Patents by Inventor James C. Chen

James C. Chen 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: 5876427
    Abstract: A flexible probe constructed using a flexible circuit having a small cross-sectional profile. In the various disclosed embodiments of the flexible circuit, a flexible substrate includes a plurality of conductive traces that extend along opposite surfaces of the substrate. Light emitting devices (or other electronic devices) are mounted at spaced-apart intervals along the length of the conductive traces using a conductive adhesive/solder. A conductor couples a terminal on the outwardly facing side of each of the light emitting devices to the conductive trace that is disposed on the opposite side of the substrate. In one embodiment, this conductor comprises a short conductive bar that extends between the terminals of pairs of the light emitting devices that are mounted on opposite sides of the flexible substrate so that the pair of light emitting devices are connected in series.
    Type: Grant
    Filed: January 29, 1997
    Date of Patent: March 2, 1999
    Assignee: Light Sciences Limited Partnership
    Inventors: James C. Chen, Brent Wiscombe
  • Patent number: 5865840
    Abstract: The efficacy of a plurality of PDT treatments following at least an initial PDT treatment is enhanced by increasing the neutrophil count of the patient substantially above a normal level. The increase in the neutrophil count leads to a more rapid removal of dead abnormal cells and stroma that have been destroyed, thereby enabling light administered in subsequent PDT treatments to more effectively reach and destroy still living abnormal cells on the surface of the tumor. The accelerated removal of dead tumor cells also enables a more accurate assessment of the treatment progress, since the actual tumor size should be more evident in image of the site. By enabling a tumor to be more rapidly destroyed by multiple PDT treatments, the risk of metastatic spread of abnormal cells away from the treatment site is also reduced.
    Type: Grant
    Filed: October 22, 1997
    Date of Patent: February 2, 1999
    Assignee: Light Sciences Limited Partnership
    Inventor: James C. Chen
  • Patent number: 5827186
    Abstract: An implantable probe having a non-metallic insulating base, non-metallic conductive traces supported by the base, and a plurality of non-metallic light sources supported by the base and coupled to the conductive traces. The conductive traces and the light sources are fabricated from a conductive polymer, which does not cause any artifacts if the implantable probe is left at the treatment site while it is imaged. Further, the implantable probe includes an envelope that is transparent and hermetically encloses the base, the pair of conductive traces, and the light sources. At least a portion of the envelope is optically transparent, enabling light emitted by the light sources to illuminate an adjacent treatment site. The conductive traces and the base are substantially flexible, enabling the probe to be flexed without breaking when the implantable probe is advanced within the body to the treatment site.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: October 27, 1998
    Assignee: Light Sciences Limited Partnership
    Inventors: James C. Chen, Brent Wiscombe
  • Patent number: 5814008
    Abstract: A method and apparatus for applying beat to a treatment site prior to effecting photodynamic therapy. The perfusion of a drug into abnormal tissue in a tumor (12) is enhanced by heating the treatment site at which the tumor is disposed using a heat source (26) mounted on a fixture (20, 34) separate from a light source (28) on a probe used to effect the photodynamic therapy. Alternatively, the heat source and light source may comprise different types of light emitting diodes (LEDs) arranged in an array on a probe (14) disposed at the treatment site. Also mounted on the fixture is a temperature sensor (30), which produces a signal indicative of the temperature at the treatment site. In response to this signal, a controller (24/36) controls the heat source to prevent vascular damage. In addition to enhancing the perfusion of a photoreactive agent into the treatment site, heating the tissue at the site prior to initiating the PDT greatly enhances the efficacy of this treatment.
    Type: Grant
    Filed: July 29, 1996
    Date of Patent: September 29, 1998
    Assignee: Light Sciences Limited Partnership
    Inventors: James C. Chen, Brent Wiscombe
  • Patent number: 5800478
    Abstract: A plurality of embodiments for a flexible probe used to provide photodynamic therapy (PDT) and to effect other medical procedures at an internal treatment site inside a patient's body. Each of the embodiments of the flexible probe (100, 108, 130, 158, 182, 190, 220, 280, 370, 390, 440, 460, 520) includes a flexible substrate (102, 184, 196, 222, 250, 282, 412, 462, 482, 502, 522) on which are disposed conductive traces (414, 466, 468, 488, 490, 504, 506, 524, 526) electrically connected to leads through which electrical current and signals are conveyed. A plurality of light sources (104, 192, 256, 286, 418, 436, 470, 492, 508, 542) or other micro-electronic circuits are connected to the conductive traces and mounted on the flexible substrate. Each of the embodiments of the flexible probes is enclosed within a transparent, biocompatible polymer envelope (106, 110, 464, 522).
