72 research outputs found
High dynamic range display systems
High contrast ratio (CR) enables a display system to faithfully reproduce the real objects. However, achieving high contrast, especially high ambient contrast (ACR), is a challenging task. In this dissertation, two display systems with high CR are discussed: high ACR augmented reality (AR) display and high dynamic range (HDR) display. For an AR display, we improved its ACR by incorporating a tunable transmittance liquid crystal (LC) film. The film has high tunable transmittance range, fast response time, and is fail-safe. To reduce the weight and size of a display system, we proposed a functional reflective polarizer, which can also help people with color vision deficiency. As for the HDR display, we improved all three aspects of the hardware requirements: contrast ratio, color gamut and bit-depth. By stacking two liquid crystal display (LCD) panels together, we have achieved CR over one million to one, 14-bit depth with 5V operation voltage, and pixel-by-pixel local dimming. To widen color gamut, both photoluminescent and electroluminescent quantum dots (QDs) have been investigated. Our analysis shows that with QD approach, it is possible to achieve over 90% of the Rec. 2020 color gamut for a HDR display. Another goal of an HDR display is to achieve the 12-bit perceptual quantizer (PQ) curve covering from 0 to 10,000 nits. Our experimental results indicate that this is difficult with a single LCD panel because of the sluggish response time. To overcome this challenge, we proposed a method to drive the light emitting diode (LED) backlight and the LCD panel simultaneously. Besides relatively fast response time, this approach can also mitigate the imaging noise. Finally yet importantly, we improved the display pipeline by using a HDR gamut mapping approach to display HDR contents adaptively based on display specifications. A psychophysical experiment was conducted to determine the display requirements
A Compressive Multi-Mode Superresolution Display
Compressive displays are an emerging technology exploring the co-design of
new optical device configurations and compressive computation. Previously,
research has shown how to improve the dynamic range of displays and facilitate
high-quality light field or glasses-free 3D image synthesis. In this paper, we
introduce a new multi-mode compressive display architecture that supports
switching between 3D and high dynamic range (HDR) modes as well as a new
super-resolution mode. The proposed hardware consists of readily-available
components and is driven by a novel splitting algorithm that computes the pixel
states from a target high-resolution image. In effect, the display pixels
present a compressed representation of the target image that is perceived as a
single, high resolution image.Comment: Technical repor
The Impact of Distance on the Accuracy of Luminance Measurement
AbstractMany researchers want to reduce the severe luminance difference caused by artificial lights or natural lighting and when luminance is highly uniform. This paper focused on the correlation between measured luminance and the distance of measurement from the light source. For this task, two types of luminance measuring methods were adopted. Namely, High Dynamic Range (HDR) image processing and CS-100 instrument for measuring surface luminance and point luminance respectively. The results indicate that there was a 3% decrease in measured luminance as the distance from the light source was increased by 1m
Serious Games in Cultural Heritage
Although the widespread use of gaming for leisure purposes has been well documented, the use of games to support cultural heritage purposes, such as historical teaching and learning, or for enhancing museum visits, has been less well considered. The state-of-the-art in serious game technology is identical to that of the state-of-the-art in entertainment games technology. As a result the field of serious heritage games concerns itself with recent advances in computer games, real-time computer graphics, virtual and augmented reality and artificial intelligence. On the other hand, the main strengths of serious gaming applications may be generalised as being in the areas of communication, visual expression of information, collaboration mechanisms, interactivity and entertainment. In this report, we will focus on the state-of-the-art with respect to the theories, methods and technologies used in serious heritage games. We provide an overview of existing literature of relevance to the domain, discuss the strengths and weaknesses of the described methods and point out unsolved problems and challenges. In addition, several case studies illustrating the application of methods and technologies used in cultural heritage are presented
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