High color rendering index (CRI) has been obtained from mercury-free ICP’s lamp. Due to the strong demand on the development of mercury-free light sources, the authors investigated xenon and CO as an alternative element. These rare (Xe) and molecule (CO) gases have been used as a substitute for mercury as the environmental problems related necessitate the development of new type of light sources. The target of this study is to develop a new type of mercury-free lamp without using a phosphor where the authors concentrate on how to obtain a strong visible light instead of UV. In this paper, the colors, luminance and emission characteristics of these types of mercury-free ICP’s lamp is discussed. Without the use of phosphor, the authors obtained a good color rendering from xenon and CO ICP’s lamp where their CRI’s above 90. A strong continuum emission in visible region is obtained where luminance are ranged from 2000 to 25000 cd/m² at 100 W of input power. Spectral distribution shows the continuum emissions are similar to the daylight distribution and chromaticity diagrams shows they are close to white region in color coordinates and color temperatures bringing a high index of the lamp’s color rendering.

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In this article the obtained results of refractive index, by laser interferometer method, of Carbon Dioxide, CO₂, molecule were used to determine the physical parameters of this pollutant gas. Because the existence of this gas in the atmosphere under the effect of the atmospheric changes like as pressure, temperature and sun light. These atmospheric changes change the behavior of this pollutant gas according to the change of its physical parameters which tends to more destructive effects on the biological cells. Optical permittivity ε, dielectric susceptibility k_e, specific refractivity A_sp, and molar refractivity Π were determined. The effect of temperature T[K], within the available technical range 308K-358K, on these physical parameters was studied which was known as thermal behavior. The rate of change of these parameters with respect to temperature at constant gas pressure p and incident laser wavelength λ such as (dε/dT)_p,λ; (dk_e/dT)_p,λ; (dA_sp/dT)_p,λ; and (dΠ/dT)_p,λ were studied showing negative slope values which mean an inverse dependence of ε, k_e, A_sp, and Π respectively. Also, the rate of change of those parameters with respect pressure range 80×10³-120×10³Pa at constant temperature and laser wavelength, (dε/dp)_T,λ; (dk_e/dp)_T,λ; (dA_sp/dp)_T,λ; and (dΠ/dp)_T,λ were investigated showing direct proportionality between these parameters and pressure. In addition, the dispersion of these physical parameters, rate of their change with respect to λ, four different selected wavelength, at constant T and p of CO₂-gas to be (dε/dλ)_T,p; (dk_e/dλ)_T,p; (dA_sp/dλ)_T,p; and (dΠ/dλ)_T,p were studied representing inverse dependence of these parameters on λ. The behavior investigations of these physical parameters consider as an index for environmental air pollution investigations.

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In present work a polyvinyl pyrrolidone (PVP) polymer was selected to study the phenomena of optical laser light scattering (OLLS). PVP was investigated for its importance in the daily industrial applications which are important for different branches. This polymer was solved in different solvents like as Methanol, Chloroform and Dimethylformamide, DMF, with different concentrations 1, 2, 3, 4, 5, 6 × 10^-3 g/ml. The refractive index increments (dn/dc) of that polymer solution were determined with the aid of an constructed laser interferometer system. The obtained values of dn/dc were used in the laser scattering investigation. OLLS data were obtained by using a self-built of laser scattering system. The angular behavior of that selected polymer solution with different concentrations were studied by plotting the intensity of the scattered light against the scattering angle. The value of kc/R(θ) ratio was plotted as a function of θ through the value sin²(θ/2)+100 C, showing what was called Zimm plot. From that plot the different scattering parameters such as Pap’s molecular weight M_w, Second virial coefficient A₂, Radius of gyration R_G and molecular radius D of that polymer were determined in that three different selected solvents. These obtained values of scattering parameters can be used to investigate the random laser (RL) phenomena in addition to the industrial and Pharmaceutical applications of PVP.

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This study investigated how focusing light on different elements of a scene affects the stress-alleviating, restorative experience. Three night time scenes were created with the Lightscape computer program. Each scene was illuminated in two different ways, one focusing light on roads and parking lots and the other on vegetation, resulting altogether in six views. It was expected that focusing light on vegetation would result in higher ratings of restorative experience. The simulated views were rated by 35 participants using the Perceived Restorativeness Scale (PRS) and the Restoration Outcome Scale (ROS). In accordance with our hypothesis, focusing light towards greenery vs. parking lots and roads resulted in higher PRS and ROS ratings. The results suggest that lighting offers considerable potential for enhancing the restorativeness of urban night time environments.

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Aiming at rigorous evaluation of a semi-infinitely long circular blackbody cavity, which is also a representative element of micro-cavity or carbon-nano-tube (CNT) array radiator, we propose that the series solution of the integral equation for the effective emissivity at the interior of the circular cavity should be reduced to an explicit form only with wall reflectivity. Applying that, we can get enough accuracy of calculating the effective emissivity with the approximation in the 2nd power of wall reflectivity.

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This report was presented as an invited speech at “the First Lighting Symposium of China, Japan and Korea” held in Beijing on October 24, 2008. The reporter has introduced JELMA's proposal for energy saving in lighting, and explained purpose of their activities. Latest activities for replacing incandescent lamps to CFLi and its recent results are also reported. Japanese next big target for lighting energy saving is to replace the conventional fluorescent lamps to Hf-FLs.

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