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: September 1, 1998
    Assignee: Light Sciences Limited Partnership
    Inventors: James C. Chen, Brent Wiscombe
  • Patent number: 5782896
    Abstract: An implantable probe having an elongated sheath with provision for remotely positioning a device disposed within the elongated sheath. In one embodiment, the device is a circuit board, and a shape memory alloy (SMA) such as Nitinol is used to fabricate one or more actuators that are coupled to the circuit board. The shape memory effect exhibited by the SMA actuator is thermally activated. Electrical current is selectively applied to the actuator to resistively heat the SMA to a temperature sufficient to change its shape. When the shape of the SMA changes, the actuator moves the circuit board or other device longitudinally within the elongated sheath so that the light emitted is directed to a different portion of a treatment site. In another embodiment, the circuit board is rotated about its longitudinal axis within the sheath.
    Type: Grant
    Filed: January 29, 1997
    Date of Patent: July 21, 1998
    Assignee: Light Sciences Limited Partnership
    Inventors: James C. Chen, Brent Wiscombe
  • Patent number: 5766234
    Abstract: A plurality of embodiments for a flexible probe used to provide photodynamic therapy (PDT) and to effect other medical procedures at an internal treatment site inside a patient's body. Each of the embodiments of the flexible probe (100, 108, 130, 158, 182, 190, 220, 280, 370, 390, 440, 460, 520) includes a flexible substrate (102, 184, 196, 222, 250, 282, 412, 462, 482, 502, 522) on which are disposed conductive traces (414, 466, 468, 488, 490, 504, 506, 524, 526) electrically connected to leads through which electrical current and signals are conveyed. A plurality of light sources (104, 192, 256, 286, 418, 436, 470, 492, 508, 542) or other micro-electronic circuits are connected to the conductive traces and mounted on the flexible substrate. Each of the embodiments of the flexible probes is enclosed within a transparent, biocompatible polymer envelope (106, 110, 464, 522).
    Type: Grant
    Filed: April 16, 1996
    Date of Patent: June 16, 1998
    Assignee: Light Sciences Limited Partnership
    Inventors: James C. Chen, Brent Wiscombe
  • Patent number: 5741316
    Abstract: Several embodiments of relatively compact transmitter coils and receiver coils having an improved transcutaneous power transfer efficiency. The transmitter coils are preferably applied to the outer surface of a cutaneous layer on a patient's body and held in place using adhesive tape or other appropriate supporting material. Implanted within the patient's body is a receiver coil. To improve the power transfer efficiency of one embodiment, a transmitter coil and receiver coil include cores having pole faces with a substantially larger area than the cross section of the core at other locations. In addition, the core of the receiver coil is substantially shorter than that of the transmitter coil so that the lines of flux produced by the transmitter coil tend to pass through the pole faces of the receiver coil in greater density than they would if the pole faces of the transmitter and receiver cores were spaced identically.
    Type: Grant
    Filed: December 2, 1996
    Date of Patent: April 21, 1998
    Assignee: Light Sciences Limited Partnership
    Inventors: James C. Chen, Brian D. Wilkerson, Darrin Huston, David J. Brown
  • Patent number: 5715837
    Abstract: A method and apparatus for enhancing transcutaneous energy transfer to provide power to a medical device that is disposed within the body of a patient. A magnetic field is created by an external transmitting coil (200), which induces an electrical current in a receiving coil (300) that has been placed under the patient's skin (100). The flux path magnetic permeability between the receiving and transmitting coils is enhanced by the implantation of particles (120) into dermis (104) within the skin at that site. The particles, which comprise soft iron or other material having a characteristic high magnetic permeability, are preferably implanted using either a hypodermic needle (150) or a medical air injection device (160). A biocompatible material such as Teflon.TM. is applied as a coating (123) to the particles. To implant the particles, they are preferably first suspended in a liquid, forming a mixture that is readily delivered to the desired location.
