An
eye tracking apparatus, an
eye tracking method and a head-mounted
display device. The
eye tracking apparatus comprises: a frame (100); an optical display module (200, 300), which is arranged on the frame (100); a
light source (500), which is arranged on the frame (100), wherein light of the
light source (500) can be reflected by eyeballs (400); a
reflective layer (600), which is arranged on the optical display module (200, 300) and is used for reflecting the light emitted by the
light source (500) and reflected by the eyeballs (400); a light sensor (700), which is arranged on the frame (100) and is used for receiving the light reflected by the
reflective layer (600) and / or the light of the light source (500) reflected by the eyeballs (400) so as to obtain
light sensing data, and transmitting the
light sensing data to a processor; and the processor, which is arranged on the frame (100), receives the
light sensing data from the light sensor (700), obtains
light intensity data on the basis of the light
sensing data, and determines the rotational angle of the eyeballs (400) on the basis of the
light intensity data and a preset mapping relationship. The eye tracking apparatus can overcome the problem of the
eye relief in an eye tracking apparatus being overly small, such that the position of the eyeballs (400) can be accurately tracked, and the
field of view (FOV) can be expanded.