Calibration of imaging device for biological/chemical samples

A method for calibrating an imaging system for imaging biological or chemical samples, the method comprising:

• for each of a plurality of initial effective distances from an optical component of the imaging system to a calibration target at a sample location, identifying an initial optimal focus setting of the optical component, wherein different initial effective distances correspond to different initial optimal focus settings of the optical component;
• and
• storing data for the imaging system to determine a first functional approximation that is derived from the initial optimal focus settings of the optical component for the initial effective distances, the data being stored in at least one non-transitory computer readable medium that is adapted to be communicably coupled with the imaging system,
• wherein the first functional approximation is operable for calculating a new optimal focus setting of the optical component for a new effective distance having a different numerical value that is not a numerical value of one of the initial effective distances, the new effective distance being from a biological or chemical sample to the optical component, the biological or chemical sample not being the calibration target, and
• wherein the calibration target has a higher contrast than the biological or chemical samples, and wherein the calibration target includes at least one object of known size;
• for each of a plurality of images acquired at the initial effective distances:
• using the identified initial optimal focus setting of the optical component to determine a correlation of the known size to a number of pixels;
• and
• based on the correlation of the known size to a number of pixels, determining a size of the image;
• and
• storing data for the imaging system to determine a second functional approximation that is derived from the sizes at the initial effective distances, the data being stored in the at least one non-transitory computer readable medium that is adapted to be communicably coupled with the imaging system, wherein the second functional approximation is operable for calculating a new effective distance that is not one of the initial effective distances from a size.

An imaging system for imaging biological or chemical samples, the imaging system comprising:

• an optical component having a plurality of focus settings;
• a zoom lens for changing a value of a new effective distance from the optical component to a biological or chemical sample;
• at least one non-transitory computer readable medium that stores:
• first data for the imaging system to determine a first functional approximation that is derived from initial optimal focus settings of the optical component for a plurality of initial effective distances from the optical component of the imaging system to a calibration target at a sample location, and
• second data for the imaging system to determine a second functional approximation that is derived from flat-field corrections at the initial effective distances, wherein the second functional approximation is operable for calculating a flat-field correction for a new effective distance that is not one of the initial effective distances;
• one or more processors configured to map any value of effective distance to an optimal focus setting by:
• determining the first functional approximation from the first data stored in the at least one non-transitory computer readable medium, and
• inputting a selected effective distance into the first functional approximation to obtain the optimal focus setting, wherein the effective distance is a zoom setting, wherein the selected effective distance is not one of a plurality of initial effective distances;
• and
• a controller configured to set the optical component to have the optimal focus setting that maps to the selected effective distance,
• wherein the one or more processors are further configured to:
• determine the second functional approximation from the second data stored in the at least one non-transitory computer readable medium;
• and
• inputting the selected effective distance into the second functional approximation to calculate the flat-field correction;
• and
• using the flat-field correction to create a corrected image of the sample.