An imaging apparatus, comprising: a light source unit configured to emit first illumination light and second illumination light that have illumination intensities different from each other as illumination light that illuminates a subject; a sensor unit having a plurality of pixels on a plurality of one-dimensional lines, each of the plurality of pixels generating an electric signal by performing light exposure and photoelectric conversion, the plurality of one-dimensional lines being arranged parallel to one another on a two-dimensional surface and including first and last lines, the sensor unit being configured to read pixel information by a focal-plane method from the plurality of pixels so as to read from the first line to the last line in a one-frame period (Tf); a light source controller configured to cause the light source unit to emit the first illumination light in a first illumination period that is a period between an emission start time of the first illumination light and an emission end time of the first illumination light, and to emit the second illumination light in a second illumination period that is a period between an emission start time of the second illumination light and an emission end time of the second illumination light in such a way that the first illumination period and the second illumination period switch alternately and continuously, the one-frame period (Tf) being set in the first illumination period and the second illumination period; and an imaging controller configured to cause the sensor unit to perform light exposure in a period striding over the first illumination period and the second illumination period, and to selectively acquire one of a first image signal based on the pixel information read by the sensor unit in the first illumination period, and a second image signal based on the pixel information read by the sensor unit in the second illumination period, as different areas in one frame. a light source unit configured to emit first illumination light and second illumination light that have illumination intensities different from each other as illumination light that illuminates a subject; a sensor unit having a plurality of pixels on a plurality of one-dimensional lines, each of the plurality of pixels generating an electric signal by performing light exposure and photoelectric conversion, the plurality of one-dimensional lines being arranged parallel to one another on a two-dimensional surface and including first and last lines, the sensor unit being configured to read pixel information by a focal-plane method from the plurality of pixels so as to read from the first line to the last line in a one-frame period (Tf); a light source controller configured to cause the light source unit to emit the first illumination light in a first illumination period that is a period between an emission start time of the first illumination light and an emission end time of the first illumination light, and to emit the second illumination light in a second illumination period that is a period between an emission start time of the second illumination light and an emission end time of the second illumination light in such a way that the first illumination period and the second illumination period switch alternately and continuously, the one-frame period (Tf) being set in the first illumination period and the second illumination period; and an imaging controller configured to cause the sensor unit to perform light exposure in a period striding over the first illumination period and the second illumination period, and to selectively acquire one of a first image signal based on the pixel information read by the sensor unit in the first illumination period, and a second image signal based on the pixel information read by the sensor unit in the second illumination period, as different areas in one frame.