Research on Color Luminance Ratio Design of Architectural Accessible Signs (original) (raw)

Luminance Requirements for Lighted Signage

Light-emitting diode (LED) technology is presently targeted to displace traditional light sources in backlighted signage. The literature shows that brightness and contrast are perhaps the two most important elements of a sign that determine its attention-getting capabilities and its legibility. Presently, there are no luminance standards for signage, and the practice of developing brighter signs to compete with signs in adjacent businesses is becoming more commonplace. Sign luminances in such cases may far exceed what people usually need for identifying and reading a sign. Furthermore, the practice of higher sign luminance than needed has many negative consequences, including higher energy use and light pollution.

Brief Communication: Impact of Sign Panel Luminance on Visual Comfort

Interdisciplinary Journal of Signage and Wayfinding

Signs should produce useful visual information to road and sidewalk users without creating undue glare or visual distraction. In order to assist in navigation and wayfinding, signs must be sufficiently conspicuous. For this reason their brightnesses are often higher than the surrounding visual environment. However, if the brightness becomes too high, the sign risks contributing to visual discomfort. Several published recommendations for limiting sign brightness include limits on the maximum illuminance from the sign (in lux). There is evidence, however, that the maximum luminance of a light source can also influence visual comfort. To investigate the potential role of maximum luminance, a pilot study was carried out to assess visual responses to sign panels producing the same illuminance but differing in luminance.

Evaluation of Visual Performance Using LED Signboards under Different Ambient Conditions

Procedia Engineering, 2012

This research aimed to study how to make the light emitting diode (LED) signboards be more legible under high illuminative conditions and to avoid the observers feeling dazzling glare under low illuminative conditions. This research firstly studied the literatures to explore the drivers' visual ergonomic as well as the optical properties of LED, and investigated the relatively existing norms for engineering vehicle LED signboards. Three variables were set in this study: three kinds of ambient condition, four kinds of luminance contrast and two kinds of character form. In the first phase of the experiment, subjects observed LED signboards in both near and distant locations and filled out the SWN scale (Subjective Well-being under Neuroleptics), and in the second phase, subjects were then asked to moved forward and recorded their perceptions of comfort and glare to distance range. The findings demonstrated that, there was no variation in subjective evaluation to display signs with no backgrounds either in the near or distant locations, while to display signs with backgrounds, the subjects perceptions were the farther the distance, the clearer the legibility; higher ambient illumination could effectively reduce observers' glare perception to LED signboards; signboards with backgrounds at the luminance contrast of 3:1 (L max = 3100, L min = 1033 cd / ㎡) showed the lowest uncomfortable and glare level to observers. The two forms of character showed no significant variation in affecting observers in terms of the comfort and glare perception.

A Colour Contrast Assessment System: Design for People with Visual Impairment

Visually Impaired People (VIP) encounter difficulties with the perception of products and environments in their everyday life such as a door in a wall or a column on a station concourse. Contrast can be an essential and vital aid for negotiating the world for people with low vision (Bright et al., 1997; Dalke et al., 2004b). The development of a colour contrast assessment system would enable the construction and design sectors to create more accessible spaces and objects.

Evaluation of light-emitting diodes for signage applications

2004

This paper outlines two parts of a study designed to evaluate the use of light-emitting diodes (LEDs) in channel-letter signs. The first part of the study evaluated the system performance of red LED signs and white LED signs against reference neon and cold-cathode signs. The results show a large difference between the actual performance and potential savings from red and white LEDs. Depending on the configuration, a red LED sign could use 20% to 60% less power than a neon sign at the same light output. The light output of the brightest white LED sign tested was 15% lower than the cold-cathode reference, but its power was 53% higher. It appears from this study that the most efficient white LED system is still 40% less efficient than the cold-cathode system tested. One area that offers a great potential for further energy savings is the acrylic diffuser of the signs. The acrylic diffusers measured absorb between 60% and 66% of the light output produced by the sign.

Title: Nighttime Photometric Evaluation of Unlighted Overhead Guide Signs

Overhead guide signs fabricated from four different retroreflective sheeting material combinations were photometrically (luminance and luminance contrast ratio) evaluated under low beam illumination at selected approach distances from 100 ft (30.5 m) to 1000 ft (305 m) using a 1984 Peterbilt Truck, a 2002 Chrysler Town and Country Minivan and a 2002 Toyota Camry, both with illumination by external luminaires ("lighted") and without illumination ("unlighted"). The photometric measurements were made with a ProMetric CCD Light and Color Measurement System. The luminance and luminance contrast ratio results indicate that under low beam illumination the Type VII legend on beaded Type III background sheeting material combination provides superior luminances and luminance contrast ratios for approach distances of 400 feet (122 m) or more while the Type IX legend on beaded Type III background sheeting material combination provides superior luminances and luminance contrast ratios for approach distances of less than 400 ft (122 m). For the three vehicles used, the legend luminances for the signs illuminated with luminaires and the automobile low beams are considerably higher, but have usually lower luminance contrast ratios when compared to the unlighted signs (for Type VII and Type IX legends on beaded Type III backgrounds). For instance, at 600 ft (183 m) the legend luminances for Type VII and Type IX legends on beaded Type III backgrounds range from 17 cd/m 2 to 57cd/m 2 when the signs are lighted and range from 4cd/m 2 to11cd/m 2 when the signs are unlighted and the luminance contrast ratios range from 4.2 to 9.4 when the signs are lighted and range from 4.3 to12.2 when the signs are unlighted which indicates that the legend luminances of lighted signs are 4-5 times higher, but have about up to 30% lower luminance contrast ratios when compared to the unlighted signs. Based on the results of the photometric evaluation and a separate expert panel field evaluation we conclude that unlighted overhead signs with either white Type VII or Type IX legends on green beaded Type III backgrounds provide adequate appearance, conspicuity, and legibility without sign luminaires.

