength light beams is provided. The diffractive optical element includes a first diffraction grating and a second diffraction grating that is located opposite the first one, and is configured in such a way that, among three different wavelength incident light beams, the diffraction efficiency in one light beam diffracted on the first diffraction grating is a predetermined value or less, and the diffraction efficiencies in the other two different incident light beams diffracted on the second diffraction grating are predetermined values or less. This arrangement can achieve a diffractive optical element capable of diffracting the three different wavelength light beams in a simple configuration.
摘要:
A diffractive optical element whose two diffraction gratings diffract three different wavelength light beams is provided. The diffractive optical element includes a first diffraction grating and a second diffraction grating that is located opposite the first one, and is configured in such a way that, among three different wavelength incident light beams, the diffraction efficiency in one light beam diffracted on the first diffraction grating is a predetermined value or less, and the diffraction efficiencies in the other two different incident light beams diffracted on the second diffraction grating are predetermined values or less. This arrangement can achieve a diffractive optical element capable of diffracting the three different wavelength light beams in a simple configuration.
摘要:
An optical-pickup-adjustment optical disk used for adjusting or producing an optical pickup device, includes a transparent protective substrate; and an optical-pickup-adjustment middle-depth information recording layer formed on a side of an inside surface of the transparent protective substrate, wherein the optical-pickup-adjustment middle-depth information recording layer is formed to have a middle depth which is a center of the maximum depth of the maximum-depth information recording layer prescribed by the optical disk standard and the minimum depth of the minimum-depth information recording layer prescribed by the optical disk standard.
摘要:
A laser emitting device (9) includes a light emitting portion (4) that emits light of a wavelength λ1 (approximately 405 nm), a light emitting portion (5) that emits light of a wavelength λ2 (approximately 650 nm), and a light emitting portion (6) that emits light of a wavelength λ1 (approximately 780 nm). The light emitting position of the light emitting portion (4) and the light emitting position of the light emitting portion (6) are approximately on the same position as seen in the direction of an optical axis of emitted light of the laser emitting device (9). An optical axis adjusting element (18) is provided for adjusting an optical axis of return light of at least one of the wavelengths among return lights of the wavelengths λ1, λ2 and λ3 so that respective return lights emitted by the light emitting portions (4, 5 and 6) of the laser emitting device (9) and reflected by an optical recording medium (16) are received by a common light detector (20).
摘要:
An optical pickup with a simplified structure in which, according to the type of optical disc, diffracted light from three types of laser light can be directed efficiently onto a photodetector and appropriate focus control can be performed based on the signals detected by the photodetector, and a diffractive optical element that can be used in the optical pickup, which has a semiconductor laser 10 that can emit three types of laser light, a diffractive optical element 42 that diffracts the laser light reflected from the optical disc 31, and a single photodetector 43 that detects the diffracted light exiting the diffractive optical element 42. The diffractive optical element 42 is structured so that 0-order light is the maximal component of the diffracted light generated from each of two of three types of laser light, the two having close wavelengths (with a small wavelength difference), and +1-order light or −1-order light is the maximal component of the diffracted light generated from the remaining one type of laser light.
摘要:
A laser emitting device (9) includes a light emitting portion (4) that emits light of a wavelength λ1 (approximately 405 nm), a light emitting portion (5) that emits light of a wavelength λ2 (approximately 650 nm), and a light emitting portion (6) that emits light of a wavelength λ1 (approximately 780 nm). The light emitting position of the light emitting portion (4) and the light emitting position of the light emitting portion (6) are approximately on the same position as seen in the direction of an optical axis of emitted light of the laser emitting device (9). An optical axis adjusting element (18) is provided for adjusting an optical axis of return light of at least one of the wavelengths among return lights of the wavelengths λ1, λ2 and λ3 so that respective return lights emitted by the light emitting portions (4, 5 and 6) of the laser emitting device (9) and reflected by an optical recording medium (16) are received by a common light detector (20).