An attempt was made to develop a new method to measure the bactericidal irradiance (253. 7 nm) accurately based on the silicon photodiode self-calibration technique. The absolute responsivity of a silicon photodiode was determined at 632.8 nm with self-calibration technique. The absolute responsivity at 253. 7 nm of the photodiode was determined by the relative spectral responsivity measurement using a spectral responsivity standard which is a thermal detector. Pure bactericidal radiation was generated from the combination of a bactericidal lamp (GL-15) and an interference filter which has a pass-band of only around 253. 7 nm, and its irradiance was calibrated using the silicon photodiode with an aperture of known opening area. Using the calibrated radiation, any bactericidal irradiance detector can be calibrated accurately.
This paper describes the simulation results of metal halide lamp operation by using the state va riable equation model that based on the electrical conductivity of plasma, which model reported by authors. At first, the warm-up time of lamps are investigated by changing coefficient (s) in the equation, and the lamp shapes such as diameter of the arc tube, distance between electrodes and glass thickness of the tube. Next, the effect of initial vales of the state variables to the wram-upperiod are investigated on ambient temperature and preheating burning, etc. From these results, it is cleared that the rapid light standing up of metal halide lamp depend on the vaporization speed of enclosed material s, and the raising velocity of lamp temperature. And the experimental results of adjusting the lamp input power shows the possibility of shortening the warm-up time.
We have developed the computer simulation program in the design of optical multi-layers including a heat absorbing layer which are coated on the metal (Aluminum) based substrate. We have investigated the influences on the spectral reflectance on the case of changing the thickness of each layer, refractive indices and the degree of oblique incidence of light. As the result of the aforesaid, optical multi-layers including the heat absorbing layer were deposited on the substrate by the ionplating method. Then, we have manufactured mirrors which absorbs infrared radiation of about 80 percent from a lamp. Simultaneously, we have evaluated several characteristics of the optical multi-layers and confirmed that they are fit forpractical use satisfactory.
On a certain part of the ballast in the lag type operating circuit for the high pressure mercury arc lamp (H 100), a tap is made to form a by-pass circuit in order to reduce the third harmonics current caused by the third hamonics voltage may flow into the input terminal, or the side of the current where power is suplied. (1) The value of the coil and optimum capacity value of the condenser in the by-pass circuit are theoretically obtained. The following (2) and (3) are conducted with sinusoidal rated voltage impressed at the input terminal. (2) The optimum capacity value of the condenser in the by-pass circuit is obtained in the following manner: the capacity value of the condenser in the by-pass circuit is varied and the wave analysis of the voltage and current of distorted waves at each element are made, and the distortion factor of the electric current flowing in the current on the side of the power source, the effective, power, reactive power, distorted power and power factor at the power source are measured. (3) A condenser is connected in parallel with the input terminal in order to make the power factor of the fundamental current at the power source 1, and experiments are made on harmonic characteristics on the starting to consider them.
Absorption and penetration depth of infra-red radiation covering 0.8-2.5 micro-meter wave length has been established successfully in spectrographic way for city water at room temperature by means of transmittance measurements and precise analysis formulae concerned already etsablished by one of the authors. The view point of this paper is based on infra-red radiation heating of water. Special references are made to interference effects caused by forward going and successively reflected backward waves in the measured thin water film. Taking advantage of the above interference effects, water refraction index spectrum covering 0.8-2.5 micro-meter wave length has been found, and also the approximate one for 2.5-25. micro-meter has been given by means of a special reflection measurement.
Conspicuity of color changes according to illuminance because of the Purkinje shift. This makes it difficult to design safety clothes with a single color which gives always high conspicuity at any illuminance. To overcome the difficulty the combination of two colors, one being very conspicuous at day time and the other at night time, was proposed to use for the clothes. To evaluate the conspicuity throughout different illuminances the conspicuity index was introduced as the sum of the conspicuity points of a color combination at three typical illuminances, 0.1, 10 and 1000lx. The indices were experimentally determined for 12 color combinations and it was shown that they agreed quite well with those of theoretical prediction.