The sputtering by ion bombardment, whose energy is given through the cathode fall, damages the thermionic emission on the tungsten filament. Our final purpose is to grasp the ratio of Hg-ion to the total ions. Firstly, we studied the influence of Hg on the cathode fall voltage (Vc) by comparing Ar-Hg lamps and Ar-lamps at any discharge current. Ar-Hg-lamp's Vc is lower than Ar-lamp's at 100% current. However we could not grasp the Vc on dimming because of the phase-shit of the measured plasma potential to lamp voltage. The reason is considered the distortion of the current on dimming.

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In recent years, the cathode design of a fluorescent lamp in consideration of dimming is becoming important with the energy-saving intention. In this report, with double circular fluorescent lamp 85W type, we examined the optimum dimming range by simulations and experiments. First, we guess that the cathode obtain good emission by carrying out simple modeling of the filament and by the search for the relation of current control preheated (CCP) between filament temperature. Next, by this result, we confirm the cathode in conditions 1-9. By these examinations, it was able to narrow down the optimum dimming range of the 85W type. From now on, this method will be expected as searching for dimming range of high frequency fluorescent lamps and as designing cathode in consideration of dimming.

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We are examining the indirect-heated cathode in place of the conventional cathode (direct-heated cathode) for low-pressure gas discharge lamp. This indirect-heated cathode has two structural features; first, the discharge surface electrical potential is common, second, the heat radiation area is reduced. And this indirect-heated cathode does not need heating while operating. Then we find the possibility of the indirect-heated cathode that the cathode load is small and the characteristic of life is long (For tens of thousands of hours or more) for large discharge current.

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Because of environmental preservation, we must reduce Mercury in Fluorescent Lamps, which causes damage to the environment. To reduce Mercury, we must dose Mercury precisely into lamps as much amount as we need. To achieve it, Zn-Hg pellet is more effective than originally used liquid Mercury. We searched Mercury vaporization characteristics from Zn-Hg pellet. We found that the amount of the liquid like Mercury, which has vapor pressure characteristic almost as same as liquid Mercury, is about 10% of total Mercury in the pellet. and that the liquid like Mercury is generated inside Zn-Hg pellet during burning time.

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In recent years, self-ballasted compact fluorescent lamps(SCFL's) have been downsized, then the internal electronic circuits receive greater heat stress. Here, we investigate two types of heat transfer network analyses. One is to calculate non-linear simulateneous equations and acquire the steady solutions. The other is to solve the unsteady problem by setting up initial temperatures and heat capacitors. The number of elements, each indicating a part of the lamp, is 12 for a SCFL with an outer globe.

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Demand for self-ballasted fluorescent lamps is increasing. They have a problem of their larger size than incandescent lamps. Recently the number of lighting fixtures for E17base-incandescent lamps is increasing. It is necessary for E17base-self-ballasted fluorescent lamps to adapt them. They have another problem that starting time of luminous flux is slow. We investigated their miniaturization and the improvement of their starting time. To carry out above specifications, spiral-shape arc tube wrapped at high density is for the miniaturization, and making convexity at its top and cooling down its temperature by heat conduction material are for the improvement of starting time.

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Electronic self-ballasted fluorescent lamp's market expand as an energy saving lamp in recent years.We developed Electronic self-ballasted fluorescent lamp with E17 base.E17 base is used kripton lamp and so on.Lighting Equipment for lamp with E17 base is smaller than E26 base.So we studied to design more compact Electronic self-ballasted fluorescent lamp with E17 base.First,We developed 9.8mm 3U-shaped bulb with 35mm height.Second,We developed C-COMP Circuit with compact parts and appropriate position.
As a result,we released glass globe type(Height:99mm,Diameter:55mm) and glass globe less type(Height:90mm,Diameter:44mm).

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We have investigated the failure mechanism of the electrolytic capacitors used in high output self-ballasted compact fluorescent lamps equivalent to 100W incandescent lamps. PBT resin used for the lamp assembly materials has flame retardant which comprise a bromine compound. The failure of the electrolytic capacitor is caused by the corrosion of aluminum electrode; this corrosion is caused by the contamination of bromine compounds in electrolytic solution. The bromine compounds are the decomposition of the flame retardant agent of PBT resin produced in process of the degradation by heat and ultraviolet ray irradiation. We have determined the types of bromine compounds, and also measured the minimum temperature for generating these compounds and the time to failure.

