Characteristics Of Fluorescent Lamps Research Articles

ガラス管の組成が蛍光ランプの特性に及ぼす影響

ガラス管の組成が蛍光ランプの特性に及ぼす影響

Characteristics of fluorescent lamps under abnormal system voltage conditions

Different types of fluorescent lamps (FLs) play an important role in lighting, since they can provide significant energy saving and last longer than incandescent lamps. However, although the voltage waveform of electrical power source is considered to be purely sinusoidal and nominal at the stage of the lamp circuit design, there appear to be ever-increasing system voltage problems of amplitude variation and harmonic distortion. It is therefore important to realize the effects on the performances of different FLs under abnormal system voltage conditions. In this paper, tests were conducted on a developed harmonic generating system to identify the electrical and illumination characteristics of two popular types of FL. The characteristics of interest include active power, power factor, current harmonic distortion and illumination efficiency index (Lux W −1). The tested results are proposed and discussed.

光源の異なる分光特性が明るさ知覚に及ぼす影響

光源の異なる分光特性が明るさ知覚に及ぼす影響

蛍光ランプの色温度・演色性が室内雰囲気に及ぼす影響

蛍光ランプの色温度・演色性が室内雰囲気に及ぼす影響

蛍光ランプ用蛍光体の帯電傾向とランプ諸特性

蛍光ランプ用蛍光体の帯電傾向とランプ諸特性

Characteristics of Fluorescent Lamps in Direct Current Operation under High Ambient-Temperature Condition.

Characteristics of a fluorescent lamp in direct current operation under high ambient-temperature conditions are investigated for application to the back-light system. It is shown that the problems relating to direct current operation of fluorescent lamps, which are light output reduction and short electrode life due to cataphoresis, can be solved by operating the lamp in such a high ambient-temperature obtained in closed fixtures of back-light systems. When the wall temperature was kept to be approximately 80°C, the total light output was approximately 6% higher in direct current operation than in alternate current operation. This may be due to the fact that the mercury atom density in the positive column is closer to the optimum value in direct current operation than in alternate current operation, when the lamp is operated in high ambient-temperature. The electrode life in direct current operation is as long as that in alternate current operation. The high mercury atom density in the cathode region due to cataphoresis may be effective to improve electrode life because of reducing cathode fall voltage.

Improving the spectral characteristics of fluorescent lamps by using narrow-band phosphors

The spectral power distributions of fluorescent lamps using red, green and blue narrow-band phosphors can be calculated by empirical equations. Quantitative relations between the combination of phosphors and the spectral power distributions of the phosphors are obtained, and the relative quantities of the red, green and blue phosphors used to produce fluorescent lamps of high luminous efficacy and colour rendering index at any given colour temperature can be derived from these relations. Experimental results coincide quite well with calculated values.

アマルガム封入蛍光ランプの立上り特性

アマルガム封入蛍光ランプの立上り特性

Model equation characteristics of high-frequency fluorescent lamps

In analysing the operating model equation characteristics of fluorescent lamps it is necessary to use the model equations of equivalent conductance of the lamps on high frequency. The model equations are estimated by the error-rate between the experimental waveform and the simulation waveform on high frequency operation. The method of analysis is found to be useful in predicting the model constants and the characteristics of fluorescent lamps on high frequency operation.

A simple equation for the rms volt-ampere characteristics of fluorescent lamps

This paper presents a simple non-differential equation simulating the non-linear rms volt-ampere characteristics of 36W and 40W fluorescent lamps. A mathematical approach to the problem of solving circuits containing fluorescent lamps becomes possible.

An investigation of the model constants for the fluorescent lamps with resistance ballast circuit.

The fluorescent lamp with resistance ballast circuit has been investigated at the commercial frequency 50 Hz or 60 Hz through the computer simulation. The characteristics of fluorescent lamps can be expressed by the differential model equation of equivalent conductance. The model constants of differential model equations are determined by the multiple regression method and optimized by the simplex method, which the errorrate between the experimental waveform and simulation waveform are estimated. The resistance ballast operation circuit is assumed as a simplest model circuit for operating the fluorescent lamps. There are very good correlations between the measurement values aud the simulation values, and the accurate model equations of fluorescent lamp with resistance ballast circuit are able to predict.

