Theoretical and experimental investigations on the absolute measurement of Raman scattering cross sections are reviewed. A newly developed method by the present authors has been proved to give the over all accuracy of 3.5%, which is the highest accuracy ever been attained. The measurements by the excitation of the 6328Å, 5145Å, and 4880Å laser lines give the frequency dependence of the cross sections, which shows a qualitative agreement with what is expected from theoretical arguments.
The process of measurement on the scaler which has developed in the fields of radiation measurement and instrumental analysis do not posess the function of calculation. But the pro-cess may be made to have a calculating function by means of dividing the scaler into three parts, namely, (1) counting groups (same decimal calculating counter groups), (2) counting and calculating control (control circuits) and (3) calculating program (program circuits), and if the four rules of calculation are possible mutually between exactly the same decimal calcula-ting counters, a calculation on the data processing will be possible also. In this paper, the orders for the four rules of calculation, the construction of a decimal calculating counter and the results of high stability and reliability on the operational test are reported.
Transient behavior of organic dye lasers was studied by analysis of rate equations. At first, I clarified the “spiking” condition of dye lasers with small signal approximation of rate equations and, as the result, showed that dye lasers were generally operated near the critical region between spiking and non-spiking. And then, it was ascertained that “quasi-steady state” approximation of rate equations was accurate enough when the exitation was strong, and by means of this approximation, the formulas of output peak power, reflectivity at optimum coupling, and energy conversion efficiency, were obtained.
In this paper the results of investigation of the radiation waveforms and the temperature dependence of light intensity with direct current bias of thin evaporated films of ZnS; Cu, Mn, Cl phosphors are reported. Equations relating the brightness (B) with voltage, current and power of direct current electroluminescence (D. C. E. L) are obtained. The brightness was strongly dependent on the total current through the sandwich type cell and showed a linear relationship to power, and hence we may conclude that the efficiency of the E. L. cell remains constant. Equations for brightness may be expressed as follows: B=A1 exp (-c1/√V) at room temperature, B=A2T2 exp (-c2/T) above 250°K. Here V is the applied voltage, T is the absolute temperature of the cell, and A1, A2, C1, C2 are constants. It is seen that (B) is practically independent of T at low temperatures. From these results, it is considered that the excitation mechanism of D. C. E. L can be explained by the tunneling effect of electrons at low temperatures, whereas at high temperatures the effect of Schottky emission must be considered. It was also found that the direct excitation of Mn center due to the electrons injected into phosphor film from the negative electrode are responsible for the E. L. effect of the film.
The temperature distribution around a hot wire was obtained by the measurement of interference fringe deviations observed in a Michelson interferometer. A new method was devised to calculate the temperature distribution mentioned above numerically, in which the temperature distribution is appro-ximated by superposing a number of straight lines. The temperature distribution obtained experimentally was compared with that of the solution of the equation of heat conduction, and a fairy good agreement was found.
The energy distribution of output electrons -from a channel. electron multiplier was calcu-lated theoretically using Yakobson's theory for gain characteristics of channel electron multiplier. Calculated result indicates that the output electrons have a considerable quan-tity of high energy component. It is also found that direct information concerning mean collision length of electron in the channel can be obtained from the energy distribution curve.