Observation device

An observation device that captures an image at a focal position inside a sample container that stores a sample liquid, comprising:

• a holding part that holds the sample container;
• an optical system that captures the image at the focal position;
• and
• a computation device that controls the optical system, wherein
• the optical system includes:
• an objective lens disposed below the sample container;
• an objective lens actuator that scans the objective lens in an optical axis direction;
• an irradiation unit that irradiates a bottom surface of the sample container with light;
• a detection unit that detects a reflected light intensity of reflected light of the light;
• a focus control unit that positions a focal point of the objective lens on a reflection surface imparting a peak in the reflected light intensity;
• and
• a reflected light intensity determination unit that determines, on the basis of intensity distribution of the reflected light, a position of the focal point,
• the computation device determines, on the basis of the position of the focal point of the objective lens determined by the reflected light intensity determination unit, a driving direction of the objective lens actuator,
• when the peak of the reflected light intensity is detected, the reflected light intensity determination unit determines whether or not the focal point is positioned at the focal position at the peak on the basis of the intensity distribution of the reflected light and the driving direction of the objective lens actuator when the peak is detected,
• the focus control unit drives the objective lens actuator to position the focal point at the focal position when the focal point is positioned at the focal position at the peak, and
• the computation device causes the optical system to capture an image if the focal point is positioned at the focal position and to drive the objective lens actuator when the focal point is not positioned at the focal position.

An observation device that captures an image at a focal position inside a sample container that stores a sample liquid, the observation device comprising:

• a holding part that holds the sample container;
• an optical system that captures the image at the focal position;
• and
• a computation device that controls the optical system, wherein
• the optical system includes:
• an objective lens disposed below the sample container;
• an objective lens actuator that scans the objective lens in an optical axis direction;
• an irradiation unit that irradiates a bottom surface of the sample container with light;
• a detection unit that detects a reflected light intensity of reflected light of the light;
• a focus control unit that positions a focal point of the objective lens on a reflection surface imparting a peak in the reflected light intensity;
• a camera that captures an image of a position of the focal point;
• and
• an imaging lens that forms the image of the position of the focal point on the camera,
• the computation device
• determines, from the image of the camera, whether the position of the focal point of the objective lens is in the sample liquid, in the bottom surface of the sample container, or in air, and determines, on the basis of the position of the focal point, a driving direction of the objective lens actuator, and
• when the peak of the reflected light intensity is detected, determines whether or not the focal point is positioned at the focal position at the peak on the basis of the image of the camera and the driving direction of the objective lens actuator when the peak is detected,
• the focus control unit drives the objective lens actuator to position the focal point at the focal position when the focal point is positioned at the focal position at the peak, and
• the computation device causes the optical system to capture an image if the focal point is positioned at the focal position and to drive the objective lens actuator when the focal point is not positioned at the focal position.