Image capturing apparatus, image forming apparatus, distance measuring method, and computer-readable recording medium

A distance measuring method to be performed by an image capturing apparatus including a casing having an opening, a light source arranged inside the casing, and a sensor arranged inside the casing and configured to capture, through the opening, an image of an object present outside the casing while the light source is on, the distance measuring method comprising:

• calculating a distance between the casing and the object, based on an image that has been captured by the sensor and contains, within an image region of the object defined by the opening, a high-luminance region and low-luminance regions located on outer sides of the high-luminance region.

A non-transitory computer-readable recording medium that contains a computer program for causing an image capturing apparatus to implement a function, the image capturing apparatus including a casing having an opening, a light source arranged inside the casing, and a sensor arranged inside the casing and configured to capture, through the opening, an image of an object present outside the casing while the light source is on, the function comprising:

• calculating a distance between the casing and the object, based on an image that has been captured by the sensor and contains, within an image region of the object defined by the opening, a high-luminance region and low-luminance regions located on outer sides of the high-luminance region.