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

Patent metadata

Field	Value
Publication number	US-12591123-B2
Application number	US-202418947670-A
Country	US
Kind code	B2
Filing date	Nov 14, 2024
Priority date	Nov 20, 2023
Publication date	Mar 31, 2026
Grant date	Mar 31, 2026

Abstract

An embodiment relates to a method for determining a slope of a slide in a slide scanning device, which includes: (a) obtaining, by a scanning control unit of a slide scanning device, z-stack images for at least a partial area of a sample of a slide; (b) extracting, by the scanning control unit, a z-axis location of a slice image in which a focus evaluation value has a top value of a predetermined ranking along a plurality of lines of any one of a plurality of rows or a plurality of columns of the z-stack images as a slope calculation z-axis location; and (c) calculating, by the scanning control unit, a 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 calculated slope as the slope of the slide.

First claim

What is claimed is:

1 . 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.

2 . The method of claim 1 , wherein in the extracting,
the plurality of lines include a first line to an m-th line (m is a natural number of 2 or more), the plurality of slice images include a first slice image to a k-th slice image in a z-axis direction, the scanning control unit calculates focus evaluation values of the first line to the m-th line of each of the first slice image to the k-th slice image, and the scanning control unit extracts, as the slope calculation z-axis location, the z-axis location of each of the plurality of slice images in which the focus evaluation value is equal to or higher than the predetermined value within the predetermined ranking with respect to each of the first line to the m-th line.

3 . The method of claim 2 ,
wherein each of the focus evaluation values of the first line to the m-th line is a mean of focus evaluation values acquired by averaging focus evaluation values of pixels included in a corresponding line with respect to each of the first line to the m-th line of each of the first slice image to the k-th slice image.

4 . The method of claim 3 ,
wherein the mean of the focus evaluation values is normalized with a maximum value among the means of the focus evaluation values included in the corresponding line with respect to each of the first line to the m-th line.

5 . The method of claim 4 ,
wherein the slope is calculated by applying a linear regression by using the normalized focus evaluation values.

6 . The method of claim 3 ,
wherein the focus evaluation value of each of the pixels is calculated by using any one of a Tenengrad function, a Squared Gradient function, a Brenner function, a Variance function, or a Laplacian function.

7 . The method of claim 1 ,
wherein the estimated slope is a slope at which the slide forms with respect to a plane perpendicular to an optical axis of an image photographing unit.

8 . The method of claim 1 ,
wherein the plurality of lines are the plurality of columns of the z-stack images, and the estimated slope is a slope of the slide in a first direction.

9 . The method of claim 1 ,
wherein the plurality of lines are the plurality of rows of the z-stack images, and the estimated slope is a slope of the slide in a second direction.

10 . A slide scanning device, comprising:
a stage having a slide mounted thereon; an image photographing unit configured to acquire an image of a sample of the slide; and a scanning control unit configured to control the image photographing unit or the stage to scan the image of the sample, wherein the scanning control unit includes a slope calculation unit configured to perform the method for determining the slope of the slide of claim 1 .

11 . The slide scanning device of claim 10 ,
wherein the scanning control unit further includes a focus map generation unit configured to search focal locations in a focus map generation FOV in z-stack images obtained in focus map generation FOVs at a plurality of locations of the sample, and generating a focus map for the sample.

12 . The slide scanning device of claim 11 ,
wherein the scanning control unit is configured to set a focal location of the image photographing unit in a specific FOV according to the focus map, and adjust the focal location of the image photographing unit in an FOV subsequent to the specific FOV according to the slope of the slide estimated by the slope calculation unit.

13 . The slide scanning device of claim 11 ,
wherein the focus map generation unit is configured to the focus map according to the slope of the slide estimated by the slope calculation unit.

14 . The slide scanning device of claim 11 ,
wherein the slope calculation unit is configured to estimate the slope of the slide by using the z-stack images acquired in at least one of the focus map generation FOVs.

15 . A method for controlling a slide scanning device including a stage on which a slide is mounted, an image photographing unit acquiring an image of a sample of the slide, and a scanning control unit controlling the image photographing unit or the stage so as to scan the image of the sample, the method comprising:
a focus map generation step of searching, by the scanning control unit, a focal location in a plurality of focus map generation FOVs with respect to the sample, and generating a focus map; a slide slope determining step of determining, by the scanning control unit, the slope of the slide of claim 1 ; an image acquisition step of driving, by the scanning control unit, the image photographing unit and the stage to acquire a plurality of tile images for the sample by the image photographing unit; and an image generation step of stitching the plurality of tile images and generating a slide image for the sample.

16 . The method of claim 15 ,
wherein in the image acquisition step, the scanning control unit sets a focal location of the image photographing unit in a specific FOV according to the focus map, and adjusts the focal location of the image photographing unit in an FOV subsequent to the specific FOV according to the slope of the slide determined in the slide slope determining step.

17 . The method of claim 15 , further comprising:
a focus map correcting step of correcting the focus map according to the slope of the slide estimated by a slope calculation unit.

Assignees

• Vieworks Co Ltd

Inventors

• Kim Byeongyeon
• Park Yeonhee

Classifications

• H04N23/675

  comprising setting of focusing regions · CPC title

• G01N2021/177

  Detector of the video camera type · CPC title

• G02B21/365

  Control or image processing arrangements for digital or video microscopes (G02B21/361, G02B21/362 take precedence) · CPC title

• G02B21/008 Primary

  Details of detection or image processing, including general computer control · CPC title

• G02B21/26

  Stages; Adjusting means therefor · CPC title