    Type: Grant
    Filed: August 29, 1996
    Date of Patent: February 10, 1998
    Assignee: Light Sciences Limited Partnership
    Inventor: James C. Chen
  • Patent number: 5702432
    Abstract: A method and apparatus for administering intracorporeal photopheresis to blood flowing in a patient's body to destroy an undesirable component in the blood, where the undesirable component has absorbed a photoreactive agent having a characteristic light absorption waveband. The apparatus includes an implantable housing that is adapted to be placed transcutaneously within a patient's body. An inlet and outlet for a fluid path through the housing are provided and are coupled to a patient's circulatory system so that they convey blood into and out of the housing. Light sources disposed within the housing(or externally disposed and coupled to the housing by optical fibers) emit light having a waveband substantially equal to the absorption waveband of the photoreactive agent. A portion of the fluid path within the housing is optically transparent so that blood is irradiated with light from the light source.
    Type: Grant
    Filed: October 3, 1996
    Date of Patent: December 30, 1997
    Assignee: Light Sciences Limited Partnership
    Inventors: James C. Chen, Brent Wiscombe
  • Patent number: 5634109
    Abstract: The present system may be utilized to minimize access performance penalties in memory subsystems which utilize redundant arrays of disk memory devices. Redundant arrays of disk memory devices provide levels of reliability which are not available with single storage devices; however, the redundancy carries with it an access performance degradation due to the requirement that such systems write data segments and parity elements to the array each time an application updates data within the system. A large nonvolatile cache is therefore provided in association with a redundant array of disk memory devices. Each time a data segment is written or read the data segment is staged from the array to the nonvolatile cache, if the data segment is not already within the cache. Additionally, if the operation is an update, a parity element associated with the data segment to be updated is also staged to the cache with the existing data segment content.
    Type: Grant
    Filed: June 20, 1994
    Date of Patent: May 27, 1997
    Assignee: International Business Machines Corporation
    Inventors: James C. Chen, Joseph S. Glider, Lloyd R. Shipman, Jr., Jesse I. Stamness
  • Patent number: 5571152
    Abstract: A plurality of microminiature light sources (10, 10') are injected at a treatment site to effect photodynamic therapy (PDT). Each of the microminiature light source beads includes an LED chip (12), a rectifier chip (14), and a plurality of electromagnetic receivers (18, 18') encapsulated within a biocompatible, light transmitting material such as silicone, forming a spherical bead that is only a few millimeters in diameter. The light source beads are sufficiently small so that they can be injected into a treatment site such as a tumor (46) from a syringe (58) through a needle (60). A photoreactive agent, which can serve as a carrier fluid for the microminiature light source beads, sensitizes the tissue at the treatment site so that light emitted by the LED chip when energized with an external electromagnetic transmitter (34) kills the tissue or other pathogens at the treatment site that have absorbed the photoreactive agent.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: November 5, 1996
    Assignee: Light Sciences Limited Partnership
    Inventors: James C. Chen, Brian D. Swanson
  • Patent number: 5445608
    Abstract: Light developed by an implantable probe is used to illuminate a treatment site that has been perfused with a photoreactive agent. A number of different embodiments of implantable probes are disclosed. Preferably, an array of light emitting diodes (LEDs) or solid-state laser diodes (LDs) are mounted on a light bar inside the implantable probe and are energized either using a storage battery power source, an inductively coupled external transformer, or with current provided in leads running through a flexible catheter that extends outside the patient's body to an external source. The implantable probe is normally intended to be disposed inside a patient's body during a surgical procedure, at a treatment site, and left in place for several days (or longer) after an incision is closed, while light produced by the array of LEDs or solid-state LDs irradiates the treatment site.
