Wearable near-to-eye (NTE) visualization systems are being developed by consumer electronics and social media companies to enable compelling experiences in augmented and virtual reality (AR/VR). VR immerses viewers mentally in a place other than the one in which they are physically present. Negative physiological side effects often limit VR usage to 10 min episodic sessions. AR involves symbology and/or imagery superimposed over the real world perceived in real time. AR NTE display system types include see-through (such as motorcycle visors, pilot helmets, or eyewear) and non-see-through with symbol overlays (for visualizing the world via passive or active electro-optic band cameras, imaging radar/lidar systems, or computer scene generators). VR systems are non-see-through only. Also, unlike VR, AR imagery is required to be conformal to the physical world surrounding the viewer. Accurate tracking of position, head, and eye are needed for some VR and all AR applications.

This special section of Optical Engineering comprises several papers addressing wearable vision systems (WVS) implemented as head- or helmet-mounted display systems. The paper by Schmerwitz et al. analyzes the human factors of conformal AR NTE displays for pilots in which 3-D symbology representing relevant real-world objects is presented on a see-through display such that it inherits the same optical flow as the physical environment in which the aircraft is operating. If successfully integrated with pilot workflow, such an AR system increases safety and expands flight operations (commercial, medical, civil, military) to include a variety of degraded visual environments. The paper by Peinecke et al. reviews conformal counterparts for several aircraft related instruments. The paper by Fischler et al. demonstrates the challenges of integrating an NTE system into a high-performance aircraft. The paper by Arthur et al. reviews NTE vision system research at NASA focused on advancing the state-of-the-art in displays, head-trackers, and flight data to guide regulatory guidance development for the NextGen commercial aviation industry. The paper by Harding and Rash identifies the luminance contrast requirements for full-color NTE see-through displays based on a perceptual study of the quality of white symbology against natural static backgrounds. The work in these five papers can provide important lessons learned to similar navigation and WVS challenges for ground vehicle operators and pedestrians.

The paper by Huang addresses a challenge for projection systems—compact optics—by developing an ultrashort throw design based on a telecentric lens and optimized Koehler illumination. All NTE systems are projectors (of small real images to virtual ones beyond the eye’s near point) and may benefit from future miniaturization of Huang’s approach.

The paper by Adil et al. addresses a fabrication efficiency challenge of NTE systems in which an image is projected to one eye via reflection off a coated portion inside one half of a spherical visor or lens. A Shack-Hartmann wavefront sensor is used to determine the aberrations in the visor parts, and a neural network framework is exploited to align the two halves.

The current period of significant commercial investment in WVS for personal communications and entertainment is driving rapid advances in miniature optoelectronics components and product design. Key challenges include achieving performance in a NTE visualization system sufficient to compel users to tolerate shortcomings including latency, acuity, field-of-view, fashion, and donning/doffing. We hope that this special section will help the community to leverage consumer-driven advancements in the design of specialty applications including automotive, industrial, and military vision systems.