Characteristics of Fluorescent Lamp Using Mercury Dispenser

Introduction of mercury in tubes is essential because fluorescent lamps exploit the ultraviolet radiation emitted by mercury atoms. The method of dropping liquid mercury into the tube has been employed to charge the tube with mercury. Such present method of production is advantageous in that it aids the exhaust in during processing but is disadvantageous in that it cansel various defects in lamp quality.To eliminate such disadvantage, a manufacturing method which use a mercury dispenser such as an Hg alloy mounted around the electrodes, and releases mercury within the tube after sealing off by means of an induced current is introduced.Advantages in use of mercury dispensar are as follows;(1) the quantity of mercury to be introduced into lamp is very precise, (2) the pressure fluctuation of Argon to be introduced can be reduced. Consequently it is possible to prevent the fluctuation of lamp life and increase its average life. In addition, improvement of lumen maintenance is achieved.

Control of Mercury Vapor Pressure of Fluorescent Lamps by Indium-Mercury Amalgam

Characteristics of fluorescent lamps are influenced remarkably by mercury vapor pressure. Therefore. it is most important to control mercury vapor pressure.This paper deals with a new method and theory of vapor pressure control. Experiments are carried out with indium-mercury amalgam.As the results, mercury vapor Pressure is controlled mainly by electron current flow in the amalgam. And mercury vapor pressure of steady state lamps is decided by the correlation of amalgam and the coolest spot in the bulb wall. Light output-vs-ambient temperature curve becomes broader by the combination of this method and temperature compensating elements.

Measurements of Electrical Characteristics of Fluorescent Lamps

The connection of electrical measuring instruments in circuit with a fluorescent lamp usually alters its electrical and photometric characteristics. The nature and magnitude of these effects have been studied and a new method is described for determining the charactcristics which the lamp would have if there were no measuring instiuments in circuit.

Some Characteristics of Fluorescent Lamp by Temperature on the Tube Wall

Sometimes, we have experienced that the fluorescent lamp did'nt start or kept its discharge in the winter morning.From this point of view, we have experimented about some fluorescent lamps, which have a different Argon pressure, from 60°C, to-40°C, and have got two results as follows.(1) We have found the interesting relation between tube voltage and tube current by the variation of temperature as shown in figui e 6. We must of necessity observe the minimum of tube current and the maximum of tube voltage. But, there are some curves which fall down as shown in figure 14, this is because it's sparking voltage become higher than maximum value of Souice voltage at low temperature.(2) If we only think about starting voltage and the keeping of discharge at low temperature, we should take the Argon pressure lower than present nominal Value in the case of 20W lamp. But, as a matter of fact, we must take all other factors into the determination of Argon pressure, such as the life, the efficency, etc.

Low Temerature Performance of Fluorescent Lamps

The characteristics of fluorescent lamps are affected by the ambient temperature, especially so in view of performance at the low temperatnre. We shall briefly report on it as follow.The effect of the ambient temperature on fluorescent lamps is caused by the vapour pressure of mercury. As the ambient temperature goes down, the vapour pressure of mercury drops, while lamp current curve has a part of valley. When the temperature further goes down, lamp current rises again, and comes to the saturation. In other words, in proportion to fall of ambient temperature, vapour of mercury decreases and the lamp current goes down. At a part of valley vapour of mercury extremely decreases and the main discharge moves from the discharge in mercury to that in argon. Almost of mercury vapour disappears and the main discharge moves completly to that in argon. This is the state of saturation.So temperature performance of fluorescent lamps means the change of discharge in two gas particles throngh 3 processes as shown Fig. 7 of the text. This fact can be electrically and optically proved and is concluded as follows.I-the discharge in mercury only.II-the discharge in both mercury and argon under the condition that the discharge in mercury is moving to that in argon.III-the discharge in argon only.