This report describes lighting researches and results for evaluation of performance of the building environment and quality of the luminous environment. At the early stage of developing evaluation methods for the building environment, emphases were put on improvement in the indoor amenity and little regard was paid for environmental loads. Increasing global environmental issues have led to comprehensive evaluation of the building environment from both aspects of the environmental quality and load. Visibility and visual comfort have been main research topics for evaluation of quality of the luminous environment. Future research would need a shift to effects of light on human mechanisms, beyond visibility and visual comfort, and new approaches to the study.

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Assessment for luminous environment should base on appearance of things. To deal with appearance, we should analyze luminance images, and the analysis should base on the model of our visual system, which would be the multi-channel model. Therefore it would be better to adopt the contrast profile method, and to use wavelet transform for developing assessment system. The author introduces brightness image, color perception image, visibility image, and glare image for example.

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The border luminance of color appearance mode is introduced as a measure of space-brightness. Its theoretical backgrounds, protocol, experiments, characteristics, and problems are described. One of the approximate estimation of border luminance from luminance distribution, Feu, is also mentioned.

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Lighting can produce various visual impressions of lit environments. Studies on the psychological aspects of lighting have revealed, in general, that our psychological evaluation for lit environments is composed of two major factors; brightness and activity. In this article, I reviewed recent our researches for exploring quantitative methods for estimating the sense of brightness and activity for lit environments based on the spatial luminance distribution.

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Discomfort glare form a large source/windows was described. Since PGSV in which the effect of background luminance decreases with the size of the source cannot predict glare caused by total-amount effect, the glare equation using average luminance should be used together with PGSV. Image by digital camera technology can help to find the border between the source and the background in actual spaces with complicated luminance distribution. Other parameters e.g. pre-adaptation luminance should be considered.

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In general, the average illuminance calculation is used frequently for lighting planning; however, including perceived space brightness in the planning allows lighting design to take both perceived space brightness and visibility into account, which was difficult with the use of average illuminance only. This paper describes cases based on the prediction of the Feu value conducted during design time to the actual Feu measurement after spaces are completed, and reports the results of comparative studies based on the cases.

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We focused our attention on the evaluation of space brightness based on the border luminance of color appearance mode developed by Shinoda & Yamaguchi and developed space brightness index "Feu". In this paper, we explain the technical content of "Feu" from the side of application to the lighting design, and introduce the case where "Feu" is actually applied to the Lighting design.

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This paper introduces an overview and the perceived brightness evaluation results of "Personal Blind" and "lighting control based on walker movement information", which is the lighting equipment/lighting control respectively utilizing perceived brightness evaluation. It also describes the important points to be noted in perceived brightness evaluation, and the efforts in future research of perceived brightness, which the author regards as his research topic.

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This paper introduces two cases where a new light environment evaluation method was applied. The first case is an indoor luminance distribution prediction conducted with all-weather sky luminance distribution model during the design phase to evaluate the light environment under conditions which could not be covered with conventional sky model. The second case is a subject experiment using a method to evaluate the physiological and mental effects of light environments on humans. The results suggest that these methods play key roles in light environment evaluation.

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Our company developed a light environment evaluation system called QUAPIX. This system allows us to generate three types of visual psychology images through image processing of a luminance distribution image: a brightness image, a conspicuousness image, and a visibility image. This report describes eight instances of evaluation including a real space using QUAPIX. This system enables an entire present state analysis based on the amount of visual psychology, proposals for improvement, and the qualia prediction for planned facilities when used together with rendering software.

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