Thursday, October 6, 2016

Progress in wearable displays

Yesterday afternoon, Bernard Kress, Partner Optical Architect at Microsoft Corp, in the HoloLens project, gave a talk at the Stanford Center for Image Systems Engineering (SCIEN) with the title "Human-centric optical design: a key for next generation AR and VR optics." Here is the abstract:

The ultimate wearable display is an information device that people can use all day. It should be as forgettable as a pair of glasses or a watch, but more useful than a smartphone. It should be small, light, low-power, high-resolution and have a large field of view (FOV). Oh, and one more thing, it should be able to switch from VR to AR.

These requirements pose challenges for hardware and, most importantly, optical design. In this talk, I will review existing AR and VR optical architectures and explain why it is difficult to create a small, light and high-resolution display that has a wide FOV. Because comfort is king, new optical designs for the next-generation AR and VR system should be guided by an understanding of the capabilities and limitations of the human visual system.

There are three kinds of wearable displays:

  • Smart eyewear: extension of eyewear. Example: Google Glass
  • Augmented reality (AR) and mixed reality (MR): extension of the computer. An MR display has a built-in 3d scanner to create a 3d model of the world
  • Virtual reality (VR): extension of the gaming console

Bernard surveyed all avenues in wearable displays from their inception to the projections in the future. The speed of the presentation and the amount of material made it impossible to follow the talk unless you are an expert in the field. After the presentation, Bernard told me the size of his PowerPoint file is about 250 MB!

My takeaway was that the biggest issue in wearable displays is cost. So far, the optics engineers designed with cameras in mind and over-designed. The current breakthrough is that now the optics engineers start understanding the HVS, so they can design systems that are just as good as our MTF. Bernard claims that so far the industry has been mostly about hype but in 2017, products will take off and the new challenge is "show me the money."

By Microsoft Sweden [CC BY 2.0 (], via Wikimedia Commons