摘要 |
A display device includes a display panel, an imaging unit, a contrast measuring unit, a detecting unit, a processing unit and an adjusting unit. The imaging unit includes a focus lens, an imaging sensor, and a stepper motor, the focus lens being driven by the stepper motor to a number of predetermined points, and capable of capturing an image at each predetermined point. The contrast measuring unit is for measuring contrast values of the captured images. The detecting unit is for comparing the measured contrast values, and detecting which one of the images has the highest contrast value. The processing unit is for calculating an object distance according to which predetermined point the focus lens was at when it captured the image with the highest contrast value, and generating a control signal. The adjusting unit is for adjusting the brightness of the display according to the control signal generated from the processing unit. |