Patents by Inventor Eiji Yokoyama
Eiji Yokoyama 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).
-
Publication number: 20110181838Abstract: A projector includes: a plurality of reflection-type light modulation device which modulate a plurality of color light fluxes according to image information; a plurality of reflection-type polarizing plate; a color combining device; a projection lens that projects the combined color light from the color combining device; and a light-transmissive member that transmits a color light flux incident thereon, wherein the light-transmissive member is disposed only in an optical path between a first reflection-type polarizing plate, which is one of the plurality of reflection-type polarizing plate, and the color combining device.Type: ApplicationFiled: January 19, 2011Publication date: July 28, 2011Applicant: SEIKO EPSON CORPORATIONInventors: Eiji YOKOYAMA, Shinichi WAKABAYASHI
-
Patent number: 7661823Abstract: A prism structure that includes: a plurality of liquid crystal devices each include a liquid crystal panel and a light emitting-side optical element, and generate an image light through modulation of any of a plurality of color lights in accordance with image information; and a cross dichroic prism that combines the image lights coming from the liquid crystal devices. In the prism structure, each of the liquid crystal devices further includes: a fixture member that is fixed to the cross dichroic prism; a retention member that keeps hold of the liquid crystal panel, and is fixed to the fixture member; and a light emitting-side optical element retention member that keeps hold of the light emitting-side optical element, and is rotation-adjustable about an illumination axis. The light emitting-side optical element retention member is rotation-adjusted about the illumination axis before fixation to the retention member.Type: GrantFiled: January 23, 2006Date of Patent: February 16, 2010Assignee: Seiko Epson CorporationInventors: Yoshihiro Terada, Takashi Saegusa, Hidetoshi Hashizume, Eiji Yokoyama
-
Publication number: 20090003168Abstract: Means (101a) for evaluating positional control deviation and means (102a) for outputting a corrective signal, this being a set of signals with kick and brake functions, to an actuator (10) on the basis of the evaluation result are provided. Although control deviation may increase due to external shock or vibration acting on the disc device or when a disc having eccentricity, wobble, or another physical deformity is reproduced, the control deviation is suppressed without loss of control stability, and stable recording and reproducing is always possible.Type: ApplicationFiled: September 5, 2007Publication date: January 1, 2009Applicant: Mitsubishi Electric CorporationInventor: Eiji Yokoyama
-
Patent number: 7116611Abstract: The present invention provides a control system of following a follow target position. A control system has a disturbance observer for obtaining a disturbance force estimation value and a speed estimation value as estimation values of a disturbance force and a speed as a speed to be controlled by using an actuator control signal cont and a zero follow position which can be observed. Since the disturbance force estimation value and speed estimation value are fed back.Type: GrantFiled: August 27, 2002Date of Patent: October 3, 2006Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Eiji Yokoyama
-
Publication number: 20060209265Abstract: A prism structure that includes: a plurality of liquid crystal devices each include a liquid crystal panel and a light emitting-side optical element, and generate an image light through modulation of any of a plurality of color lights in accordance with image information; and a cross dichroic prism that combines the image lights coming from the liquid crystal devices. In the prism structure, each of the liquid crystal devices further includes: a fixture member that is fixed to the cross dichroic prism; a retention member that keeps hold of the liquid crystal panel, and is fixed to the fixture member; and a light emitting-side optical element retention member that keeps hold of the light emitting-side optical element, and is rotation-adjustable about an illumination axis. The light emitting-side optical element retention member is rotation-adjusted about the illumination axis before fixation to the retention member.Type: ApplicationFiled: January 23, 2006Publication date: September 21, 2006Applicant: Seiko Epson CorporationInventors: Yoshihiro Terada, Takashi Saegusa, Hidetoshi Hashizume, Eiji Yokoyama
