DOUGLAS WILLIAM SHEPARD
Pilots at Meadowlark Ln, Santa Barbara, CA

5676830, Oct 14, 1997

Apr 12, 1996

8/632035

Gary R. Janik - Palo Alto CA
Douglas W. Shepard - Santa Barbara CA

Wyatt Technology Corporation - Santa Barbara CA

B01D 1508

2101982

A capillary tube used to transfer a liquid sample into a detection cell following separation by a chromatographic system is modified by plugging or otherwise severely restricting its flow. Near its plugged end, said tube is drilled to provide a plurality of holes or ports perpendicular thereto and penetrating into the central flowing core of said tube so as to direct outflow from the tube perpendicularly therefrom. The outer diameter of this so-modified capillary tube is selected to be of a size comparable to, though smaller than, the detection cell diameter into which it transfers the flowing sample. In this manner, fluid transferred into a detection cell by said modified capillary tube will be split into a plurality of smaller streams flowing outwardly therefrom and striking the adjacent detector cell walls almost immediately. Because of the close proximity of the emerging split streams to the walls of the detection cell, the eddies produced thereby will be very small and the contents of the detection cell will be homogenized rapidly.

6128080, Oct 3, 2000

Jun 6, 1997

8/870937

Gary R. Janik - Palo Alto CA
Douglas W. Shepard - Santa Barbara CA
Steven P. Trainoff - Carpinteria CA
David T. Phillips - Santa Barbara CA

Wyatt Technology Corporation - Santa Barbara CA

G01B 902

356351

A method and apparatus is disclosed for measuring the refractive index difference between a reference and sample liquid based on an interferometric design. The resultant device has an almost unlimited range of operation in contrast to a conventional interferometric refractometer of the so-called polarization type whose dynamic range is restricted to a relatively narrow range of refractive indices. The measurement of the refractive index difference between a sample and reference cell is achieved by measuring the angle through which the plane of polarization of a combined beam has rotated. For the conventional device, this angle is restricted to about. pi. radians which corresponds to a half wavelength shift between the reference and sample components of said combined beam. The extended range device disclosed permits this angle to be tracked and measured accurately over many rotations. The rotation tracking is achieved by one of three embodiments, the preferred of which involves the use of a liquid crystal retarder.

5900152, May 4, 1999

May 12, 1997

8/854442

Gary R. Janik - Palo Alto CA
Douglas W. Shepard - Santa Barbara CA
Steven T. Monser - Santa Barbara CA

Wyatt Technology Corporation - Santa Barbara CA

B01D 1508

210656

A capillary tube used to transfer a liquid sample into a detection cell following separation by a chromatographic system is modified by plugging or otherwise severely restricting its flow. Near its plugged end, said tube is drilled to provide a plurality of holes or ports perpendicular thereto and penetrating to the central flowing core of said tube so as to direct outflow from the tube perpendicularly therefrom. The outer diameter of this somodified capillary tube is selected to be of a size comparable to, though smaller than, the detection cell diameter into which it transfers the flowing sample. In this manner, fluid transferred into a detection cell by said modified capillary tube will be split into a plurality of smaller streams flowing outwardly therefrom and striking the adjacent detector cell walls almost immediately. Because of the close proximity of the emerging split streams to the walls of the detection cell, the eddies produced thereby will be very small and the contents of the detection cell will be homogenized rapidly.