Line-of-sight detection device and method for detecting line of sight

A line-of-sight detection device, comprising:

• an image data acquisition unit configured to acquire image data of a face of a subject irradiated with detection light emitted from at least one light source;
• a line-of-sight detection unit configured to detect a line of sight of the subject based on the image data;
• an image processing unit configured to perform image processing on the image data to separately generate a feature image of the face and an eyeglasses reflection image indicating a reflection image of the at least one light source on eyeglasses worn on the face;
• and
• a display controller configured to cause a display device to display the feature image and the eyeglasses reflection image in a different display form in a composite image in which the feature image and the eyeglasses reflection image are combined, wherein
• the image processing unit is further configured to generate the feature image and the eyeglasses reflection image based on the image data obtained at a time when the detection light of a first amount of light is emitted from the at least one light source and the image data obtained at a time when the detection light of a second amount of light larger than the first amount of light is emitted from the at least one light source,
• the at least one light source includes a first light source and a second light source disposed at a different position,
• the detection light of the first amount of light is emitted from the first light source, and the detection light of the second amount of light is emitted from the second light source, and
• the first light source and the second light source alternately emit the detection light.