Optical reader for diffraction grating-based encoded optical identification elements

• US 20060071075A1
• Filed: 10/01/2004
• Published: 04/06/2006
• Est. Priority Date: 08/20/2002
• Status: Active Grant

• Current Assignee: Illumina Incorporated
• Original Assignee: Illumina Incorporated
• Inventors: Fournier, David R., Kersey, Alan D., Li, Tuo, Putnam, Martin A., Moon, John A.
• Granted Patent: US 7,441,703 B2
• Time in Patent Office: Days
• US Class Current: 235/454
• CPC Class Codes: B01J 2219/005 Beads
• CPC Class Codes: B01J 2219/0056 Raised or sunken areas
• CPC Class Codes: G06K 19/06009 with optically detectable marking G06K19/063, G06K19/08 take precedence
• CPC Class Codes: G06K 2019/06225 using wavelength selection, e.g. colour code
• CPC Class Codes: G06K 2019/06234 miniature-code
• CPC Class Codes: G06K 2019/0629 Holographic, diffractive or retroreflective recording
• CPC Class Codes: G06K 7/1094 the record carrier being at least partially of the hologram type
• CPC Class Codes: G06K 7/12 using a selected wavelength, e.g. to sense red marks and ignore blue marks
• CPC Class Codes: G07D 7/0032 using holograms
• CPC Class Codes: G07D 7/004 using digital security elements, e.g. information coded on a magnetic thread or strip

Abstract

An optical reader system 7 for diffraction grating-based encoded microbeads (or bead reader system), comprises a reader box 100, which accepts a bead cell (or cuvette) 102 that holds the microbeads 8, having an embedded code therein. The reader box 100 interfaces along lines 103 with a known computer system 104. The reader box 100 interfaces with a stage position controller 112 and the controller 112 interfaces along a line 115 with the computer system 104 and a manual control device (or joy stick) 116 along a line 117. The reader interrogates the microbeads to determine the embedded code and/or the fluorescence level on the beads. The reader provides information similar to a bead flow cytometer but in a planar format, i.e., a virtual cytometer.

Claims

1. An optical reader for reading microbeads, comprising:

said reader capable of receiving at least one a substrate having at least one diffraction grating disposed therein, said grating having a resultant refractive variation at a grating location;

said grating providing an output optical signal indicative of a code when illuminated by an incident light signal propagating in free space;

a source light providing said input light signal incident at a location where said microbeads are located when loaded; and

a reader which reads said output optical signal and provides a code signal indicative of said code.

2. The apparatus of claim 1 wherein said source light comprises an optical code signal and an optical fluorescence excitation signal.

3. The apparatus of claim 2 wherein said output signal comprises a fluorescent optical signal from said substrate and said reader reads said output optical signal and provides a signal indicative of said fluorescent optical signal.

4. The apparatus of claim 2 wherein said optical fluorescence excitation signal comprises light at about 633 nm.

5. The apparatus of claim 2 wherein said optical fluorescence excitation signal comprises light at about 532 nm.

6. The apparatus of claim 1 wherein said microbead is made of a glass material.

7. The apparatus of claim 1 wherein said code comprises a plurality of bits.

8. The apparatus of claim 1 wherein the number of pitches is indicative of the number of said bits in said code.

9. The apparatus of claim 1 wherein said substrate has a length that is less than about 500 microns.

10. The apparatus of claim 1 wherein said substrate has a cylindrical shape.

11. The apparatus of claim 1 wherein said code comprises at least a predetermined number of bits, said number being:

3, 5, 7, 9, 10, 12, 14, 16, 18, 20, 24, 28, 30, 40, 50, or 100.

12. The apparatus of claim 1 wherein said substrate is a particle or bead.

13. A method of reading a code in an encoded substrate, comprising:

obtaining a substrate at least a portion of which having at least one diffraction grating disposed therein, said grating having a resultant refractive variation at a grating location;

said grating providing an output optical signal indicative of a code when illuminated by an incident light signal propagating in free space;

illuminating said substrate with said incident light, said substrate providing an output light signal; and

reading said output light signal and detecting a code and fluorescence therefrom.

14. The method of claim 13 wherein said substrate is a particle or bead.