Illuminated sign and method for design

• US 20010045034A1
• Filed: 07/13/2001
• Published: 11/29/2001
• Est. Priority Date: 12/04/1997
• Status: Active Grant

• Current Assignee: The Change-A-Brill Company, LLC
• Original Assignee: Lance Mueller
• Inventors: Mueller, Lance, Gleeson, Patrick F.
• Granted Patent: US 6,607,412 B2
• Time in Patent Office: Days
• US Class Current: 40/564
• CPC Class Codes: F21V 7/005 with an elongated shape to cooperate with linear light sources
• CPC Class Codes: F21V 7/04 Optical design
• CPC Class Codes: F21V 7/24 characterised by the material
• CPC Class Codes: F21V 7/28 characterised by coatings
• CPC Class Codes: F21Y 2103/00 Elongate light sources, e.g. fluorescent tubes
• CPC Class Codes: G09F 13/04 Signs, boards or panels, illuminated from behind the insignia
• CPC Class Codes: G09F 13/0422 Reflectors
• CPC Class Codes: G09F 13/0472 Traffic signs
• CPC Class Codes: G09F 13/0481 Signs, boards or panels having a curved shape
• CPC Class Codes: G09F 13/14 Arrangements of reflectors therein
• CPC Class Codes: G09F 2013/145 curved reflectors
• CPC Class Codes: Y10S 362/812 Signs

Abstract

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 (β) approximately equal to about 70% to about 150% of the value that solves the equation $\frac{1}{\sin \left(\frac{\beta }{2}\right)}+2\left(\frac{R}{r}-\frac{d}{r}-1\right)\cos \left(\frac{\beta }{2}\right)=\frac{R}{r}.$

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 (β) as defined above.

Claims

1. An illuminated sign designed to be viewed from a horizontal line of sight of an observer, the light box comprising:

a frame having a width;

a partially transparent face supported thereon;

a single or plurality of lengthwise sections of luminous tubing mounted in the frame and having a tubing inside radius (r) and an inner surface having a reflector-closest edge, and;

a single or plurality of concavely-curved, reflective channels each having an angle of wrap (β

) and a concave surface having a tubing-closest edge positioned at a distance (d) from the tubing inner surface reflector-closest edge;

a reflective channel having a substantially semi-cylindrical shape with a radius of curvature (R)

wherein the improvement comprises each said reflective channel having an actual angle of wrap (β

a) approximately equal to about 70% to about 150% of a calculated value for β

c which solves an equation consisting of;

$\frac{1}{\sin <br><br>\left(\frac{\mathrm{\beta <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>c}{2}\right)}+2<br><br>\left(\frac{R}{r}-\frac{d}{r}-1\right)<br><br>\cos <br><br>\left(\frac{\mathrm{\beta <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>c}{2}\right)=\frac{R}{r}.$

2. The illuminated sign of

claim 1

wherein the actual angle of wrap (β

a) is approximately equal to about 80% to about 140% of the value β

c.

3. The illuminated sign of

claim 1

wherein the actual angle of wrap (β

a) is approximately equal to about 90% to about 130% of the value β

c.

4. The illuminated sign of

claim 1

wherein the plurality of lengthwise sections of luminous tubing comprise a plurality of parallel neon or fluorescent tubes.

5. The illuminated sign of

claim 1

wherein the light box is further designed to be viewed at a maximum viewing angle (α

) from a horizontal line of sight of an observer and the radius of curvature (R) is approximately equal to about 80% to about 120% of r×

(1+1/(sin α

))+d.

6. The illuminated sign of

claim 1

wherein the frame comprises a material selected from a group consisting of:

aluminum, a non-aluminum metal, and plastic.

7. The illuminated sign of

claim 1

further comprising a diffusion plate mounted to the frame or to the partially transparent face.

10. The method of

claim 3

comprising selecting values for the luminous tubing inside radius (r), the distance (d), the reflective channel radius (R) and angle of wrap (β

) that minimize visible streaks of brighter and less-bright illuminated regions in the sign.

8. A method for designing an illuminated sign having a plurality of lengthwise sections of light-emitting luminous tubing and a plurality of concavely-curved reflective channels having a substantially semi-cylindrical shape with a radius of curvature (R), each channel positioned to reflect a portion of the light emitted by one of said lengthwise sections, the method comprising the steps of:

(a) selecting the luminous tubing, said tubing having an inside radius (r) and an inner surface having a reflector-closest edge;

(b) selecting a distance (d) between the tubing inner surface reflector-closest edge and a tubing-closest edge of the reflective channel adjacent thereto;

(c) forming the reflective channels to be substantially semi-cylindrical in shape with actual angle of wrap (β

a) approximately equal to about 70% to about 150% of a value for β

c which solves an equation consisting of;

$\frac{1}{\sin <br><br>\left(\frac{\mathrm{\beta <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>c}{2}\right)}+2<br><br>\left(\frac{R}{r}-\frac{d}{r}-1\right)<br><br>\cos <br><br>\left(\frac{\mathrm{\beta <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>c}{2}\right)=\frac{R}{r}.$

9. The method of

claim 8

further comprising determining a maximum viewing angle (α

) from which an observer will view the sign, measured from a horizontal line of sight, and in step (c), forming the channels to have a radius (R) approximately equal to about 80% to about 120% of r×

(1+1/(sin α

))+d.