Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 490
iwwwmninhmmtmmtmtbMwrrmrh 12-30 Projections … sketch, will be mounted a colour screenof six segments, an opaque vane which willcover two segments at the same time, alens and a diffusing plate. The segments of the colour screen willbe of red, green and yellow. The screenwill revolve at the rate of 500 r.p.m. andthe vane at the rate of 499…
Lighting
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