Patents by Inventor Masahisa Shinoda
Masahisa Shinoda has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 8693295Abstract: When using an optical disc medium that includes pit trains having their widths narrower than a diffraction limit, it is difficult to detect a tracking error signal and take a tracking-servo control while increasing pit density in a direction orthogonal to a pit-train extension direction. Information pit trains are arranged spirally or concentrically and formed in a structure in which their depths are changed periodically at a pitch radially along the optical disc medium, so that the tracking error signal can be obtained by push-pull detection of diffraction light from the structure.Type: GrantFiled: May 22, 2007Date of Patent: April 8, 2014Assignee: Mitsubishi Electric CorporationInventors: Kenya Nakai, Masahisa Shinoda, Nobuo Takeshita
-
Patent number: 8472300Abstract: An optical head device mounted in an optical disc device. The optical head device is provided with a diffractive optical element and a photodetector. The diffractive optical element has: a primary diffraction region at a location on which the positive and negative first-order components and some of the zero-order component of a reflectively diffracted light beam are incident; and secondary diffraction regions at locations on which the rest of the zero-order component but none of the positive or negative first-order components of the reflectively diffracted light beam are incident. A main light-receiving section of the photodetector receives the zero-order component of a transmissively diffracted light beam that has passed through the primary diffraction region and the secondary diffraction regions.Type: GrantFiled: January 17, 2011Date of Patent: June 25, 2013Assignee: Mitsubishi Electric CorporationInventors: Masahisa Shinoda, Hironori Nakahara, Masayuki Omaki, Kenya Nakai, Nobuo Takeshita
-
Publication number: 20120106310Abstract: An optical head device mounted in an optical disc device. The optical head device is provided with a diffractive optical element and a photodetector. The diffractive optical element has: a primary diffraction region at a location on which the positive and negative first-order components and some of the zero-order component of a reflectively diffracted light beam are incident; and secondary diffraction regions at locations on which the rest of the zero-order component but none of the positive or negative first-order components of the reflectively diffracted light beam are incident. A main light-receiving section of the photodetector receives the zero-order component of a transmissively diffracted light beam that has passed through the primary diffraction region and the secondary diffraction regions.Type: ApplicationFiled: January 17, 2011Publication date: May 3, 2012Inventors: Masahisa Shinoda, Hironori Nakahara, Masayuki Omaki, Kenya Nakai, Nobuo Takeshita
-
Patent number: 8134908Abstract: 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.Type: GrantFiled: February 19, 2008Date of Patent: March 13, 2012Assignee: Mitsubishi Electric CorporationInventors: Masahisa Shinoda, Daisuke Matsubara, Kenya Nakai, Hironori Nakahara
-
Patent number: 8077581Abstract: An optical pickup has a semiconductor laser device that can emit laser beams with different wavelengths. A beam splitter and objective lens direct the emitted beam onto a rotating optical disc. Reflected light returns through the objective lens and beam splitter to a photodetector. A pair of liquid crystal elements on the optical path from the optical disc to the photodetector have controllable lens functions acting in different directions to produce an adjustable astigmatic effect that enables the photodetector to generate a focus error signal with a linear range appropriate for the type of optical disc, the number of signal layers in the optical disc, and the spacing between the layers.Type: GrantFiled: February 6, 2009Date of Patent: December 13, 2011Assignee: Mitsubishi Electric CorporationInventor: Masahisa Shinoda
-
Patent number: 8018799Abstract: 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.Type: GrantFiled: September 19, 2006Date of Patent: September 13, 2011Assignee: Mitsubishi Electric CorporationInventors: Daisuke Matsubara, Masahisa Shinoda
-
Patent number: 7848206Abstract: 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.Type: GrantFiled: October 17, 2006Date of Patent: December 7, 2010Assignee: Mitsubishi Electric CorporationInventors: Masahisa Shinoda, Daisuke Matsubara
-
Patent number: 7782730Abstract: 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.Type: GrantFiled: February 15, 2008Date of Patent: August 24, 2010Assignee: Mitsubishi Electric CorporationInventors: Masahisa Shinoda, Daisuke Matsubara, Kenya Nakai, Hironori Nakahara
-
Publication number: 20100097917Abstract: 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.Type: ApplicationFiled: February 19, 2008Publication date: April 22, 2010Inventors: Masahisa Shinoda, Daisuke Matsubara, Kenya Nakai, Hironori Nakahara
-
Patent number: 7652246Abstract: A laser emitting device (9) includes a light emitting portion (4) that emits light of a wavelength ?1 (approximately 405 nm), a light emitting portion (5) that emits light of a wavelength ?2 (approximately 650 nm), and a light emitting portion (6) that emits light of a wavelength ?1 (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 ?1, ?2 and ?3 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).Type: GrantFiled: April 24, 2006Date of Patent: January 26, 2010Assignee: Mitsubishi Electric CorporationInventors: Daisuke Matsubara, Masahisa Shinoda
-