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Large-Area LCDs,40 to 50 inches class,have been developed recently.We have developed 1200 mm length CCFL (cold cathode fluorescent lamps ).This lamp is suitable for 52 inches LCDs for horizontal lamp setting.The luminance of this CCFL at the applied input current of 6 mA were 18000 cd/m2 .We discuss this lamp characteristics in this paper.

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The electronic ballast of the Two-converter system which combined the converter circuit and the inverter circuit with the input waveform improvement for fulfilling an IEC standard in a lighting field is developed. However, this system had many faults. Then, at this laboratory, from before, the neutral points boost converter which has improved the above-mentioned problem was developed, and it applied to the electronic ballast, and has contributed to the lighting field. However, although the above-mentioned converter was a boost type, it had the problem of a reason. Then, this report newly develops a neutral point type down converter circuit, and improves a problem.

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Now, regulation looser than the IEC standard class C which is the usual standard is imposed on the electric bulb form small fluorescent lamp. Therefore, an input waveform is a capacitor input type fundamentally, and is that the measure which extends conduction angle is only taken. However, even if small, it is thought that there is no change in being lighting and it should be satisfied with an IEC standard unexceptional also about a small fluorescent lamp. Then, this report newly develops neutral point type down inverter, and makes one proposal of the improvement about the above-mentioned point.

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In the conventional electronic ballast for lighting, the Two-converter system of the converter circuit part which performs voltage increase or decrease, and the inverter part to switch was proposed. However, part mark increase by this method. Therefore, problems such as a miniaturization and cost, cannot be denied. Then, at our laboratory, the neutral point type inverter was devised and it has contributed to improvement of an electronic ballast. The neutral point type down converter is proposed this time. This system is the same electronic ballast of one converter which increase voltage, and became the electronic ballast which satisfied the IEC standard class C.

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Y₂O₃:Eu³⁺ is mainly used for red phosphors of fluorescent lamps. However, it has the problem that the color purity is not good and the decay time of the emission is long. On the other hand, new red phosphors with efficient luminescence by UV-LED excitation are also required.Therefore, We researched Eu-doped oxide phosphors in lithium borate systems for fluorescent lamps and LEDs. The result of luminescence properties, it is found that the emissions is deeper red and shorter decay profile than Y₂O₃:Eu³⁺. Moreover, it seems that the emissions is effectively stimulated by UV-LED.

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The radiation mechanism of cluster lamps is based on an idea to create and to heat small particles (clusters) in a high-pressure discharge and to use the thermal emission spectrum of these clusters for light generation. B.Weber and R.Scholl say that clusters emit incandescent radiation corresponding to their temperature, which is the local plasma temperature where clusters take place, 3800K for tungsten cluster or 4600K for rhenium cluster. So it expects that rhenium clusters emit higher luminous efficiency than tungsten clusters. We compare optical properties of rhenium clusters radiation with tungsten clusters radiation. This presentation releases the result of it.

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In this research, the radiative characteristics of noble of mercury-less lamp, which has a pair of internal and external electrodes, were measured. I measured the voltage, the current, the input power and the luminance, when the negative polarity voltage pulse was applied to these types of lamps the frequency of 10 to 60 kHz. Both the luminous and the efficacy of the lamp with an internal electrode was larger than that of the lamp without an internal electrode. This result is due to the wider area though which more emission luminous flux come out without protection by external electrode. From now on, the optimisation of the conditions such as the voltage waveform, the filling gas and pressure is necessary for higher efficacy.

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For various reasons,compact fluoresecent lamps are mainly operated that the electrodes driven by an electronic ballast will be exposed to serious ion bombardments during ignition process and the electrodemay be broken ebenif emitter still remains.It is also reported that the glass envelop of the lamp accidentally melts down at the end-of-life due to the discharge formed at the broken electrode.In this study,erosion phenomena of the tungsten-coil electrode during ignition phase are investigated.When ignition voltage is applied across the emitter-less electrode,discharge current tends to concentrate at the connecting point of tungsten coil andthe supporting pole.Then ,the electrode erosion by ion bombardments will occur at this point due to the high accelerating voltage and current concentration.The reason why discharge current concentrates such portion might be due to the formation of high electric field produced by geometry effect.

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In recent years, the CCFL has been used for Liquid Crystal Backlight in Display. From an environmental recycle point of view, the Dielectric Barrier Discharge (DBD) Lamp has attracted special interest in place of the CCFL, the electric equivalent circuit of this lamp is represented by the diode bridge, voltage source, two capacitor capacitances. The measuring method to determine these circuit parameters is described. The low cost high-efficiency voltage resonance high-frequency inverter with a high frequency transformer which is composed of MOSFETs is introduced in order to drive DBD lamp. The dimming control scheme is based on the pulse density modulation technique.

