Endoscope apparatus

An endoscope apparatus comprising:

• a light source configured to generate illumination light for illuminating a subject;
• a light source control unit configured to control turning on and off of the light source;
• an optical system configured to form an optical image of the subject illuminated with the illumination light;
• an imaging device including a plurality of pixels disposed in a matrix and configured to generate pixel signals of the pixels based on the optical image in each of a plurality of frames and generate an image of the subject using the pixel signals;
• an imaging device control unit configured to control the imaging device;
• a rolling distortion determination unit configured to determine a situation of occurrence of rolling distortion in the image;
• and
• a mode setting unit configured to perform switching between settings of a first mode and a second mode for the light source control unit and the imaging device control unit,
• wherein, when the first mode is set, the imaging device control unit causes the imaging device to perform a first scan for reading the pixel signals from the pixels in simultaneous exposure lines by consecutively scanning all the simultaneous exposure lines, the simultaneous exposure lines being some of a plurality of rows in an array of the plurality of pixels,
• when the first mode is set, the light source control unit causes the light source to be turned on during a first period and causes the light source to be turned off during a period including all of a second period,
• the first period is a period including all or a part of a period during which available storage periods of the pixels in all the simultaneous exposure lines overlap,
• the second period is a period during which a scan is performed for reading the pixel signals generated by the pixels in all the simultaneous exposure lines from the pixels during the first period,
• the imaging device generates a first image using the pixel signals generated by the pixels in all the simultaneous exposure lines during the period in which the available storage periods of the pixels in all the simultaneous exposure lines overlap,
• when the second mode is set, the imaging device control unit causes the imaging device to perform a second scan for reading the pixel signals from the pixels in the plurality of rows by consecutively scanning the plurality of rows,
• when the second mode is set, the light source control unit causes the light source to be turned on during a period including all of the available storage period of the pixels in each of the plurality of rows before the second scan is performed,
• the imaging device generates a second image using the pixel signals read by the second scan, and
• the rolling distortion determination unit determines the situation of the occurrence of the rolling distortion using the first image and the second image.