Fluorescent lamp luminaires with multilayer polarizer panels produce partially polarized light*, which can increase the contrast of a visual task under some viewing conditions. In principle, a decrease in illuminance can accompany an increase in task contrast without affecting visual performance. Because a reduction in illuminance implies a reduction in the electric power used for lighting, mul...

This reserch proposes a method to provide an appropriate illuminance and color temperature in an office lighting environment for individual workers. For the control algorithm, based on the optimization method called Simulated Annealing (SA), a method including a neighborhood design mechanism for the design variables instead of a temperature parameter was used. In addition, for changes in the lu...

The NIST candela is maintained via standard photometers which have shown long-term stability better than 0.1% per year. The detector-based method has allowed us to reduce the uncertainties of calibrations and to expand the range of calibration capabilities. There have been several new developments in photometry at NIST. A high-illuminance calibration facility has been developed. Four temperatur...

In the present study we investigate the dependence of photopic contrast thresholds on retinal illuminance in infants and adults. Contrast thresholds were measured at five retinal illuminances between about 6 and about 20,000 Td in subjects in both age groups. The forced-choice preferential looking technique was used in 3-month-old infants, and standard forced-choice techniques were used in adul...

PURPOSE In this work, we investigated the pupillary conditions during straylight measurement, and the potential effect this might have on the measured straylight. METHODS Five young (26-29-years-old) and 15 older (50-68-years-old) individuals participated in this study. First, the pupil diameter of both eyes was measured at three room illuminances. Next, straylight was assessed at two room il...

Proper use of daylighting cannot only improve the visual comfort in indoor environment, but also reduce building energy consumption effectively. Studies on this topic have been mostly conducted for office buildings, but were limited for industrial buildings, where lighting is a major electricity consumer. This paper presents a study of daylighting performance in a large space industrial buildin...

background: carpet weaving is an occupation that requires sufficient and appropriate lighting. the lighting in carpet weaving workshops affects the productivity and the physical and mental health of workers. therefore, the evaluation of the illumination and the identification of work stations requiring lighting modifications will be helpful in promotion of the health and safety of workers in ca...

Daylight dynamic metrics provide an alternative approach for the assessment of energy savings promoted by lighting control systems. This research aims to quantify allowed smart controls using continuous and overcast daylight autonomy, novel tested monitoring a mesh illuminance-meters in test cells over one-year period. Three types are proposed, based on switches dimmers, some which were managed...

An original method is proposed to extract the most significant volumetric structures in an illuminance image. The method proceeds in three levels of organization managed by generic grouping principles: (i) from the illuminance image to a more compact representation of its contents by generic structural information extraction leading to a basic contour primitive map; (ii) grouping of the basic p...