Spatial calibration of an optical see-through head-mounted display

Abstract

We present here a method for calibrating an optical see-through Head Mounted Display (HMD) using techniques usually applied to camera calibration (photogrammetry). Using a camera placed inside the HMD to take pictures simultaneously of a tracked object and features in the HMD display, we could exploit established camera calibration techniques to recover both the intrinsic and extrinsic properties of the HMD (width, height, focal length, optic centre and principal ray of the display). Our method gives low re-projection errors and, unlike existing methods, involves no time-consuming and error-prone human measurements, nor any prior estimates about the HMD geometry.

Optical see-through head mounted display direct linear transformation calibration robustness in the presence of user alignment noise

“…However, due to human fatigue it is reasonable to believe that there exists an optimal calibration quality as a function of the number of correspondence points versus deteriorating user alignment over the time it takes to construct the alignments. To reduce the effect of noise in "time-consuming and error-prone human measurements" Gilson et al (Gilson et al, 2008) replaces the user's eye with a camera during calibration to estimate the parameters of the OST HMD with techniques similar to that of VST calibration. The subsequent evaluation is however made with the same camera, and not with a human eye, and therefore does not illustrate the effects of mismatching camera and eye position.…”

Vision-based robust calibration for optical see-through head-mounted displays

“…Studies of OSTHMD calibration have been conducted with various types of tracking systems: magnetic-based systems [1,2], ultrasonic-based systems [3], infra-red based systems [4,5] and vision-based systems [6]. Among these, all except the vision-based systems generally provide high-accuracy tracking and high-speed processing.…”

A camera-based calibration for automotive augmented reality Head-Up-Displays

“…However, Optical SeeThrough Head-Mounted-Displays (OSTHMD) share many similarities with HUDs, as they also use a semi-transparent reflector as combiner to create a virtual image in front of the eye. There exist many approaches for the estimation of the projective properties [36,17,27,26,28,16,19]. Most of these methods rely on user interaction, where several virtual points on the display have to be aligned with real markers in the scene [36,17,27,26].…”

“…Most of these methods rely on user interaction, where several virtual points on the display have to be aligned with real markers in the scene [36,17,27,26]. Gao et al [16] and Gilson et al [19] create a setup which essentially replaces the human eye with a camera, so they obtain better means for the quantitative evaluation of the calibration accuracy. Common to all these approaches is that the projective characteristics of the display setup are represented by a single projection matrix (extrinsic and intrinsic parameters).…”