DRIVER STATE ESTIMATION DEVICE AND DRIVER STATE ESTIMATION METHOD

A driver state estimation device which can estimate a distance to a head position of a driver without detecting a center position of a face area of the driver in an image, comprises a monocular camera 11 which can pick up an image of a driver sitting in a driver's seat, a storage section 15 and a CPU 12, the storage section 15 comprising an image storing part 15a for storing the image picked up by the monocular camera 11, and the CPU 12 comprising a head detecting section 23 for detecting a head of the driver in the image read from the image storing part 15a, a defocus amount detecting section 24 for detecting a defocus amount of the head of the driver in the image detected by the head detecting section 23 and a distance estimating section 25 for estimating a distance from the head of the driver sitting in the driver's seat to the monocular camera 11 with use of the defocus amount detected by the defocus amount detecting section 24.