Lenslet VR: Thin, Flat and Wide-FOV Virtual Reality Display Using Fresnel Lens and Lenslet Array

102˚ horizontal FOV mmFig. 1. (Left and right top) VR glasses prototype.(Right bottom) The monocular module of VR glasses prototype.The total thickness, including all optical components, required space, and the LCD is 8.8 mm.(Middle) Captured result of display experiment with the monocular benchtop prototype.The prototype covers a 102°x 102°FOV.The photo was taken with Samsung Galaxy S10 5G smartphone ultra-wide-angle camera ( f /2.2, 1.8 mm), which has a 104°x 88°FOV.The photo is a single frame in a video.Captured video result is provided in supplementary media.Video by HDVMaster on Motion Elements.Abstract-We propose a new thin and flat virtual reality (VR) display design using a Fresnel lenslet array, a Fresnel lens, and a polarization-based optical folding technique.The proposed optical system has a wide field of view (FOV) of 102˚×102˚, a wide eye-box of 8.8 mm, and an ergonomic eye-relief of 20 mm.Simultaneously, only 3.3 mm of physical distance is required between the display panel and the lens, so that the integrated VR display can have a compact form factor like sunglasses.Moreover, since all lenslet of the lenslet array is designed to operate under on-axis condition with low aberration, the discontinuous pupil swim distortion between the lenslets is hardly observed.In addition, all on-axis lenslets can be designed identically, reducing production cost, and even off-the-shelf Fresnel optics can be used.In this paper, we introduce how we design system parameters and analyze system performance.Finally, we demonstrate two prototypes and experimentally verify that the proposed VR display system has the expected performance while having a glasses-like form factor.