SIMPLE CODE READER

• US 20180053026A1
• Filed: 10/17/2017
• Published: 02/22/2018
• Est. Priority Date: 03/29/2016
• Status: Active Grant

• Current Assignee: Analog Devices, Inc.
• Original Assignee: Analog Devices, Inc.
• Inventors: DELIWALA, Shrenik, GUERY, Alain Valentin
• Granted Patent: US 10,007,823 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 2562/0295 Strip shaped analyte sensors for apparatus classified in A61B5/145 or A61B5/157 disposable multilayered or laminated electrodes G01N27/307; details of handling chemical test elements G01N33/4875
• CPC Class Codes: A61B 2562/08 Sensors provided with means for identification, e.g. barcodes or memory chips
• CPC Class Codes: A61B 5/00 Measuring for diagnostic purposes radiation diagnosis A61B6/00; diagnosis by ultrasonic, sonic or infrasonic waves A61B8/00; Identification of persons
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/15003 for venous or arterial blood
• CPC Class Codes: A61B 5/150358 Strips for collecting blood, e.g. absorbent optical reagent test strips G01N21/8483; chemical reagent test strips G01N33/4875, G01N33/52
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: G01N 33/66 involving blood sugars, e.g. galactose
• CPC Class Codes: G06K 19/06018 one-dimensional coding
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10732 Light sources
• CPC Class Codes: G06K 7/10821 further details of bar or optical code scanning devices
• CPC Class Codes: G06K 7/1404 Methods for optical code recognition

Abstract

Embodiments of the present disclosure provide code readers for reading codes provided as patterns imprinted on objects. Light interacts with a pattern by e.g. being reflected from or transmitted through the pattern, and at least some of the light that has interacted with the pattern is incident on photosensitive element(s) of one or more photodetectors of a code reader. The code reader employs centroid-measuring photodetector(s), i.e. photodetectors that detect light in such a manner that centroid of a pattern can be obtained directly from the photocurrents generated as a result of the photosensitive elements detecting light incident thereon. The code reader is then configured to process the detected light to determine a centroid of the pattern from the detected light and to decode data encoded in the pattern based on a position of the centroid. Such code readers are substantially less complex than camera-based devices and avoid mechanical scanning.

Claims

1. A code reading system comprising:

a first centroid-measuring photodetector configured to detect light that has interacted with a first pattern provided on an object, wherein the first pattern encode data and wherein the detected light is indicative of a centroid of the first pattern; and

a processing logic configured to;

determine the centroid of the first pattern from the detected light, and

determine the data encoded in the first pattern based on the determined centroids of the first pattern.

2. The code reading system according to claim 1, wherein the first centroid-measuring photodetector comprises a charge-generating region at least partially enclosed between at least a pair of charge-collecting electrodes, wherein:

the charge-generating region is configured to generate charge as a result of the light being incident on the region, and

amount of charge collected at each of the charge-collecting electrodes is indicative of the centroid of the first pattern.

3. The code reading system according to claim 2, further comprising a lens configured to image the first pattern onto the first centroid-measuring photodetector.

4. The code reading system according to claim 2, wherein the first centroid-measuring photodetector is in direct contact with the first pattern or are at a distance of less than 10 millimeters.

5. The code reading system according to claim 1, wherein the first centroid-measuring photodetector comprises:

a surface having an aperture; and

a pair of photodetectors electrically isolated from each other at a boundary between them, the boundary aligned with the aperture.

6. The code reading system according to claim 5, wherein:

each of the pair of photodetectors is configured to generate a respective photocurrent so that the pair of photodetectors is sufficient to detect the angle of incident light, the angle of incident light being detectable based on a ratio of the photocurrents generated respectively by the pair of photodetectors, and

the pair of photodetectors is aligned along an optical path without a lens, the optical path leading through the aperture and the photodetectors.

7. The code reading system according to claim 1, wherein the first centroid-measuring photodetector comprises a multi-pixel sensor configured to measure the centroid of the first pattern.

