Automatic Parallax Measurement Method for Head-Up Display System

Parallax is a key factor to measure or collimate in head-up display (HUD) or other optical telescope systems. An automatic parallax measurement method is proposed and applied in HUD. The method uses lens zooming to change imaging quality, evaluates optimum imaging condition according to image property of gradient of intensity or saturation of color. Based on imaging quality evaluated, CCD imaging system, computer, precision mechanical movement system (MMS) and zooming lens build up a close loop control circuit to perform auto-focusing function. The defocusing amount and parallax are calculated according to the recorded position of zooming lens in the auto-focusing process. Furthermore, a novel algorithm of colored object auto-focusing evaluation is introduced. The result show the method is feasible and can measure parallax of HUD automatically and quantitatively.