Effects of HMD Backlight Bleed-Through in Low-Light Augmented Reality Applications
Abstract
Many liquid crystal displays (LCDs) operate by acting as a light valve to selectively block or transmit light emitted from a backlight. Due to the imperfect nature of the LCD light valve, when the LCD pixel is in the off state, it is not perfectly opaque, and some small portion of the backlight bleeds through. This imperfect dark state, or black level, is a well-known drawback of LCD displays. In low-light augmented reality helmet mounted display (HMD) applications, this bleed-through can significantly obscure real-world objects viewed through the display. In this work, we investigate the performance impact of a non-zero dark state in simulated low-light formation flight scenarios using a monochrome green HMD. Observer performance was evaluated at several different dark state luminance levels for tasks that require locating or tracking an aircraft with active navigation lights under starlight illumination. Adaptation time between relatively high and low dark state conditions was also characterized. In this paper we focus on the challenges associated with implementing the operational scenario, including calibration of both the simulation and HMD, with discussion of human performance under varying brightness conditions. These methods can be used to accurately calibrate training simulations in which highly realistic representations of low-light see-through HMD operations are a critical requirement for effective training.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 27, 2017
- Accession Number
- AD1056038
Entities
People
- Alex Van Atta
- Charles Bullock
- James Gaska
- Logan Williams
- Marc Winterbottom
- Mitchell Bauer
- Steven Hadley
Organizations
- United States Air Force School of Aerospace Medicine