Using texture maps to correct for optical distortion in head-mounted displays

This paper describes a fast method of correcting for optical distortion in head-mounted displays (HMDs). Since the distorted display surface in an HMD is not rectilinear, the shape and location of the graphics window used with the display must be chosen carefully, and some corrections made to the predistortion model. A distortion correction might be performed with optics that reverse the distortion caused by HMD lenses, but such optics can be expensive and offer a correction for only one specific HMD. Integer incremental methods or a lookup table might be used to calculate the correction, but an I/O bottleneck makes this impractical in software. Instead, a texture map may be defined that approximates the required optical correction. Recent equipment advances allow undistorted images to be input into texture mapping hardware at interactive rates. Built in filtering handles predistortion aliasing artifacts.