-
Publication number: 20060002266Abstract: A disk physical strain correction signal generator outputs a signal obtained by allowing a phase compensation signal to pass a LPF as a disk physical strain correction signal during a normal period. During a defect detection period, it outputs the output signal of the LPF sampled at the time of the defect detection start as the disk physical strain correction signal. A disturbance pulse correction signal is output based upon a disturbance pulse obtained by subtracting the disk physical strain correction signal from the phase compensation signal. The disk physical strain correction signal and the disturbance pulse correction signal are added to output a defect compensation signal. This defect compensation signal is applied as an actuator control signal during the defect detection period. Thus, it is possible to provide an optical disk device which can carry out a stable driving control for a reproducing operation, etc.Type: ApplicationFiled: June 29, 2005Publication date: January 5, 2006Inventors: Eiji Yokoyama, Tomoaki Ryu
-
Patent number: 6947359Abstract: A disk physical strain correction signal generator outputs a signal obtained by allowing a phase compensation signal to pass a LPF as a disk physical strain correction signal during a normal period. During a defect detection period, it outputs the output signal of the LPF sampled at the time of the defect detection start as the disk physical strain correction signal. A disturbance pulse correction signal is output based upon a disturbance pulse obtained by subtracting the disk physical strain correction signal from the phase compensation signal. The disk physical strain correction signal and the disturbance pulse correction signal are added to output a defect compensation signal. This defect compensation signal is applied as an actuator control signal during the defect detection period. Thus, it is possible to provide an optical disk device which can carry out a stable driving control for a reproducing operation, etc.Type: GrantFiled: February 16, 2001Date of Patent: September 20, 2005Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Eiji Yokoyama, Tomoaki Ryu
-
Patent number: 6724503Abstract: An image sensor according to the present invention includes a casing (4), a light source disposed in the casing (4) for emitting light toward an object (K) to be read, and an image sensor board (6) provided, on an obverse surface thereof, with a plurality of light receiving elements (52) for generating image signals upon receiving light reflected by the object (K). The image sensor board (6) is disposed so that the obverse surface thereof is directed inwardly of the casing (4). The substrate (6) is provided with a light shielding layer (61) for covering the reverse surface of the substrate at least entirely over a portion of the obverse surface where the plurality of light receiving elements (52) are mounted, so that disturbing external light is prevented from entering inside the casing (4).Type: GrantFiled: February 22, 2000Date of Patent: April 20, 2004Assignee: Rohm Co., Ltd.Inventors: Teruhisa Sako, Hiroaki Hayashi, Eiji Yokoyama
-
Patent number: 6654218Abstract: A circuit board (1) is provided upon which a predetermined number of semiconductor elements (5a, 5b, 6), including at least a field-effect transistor for charge and discharge, are mounted. A predetermined number of passive elements (7, 8a˜8c, 9a˜9g) are also mounted onto the circuit board. The semiconductor elements (5a, 5b, 6) are mounted facedown as bare chips on the circuit board (1).Type: GrantFiled: September 21, 2001Date of Patent: November 25, 2003Assignee: Rohm Co., Ltd.Inventors: Eiji Yokoyama, Keigo Nakamura, Naoya Tanaka
-
Publication number: 20030058768Abstract: The present invention provides a control system of following a follow target position. A control system has a disturbance observer for obtaining a disturbance force estimation value and a speed estimation value as estimation values of a disturbance force and a speed as a speed to be controlled by using an actuator control signal cont and a zero follow position which can be observed. Since the disturbance force estimation value and speed estimation value are fed back.Type: ApplicationFiled: August 27, 2002Publication date: March 27, 2003Inventor: Eiji Yokoyama
-
