Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 318
Fig. 3. excess of regular reflection, as shownin Fig. 5, in which most of the rayA goes in the direction E, while /y//////vw//// ; , ^_,^ //. … Fig. 4. that in the required direction, F, isvery feeble. Now% at that rate, itwould need a prohibitive quantity ofinitial light to produce ever a modestillumination on the reading area. Whynot form the ceiling so as to direct the correct curve may be found by workingout a series of tangents each…
Lighting
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