Factors Affecting Sign Visibility, Conspicuity, and Legibility: Review and Annotated Bibliography

Interdisciplinary Journal of Signage and Wayfinding

This paper summarizes published research studies, technical reports and codes and standards related to the visibility (i.e., conspicuity and legibility) of signage. In the summary that follows, publications are grouped and discussed according to several different topics. First, the typographic and symbolic characteristics of signs and the information they carry are described (e.g., letter size, font selection, etc.); second, photometric, colorimetric and temporal properties of signs as they affect visibility; finally, environmental considerations (e.g., daytime versus nighttime viewing, whether a sign is located in a rural or urban area, etc.) as they influence sign design are reviewed. Annotated summaries of each publication in the literature review are included at the end of this paper.

Effect of use of color on perception: example of entrance area in healthcare buildings

International Journal of Academic Research, 2013

Planning and design of hospitals, among the healthcare institutions providing diagnosis, treatment and care services, is critically important for users and regarding the comfort conditions provided to users. With the spread of private healthcare services, changes experienced in healthcare sector has contributed in more attentive designs in healthcare buildings. Particularly, sensitivity on the colors used in interior design has increased. The reason is, colors play a significant role in hospitals, both in increasing employer efficiency and also in ensuring psycho-social and visual comfort of patients and patient relatives. The purpose of this study is to measure the admiration levels for the color preferences in entrance areas of healthcare facilities serving as private hospitals, according to the place these colors are used, and to reveal the sensitivities regarding this issue.

A Study of Vision Ergonomic of LED Display Signs on Different Environment Illuminance

Lecture Notes in Computer Science, 2011

The LED (light emitting diode, also referred to as LED) have already been used widely. However, despite the high visibility of LED with high brightness performance, it also leads to a glare problem, which generates a direct security issue in applying to traffics. Therefore, this research aimed to study how to make the LED display sign be more legible under high illuminative environments and to avoid the observers feeling dazzling glare under low illuminative environments. This research firstly studied the literatures to explore the drivers' visual ergonomic as well as the optical properties of LED, and investigated the relatively existing norms for engineering vehicle LED display signs. Three variables were set in this study: three kinds of ambient illumination, four kinds of luminance contrast and two kinds of character form. In the first phase of the experiment, subjects observed LED display signs in both near and distant locations and filled out the SWN scale (Subjective Well-being under Neuroleptics), and in the second phase, subjects were then asked to moved forward and recorded their perceptions of comfort and glare to distance range. The findings demonstrated that, there was no variation in subjective evaluation to display signs with no backgrounds either in the near or distant locations, while to display signs with backgrounds, the subjects perceptions were the farther the distance, the clearer the legibility; higher ambient illumination could effectively reduce observers' glare perception to LED display signs; display signs with backgrounds at the luminance contrast of 3:1 (L max = 3100, L min = 1033 cd / ㎡) showed the lowest uncomfortable and glare level to observers. The two forms of character showed no significant variation in affecting observers in terms of the comfort and glare perception.

Architecture Lighting Design for visually impaired people

My area of interest is the lighting sense for visually impaired people. I find that lighting design disciplines is not considered enough for those who are visually impaired, especially for blind people. This is because to most sighted people, even some lighting professors believe that since blind people can't see anything, light has nothing to do with them. They simply ignore this visually impaired group when they are considering lighting design. However, according to my research, this is wrong. Light, both daylight and electric light, are important to visually impaired people. Firstly, there are different scales of blindness. Only 6-8% of the legally blind are totally blind. Most of the blind people has some sense of light. Secondly, light can play with other senses, such as sound and smell to help them understand about the sequence of a space. Thirdly, light always comes together with heat, because of the wave–particle duality essential to Light. The other senses of blind people are stronger than sighted people, such as the sense of feel heat. Fourthly, light is fundamentally important to keeping the 24 hour cycle of people no matter if they are blind or not. Lastly, blind people share a space with sighted people, light can help them interact socially with each other. At the same time, it will be dangerous if a sighted person can't see blind people clearly in a space. To me, I don’t want to consider only visually impaired people, but to consider how to bring those who are visually impaired into public space by lighting. Lighting can help visually impaired people better understand a space, find their ways easier, and communicate with others.