Patent ID: 7391515
Filing Date: 2008-06-24
Classification: G01N

Abstract:
1. A method and apparatus for increased sensitivity of one or more image sensors which permits the detection and measurement of changes in the solution opacity and/or particle size distribution over a period of time, within a predetermined size range, contained in an injectable solution, with a density greater than or less than the solution, in a transparent container therefore, said method comprising the steps of: a) Pre-storing the container at an angle to the vertical for a sufficient time to permit the movement of all particles to reach their stable positions in either the heel of the container or the high point of the meniscus; b) marking the container with a human readable or 2-D matrix code which uniquely identifies individual containers without reducing visibility of the surface or the contents of the container; c) the code is applied using laser marker, ink-jet printer, or indelible print on an adhesive label applied to the surface of the container; d) each container is identified using an optical reading device such as machine vision system or bar code scanning device prior to placement in the inspection station; e) movement of particles in the container whereby rotation of the container using a predefined velocity motion profile causes substantially all of the particles in the solution in the container to experience a change in position with a corresponding change in time; f) an image processing computer for image acquisition, image storage and image processing capability; g) the image processing computer comprising memory for storing the images formed by the sensor; h) the image processing computer also comprising digital parallel input/output digital serial, and Ethernet communication capabilities for providing messages to external devices to report one or more measurements or characteristics of the particles or area of different matter opacity; i) the image processing computer executing control software stored in a computer-readable medium, which allows request and response signals from external devices indicating a specific size container to be inspected, which causes the image processing computer to perform image alignment and analysis for extraction of key characteristics in defined inspection zones in the container, as well as causing the image processing computer to store a reference images of an acceptable quality container in a memory location referenced by a specific identification code that is unique to a specific product or type, as well as causing a determination of the exact position of the container by extracting one or more edges of the reference container; j) the image processing computer comprising memory for storing (recording) the properties of particles isolated in each defined inspection volume by each of the sensors; k) recording the percentage of material with an opacity greater than a specified level isolated in each defined inspection volume by each of the sensors; l) determine the mean of the particle properties in each defined inspection volume over “n” images, primary properties included the geometric shape and integration of grayscale values over the geometric shape using each of the sensors; m) evaluate the particle only if its properties lie within a specific range of the mean of “x” samples and establish a mean equivalent pixel width in each corresponding inspection volume using each of the sensors; n) creating a calibration curve by evaluating NIST traceable dimensional standards in a typical final container with a fill volume of WFI (water for injection) equivalent to that used for the product to the equivalent pixel width of the particle in each corresponding inspection volume for each of the sensors implementing in the system; o) using one or more numerical calculations are performed to correlate particle size in pixels to equivalent physical dimension in micrometers using calibration curve established by measuring NIST traceable single seeded particle standards in each of the defined inspection volumes for each of the sensors implemented in the system; p) characterized in that the one or more photo detector(s) are positioned relative to the container, whereby a focal point of detection coincides with the center of the cross sectional diameter, whereby the center of at least on of the detectors is positioned above the bottom of the container so to view substantially all of the container bottom, whereby the detected particles in solution move in the corresponding inspection volumes of the container; wherein said lighting means provides a contrasting geometric or grayscale size and shape of said particles as well as very sufficient grayscale sensitivity to detect solution opacity changes at least an order of magnitude better than human inspection techniques; q) creating and storing a unique record for all of the inspection parameters, time of an inspection, date of an inspection, compiled and individual sensor inspection results, including but not limited to the number of particles present, the size of particles in measurement volumes, the fluid opacity and any changes as compared to the last inspection record.