Illuminated sign and method for design

摘要

An illuminated sign designed to be viewed from a horizontal line of sight of an observer, the sign comprising: a frame, a partially transparent face thereon, tubing mounted therein and having an inside radius (r), and a single or plurality of concavely-curved, reflective channels each being substantially semi-cylindrical and having a radius (R), and positioned at a distance (d) from the luminous tubing; wherein the improvement comprises each channel having an angle of wrap (beta) approximately equal to about 70% to about 150% of the value that solves the equation 1 $\frac{1}{\sin \left(\frac{\mathrm{beta}}{2}\right)}+2\left(\frac{R}{r}-\frac{d}{r}-1\right)\cos \left(\frac{\mathrm{beta}}{2}\right)=\frac{R}{r}.$ The method of designing such a sign comprises selecting the illuminated tubing with inside radius (r), determining the distance (d) between the tubing and the reflective channel, selecting the substantially semi-cylindrical reflective channel radius (R) and designing the angle of wrap (beta) as defined above.