Patents by Inventor Calvin T. Chow

Calvin T. Chow 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).

  • Determination of light absorption pathlength in a vertical-beam photometer
    Patent number: 6339472
    Abstract: Disclosed are photometric methods and devices for determining optical pathlength of liquid samples containing analytes dissolved or suspended in a solvent. The methods and devices rely on determining a relationship between the light absorption properties of the solvent and the optical pathlength of liquid samples containing the solvent. This relationship is used to establish the optical pathlength for samples containing an unknown concentration of analyte but having similar solvent composition. Further disclosed are methods and devices for determining the concentration of analyte in such samples where both the optical pathlength and the concentration of analyte are unknown. The methods and devices rely on separately determining, at different wavelengths of light, light absorption by the solvent and light absorption by the analyte. Light absorption by the analyte, together with the optical pathlength so determined, is used to calculate the concentration of the analyte.
    Type: Grant
    Filed: April 25, 2000
    Date of Patent: January 15, 2002
    Inventors: Dean G. Hafeman, Calvin T. Chow
  • Determination of light absorption pathlength in a vertical-beam photometer
    Patent number: 6320662
    Abstract: Disclosed are photometric methods and devices for determining optical pathlength of liquid samples containing analytes dissolved or suspended in a solvent. The methods and devices rely on determining a relationship between the light absorption properties of the solvent and the optical pathlength of liquid samples containing the solvent. This relationship is used to establish the optical pathlength for samples containing an unknown concentration of analyte but having similar solvent composition. Further disclosed are methods and devices for determining the concentration of analyte in such samples where both the optical pathlength and the concentration of analyte are unknown. The methods and devices rely on separately determining, at different wavelengths of light, light absorption by the solvent and light absorption by the analyte. Light absorption by the analyte, together with the optical pathlength so determined, is used to calculate the concentration of the analyte.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: November 20, 2001
    Assignee: Molecular Devices Corporation
    Inventors: Dean G. Hafeman, Calvin T. Chow
  • Determination of light absorption pathlength in a vertical-beam photometer
    Patent number: 6188476
    Abstract: Disclosed are photometric methods and devices for determining optical pathlength of liquid samples containing analytes dissolved or suspended in a solvent. The methods and devices rely on determining a relationship between the light absorption properties of the solvent and the optical pathlength of liquid samples containing the solvent. This relationship is used to establish the optical pathlength for samples containing an unknown concentration of analyte but having similar solvent composition. Further disclosed are methods and devices for determining the concentration of analyte in such samples where both the optical pathlength and the concentration of analyte are unknown. The methods and devices rely on separately determining, at different wavelengths of light, light absorption by the solvent and light absorption by the analyte. Light absorption by the analyte, together with the optical pathlength so determined, is used to calculate the concentration of the analyte.
    Type: Grant
    Filed: December 23, 1998
    Date of Patent: February 13, 2001
    Assignee: Molecular Devices Corporation
    Inventors: Dean G. Hafeman, Calvin T. Chow
  • Determination of light absorption pathlength in a vertical-beam photometer
    Patent number: 5959738
    Abstract: Disclosed are photometric methods and devices for determining optical pathlength of liquid samples containing analytes dissolved or suspended in a solvent. The methods and devices rely on determining a relationship between the light absorption properties of the solvent and the optical pathlength of liquid samples containing the solvent. This relationship is used to establish the optical pathlength for samples containing an unknown concentration of analyte but having similar solvent composition. Further disclosed are methods and devices for determining the concentration of analyte in such samples where both the optical pathlength and the concentration of analyte are unknown. The methods and devices rely on separately determining, at different wavelengths of light, light absorption by the solvent and light absorption by the analyte. Light absorption by the analyte, together with the optical pathlength so determined, is used to calculate the concentration of the analyte.
    Type: Grant
    Filed: July 1, 1997
    Date of Patent: September 28, 1999
    Assignee: Molecular Devices Corporation
    Inventors: Dean G. Hafeman, Calvin T. Chow