The purpose of this paper was to investigate how the initial adaptation level and the elapsed time affected proper illuminance for relaxation. The experiment carried out three lighting patterns which changed the placement and the shape of the lamp. Ten females aged 21 to 25 were the subjects. In the experiment the initial adaptation levels were set to 20 lx and 150 lx as defined by the horizontal illuminance in the center of the floor. The subject adjusted the illuminance to get the best relaxation situation and evaluated the degree of satisfaction after two minutes when the subject entered the evaluation room, and repeated the same adjustment and evaluation after five minutes, nine minutes, 17 minutes, and 32 minutes. In the first nine minutes, there were the remarkable changes in the illuminance for relaxation and the satisfaction but after nine minutes there weren't many changes. The proper illuminance made by the subject after 32 minutes was different depending on whether the initial adaptation level was 20 lx or it was 150 lx. The effect of the initial adaptation level was compatible with the elapsed time. Furthermore the illuminance level for relaxation obtained in this research was lower than the results of other researches. In conclusion, the initial adaptation level and the elapsed time affect the illuminance and evaluations of satisfaction and therefore it is necessary to take them into consideration when studying lighting conditions and using the investigation results for lighting design.
Photometric stereo method can be used to find the orientation of the surface of an object to be measured. This method cannot avoid the influence of highlights in an image that are caused by the specular reflection components of mixed diffuse-specular objects. In a previous paper, we presented that estimate luminance distribution in highlight regions can eliminate influence of highlights in an image. However, the previous method is unstable when some highlight regions overlap. We have proposed a new method of measuring the shapes of mixed diffuse-specular objects. First, highlight is detected using the bi-directional reflectance distribution function. Next, highlight regions that overlap in a gray-level image are divided using the watershed algorithm. Then, the luminance distribution caused by the diffuse reflection components in the highlight regions is estimated based on the luminance distribution in a gray-level image without highlights. Shape measurement experiments using mixed diffuse-specular objects with different characteristic reflectances and shapes showed that our method can accurately measure the 3-D shape of mixed diffuse-specular objects.
The effects of performing a visual task and/or conversation task on a functional visual field (FVF) on a dynamic background simulating a driving situation were experimentally studied. A red or pink circular target was briefly presented somewhere on a movie scene depicting driver's view, and the observer's task was to indicate the target's position. The visual task loaded on the observer was to read out two alphabet letters presented at the center of the visual field. The conversation task was to answer to an easy question orally. The FVF narrowed with the visual task as well as with the conversation task, while it markedly shrunk when both visual and conversation tasks were imposed simultaneously.
Super high pressure mercury discharge lamps have been used as a UV and visible light sources for photolithography exposure process, such as patterning LCDs, PCBs and semiconductors. This study examines their rupture characteristics and discuss a guideline for designing a part of lamp between the end of bulb and the end of the sealed part under internal pressure. Finite-Element method (FEM) was employed to investigate the maximum principal stress σ1 distribution near the end of the sealed part. Furthermore, static water pressure tests were conducted to examine the strength characteristic of the bulbs. As the results, the rupture characteristics near the end of the sealed parts can be elucidated and the guideline for designing the end of the sealed parts were drawn up. Moreover, the relationships among the rupture pressure and the outer diameter D2 of the glass parts in the sealed parts and the length L1 near the end of the sealed parts were obtained for increasing the bulb strength. It was found that the strength near the end of the bulb was increased as the diameter D2 was decreased and the length L1 was increased. The rupture characteristics obtained by the numerical results were in fairly good agreements with those by the experiments.