Journal of Light & Visual Environment
Online ISSN : 1349-8398
Print ISSN : 0387-8805
ISSN-L : 0387-8805
Volume 1, Issue 1
Displaying 1-12 of 12 articles from this issue
  • Taisuke HIROTA, Hiroshi OHNO, Hiroshi WATANABE, Hiroshi MORITO
    1977 Volume 1 Issue 1 Pages 1_1-1_6
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    Mercury dosing in fluorescent lamp is essential because fluorescent lamp exploit the ultraviolet radiation emitted by mercury atoms. As regards mercury dosing into the bulb, the method which drops a few drops of liquid mercury through the exhaust tube has been employed. Such conventional method in production is of advantage to exhaust the gaseous impurities from the bulb but brings about various defects quality and characteristic. To eliminate such disadvantages, a manufacturing method which uses a mercury dispenser such as a strip mounted around the electrode and releases mercury within the tube by means of R. F heating after sealing is introduced. Advantages using mercury dispenser are as follows; (1) the quantity of mercury enclosed in the lamp is very precise, (2) the pressure fluctuation of argon fill can be reduced, therefore it is possible to prevent the fluctuation of lamp life and to increase its average life. (3) lumen maintenance can be improved because less mercury condensation on the phosphor coating and getter action of mercury dispenser. As a conseguence, the total amount of light output during life is increased and the total lamp efficiency is also improved.
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  • Ikuo IWAI, Masafumi OCHI, Motonobu MASUI
    1977 Volume 1 Issue 1 Pages 1_7-1_12
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    In experiments on high pressure sodium lamps, we found that lamp efficacy is increased about 10% and that lamp extinction characteristics improve remarkably when the filling pressure of inert gas xenon is increased from the conventional 20 torr up to 350 torr. The improved efficacy is thought to be due to the reduction in thermal conduction loss caused by the lowered thermal conductivity of the discharge gas. The improved extinction characteristics are caused by the considerable lowering of lamp reignition peak voltage due to the same reason. Utilizing these effects, we designed a new type of high pressure sodium lamp to increase lamp efficacy while still using ordinary high pressure mercury lamp ballast. The new lamp uses the ballast of 400 W mercury lamps, requires 360 W of input, and has 138 lm/W of lamp efficacy. For the starting device, we designed an improved bimetal switch that is built in the lamp bulb.
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  • Keiji WATANABE, Masato SAITO, Michihiro TSUCHIHASHI
    1977 Volume 1 Issue 1 Pages 1_13-1_17
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    Emission and evaporation characteristics of Ba1.8 Sr0.2 CaWO6 coated emitters are affected by the addition of aluminum oxide and yttrium oxide. An emitter consisting of a mixture of Ba1.8 Sr0.2 CaWO6 and 11.5% (wt.) aluminum oxide has a higher emission current and a higher evaporation rate of active barium than does an emitter of the tungstate alone. X-ray diffraction analysis of the surface film of the emitter clearly indicates that this high evaporation rate is due to the presence of BaAl2O4 produced by the reaction of the tungstate with aluminum oxide. Yttrium oxide does not react with the tungstate. An emitter consisting of a mixture of Ba1.8 Sr0.2 CaWO6 and 21.9% (wt.) yttrium oxide has a lower emission current and a lower barium evaporation rate than does an emitter of the tungstate alone, presumably because the rate of barium formation in the emitter decreases with the addition of yttrium oxide. When these mixtures are applied to the electrodes of 400-watt high-pressure mercury lamps, the light output maintenance of the lamps using the latter mixture is superior to those using the former mixture. This is related to the evaporation rates of the mixtures.
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  • Kazuyoshi MASUMI, Hiroshi Bo
    1977 Volume 1 Issue 1 Pages 1_18-1_23
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    The operating circuits for discharge lamps with various lamp voltages which differ from usual ones are analyzed by the simulation method. The coefficients of the mathematical model equation shown in the previous paper for different lamp voltages are determined by the assumption that the operating waveforms of the voltage and current of different voltage lamps are similar to those of commercially available lamps. In the case of various lamp voltages at rated power (400 W) operation, operating circuits of a reactor type and a reactor-capacitor type for the mercury discharge lamps are analyzed on a digital computer. For both of these types, operational characteristics at various ratios of lamp voltage to source voltage are obtained by this analysis. Optimization of operating circuits is discussed from various points of view, such as the circuit power factor, the lamp current fluctuation rate, the current wave peak factor, the capacitor voltage and the physical size.
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  • Akihiro INOUYE, Yoshiaki TERASHITA, Kazuyuki OGAWA
    1977 Volume 1 Issue 1 Pages 1_24-1_28
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    A theory for statistical distribution in discharge lamp breakdown voltage has been developed. It is shown that the decreasing constant of the breakdown voltage distribution under linearly increasing voltage is almost proportional to the product of the breakdown probability P due to one initial electron and the number of initial electrons Q liberated from a cathode per second. When AC voltage is applied to a lamp, starting time lag τ is equal to ‹PQ-1, where ‹PQ› is averaged PQ over one applied voltage perid. τ is also expressed as the inverse value of breakdown probability T1 per one applied voltage period and its frequency F. This expression is practicable because T1 is directly measurable. Discharge lamps were examined by the statistical method and it was concluded that T1 is a better papameter than breakdown potential V8 for judging lamp and starting device qualities.
