To study the retinal light adaptation we measured and analyzed the flicker electroretinogram response to stimuli that varied in temporal frequency, retinal illuminance, and modulation depth. The responses measured at 100% modulation showed the classic adaptation pattern, being independent of mean retinal illuminance at low temporal frequencies, consistent with Weber adaptation, and increasing i...

An intelligent lighting system which provides required illumiancne at an appropriate location is proposed. This system does not have the centralized control device and also it is controlled by each intelligent lighting’s autonomous operation. Also the intelligent lighting system can contribute to energy saving. In this research, a new algorithm is proposed. For rapid converges it uses the corre...

We have used a color-matching technique to obtain estimates of the optical density of cone photopigments as a function of retinal illuminance in patients with insulin-dependent diabetes mellitus (IDDM). We found that the half-bleach illuminance of some patients is abnormally high. That is, it takes more light to bleach an equivalent amount of photopigment in these patients. Since low illuminanc...

It has long been recognised that the lit environment in open-plan office space is influenced by the density and properties of the installed furniture. Indeed, the Lumen Method includes a procedure involving look-up tables to account for the effects of workstation size, partition height, and partition reflectance on the mean working-plane illuminance. As part of a larger project on openplan offi...

PURPOSE The slope of the rod threshold versus the illuminance (TVI) function changes with the wavelength of the background light. This study was conducted to determine whether the changes in slope are due to the stimulation of specific cone classes. METHODS An eight-channel optical system was used to generate lights that differed in cone and rod photoreceptor illuminance. Rod flicker TVI func...

We propose a color vision model that can be used to predict color appearance in mesopic vision as well as photopic and scotopic vision. It is based on a two-stage model which consists of the cone and opponent stages and it assumes rod intrusion at the opponent stage. The model has the following features to describe the color appearance in mesopic vision. First, it includes a gradual and nonline...

The National Institute of Standards and Technology (NIST) candela is maintained via standard photometers which have shown long-term stability of 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 the NIST. A high-illuminance...