Absolute radiometric and photometric measurements of near‐eye displays

The arrival of near‐eye displays has challenged the traditional methods that have been used to measure the optical properties of displays. Near‐eye displays typically create virtual images and are designed for the relatively small entrance pupil of the human eye. These two attributes result in optical measurement requirements that are substantially different from traditional flat panel displays. This paper discusses the optical system requirements needed to make absolute radiometric and photometric measurements of near‐eye displays. These guidelines are contrasted with the performance of current optical measurement instruments. An initial study was conducted using traditional and modified instruments and exhibited a significant variance in the results with different near‐eye display designs. The study demonstrated that some traditional optical instruments can yield erroneous results when used to measure near‐eye displays. Generic optical system design concepts were used to interpret the experimental results and helped to identify how current commercial designs could be modified to properly measure near‐eye displays.     

A multi‐plane optical see‐through head mounted display design for augmented reality applications

Augmented reality (AR) display technology greatly enhances users' perception of and interaction with the real world by superimposing a computer‐generated virtual scene on the real physical world. The main problem of the state‐of‐the‐art 3D AR head‐mounted displays (HMDs) is the accommodation‐vergence conflict because the 2D images displayed by flat panel devices are at a fixed distance from the eyes. In this paper, we present a design for an optical see‐through HMD utilizing multi‐plane display technology for AR applications. This approach manages to provide correct depth information and solves the accommodation‐vergence conflict problem. In our system, a projector projects slices of a 3D scene onto a stack of polymer‐stabilized liquid crystal scattering shutters in time sequence to reconstruct the 3D scene. The polymer‐stabilized liquid crystal shutters have sub‐millisecond switching time that enables sufficient number of shutters to achieve high depth resolution. A proof‐of‐concept two‐plane optical see‐through HMD prototype is demonstrated. Our design can be made lightweight, compact, with high resolution, and large depth range from near the eye to infinity and thus holds great potential for fatigue‐free AR HMDs.     

An 18 megapixel 4.3″ 1443 ppi 120 Hz OLED display for wide field of view high acuity head mounted displays

We developed and fabricated the world's highest resolution (18 megapixel, 1443 ppi) OLED on glass display panel. The design uses a white OLED with color filter structure for high density pixelization and an n‐type LTPS backplane for faster response time than mobile phone displays. A custom high bandwidth driver IC was fabricated. We developed a foveated pixel pipeline appropriate for virtual reality and augmented reality applications, especially mobile systems.