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  • Isao KANEDA
    1977 Volume 1 Issue 1 Pages 1_29-1_39
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    This paper relates to a novel discharge lamp operating system proposed for energy optimization and saving of resources, which employs a powerful oscillator to supply reignition energy immediately after lamp current pause of each half cycle of a.c. source in order to realize sub-stantially the same source and lamp voltages. Features of the system are investigated by analogue computer simulation on the trial for single 4OWT12 fluorescent lamp operating circuit at 100V line comparing with that of conventional single winding choke at 200V line. The following are improvements expressed by approximate estimates.
    (1) Inductance value and the maximum energy stored in a ballast are decreased to one fifth and one fourth, respectively.
    (2) Ballast weight and loss become one fourth and one third, and these ratios for a conventional rapid-start ballast will become one eleventh and one fourth, respectively.
    (3) Total efficacy becomes 116 percent, and for the rapid-start ballast it will become 131 percent. Further, this will be much raised by the use of a particularly designed lamp.
    (4) Power factor becomes 89 percent in lag phase.
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  • Takashi HIGO, Norio MUROI
    1977 Volume 1 Issue 1 Pages 1_40-1_49
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    It is the objective of this paper to discuss the photometric capabilities of silicon photovoltaic cells operated in “short circuit mode” at low-level-light. In order to predict the performance of photometric circuits of silicon cells are evaluated by applying the damped least-square method to the voltage-to-current diode characteristic of silicon cells. The linear response of silicon cells combined with a DC amplifier circuit is considered, using the cell parameters. This indicates that a low noise DC amplifier in the nanovolt region is suitable for the measurement of low-level-light. As an example of a low noise DC amplifier, a galvanometer amplifier is manufactured for trial. It is shown that the silicon cell combined with the galvanometer amplifier circuit has sufficient sensitivity in comparison with the type of multi-alkali photocell (detectable minimum flux 4.2×10-6lm) to detect the luminous flux as small as 1.6×10-9lm. As an application of this silicon cell combined with a galvanometer circuit, a standard observer is manufactured by using a group of cells plus filters. It is suggested that the spectral sensitivity of the observer approximately matches the CIE spectral luminous efficiency function V(λ).
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  • Koichi IKEDA
    1977 Volume 1 Issue 1 Pages 1_50-1_58
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    The purpose of this study is to clarify quantitatively the relation of the physical nature of figures to the recognition and discrimination characteristics of vision when an observer views and perceives the form of two-dimensional figures. Thus, visual experiments are made by means of standard and test random figures composed of 12×12 square cells, some of which are painted black as picture elements. These figures are recognized and discriminated by several student observers with visual acuity not less than 0.8. Results obtained are as follows:
    (1) Display time duration of 4 to 5 seconds is adequate for observers to recognize or discriminate the stimulus figures.
    (2) Averaged number of additional or subtractive picture elements of test figures required to obtain a constant discrimination rate is proportional to the predetermined number of picture elements of the standard figure; i.e., the Weber ratio is constant.
    (3) Test figures with picture elements of different spatial distributions are discriminated with different discrimination rates, even though the numbers of these elements are the same; i.e., the perceived psychological quantities of picture elements vary with their spatial positions.
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  • Masao INUI, Toshimoto MIYATA
    1977 Volume 1 Issue 1 Pages 1_59-1_63
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    The effect of the visual environment on the subjective assessments of spaciousness, satisfaction and friendliness, and on the preference of activities has been studied. 25 different model conditions were produced by changing each of 5 variables; sky luminance, interior illuminance, window size, method of illumination, and type of furniture. 20 subjects were asked to give their responses to all the conditions. It has been found that those variables related to spaciousness are the sky luminance, interior illuminance and window size, while friendliness has the strongest correlation to the method of illumination and the type of furniture. It can be said that satisfaction has a close relationship with spaciousness whereas friendliness has not. As to activities, a low level of spaciousness suits meditating and contemplating, while a high level suits lecturing and having a meeting. Those activities like resting and having a party, meditating and contemplating, and playing patience have a high level of friendliness.
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  • Toru NOGUCHI, Yoshimichi EJIMA, Hisashi NAGAI, Toko NAKANO
    1977 Volume 1 Issue 1 Pages 1_64-1_69
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    Psychological structure of modelling effect was investigated by the semantic differential method. Under various lighting conditions, the appearance of the objects were appraised with twenty-eight bi-polar adjective scales, and it was found that the structure of modelling was constituted by three factors, which are attractiveness, activity and evaluation. Next, on the basis of three extracted factors, four new scales were constructed for assessment. They were attractive-unattractive, active-passive, harmonious-dissonant and agreeable-disagreeable. Using these scales, modelling effects of four kinds of dresses were assessed under various lighting directions, and the scales were related to the lighting conditions.
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  • Joji INAGAKI
    1977 Volume 1 Issue 1 Pages 1_70-1_75
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
    For the navigators during coastal navigation at night, signal lights such as the navigational aids and the navigation lights of other ships should have a good visual transmission from the view point of navigation safety. In this paper the relation between the recognition of the signal and background lights is described. The measured results of background lights using a wide-angle luminance meter of 20° visual field show that the city lights of medium and small sized cities at night have generally the average luminance of about 10-3 to 10-1 cd/m2 when viewed through clear atmosphere. In order to study various factors affecting the signal recognition an indoor experiment was conducted using a model set in a fog chamber, however, without generating fog in this study. Furthermore, the effect of peripheral vision is discussed.
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  • Michihiro TSUCHIHASHI, Masato SAITO, Makoto YAMANOSHITA, Osamu MYODO, ...
    1977 Volume 1 Issue 1 Pages 1_76-1_82
    Published: 1977
    Released on J-STAGE: June 07, 2011
    JOURNAL FREE ACCESS
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