Patents by Inventor Su Y. Liu

Su Y. Liu 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: 5454491
    Abstract: A device for delivering precisely measured, minute quantities of liquid has no metal parts which contact the liquid. The device employs a barrel defining member with a bore which receives a polymer coated glass or ceramic fiber which functions as a piston. Fluid is drawn into and discharged from the bore via a needle in the form of a polymer coated glass or ceramic capillary tube.
    Type: Grant
    Filed: August 30, 1993
    Date of Patent: October 3, 1995
    Assignee: World Precision Instruments, Inc.
    Inventor: Su Y. Liu
  • Patent number: 5444807
    Abstract: The chemical properties of a flowing liquid analyte, the analyte comprising a solvent having an index of refraction which is the same as or closely approaches that of water, are determined by liquid chromatography or capillary electrophoreses wherein the analyte is caused to flow through an optical waveguide. The waveguide is a rigid capillary having a refrctive index of less than 1.33. Measurement light is launched axially into the analyte by inserting an optical fiber, coupled to a light source, into one end of the waveguide.
    Type: Grant
    Filed: May 13, 1994
    Date of Patent: August 22, 1995
    Assignee: World Precision Instruments, Inc.
    Inventor: Su Y. Liu
  • Patent number: 5416879
    Abstract: Water or some other aqueous fluid is employed as the light transmitting medium of a liquid-core fiber-optic wave guide employed as a spectrophotometer cell by employing, to define the core region, a polymer having a refractive index of less than 1.33. The light conducting channel defined by the aqueous fluid filled core may be a capillary or other suitably shaped vessel. The analysis of samples is accomplished by drawing a sample into the wave guide core region throughout the use of a fiber optic piston and thereafter delivering measurement light to the sample via the piston.
    Type: Grant
    Filed: December 17, 1993
    Date of Patent: May 16, 1995
    Assignee: World Precision Instruments, Inc.
    Inventor: Su Y. Liu
  • Patent number: 5294325
    Abstract: Small quantities of liquid are conveyed, either for the purpose of filling micropipettes or to function as an electrolyte in an ion selective electrode, in a flexible non-metallic capillary tube which is mounted, at a first end, in an adapter fitting. The fitting defines a socket for coupling to a source of liquid, a hypodermic syringe for example, or for receiving an electrochemical half-cell which will contact an electrolyte in the tube. A filter may be interposed between the fitting and hypodermic syringe so as to frictionally engage both when the device is employed for filling micropipettes.
    Type: Grant
    Filed: July 9, 1992
    Date of Patent: March 15, 1994
    Assignee: World Precision Instruments, Inc.
    Inventor: Su Y. Liu