Abstract: A wearable display system includes a light projection system having one or more emissive microdisplays, e.g., micro-LED displays. The light projection system projects time-multiplexed left-eye and right-eye images, which pass through an optical router having a polarizer and a switchable polarization rotator. The optical router is synchronized with the generation of images by the light projection system to impart a first polarization to left-eye images and a second different polarization to right-eye images. Light of the first polarization is incoupled into an eyepiece having one or more waveguides for outputting light to one of the left and right eyes, while light of the second polarization may be incoupled into another eyepiece having one or more waveguides for outputting light to the other of the left and right eyes. Each eyepiece may output incoupled light with variable amounts of wavefront divergence, to elicit different accommodation responses from the user's eyes.

Abstract: A fluid pressure operated braking system of the kind which includes an electrical system which is associated with wheels of the vehicle and arranged to regulate the braking force applied to the associated wheels, and which is operable automatically to effect release of a brake acting on the associated wheels when the deceleration thereof exceeds a predetermined amount and to re-apply the brake when the angular velocity of the respective wheels approaches that at which the periphery of the wheel rolls on the road surface without slipping. The system senses the time for which the brake is released and if the sensed time is greater than a predetermined time, the electrical system is rendered inoperative to permit re-application of the brake.