With the first commercial version of the Oculus Rift (Rift CV1) now trickling out of warehouses, and Rift DK2, HTC Vive DK1, and Vive Pre already being in developers’ hands, it’s time for a more detailed comparison between these head-mounted displays (HMDs). In this article, I will look at these HMDs’ lenses and optics in the most objective way I can, using a calibrated fish-eye camera (see Figures 1, 2, and 3).
Figure 1: Picture from a fisheye camera, showing a checkerboard calibration target displayed on a 30″ LCD monitor.
Figure 2: Same picture as Figure 1, after rectification. The purple lines were drawn into the picture by hand to show the picture’s linearity after rectification.
Figure 3: Rectified picture from Figure 2, re-projected into stereographic projection to simplify measuring angles. Concentric purple circles indicate 5-degree increments away from the projection center point.
“Can I make a full-field-of-view AR or VR display by directly shining lasers into my eyes?”
Well, technically, you can, but not in the way you probably imagine if you asked that question. What you can’t do is mount some tiny laser emitter somewhere out of view, have it shine a laser directly into your pupil, and expect to get a virtual image covering your entire field of view (see Figure 1). Light, and your eyes, don’t work that way.
Figure 1: A magical retinal display using a tiny laser emitter somewhere off to the side of each eye. This doesn’t work in reality. If a single beam of light entering the eye could be split up to illuminate large parts of the retina, real-world vision would not work.