Chapter 17 

 LIGHTING AND COLOR 



MILES A. TINKER 



University of Minnesota 



Introduction 

 Lighting 



M The problem of artificial illuraination is of 

 primary importance in all inside living and 

 working environments including the subma- 

 rine. To maintain healthful and efficient 

 functioning of the eyes, it is necessary to pro- 

 vide adequate lighting. Unquestionably, 

 proper illumination contributes much to 

 comfort and efficiency in activities of daily 

 life. Performing visual work under faulty 

 illumination frequently results not onh^ in 

 visual discomfort, but in eyestrain which 

 tends to be accompanied by reflex disturb- 

 ance of other organs of the body. 



In the submarine only artificial illumina- 

 tion is used, and members of the crew have 

 noiTiial vision. Accordingly it is necessary 

 to consider those factors which are basic to 

 artificial illumination adequate for maintain- 

 ing comfortable, healthful and effective func- 

 tioning of normal eyes. These factors are: 

 (1) quality or color of fight; (2) intensity of 

 light in relation to (a) visual acuity, (b) size 

 of object to be discriminated, (c) speed of 

 vision, (d) brightness contrast, (e) efficiency 

 of performance; and (3) distribution of illu- 

 mination and brightnesses within the work- 

 ing environment. The latter includes vari- 

 ous forms of glare and brightness contrast. 

 This distribution of illumination should be 

 so arranged as to give compartments more 

 pleasing appearance and proportions. All 

 three factors should be combined to induce 

 in the inhabitant a sense of tranquillity, com- 

 fort and "hominess." 



The fiterature on illumination is enormous. 

 This report will, therefore, be based upon a 

 sampling of this literature. 



Color 



Certain colors and tints of colors are pre- 

 ferred over other colors and tints. Some 

 colors carry the meaning of warmth, others 

 appear cool. Some are exciting, others sub- 

 duing. To achieve the most pleasing fiving 

 and working environment, these psychologi- 

 cal factors must be considered. 



The role that color in decoration (paint) 

 plays in promoting adequate illumination is 

 important. Much of the usable illumination 

 in an enclosed space should come from reflec- 

 tion of light from the ceiling, walls and fur- 

 nishings. Consequently, attention must be 

 given to the reflection factor of the paint. 

 Also one must consider coordination of illu- 

 mination and decoration. 



Spectral Quality of Color of Light 



In specifying artificial illumination one 

 must decide what light should be used. Sev- 

 eral illuminants, varying in spectral charac- 

 ter, are available: artificial daylight, tung- 

 sten-filament incandescent light, mercury arc 

 light, sodium vapor light, and fluorescent 

 light. 



It is well known that the lens in the human 

 eye has a slightly different focal length for 

 each color of the spectrum. This results in 

 chromatic aberration when the light reflected 

 from an object to the eye is complex, i.e., in- 

 volves several wave lengths. For very near 

 vision, it is possible to focus for violet rays, 

 but somewhat difficult to focus for red rays. 

 In far vision the reverse is true. For inter- 

 mediate distances it is easiest to focus for 

 yellow rays. Thus, when the object is illu- 

 minated by mixed wave-lengths as in ordi- 

 nary lighting, we have chromatic aberration 



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