US 9,809,836 B2
Method of differentiating microbial colonies in an image
Phillip A. Bolea, Grant, MN (US)
Assigned to 3M Innovative Properties Company, St. Paul, MN (US)
Filed by 3M INNOVATIVE PROPERTIES COMPANY, Saint Paul, MN (US)
Filed on May 9, 2017, as Appl. No. 15/590,193.
Application 15/590,193 is a continuation of application No. 14/652,366, granted, now 9,677,108, previously published as PCT/US2013/074882, filed on Dec. 13, 2013.
Claims priority of provisional application 61/739,786, filed on Dec. 20, 2012.
Prior Publication US 2017/0240947 A1, Aug. 24, 2017
Int. Cl. G06K 9/00 (2006.01); C12Q 1/04 (2006.01); G01N 33/569 (2006.01)
CPC C12Q 1/04 (2013.01) [G01N 33/569 (2013.01); G06K 9/00134 (2013.01); G06K 9/00147 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A method, comprising:
using an imaging device to produce a first image of a thin film culture device, the culture device having a front side having a transparent film cover sheet and a back side having a translucent substrate;
wherein the first image is produced while providing illumination to the front side of the device;
wherein the culture device comprises first and second indicator compounds;
wherein the first indicator compound is converted by a microorganism to a first product having a first color;
wherein the second indicator compound is converted by a microorganism to a water-diffusible second product that forms a second color;
using the imaging device to produce a second image of the thin film culture device, wherein the second image is produced while providing illumination to the back side of the device;
analyzing the first and second images to identify microorganism colonies in each image;
analyzing the first image to calculate a first value of a size parameter for a colony at a particular location in the culture device;
analyzing the second image to calculate a second value of the size parameter at the particular location in the culture device; and
comparing the first value to the second value.