Specimen observation apparatus and specimen observation method

A specimen observation method for observing a specimen by using a specimen observation apparatus configured to observe the specimen contained in a specimen container, in which the specimen observation apparatus includes:

• an XY stage configured to move a specimen container holder supporting the specimen container in two directions along a horizontal direction,
• a light source configured to emit light in a direction perpendicular to the horizontal direction,
• an objective lens configured to collect the light transmitted through the specimen container,
• an imaging unit configured to capture an image of the specimen container by using the light collected by the objective lens, and
• an auto-focus mechanism configured to adjust a focal position of the objective lens, in which the specimen container has a shape in which a bottom surface of the specimen container and a side surface of the specimen container are connected by an inclined surface,
• the specimen observation method comprising:
• obtaining a luminance value for the image at a plurality of locations in the specimen container, prior to adjusting the focal position by the auto-focus mechanism;
• and
• identifying a central position of the specimen container in the horizontal direction,
• wherein identifying the central position includes:
• using a number of a high-luminance region, in which the luminance value for the image at a plurality of locations in the specimen container is equal to or higher than a threshold value, and a width of the high-luminance region in the horizontal direction, to identify the central position of the specimen container in the horizontal direction,
• or using a number of a low-luminance region, in which the luminance value for the image at a plurality of locations in the specimen container is less than the threshold value, and a width of the low-luminance region in the horizontal direction to identify a central position of the specimen container in the horizontal direction.