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The purpose of this study is to remove the nitrogen oxide from the surface of the material. The nitrogen oxide is one of important problems in the air pollution. The nitrogen oxide is removed by using the oxidation action of the material. The optical catalyst material has the oxidation action on the surface of the material. Titanium is of great use for the optical catalyst material. The functionally graded materials(FGMS) have been developed in Japan. In this paper, these constituents of materials are distributed in continuous gradation in order to design using a combination of titanium oxide and Korean kaolin.

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For development of compact ceramic metal halide lamps with EZ14 base, design for new EZ14 base was done for HID ballast system.

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High frequency operation of HID lamps has an advantage for minimization of their electric control gears. However, the operation has a risk of the acoustic resonance phenomena, which would cause some critical problems, such as extinguish problem. In this study, the relationship between stability of plasma and operating frequency as a parameter of arc tube size was investigated using compact ceramic metal halide lamps having very precise dimensions. As a result, it is clear that an appropriate frequency band for stable operation is existed in range of 40kHz to 50kHz.

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New 700W Metal Halide Lamp adapted Mercury Ballast has been developed. New one makes lamp efficacy increased by 10% compared with conventional one. Concerning life span, it extends for 3,000 hours. Higher wall loading is capable of lamp efficacy increasing. This results in high vapor pressure of halide, which causes thinner arc. Adding to this, lamp current is high compared with low wattage: 100-400W. These matters occur unstable arc like snaking and bending. Unstable arc has temperature of quartz wall increased. And lumen maintenance is low. Because high temperature is easy to generate Sc2Si2O7 and ScSi, quartz tube is whitening. On this new lamp, CsI is filled additionally as measure against unstable arc. Some tests show filling CsI by 8.0mol% is effective in improving lumen maintenance.

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The Photodynamic Therapy(PDT) is to concentrate a sensitizer onto tumor cells, produce active oxygen by irradiation of particular wavelength light, and make the tumor cells perish. Recently PDT is studied much, and partly realized. The halogen lamp and Xenon lamp are usually used as light sources for study and experiment. on the other hand, some devices in the hospitals use laser light of die laser excited by another laser. The authors develop a new metal halide lamp for PDT which has more than double the efficacy of halogen lamp or xenon lamp at 635+-15nm and 670+-15nm for 5ALA. The new metal halide lamp has 4mm arc length, and is suitable for fiber device and also diffusing projection device for, particularly the therapy of human skin.

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Un-inputting.

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It was examined about the one for dimmable electronics baiiast.Dimmer signal is PWM form.It has dimmable lighting by controlling lamp electric power.The characteristics of the product.(1)100_-_25% continuance dimmer.(2)Division of an errand of the lampe can be done.

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A new converter circuit topology has been proposed to miniaturize the electronic ballast for low wattage HID lamp. The feature of this topology is to form a closed loop consisting of at least power supply and the primary winding of the converting transformer even off duration of the converting switch. By utilizing the proposed circuit, the peak current in primary winding can be decreased. Therefore the size of transformer can be reduced. In our experiment 35W-HID ballast was designed using the proposed topology. The result shows more than 10% reduction in the peak current compared with the conventional flyback converter.

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Recent rising demands for energy saving and environmental conservation encourage the developments of high efficiency and long life light sources. Application of electrodeless discharge technique is one of the most important solutions for that. In this study we show the development of new electrodeless compact fluorescent lamp available for home use. We developed the low frequency (480kHz) driving technique of inductively coupled discharge so that we can use ordinary circuit components. To maintain the steady discharge plasma with such a low frequency, the buffer rare gas composition and its charge pressure were optimized. As a result, we realized a new electrodeless compact fluorescent lamp with extremely long life (30000hours) and high efficacy (68lumen par Watt).

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We studied electrodeless fluorescent lamp ballast that is drived in low-frequency around several hundred kHz. We found that the frequency band for stable lamp operation gets narrower as the driving frequency becomes lower. That was caused by higher Q-factor of induction coil.
We studied a new frequency control method in order to adjust the ballast operating frequency into the frequency band for stable discharge. In that, the current of a semiconductor switch in the inverter is monitored, and it is controled to be zero at the moment of turning off. As the result, the electrodeless lamp is operated successfully because of this frequency control.