Patent number: 6489757Abstract: A photocoupler includes a signal relay unit, a voltage regulation unit and a signal amplification unit. The signal relay unit transmits an optical signal from the primary side to the secondary side. The voltage regulation unit applies only a safe voltage to the signal relay unit. The voltage regulation unit has a greater withstand voltage than the signal relay unit has. The signal amplification unit amplifies signals sent from the signal relay unit. The withstand voltage of the signal amplification unit is also greater than that of the signal relay unit.Type: GrantFiled: October 17, 2001Date of Patent: December 3, 2002Assignee: Rohm Co., Ltd.Inventors: Masaaki Ogata, Eiji Yokoyama
-
Patent number: 6469724Abstract: The thermal printhead (1) includes an insulating substrate (2), a heating resister (5) formed on the substrate (2), a first glass coat layer (7) formed on the substrate (2) for covering the heating resister (5), and a second glass coat layer (8) formed on the first glass coat layer (7). The heating resister (5) has a centerline average roughness not greater than 0.3 &mgr;m. The first glass coat layer (7) has a centerline average roughness not greater than 0.1 &mgr;m.Type: GrantFiled: April 19, 2001Date of Patent: October 22, 2002Assignee: Rohm Co., Ltd.Inventors: Hiroaki Hayashi, Eiji Yokoyama, Takumi Yamade
-
Patent number: 6448993Abstract: A thermal printhead includes a head substrate (1), a heating resistor (5) provided on the head substrate, a plurality of individual electrodes (2) connected to the heating resistor, and a common electrode (3) connected to the heating resistor. The thermal printhead is further provided with a first coating layer (6) covering the heating resistor, the individual electrodes and the common electrode, and a second coating layer (7) which is formed on the first coating layer and made of sialon containing a conductive material as an additive. The first coating layer is formed with at least one through-hole (6a) or notch (6a′), so that the second coating layer is electrically connected to the common electrode via the through-hole or the notch.Type: GrantFiled: December 30, 1999Date of Patent: September 10, 2002Assignee: Rohm Co., Ltd.Inventors: Hiroaki Hayashi, Eiji Yokoyama, Takumi Yamade
-
Patent number: 6424367Abstract: A thick-film thermal printhead comprises: an oblong rectangular substrate (1) having at least one longitudinal edge (1a); a partial glaze layer provided on the substrate along the longitudinal edge; a linear heating resistor (11) formed on the partial glaze layer; a common electrode (12) formed on the substrate and electrically connected to the heating resistor; and a plurality of individual electrode (13) formed on the substrate and electrically connected to the heating resistor. The common electrode includes a plurality of comb-like teeth (12A). Each of the comb-like teeth includes a tip portion (12c) having a smaller width and a base portion (12d) having a larger width. Each of the individual electrodes includes a tip portion (13d) having a smaller width and an intermediate portion (13e) having a larger width.Type: GrantFiled: November 6, 2000Date of Patent: July 23, 2002Assignee: Rohm Co., Ltd.Inventors: Shinobu Obata, Eiji Yokoyama
-
Publication number: 20020043967Abstract: A photocoupler includes a signal relay unit, a voltage regulation unit and a signal amplification unit. The signal relay unit transmits an optical signal from the primary side to the secondary side. The voltage regulation unit applies only a safe voltage to the signal relay unit. The voltage regulation unit has a greater withstand voltage than the signal relay unit has. The signal amplification unit amplifies signals sent from the signal relay unit. The withstand voltage of the signal amplification unit is also greater than that of the signal relay unit.Type: ApplicationFiled: October 17, 2001Publication date: April 18, 2002Inventors: Masaaki Ogata, Eiji Yokoyama
-
Patent number: 6304280Abstract: A thermal printhead 1 according to the present invention includes a multiplicity of heating elements 4a formed in a row on an obverse surface of an elongated substrate 2 at a portion which is offset widthwise toward one longitudinal side of the substrate, and a protective film 8 formed on the obverse surface of the substrate 2 at the widthwise offset portion for covering the heating elements 4a. The protective film 8 is formed to extend on the obverse surface of the substrate 2 continuously from the widthwise offset portion onto one longitudinal side surface 2a of the substrate. A longitudinal edge 8b of the protective film 8 directed toward the other longitudinal side of the substrate 2 is tapered.Type: GrantFiled: May 1, 2000Date of Patent: October 16, 2001Assignee: Rohm Co., Ltd.Inventors: Takumi Yamade, Hiroaki Hayashi, Eiji Yokoyama