8. The code reading system according to claim 1, wherein:

the code reading system further comprises a second centroid-measuring photodetector provided at a predefined position with respect to the first centroid-measuring photodetector,

the object further has a second pattern provided thereon,

the second photodetector is configured to detect light that has interacted with the second pattern, wherein the light detected by the second photodetector is indicative of a centroid of the second pattern,

the processing logic is further configured to determine the centroid of the second pattern based on light detected by the second photodetector, and

decoding the data comprises decoding the data encoded in a combination of the first and second patterns based on a distance between the centroid of the first pattern and the centroid of the second pattern.

9. The code reading system according to claim 1, further comprising one or more light sources configured to generate light to interact with the first pattern provided on the object, where the one or more light sources are configured to illuminate the object with the generated light so that the light that has interacted with the first pattern comprises a portion of the generated light that is transmitted through or reflected from the first pattern.

10. The code reading system according to claim 9, wherein the one or more light sources are arranged so that the generated light is coupled into the object.

11. The code reading system according to claim 1, wherein the first pattern is a pattern of openings provided in the object.

12. The code reading system according to claim 1, wherein the first pattern is a unique coding pattern.

13. A method for reading a code provided as a pattern imprinted on a coded object, the method comprising:

receiving measurements from one or more centroid-measuring photodetectors of a code reader, the one or more centroid-measuring photodetectors configured to measure light that has interacted with the pattern when the coded object is affixed to, aligned with, or/and inserted into the code reader;

determining the centroid of the pattern based on the measurements; and

determining the code based on the determined centroid.

14. The method according to claim 13, wherein each of the one or more centroid-measuring photodetectors comprises:

a surface having an aperture; and

a pair of photodetectors electrically isolated from each other at a boundary between them, the boundary aligned with the aperture.

15. The method according to claim 13, wherein each of the one or more centroid-measuring photodetectors comprises a charge-generating region at least partially enclosed between at least a pair of charge-collecting electrodes, where the charge-generating region is configured to generate charge as a result of the light being incident on the region, and where an amount of charge collected at each of the charge-collecting electrodes is indicative of the centroid of the pattern.

16. The method according to claim 13, wherein each of the one or more centroid-measuring photodetectors comprises a multi-pixel sensor.

17. A code reading assembly comprising:

a code reader, and

a coded object having a code imprinted thereon as a pattern provided on the coded object, wherein the coded object is configured to be affixed to, aligned with, or/and inserted into the code reader for the code reader to read the code imprinted on the coded object,

wherein the code reader comprises;

one or more centroid-measuring photodetectors configured to detect light that has interacted with the pattern, wherein the detected light is indicative of a centroid of the pattern; and

a processing logic configured to;

determine the centroid of the pattern from the detected light, and

determine the code based on the determined centroid.

18. The code reading assembly according to claim 17, wherein:

the one or more centroid-measuring photodetectors comprise a first photodetector and a second photodetector provided at predefined positions with respect to one another,

said pattern is a first pattern,

the coded object further has a second pattern provided thereon,

the first photodetector is configured to detect light that has interacted with the first pattern, wherein the light detected by the first photodetector is indicative of the centroid of the first pattern,

the second photodetector is configured to detect light that has interacted with the second pattern, wherein the light detected by the second photodetector is indicative of a centroid of the second pattern,

the processing logic is configured to determine the centroid of the first pattern based on light detected by the first photodetector and to determine the centroid of the second pattern based on light detected by the second photodetector, where determining the code comprises determining the code encoded in the first and second patterns based on a distance between the centroid of the first pattern and the centroid of the second pattern.

19. The code reading assembly according to claim 17, wherein each of the one or more centroid-measuring photodetectors comprises:

a surface having an aperture; and

a pair of photodetectors electrically isolated from each other at a boundary between them, the boundary aligned with the aperture.

20. The code reading assembly according to claim 19, wherein:

each of the pair of photodetectors is configured to generate a respective photocurrent,

the pair of photodetectors is aligned along an optical path without a lens, the optical path leading through the aperture and the photodetectors, and

the processing logic is configured to determine the centroid of the pattern based on a ratio of the photocurrents generated by the pair of photodetectors.