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The electrodeless discharge has an advantage that the corrosive material can be used since there is no reaction with electrode material. The molecules are attractive as filling material of lamps by their radiation from vibrational and rotational levels. High efficacy and CRI can be expected. We selected MgD as filling material as the candidate for high efficacy. The arc tube is composed of sapphire and PCA. Mg, Ar and deuterium are filled into arc tube. We confirmed the MgD radiation that has the characterized P-head position that was matched to calculated position. The efficiency of MgD is 27% higher that that of MgH. The measured efficiency is 14.6%. We guess that is due to the reduced elastic collision loss.

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Microwave cavity operated with frequency under cut-off frequency can emit light efficiently without microwave leakage. Power absorption efficiency is examined using dummy carbon load. The results are as follows. (1)Maximum power absorption is obtained when the antenna length is a fourth or three fourth of wavelength. (2)Under condition that the loads are contacted with antenna, power absorption of circle plate load is higher than that of a sphere load. (3)The absorption efficiency is the highest when the load diameter is the biggest at the position of the antenna tip. (4)The power absorption efficiency of a low resisitant load is higher than that of a high resistant load.

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Nothing

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The conditional expression for high efficiency to operate with MHz was found for FET on inverter for the electrode-less discharge lamp. Then, the validity of that ceremony which guided it experimentally was confirmed.

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Excimer lamp is short life. Therefore, it is necessary to improve this performance. This time, we developed long life excimer uv irradiation unit with control function of lamp current.

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Excimer lamp is difficult to ignite and maintain a light for high frequency and high voltage. We developed reliability electric ballast circuit.

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Deveropment of Table Light with Negative air ions

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Recently, there has been an increasing need for lighting control systems with illuminance sensors or motion sensors to save energy. To realize easy installation of them, we have developed lighting units that communicate each other with infrared rays network.
Each unit has a dimming electronic ballast and an IR communication part. A unit with an illuminance sensor and a motion sensor sends control signals to no-sensor units.
Each unit dims itself according to the signal, at the same time, it transfars the same signal to other units, and all the units in a system will be controled simultenuously.

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In New Hi-Efficiency Indirect Lighting, New Luminaire(consist of Aluminium Reflector and Aluminium Louvers) was developed. New Luminaire's Efficiency was 93.7%. New Luninaire were attached on Top Wall, and Room Ceiling was lighted up New Luminaire.[Results] Under New Indirect Ligthing condition, compared with Direct Lighting(*1),1.Glare and Veiling Reflection phenomena never occurred.2.In Narrow space room(4 by 4m, ceiling height: 2.7 m), Horizontal Luminance(average) was 94.1%(measured value). 3.In Wide space room(more than 14 by 15.75m, ceiling height:2.7 m), Numbers of Luminaire were reduced to 86.8-90.6%(calculated value).[*1 Luminaire: Reflector and Louvers were coated with White Melamine ]

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Development of floodlight under consideration of environmental protection

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Toyota junction is located in Toyota city, Aichi prefecture. It connects the present National Moterway,first Tokai Line and National Moterway,Second Tokai Line constructed with the three layers. The designed speed limit is from 60km/h to 80km/h and its total area is 200.000 square meters.The special features on the latest line lightning at low position installed on this junction are the following;
1 The Pro beam distribution of luminosu intensity by the optical panel has improved the drivers' capacity in recognizing the car ahead.
2 This system emits the light with the more included angle, compared to the former one, which has improved the efficiency. This also controls the escape of the light.
This line lighting installation at low position ensures the drivers' safety and effect of visual guidance, as well as considering the surrounding environment and scenery.

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The purpose of this research is carrying out the design of the light which excelled for building the comfortable space in lighting environment, such as office and a school, i.e., designing of luminaire reflector which can control of light intensity distribution which suppressed such reflection it is thought that is unpleasant, and also suppressing luminance increment on tube surface.

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The evolutional methods such as the genetic algorithm and the genetic programming are utilized for the various fields. Recently, as the improvement of them, the artificial life type discovery system has been proposed. In this study, the system is applied to the optical lens design. When some conditions and the target of light distribution are given into the system, the lens shape changes dynamically for satisfying the target of light distribution. For example, when the thickness of the condensing lens is limited to 2mm or less, the lens such as Fresnel lens is automatically discovered by this system.

