Abstract: A microbiological testing method or assay for identifying an organism grown on one chromagenic semisolid nutrient media such as agar, where the organism exhibits at least one color or chromatic aspect. A digitized electrical signal is generated encoding an image of the organism on the nutrient media. The encoded image is stored and digitally processed to detect the color of the organism on the nutrient media. Chromatic characteristics of a multiplicity of known organisms are stored in an electronic library. A computer is operated to compare the detected color of the organism with chromatic characteristics stored in the library.

Abstract: An apparatus for use in carrying out a microbiological assay on samples in a petri plate has a support for holding the petri plate, a camera, and a plurality of diffuse-white-light emitting diodes. The camera optically detects microbe-growth inhibition zones arising about the diffusion disks and is disposed above the support. The diodes are disposed in a circular array above the support and below the camera for illuminating the nutrient medium and the drug diffusion disks. An electrical power and control circuit energizes the diodes with power from the computer upon an activation of the camera.

Abstract: A method and associated apparatus for use in a microbiological assay procedure wherein a plurality of diffusion disks are placed on a nutrient medium on a plate, each of the disks carrying a respective antibiotic agent and each having an identification code identifying the respective antibiotic agent, the disks being positioned on the plate in a preselected relative arrangement. The method comprises optically scanning the disks on the plate, consequently generating a digitally encoded image including digitized representations of the identification codes, and electronically processing the digitally encoded image to determine an angle of rotation of the plate relative to a pre-established reference frame or coordinate system, wherein the electronic processing of the digitally encoded image includes detecting a region of the plate occupied by a unique subset of the disks.

Abstract: A microbiological assay investigatory apparatus has a source of electromagnetic waveform energy, a support and a linear color sensor. The support serves to hold a microbiological assay tray in a predetermined location relative to the source and to the sensor. The assay tray has different reaction chemicals and microorganisms of the same type in respective wells or chambers. The linear color sensor is disposed in a predetermined position relative to the support and concomitantly the assay tray for receiving electromagnetic waveform radiation emanating from a linear array of the wells in response to waveform energy from the source. The linear color sensor generates a signal encoding colorimetric data pertaining to a series of samples lying along a line intersecting the linear array of the wells.