An image inspection apparatus comprising an image capturing unit for capturing images of an object; a transparent illumination unit (20, 120, 220, 320) which is disposed between the object and the image capturing unit, has a light-emitting surface for radiating light to the object and is configured to be able to select a light-emitting position on the light-emitting surface and control a radiation direction of the light; and a control unit for controlling the image capturing unit and the illumination unit (20, 120, 220, 320), wherein the control unit is configured to cause the illumination unit (20, 120, 220, 320) to radiate light to the object in a first direction and cause the light directed in the first direction to scan by changing the light-emitting position on the light-emitting surface in a first scanning of the illumination unit (20, 120, 220, 320), and cause the image capturing unit to capture images of the object during the first scanning, and wherein the control unit is configured to cause the illumination unit (20, 120, 220, 320) to radiate light to the object in a second direction different from the first direction, and cause the light directed in the second direction to scan by changing the light-emitting position on the light-emitting surface in a second scanning of the illumination unit (20, 120, 220, 320), and cause the image capturing unit to capture images of the object during the second scanning, and wherein the control unit is configured to identify the respective light-emitting position of the illumination unit (20, 120, 220, 320) when a measurement point of the surface of the object is illuminated from images of the object captured during the first scanning and the second scanning, and calculate a distance from the light-emitting surface to the measurement point on the basis of the identified light-emitting positions, the first direction and the second direction. an image capturing unit for capturing images of an object; a transparent illumination unit (20, 120, 220, 320) which is disposed between the object and the image capturing unit, has a light-emitting surface for radiating light to the object and is configured to be able to select a light-emitting position on the light-emitting surface and control a radiation direction of the light; and a control unit for controlling the image capturing unit and the illumination unit (20, 120, 220, 320), wherein the control unit is configured to cause the illumination unit (20, 120, 220, 320) to radiate light to the object in a first direction and cause the light directed in the first direction to scan by changing the light-emitting position on the light-emitting surface in a first scanning of the illumination unit (20, 120, 220, 320), and cause the image capturing unit to capture images of the object during the first scanning, and wherein the control unit is configured to cause the illumination unit (20, 120, 220, 320) to radiate light to the object in a second direction different from the first direction, and cause the light directed in the second direction to scan by changing the light-emitting position on the light-emitting surface in a second scanning of the illumination unit (20, 120, 220, 320), and cause the image capturing unit to capture images of the object during the second scanning, and wherein the control unit is configured to identify the respective light-emitting position of the illumination unit (20, 120, 220, 320) when a measurement point of the surface of the object is illuminated from images of the object captured during the first scanning and the second scanning, and calculate a distance from the light-emitting surface to the measurement point on the basis of the identified light-emitting positions, the first direction and the second direction.