Publication number: 20090303850Abstract: When using an optical disc medium that includes pit trains having their widths narrower than a diffraction limit, it is difficult to detect a tracking error signal and take a tracking-servo control while increasing pit density in a direction orthogonal to a pit-train extension direction. Information pit trains are arranged spirally or concentrically and formed in a structure in which their depths are changed periodically at a pitch radially along the optical disc medium, so that the tracking error signal can be obtained by push-pull detection of diffraction light from the structure.Type: ApplicationFiled: May 22, 2007Publication date: December 10, 2009Applicant: Mitsubishi Electric CorporationInventors: Kenya Nakai, Masahisa Shinoda, Nobuo Takeshita
-
Publication number: 20090201785Abstract: An optical pickup has a semiconductor laser device that can emit laser beams with different wavelengths. A beam splitter and objective lens direct the emitted beam onto a rotating optical disc. Reflected light returns through the objective lens and beam splitter to a photodetector. A pair of liquid crystal elements on the optical path from the optical disc to the photodetector have controllable lens functions acting in different directions to produce an adjustable astigmatic effect that enables the photodetector to generate a focus error signal with a linear range appropriate for the type of optical disc, the number of signal layers in the optical disc, and the spacing between the layers.Type: ApplicationFiled: February 6, 2009Publication date: August 13, 2009Inventor: Masahisa SHINODA
-
Publication number: 20090135701Abstract: [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.Type: ApplicationFiled: September 19, 2006Publication date: May 28, 2009Applicant: Mitsubishi Electric CorporationInventors: Daisuke Matsubara, Masahisa Shinoda
-
Publication number: 20090097121Abstract: 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.Type: ApplicationFiled: October 17, 2006Publication date: April 16, 2009Applicant: Mitsubishi Electric CorporationInventors: Masahisa Shinoda, Daisuke Matsubara
-
Publication number: 20090078857Abstract: A laser emitting device (9) includes a light emitting portion (4) that emits light of a wavelength ?1 (approximately 405 nm), a light emitting portion (5) that emits light of a wavelength ?2 (approximately 650 nm), and a light emitting portion (6) that emits light of a wavelength ?1 (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 ?1, ?2 and ?3 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).Type: ApplicationFiled: April 24, 2006Publication date: March 26, 2009Inventors: Daisuke Matsubara, Masahisa Shinoda
-
Publication number: 20080205235Abstract: 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.Type: ApplicationFiled: February 15, 2008Publication date: August 28, 2008Inventors: Masahisa Shinoda, Daisuke Matsubara, Kenya Nakai, Hironori Nakahara
-
Patent number: 7266072Abstract: A semiconductor laser unit includes a plurality of semiconductor laser elements arranged parallel with one another in a laser beam-emitting direction, and a base for positioning and fixing the plurality of semiconductor laser elements. The plurality of semiconductor laser elements are arranged such that a laser beam emitted from the semiconductor laser element greatest in astigmatism, of the plurality of semiconductor laser elements, is coincident in its axis with a reference axis of the base. In the case that the semiconductor laser unit is arranged on an optical head device, the focusing characteristic on the plurality of laser beams can be improved.Type: GrantFiled: November 1, 2004Date of Patent: September 4, 2007Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Masahisa Shinoda, Kenya Nakai
-
Patent number: 6912192Abstract: A semiconductor laser unit includes a plurality of semiconductor laser elements arranged parallel with one another in a laser beam-emitting direction, and a base for positioning and fixing the plurality of semiconductor laser elements. The plurality of semiconductor laser elements are arranged such that a laser beam emitted from the semiconductor laser element greatest in astigmatism, of the plurality of semiconductor laser elements, is coincident in its axis with a reference axis of the base. In the case that the semiconductor laser unit is arranged on an optical head device, the focusing characteristic on the plurality of laser beams can be improved.Type: GrantFiled: September 11, 2002Date of Patent: June 28, 2005Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Masahisa Shinoda, Kenya Nakai
-
Publication number: 20050094693Abstract: A semiconductor laser unit includes a plurality of semiconductor laser elements arranged parallel with one another in a laser beam-emitting direction, and a base for positioning and fixing the plurality of semiconductor laser elements. The plurality of semiconductor laser elements are arranged such that a laser beam emitted from the semiconductor laser element greatest in astigmatism, of the plurality of semiconductor laser elements, is coincident in its axis with a reference axis of the base. In the case that the semiconductor laser unit is arranged on an optical head device, the focusing characteristic on the plurality of laser beams can be improved.Type: ApplicationFiled: November 1, 2004Publication date: May 5, 2005Inventors: Masahisa Shinoda, Kenya Nakai
-
Publication number: 20030231670Abstract: A semiconductor laser unit includes a plurality of semiconductor laser elements arranged parallel with one another in a laser beam-emitting direction, and a base for positioning and fixing the plurality of semiconductor laser elements. The plurality of semiconductor laser elements are arranged such that a laser beam emitted from the semiconductor laser element greatest in astigmatism, of the plurality of semiconductor laser elements, is coincident in its axis with a reference axis of the base. In the case that the semiconductor laser unit is arranged on an optical head device, the focusing characteristic on the plurality of laser beams can be improved.Type: ApplicationFiled: September 11, 2002Publication date: December 18, 2003Inventors: Masahisa Shinoda, Kenya Nakai