Stereo parallax and disparity in single-lens stereoscopy

Single-lens stereoscopy (SLS) is the method where a stereo pair is derived by sampling light from two sides of an aperture within a single optical path. I first review the formation of the two images and the characteristics of these images. Of special interest are the differences between single-lens stereoscopy and dual-lens stereoscopy (DLS). Then I consider various practical considerations of using this method to make real-world products. Some of the questions to be addressed are: How do we form left and right images in a single-lens system? What causes the disparity between the two images? Just where is that aperture in a real optical device, anyway? What is the stereo parallax for an SLS system? How is disparity related to object depth (and is it different for DLS systems)? Can we measure a stereoscopic "sense of depth" or "depth effect"? How can we produce a strong depth effect in a SLS camera? How much depth effect is produced by the camera and how much by the display? What is the overall transformation from "Object Space" (the real world) to "Virtual Space'" (what we see)? How do we measure the sense of depth produced by the overall system?.