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In a projection system, the shape of a figure on the screen greatly depends on the position of the projector. If the projector is not set up at the correct position, the projected figure is distorted. Therefore, when the projector is not set up at the correct position, it is necessary to correct the shape of the figure. Thus a method for correcting the distorted figure is proposed. This method uses an artificial life type function discovery system. A conversion function, which shows the relationship between the figure on the display of the computer and that of the projected screen, is automatically calculated by the use of S-System. As the result, the shape of the figure on the screen can be displayed without distortion, regardless of the projector-position and the direction.

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It is important to consider the characteristics of the shadow caused on the working plane in lighting design.
Then, the algorithm about approximate prediction of the characteristics of the shadow on the working plane is examined under Task Ambient Lighting which is one of the office lighting systems.
As a result, if the algorithm of prediction which is considered a geometrical relationship among the light source, the shadow caster and the receiving plane is used, the maximum of the shadow factor and the area of the shadow, which is the characteristics of the shadow, will be able to predict approximately from little amount of information.

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The objective of this research work is to propose a practical method of evaluating discomfort glare from windows. It is an issue in evaluating discomfort glare from windows that the glare source is rather large compared with luminaires. In this report (Part 1), variations in Glare Constant are investigated for the position of the glare source in the visual field. Luminance that caused a standard sense of glare was measured using a self-made glare meter. The result shows that Glare Constant changes with the position of the glare source.

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The objective of this research work is to propose a practical method of evaluating discomfort glare from windows. The conventional method has an issue that the Position Index is not defined for the whole visual field. Following the previous report (Part 1), a new Glare Constant formula is proposed in this report. From measurements, luminance that causes a standard sense of glare was investigated for each of the size and the position of the glare source and the background luminance. The proposed Glare Constant formula takes the position of the glare source into account, and does not require the Position Index.

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The purpose of this research is to examine the actual conditions of daylight and solar radiation and to analyze the relationship of these to clouds. Global horizontal illuminance and irradiance increase with increasing solar altitude, and decrease with increasing cloud amount except in the case of high clouds. High clouds have no substantial influence on changes of global horizontal illuminance and irradiance. Diffuse horizontal illuminance and irradiance increase with increasing solar altitude, and increase with increasing cloud amount. Global horizontal illuminance/irradiance ratio increases slightly with increasing cloud amount. Diffuse horizontal illuminance/irradiance ratio decreases with increasing cloud amount.

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In addition to the research in last year,we researched obstacles dropped inthe Toumei and Tohoku motorway in the same way as we did in last year.We foundout that revealing power of 20% reflection obstacles was about 65% as a result of this research.This revealing power curve is based on the reserch,which is held in several places and seasons,so that it can be a very useful basic data of road lighting design.

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Total revealing power is one of the criterion of visibility of road lighting,and it defines the sum of therevealing power of silhouette vision and reverse silhouette one. We found out that revealing power of obstacles which has 20% reflection dropped on the motoway is 65% by the research in 2002- 2003,and there are comparatively muchhigher reflection than Smith's study.As a result,it is important to keep road surface luminance to satisfy the required visibility,and vertical illuminance can be either higher or lower,depending on the purpose something like making preceding cars more clearly.

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Uniformity of the road surface luminance must be kept up satisfactority in term of influence on visibility of the obstacles on the road and comfortable.We experimented about the effects of longitudinal uniformity on discomfort level of driver using computer graphics devices,after that studies permissible value of longitudinal uniformity for tunnel lighting.Results of experiment showed permissible value of longitudinal uniformity depended on space of the luminaires,but not on driving speed and averege of the road sueface luminance,and permissible value of longitudinal unformity for tunnel lighting ranged between 0.91 and 0.78 for from 5m to 20m on space of luminair

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In the composition of pleasant visual environment, modeling is a critical factor. When the modeling of person's face is examined, the clay figure and the mannequin, etc. are used well. Recently, the technology of computer graphics (CG) develops rapidly. Came to being able to draw person's face etc. freely, and setting the condition of the light irradiation carefully became possible. Then, the CG image of the face of the person who illuminated it under various conditions was made by using this technology, and the modeling effect by seeing Can evaluation was examined.

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This Paper describes a new method ofcalculating illminance from an elliptical surface light source by applying Legendre Gauss (L G)numerical integration to a generalized contour integration method.Then,to obtain the illuminance of an illuminated surface positioned off-center from an elliptial light source,we present an illuminance calculation method and illuminance calculation formula using a generalized contour integration method with Legendre Gauss numerical integration.We also show that the proposed method can be useful in calculating illuminance from a surface light source.

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