Method for determining slope of slide in slide scanning device, method for controlling slide scanning device and slide scanning device using the same

A method for determining a slope of a slide in a slide scanning device, the method comprising:

• obtaining, by a scanning control unit of a slide scanning device, z-stack images for at least a partial area of a sample disposed on a slide, the z-stack images including a plurality of slice images;
• extracting, by the scanning control unit, a z-axis location of each of the plurality of slice images in which a focus evaluation value along a plurality of lines is equal to or higher than a predetermined value within a predetermined ranking as a slope calculation z-axis location, the plurality of lines being a plurality of rows, respectively, or a plurality of columns, respectively;
• and
• calculating, by the scanning control unit, a first slope by using a distance according to a location of a horizontal plane of the plurality of lines and the slope calculation z-axis location, and estimating the first slope as a slope of the slide,
• wherein the extracting includes:
• calculating a mean focus evaluation value for each of the plurality of lines in each of the plurality of slice images;
• obtaining a maximum value among the mean focus evaluation values for respective lines of the plurality of slice images that are coincident along a z-axis;
• and
• normalizing the mean focus evaluation values for the respective lines that are coincident along the z-axis with the maximum value, and
• wherein the calculating of the first slope includes calculating the first slope by using the normalized mean focus evaluation values.