    Type: Grant
    Filed: August 16, 1993
    Date of Patent: August 29, 1995
    Assignee: James C. Chen
    Inventors: James C. Chen, Elric W. Saaski
  • Patent number: 4914644
    Abstract: A disk file digital servo control system utilizes a state estimator wherein the voice coil motor (VCM) current is modeled, rather than measured, thereby eliminating the need for analog-to-digital conversion of the actual VCM current. The VCM current is fed back directly to the input to the power amplifier where it is summed with the control signal output. This effectively changes the integrating power amplifier into a low pass filtering power amplifier, with linear input-output characteristics. Thus, during track following or short seeks, the VCM current is estimated based on this linear model. During long seeks, when the power amplifier is saturated, the VCM current is modeled based upon the known VCM characteristics during saturation, which include the effects of the back electromotive force and the coil current rise time. The microprocessor in the digital servo control system determines which VCM current model to use by a determination of when the power amplifier is in saturation.
    Type: Grant
    Filed: September 26, 1988
    Date of Patent: April 3, 1990
    Assignee: International Business Machines Corporation
    Inventors: James C. Chen, Shih-Ming Shih, Mantle M. Yu
  • Patent number: 4876211
    Abstract: A process for fabricating varactor diodes using ion implantation techniques is described herein. Three successive implanations of N-type ions into a GaAs semi-insulating substrate provide a deep N.sup.+ type conductivity layer about 2-3 microns below the front major surface with concentration of at least 2.times.10.sup.18 ions/cm.sup.3. A fourth implantation of N type ions forms an N type conductivity layer over the N.sup.+ layer. An implanation of P type ions forms the P type conductivity layer over the N type conducitivity layer. A single rapid thermal anneal is performed on the substrate to remove damage to the crystal structure and to electrically activate the implants. The basic doped layered semiconductor structure is thereby produced using ion implantation. This ion implantation process provides a method for fabricating monolithic diode devices reliably and in mass quantities, which can be integrated with other monolithic devices.
    Type: Grant
    Filed: August 9, 1988
    Date of Patent: October 24, 1989
    Assignee: Hughes Aircraft Company
    Inventors: Hilda Kanber, James C. Chen
  • Patent number: 4800420
    Abstract: A two-terminal semiconductor diode device and method for manufacturing the same is disclosed. The semiconductor diode geometry is defined by mesa etching. An ohmic contact is disposed on the flat topped summit of the mesa and another ohmic contact in the shape of a ring is disposed on the bottom layer of the diode. A dielectric layer disposed over the diode has a via hole therethrough to make external contact to a metallic heat sink and ground. A substrate layer supports the semiconductor diode and has a second offset via hole therethrough to the ring contact for external circuit contact and biasing of the diode.The offset via hole simplifies the manufacturing process. Additionally, the active area of the diode makes direct contact to the heat sink improving heat transfer from the device.
    Type: Grant
    Filed: May 14, 1987
    Date of Patent: January 24, 1989
    Assignee: Hughes Aircraft Company
    Inventors: James C. Chen, Wah S. Wong, Cheng K. Pao
  • Patent number: 4778084
    Abstract: A toothpaste discharger comprises a container having a projected mouth at the lower portion and a socket behind the mouth, the socket being bored two holes at two side walls of the socket and an aperture at the top wall thereof, a washer inserted within the container, the washer being provided with an aperture approximately at the center thereof, and a driving means comprising a driving arm, a toothbrush receiving portion integrally under the driving arm, a pin at the top of the driving arm the pin extending with two flanges thereof within two holes of the socket, an elastic connecting portion in front of the pin, a driving rod connected onto the elastic connecting portion by means of a plug to extend into the container, a resilient element behind the pin to bias against the back portion of the socket, and a tongue portion pivoted on the driving arm to close the projected mouth in normal position.
    Type: Grant
    Filed: November 20, 1986
    Date of Patent: October 18, 1988
    Inventors: James C. Chen, Ching-Hua Chen
  • Patent number: 3933588
    Abstract: Upon storage, the activity of immobilized enzymes slowly decreases in the presence of moisture. This decrease in activity can be reduced by a significant extent by treating the immobilized enzymes in the presence of moisture with a long chain quaternary ammonium compound.
    Type: Grant
    Filed: August 23, 1974
    Date of Patent: January 20, 1976
    Assignee: Standard Brands Incorporated
    Inventors: Robert G. Dworschack, William H. White, James C. Chen