Interior Illumination Research Articles

Interior Illumination Calculation by Average Illumination Method

Average illumination is one of the most important indices in illuminating engineering. The lighting design often includes a prediction of the average illumination on the working plane or on the floor and the illumination and luminance distributions within the room. But, to calculate the value of it theoretically is quite difficult becase of the complexity of the calculatin. conditions. In that case, measuring is only way to obtain the values.For the calculations of average illumination, the authors used average illumination method in which readings taken at specified positions are weighted according to their positions.In this paper, to estimate the errors of the average illumination method and know its practicality and usefulness the following process was taken.1. Obtain average illumination by interreflection method and regard it as standard illumination.2. Obtain illumination distributions at specified positions-by-point by point method and using them get approximate value of average illumination.3. Compare average illumination by interreflection method with the above values for various room conditions.In case of luminous ceiling and panel lighting, the authors confirmed the practicality of average illumination method under various conditions.

An omnidirectional photometer of small dimensions

This omnidirectional photometer is intended for the measurement of daylight under grass swards; but the principle used in the instrument can be applied to measure the mean illumination at a point in other cases, for example, interior illumination. It consists of two small circular barrier layer cells, insulated from one another and mounted back to back, each being surmounted by a translucent diffusing hemispherical shell, diameter 5/8 in. The cell sensitivities are adjusted electrically to equality, the combined output being read on an indicating meter. Even for collimated light the response is uniform with orientation to better than ±5%.

Engineering auditorium lighting improved

THE illumination of the auditorium in the Engineering Societies Building has been for several years the subject of study at the request of United Engineering Trustees, Inc., by Institute members specializing in lighting. Increased daytime use of film and slide projection had been hampered by daylight filtering through roller shades and the interior illumination had been pronounced obsolete, inadequate, and difficult to maintain. In an effort to improve the building facilities for their Founder Societies and associates, the board of trustees of United Engineering Trustees, Inc., undertook the modernization of this meeting hall and authorized the replacement of the false skylights with a more permanent boarding and a thoroughly modern lamp system.

Auxiliaries for High-Voltage D-C. Multiple Unit Cars

The selection and application of auxiliary electrical devices on a high-voltage multiple unit car is of almost as much importance as the application of the main traction apparatus and requires careful consideration. This paper contains a description of the engineering features as worked out for electrified suburban lines operating on 1500-volt and 3000-volt systems. The control circuits have become very generally standardized at 32-volts, which is also well adapted for interior illumination and headlights. A motor driven generator supplies 3-to 5-kw. power per unit for control lights and battery charging. Such devices as heaters and motor-generator sets, requiring a considerable amount of electrical power, are necessarily constructed to operate at trolley potential. On the 1500-volt system, the compressor can be operated directly from the line potential while on the 8000-volt systems, a double commutator motor driving the generator supplies a 1500-volt source of power for the compressor.

Auxiliaries for high-voltage D-C. multiple unit cars

The selection and application of auxiliary electrical devices on a high-voltage multiple unit car is of almost as much importance as the application of the main traction apparatus and requires careful consideration. This paper contains a description of the engineering features as worked out for electrified suburban lines operating on 1500-volt and 3000-volt systems. The control circuits have become very generally standardized at 32-volts, which is also well adapted for interior illumination and headlights. A motor driven generator supplies 3-to 5-kw. power per unit for control lights and battery charging. Such devices as heaters and motor-generator sets, requiring a considerable amount of electrical power, are necessarily constructed to operate at trolley potential. On the 1500-volt system, the compressor can be operated directly from the line potential while on the 8000-volt systems, a double commutator motor driving the generator supplies a 1500-volt source of power for the compressor.

The Graphical Method of Design of Interior Illumination

本丈は屋内照明の設計及び計算を簡便に行ひ得る圖式計算方法を示したものである.

On “The Graphical Method of Design of Interior Illumination” by Prof. Kadokura

On “The Graphical Method of Design of Interior Illumination” by Prof. Kadokura

Reflection Characteristics of Projection Screens

When it is considered that the enjoyment of the entertainment offered in the motion picture theater depends almost entirely upon the visual organs, it will be recognized that the importance of providing conditions which will result in the least possible visual fatigue to the audience cannot be overestimated. There are many factors which deserve the consideration of the motion picture engineer in order that the maximum of visual comfort may be obtained, among which may be mentioned the proper distribution of the interior illumination, the elimination of excessively bright surfaces in the field of vision, and the proper adjustment of the screen brightness. The fact that the attention of the audience must remain fixed for long periods of time upon the projected picture makes it of utmost importance that the projecting system be so adjusted that the screen brightness is neither so high as to cause visual fatigue due to glare, nor so low as to throw an undue burden upon the retinal accommodation.

The Interior Illumination of the Motion-Picture Theatre

The desirability of providing sufficient illumination for the convenience and comfort of the audience, if this can be accomplished without perceptible loss of quality in the projected picture, is obvious. It is scarcely necessary to enumerate the many serious objections to the use of very dimly lighted rooms in which motion pictures are being exhibited to large audiences. The difficulty encountered by persons entering from the relatively brightly lighted exterior regions in finding their way to unoccupied seats is considerable, The undue strain thrown upon the accommodation processes of the retina resulting from a sudden transition from a brightly lighted exterior to a dark interior, or vice versa, is very objectionable and to be avoided if possible. More serious than these, however, is the excessive visual fatigue and eye-strain resulting from a prolonged observation of a brightly illuminated area (such as the screen on which the picture is being projected) occupying but a small portion of the field of view and surrounded by very dark areas, this condition being ideal for the production of glare effects due to excessive contrasts. It is evident for the satisfactory exhibition of motion pictures that the general illumination in the theater must be subdued in order that the projected picture shall be of good quality as regards its apparent brightness and contrast, and that in raising the value of the general room illumination there is a limit beyond which it is impossible to go without seriously affecting these characteristics of the picture. However, it has been found by proper distribution of the light that the general room illumination can lie raised to a value sufficient to eliminate all of the objections to a dimly lighted theatre and at the same time produce no perceptible injurious effect upon the quality of the projected picture.

Discussion on “industrial illumination and the average performance of lighting systems” (Clewell), and “the problems of interior illumination” (Jones), Boston, Mass., June 26, 1912. (see proceedings for July and June, 1912)

Discussion on “industrial illumination and the average performance of lighting systems” (Clewell), and “the problems of interior illumination” (Jones), Boston, Mass., June 26, 1912. (see proceedings for July and June, 1912)

The Problems of Interior Illumination

The practise of illuminating engineering as a separate profession is a recent development of applied science. So short a time ago as 15 years there was little if any room or need for such work, and the “art of illumination” was largely a matter of guess work, precedent, and simple attempts to produce artificial light with little attention given to its distribution from the standpoint of economy as that word is understood today.

The problems of interior illumination

The practise of illuminating engineering as a separate profession is a recent development of applied science. So short a time ago as 15 years there was little if any room or need for such work, and the “art of illumination” was largely a matter of guess work, precedent, and simple attempts to produce artificial light with little attention given to its distribution from the standpoint of economy as that word is understood today.

Discussion on ``Industrial Illumination and the Average Performance of Lighting Systems'' (Clewell), and ``The Problems of Interior Illumination'' (Jones), Boston, Mass., June 26, 1912

Discussion on ``Industrial Illumination and the Average Performance of Lighting Systems'' (Clewell), and ``The Problems of Interior Illumination'' (Jones), Boston, Mass., June 26, 1912

Prismatic lighting for the illumination of dark interiors

Prismatic lighting for the illumination of dark interiors