BACKGROUND At the entrance of a tunnel, reflection of sunlight from the surrounding environment and a lack of adequate lighting usually cause some vision problems. The purpose of this study was to perform a safety evaluation of lighting on a very long road in Ilam, Iran. METHODS The average luminance was measured using a luminance meter (model S3; Hagner, Solna, Sweden). A camera (model 108, ...

Light conditions represent an important part of every vision application. This paper describes one active behavioral scheme of one particular active vision system. This behavioral scheme enables an active system to adapt to current environmental conditions by constantly validating the amount of the reflected light using luminance meter and dynamically changed significant vision parameters. The ...

The Federal Highway Administration’s (FHWA) Turner Fairbank Highway Research Center (TFHRC) is undertaking a research program to study the visibility of retroreflective raised pavement markers (RRPMs). The focus of the initial effort is to determine the relative luminance of RRPMs and pavement markings (PMs) needed to produce adequate guidance on rural two-lane roadways at night. A driving simu...

We investigated the spatial summation effect on pedestals with difference luminance. The targets were luminance modulation defined by Gaussian functions. The size of the Gaussian spot was determined by the scale parameter (standard deviation, σ) which ranged from 0.13 to 1.04. The local luminance pedestal (2 radius) had mean luminance ranged from 2.9 to 29cd/m. The no-pedestal condition had a m...

In this paper we describe the procedure followed in photometric characterization of a DSLR camera order to implement an imaging luminance meter. The first step consisted experimental setup system obtain spectral response curves CMOS sensor for its three channels: red (R), green (G) and blue (B). Then, based on linear combination RGB channel curves, calculated approximation CIE luminous efficien...

The visibility level (VL) approach is often applied to assess the performance of vehicle lighting systems. After describing the details of the VL computational model, we review how it is ordinarily implemented for assessing night-time visibility in driving conditions. Then we present an evolution of the VL approach which consists in evaluating visible edges instead of visible objects, thereby s...

PURPOSE Cortical visual impairment (CVI) is the most common cause of bilateral vision impairment in children in Western countries. Better quantitative tools for measuring vision are needed to assess these children, to allow measurement of their visual deficit, and to monitor their response to treatment and rehabilitation. The author performed a series of experiments to assess the use of the swe...

Background & Aims of the Study: Promoting the health and safety is an important part of the fundamental mission of schools and one factor in designing and operating schools that always has been important is lighting. As students spend considerable hours in the classroom and school, lighting should be designed appropriately and in accordance with the standards, to protect them...