David L. Post

Further evaluation of methods for producing desired colors on CRT monitors

Three experiments were performed to evaluate methods for predicting the luminances and chromaticity coordinates produced by color CRT monitors, given known inputs. Linear and logarithmic versions of PLCC and PLVC, plus Berns, Motta, and Gorzynskis power function, were tested. Estimates are provided for the number of CRT measurement points needed to maximize each methods predictive accuracy. Correcting for unintended light from the monitor is shown to improve accuracy substantially for a case involving a seemingly small amount of light. Berns et al.s characterization technique, which involves measuring the monitors neutral point, is shown to yield the same accuracy as conventional characterization while reducing the number of measurements required, and to yield improved accuracy when correction for unintended light is needed but impractical. The accuracies of the predictive methods are compared and recommendations for their use are provided.

Benefits of Color Coding Weapons Symbology for an Airborne Helmet-Mounted Display

We assessed the advantages of a color-coded weapons symbology for a helmetmounted display over monochrome symbology by measuring military pilots performance while they flew air-to-air combat in a simulator. The pilots fired missiles significantly sooner without sacrificing probability of kill when using the color coded symbology, demonstrating a substantial practical benefit of color. Actual or potential applications of this work include the design of color codes for helmetmounted and other displays that use complex symbology to assist performance on cognitively challenging tasks.

Applied Color-Vision Research

Most of us recognize from personal experience that, when they are designed properly, multicolor displays are not only more pleasing aesthetically than monochrome displays, but also convey more information and/or do so at higher rates. (Perhaps this is why they are more pleasing.) The catch is that color must be used “properly”; therefore, much of the applied color-vision research that has been performed has been directed toward increasing our understanding of how to do this. This chapter reviews some of the topics that have attracted special interest and, where it is appropriate, makes recommendations based upon the research findings.

Image quality of two-primary color active-matrix liquid-crystal displays

The demand for color head- and helmet-mounted displays (HMDs) is growing. Interest focuses on full-color systems, but a limited color repertoire is sufficient for some applications and can reduce cost and complexity significantly, especially when subtractive-color active-matrix liquid-crystal display (AMLCD) technology is used. We report a series of experiments that investigated important questions about the design and merits of two-primary color AMLCDs for HMD applications. Our main conclusion is that the image quality of a subtractive-color AMLCD with high (≥70%) aperture ratio is superior to a comparable, conventional color AMLCD. Evidence regarding requirements for resolution, aperture ratio, and gray scale is also provided.

Predicting color breakup on field-sequential displays

The quest for color head- and helmet-mounted displays has led some designers to consider the use of field-sequential color (FSC) because it offers higher resolution than conventional color displays in a compact package. Unfortunately, FSC displays exhibit color breakup sometimes, and the viewing conditions under which this occurs have not been established very well. We performed an experiment to determine color-breakup thresholds for a simple FSC stimulus as a function of stimulus luminance, contrast, and retinal velocity. We developed equations that describe the results and can be used to predict whether color breakup will be visible for specified viewing conditions.

Color and Human-Computer Interaction

Publisher Summary The software industry has taken advantage of the wide availability of color displays and increasing availability of color hardcopy equipment by using color in its products. The general problem of using color in an effective and attractive manner to enhance human-computer interaction (HCI) is no longer germane to only a few specialized applications—it is a problem faced by a substantial portion of the entire computing industry. This chapter treats color-related topics that are relevant to HCI. It begins with the discussion of the basics of color vision, while also introducing Commission Internationale de I Eclairage (CIE) photometry and colorimetry, respectively, which are the bases for nearly all quantitative approaches to color. Further, this chapter covers alternatives to the CIE uniform color spaces that are especially relevant to computing. The chapter also explains equipment and procedures for measuring color.

Colorimetric Measurement, Calibration, and Characterization of Self-Luminous Displays

This chapter discusses methods and equipment for measuring, calibrating, and characterizing the color of self-luminous color displays. The basic measurement methodology that is used almost universally today is that which was introduced as the international standard by the CIE in 1931. Since that time, the CIE has made occasional, minor modifications that have necessitated periodic revisions in its published recommendations. Currently, the authoritative reference is CIE (1986). Calibration and characterization techniques, on the other hand, are not well standardized at the moment. Although some conventions exist, the development of proper procedures is still the subject of both debate and research.

An Evaluation of Methods for Producing Specific Colors on CRTs

Experiments were performed to evaluate several methods for generating colors having specific CIE chromaticity coordinates and luminances on a CRT. The methods accuracies are characterized and avenues for improvement are suggested.

Colour display gamuts and ambient illumination

Abstract Researchers and designers who work with self-luminous colour displays often draw figures to show the colours that their displays can produce. The production and interpretation of such figures involve nuances that are not always understood and, particularly in cases involving ambient illumination, therefore lead sometimes to erroneous conclusions. This paper offers a brief tutorial, discusses some of the subtleties that arise, and introduces terminology to clarify those subtleties.

Human factors of two-primary-color AMLCDs

Demand for color head- and helmet-mounted displays (HMDs) is growing. Interest focuses on full-color systems, but a limited color repertoire is sufficient for some applications and can reduce cost and complexity significantly, especially when implemented using subtractive-color active-matrix liquid-crystal display (AMLCD) technology. Recently, Honeywell completed an extensive series of human factors experiments to answer important questions about the design and merits of two-primary subtractive-color AMLCDs for HMD applications. Our main conclusion is that a subtractive-color AMLCD with high aperture ratio should yield better image quality than a comparable spatially integrative AMLCD. Making use of a two-primary displays ability to produce mixture colors (e.g., yellow and orange) could also prove beneficial. This paper summarizes the experiments and findings that lead to these and other conclusions.