-
Publication number: 20010021148Abstract: A disk physical strain correction signal generation means (11) outputs a signal obtained by allowing a phase compensation signal (S8) to pass a LPF as a disk physical strain correction signal (S11) during a normal period. During a defect detection period, it outputs the output signal of the LPF sampled at the time of the defect detection start as the disk physical strain correction signal (S11). The disturbance pulse detection means (13a) outputs a disturbance pulse correction signal (S13) based upon a disturbance pulse (S13a) obtained by subtracting the disk physical strain correction signal (S11) from the phase compensation signal (S8). The addition means (12) adds the disk physical strain correction signal (S11) and the disturbance pulse correction signal (S13) to output a defect compensation signal (S12). This defect compensation signal (S12) is applied as an actuator control signal (S20) during the detect detection period.Type: ApplicationFiled: February 16, 2001Publication date: September 13, 2001Inventors: Eiji Yokoyama, Tomoaki Ryu
-
Patent number: 6236422Abstract: A protective cover (9) is provided which is used for a thermal printhead including a heat sink plate (1) formed with a plurality of fixing holes (10), a head substrate (2), and a circuit board (3). The heat sink plate (1) is formed with a groove (1a) which divides the upper surface of the heat sink plate (1) into a first region (1b) and a second region (1c). The head substrate (2) is provided with a heating resistor (4) and drive ICs (5). The drive ICs (5) are covered with a coating resin layer (6). The circuit board (3) is formed with through-holes (11). The protective cover (9) includes a main body (9a) having an obverse surface and a reverse surface, and a plurality of pins (12) extending from the reverse surface. Each of the pins (12) is formed with a slit (12a), which facilitates press-fitting of the pin (12) into a respective one of the fixing holes (10).Type: GrantFiled: July 25, 2000Date of Patent: May 22, 2001Assignee: Rohm Co., Ltd.Inventors: Takaya Nagahata, Yasuhiro Yoshikawa, Eiji Yokoyama
-
Patent number: 5986984Abstract: The reference character 5 denotes a supporting shaft holding base, which holds the lower end of a supporting shaft 103 coated with fluororesin with a small frictional coefficient. The reference characters 107a and 107b are tracking magnets bipolar-magnetized in the right and left direction, which are fixed to a fixing base 1 by bonding. The character 108 denotes a mirror for reflecting a light beam 2 incident from the front in the vertical upward direction. The character 6 denotes a lens holder formed of a plastic material, or the like, with light weight and high stiffness, which holds objective lenses 3 and 4 corresponding to a plurality of optical information recording media with different substrate thicknesses and different recording densities at positions eccentrically displaced by almost equal distances from the supporting shaft 103.Type: GrantFiled: February 9, 1996Date of Patent: November 16, 1999Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Keiji Nakamura, Masahisa Shinoda, Takeshi Utakouji, Norihiro Watanabe, Nobuo Takeshita, Hideaki Kobachi, Masaharu Ogawa, Eiji Yokoyama, Kouichi Komawaki, Kenjiro Kime
-
Patent number: 5947402Abstract: A magnetic recording and reproducing apparatus for recording a desired sound or picture signal to a magnetic tape by a magnetic head. At the time of normal-speed recording and reproduction, the magnetic tape is taken up at a constant speed, but by changing the tape travelling speed of the tape on the rotary drum, DTF control and high-speed noiseless reproduction are enabled. The tension of the tape on the entrance side of the rotary drum is controlled to a desired value. This apparatus includes a tape tension actuator and a tape drawing actuator on the entrance side and on the exit side, respectively, of the rotary drum. In DTF control, both tape actuators correct a tracking error of the tape in cooperation with each other. In high-speed noiseless reproduction, both tape actuators are differentially driven so as to lower the tape travelling speed on the rotary drum. Both tape actuators are driven in feedback control using the modern control.Type: GrantFiled: July 23, 1997Date of Patent: September 7, 1999Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Eiji Yokoyama, Masato Nagasawa, Kazuo Mori, Seiji Kishikawa, Masami Tomita, Nobuzumi Kurihara