Flow cytometry apparatus with improved light beam adjustment

• US 4,989,977 A
• Filed: 07/29/1985
• Issued: 02/05/1991
• Est. Priority Date: 07/29/1985
• Status: Expired due to Term

• Current Assignee: Becton, Dickinson & Co
• Original Assignee: Becton, Dickinson & Co
• Inventors: North, Howard L. Jr.
• Primary Examiner(s): Rosenberger, Richard A.
• Application Number:
  US06/760,205
• Time in Patent Office: 2,017 Days
• Field of Search: 356/343, 356/338, 356/399, 380/484
• US Class Current: 356/338
• CPC Class Codes: G01N 15/1434 Optical arrangements
• CPC Class Codes: G01N 15/149 specially adapted for sorting particles, e.g. by their size or optical properties
• CPC Class Codes: G01N 2015/1452 Adjustment of focus; Alignment

Abstract

A flow cytometry apparatus for determining one or more characteristics of particles or the like flowing in a liquid stream includes a nozzle for generating a liquid flow stream for moving particles therethrough substantially one at a time. A light source provides a beam of focused light to illuminate the particles moving in the stream. A beam steering member is positioned to adjust the focal point of the light beam on the particles by refracting the light beam to cause a displacement of the focal point. At least one detector is provided for detecting light and for associating that light with one or more characteristics of each particle.

Claims

1. A flow cytometry apparatus for determining characteristics of cells flowing in a liquid stream comprising:

means for moving cells, substantially one at a time, in a liquid flow stream;

a light source for providing a beam of illumination directed at the cells in said flow stream;

a focusing lens positioned in the optical path of said light beam to focus said light beam on said cells flowing in the flow stream;

a light beam steering member angularly positioned in the optical path between said lens and said flow stream for refracting the focused light beam to cause a displacement of the focal point of said beam on said stream, said steering member being a light transmissive plate to thereby obtain an adjustment of said focused light beam;

means for detecting light associated with each moving cell as said cell passes through said adjusted, focused light beam; and

means for using said detected light to determine one or more characteristics of said cells.

2. The apparatus of claim 1 wherein said plate is substantially flat and has a thickness between 0.25 and 1.00 mm.

3. The apparatus of claim 1 wherein said plate has a refractive index between 1.50 and 1.55.

4. The apparatus of claim 3 wherein said plate is made of glass.

5. A flow cytometry apparatus for determining characteristics of cells flowing in a liquid stream comprising:

means for moving cells, substantially one at a time, in a liquid flow stream;

laser for providing an incident beam of illumination directed at the cells in said flow stream;

a focusing lens positioned in the optical path of said light beam to focus said light beam on said cells flowing in the flow stream;

a light transmissive, substantially flat steering plate angularly positioned in the optical path between said lens and said flow stream for refracting the focused light beam to cause a displacement of the focal point of said light beam on said stream to thereby obtain an adjustment of said focused light beam;

means for detecting light associated with each moving cell as said cell passes through said adjusted, focused light beam; and

means for using said detected light to determine one or more characteristics of said cells.