# US 7,172,324 B2 · Internally illuminated light panel with LED modules having light redirecting devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,172,324 B2 - Document ID: US7172324B2 - Status: Granted - Kind: B2 - Application number: 11/028,928 - Filed: 2005-01-03 - Published: 2005-08-11 - Granted: 2007-02-06 - Earliest claimed: 2004-01-05 - Assignees: Leotek Electronics Corporation - Inventors: Chen-Ho Wu; Chinmau James Hwang; Chin-Wang Tu; Ching Yuan Chung - Web page: https://patentgrep.com/patent/US7172324B2 ## CPC - G09F 13/0404: {the light source being enclosed in a box forming the character of the sign} - G02B 6/0021: {for housing at least a part of the light source, e.g. by forming holes or recesses} - G02B 6/0028: {Light guide, e.g. taper} - G09F 13/04: Signs, boards or panels, illuminated from behind the insignia - G02B 6/0018: {Redirecting means on the surface of the light guide} - G02B 6/4214: {the intermediate optical element having redirecting reflective means, e.g. mirrors, prisms for deflecting the radiation from horizontal to down- or upward direction toward a device (G02B6/4246 takes precedence)} - G09F: DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract An illuminated sign having front, back and side surfaces. A plurality of first cavities are formed into the back surface of the sign. A plurality of light emitting modules are disposed in the plurality of first cavities. The modules each include a light emitting diode having an emission axis and for producing at least some light output generally parallel to the emission axis, an optical device disposed adjacent the light source having a reflective surface for reflecting the light output in directions that are generally perpendicular to the emission axis, and a guide element disposed adjacent the optical device for coupling the reflected light output into the interior of the sign. The guide element includes a second cavity formed therein in which the optical device is disposed. The front surface is illuminated by the coupled light output from the light emitting modules by reflection and/or diffusion inside the sign. ## Claims ### Claim 1 A sign, comprising: front, back and side surfaces that define an interior of the sign; a plurality of light emitting modules mounted to the sign, each of the modules including: a light source having an emission axis and for producing at least some light output that is generally parallel to the emission axis, an optical device disposed adjacent the light source having a reflective surface for reflecting the light output in directions that are generally perpendicular to the emission axis, and a guide element disposed adjacent the optical device for coupling the reflected light output into the interior of the sign; wherein the front surface is illuminated by the coupled light output from the light emitting modules. ### Claim 2 (depends on 1) The sign of claim 1, wherein a plurality of cavities are formed into the back surface, and wherein the plurality of light emitting modules are disposed in the plurality of cavities. ### Claim 3 (depends on 2) The sign of claim 2, further comprising: reflective material disposed along surface portions of the cavities. ### Claim 4 (depends on 1) The sign of claim 1, further comprising: reflective material disposed along the back and side surfaces. ### Claim 5 (depends on 1) The sign of claim 1, wherein the front surface includes edge portions that are opaque, and wherein the plurality of light emitting modules are disposed under the opaque portions. ### Claim 6 (depends on 1) The sign of claim 1, wherein the front surface is irregularly shaped. ### Claim 7 (depends on 1) The sign of claim 1, wherein for each of the light modules, the reflective surface is conical in shape. ### Claim 8 (depends on 1) The sign of claim 1, wherein for each of the light modules, the reflective surface is V-shaped. ### Claim 9 (depends on 1) The sign of claim 1, wherein for each of the light modules, the optical device includes optically transparent material with a cavity formed therein, and wherein a side surface of the cavity constitutes the reflective surface. ### Claim 10 (depends on 9) The sign of claim 9, wherein for each of the light modules, the cavity contains a first material having a refractive index that is lower than that of a refractive index of the optically transparent material, and wherein the light output is reflected at the reflective surface by total internal reflection. ### Claim 11 (depends on 1) The sign of claim 1, wherein for each of the light modules, the guide element includes a solid optically transparent material with a cavity formed therein, and wherein the optical device is disposed in the cavity. ### Claim 12 (depends on 1) The sign of claim 1, wherein for each of the light modules, the light output is generally centered around the emission axis, and wherein the reflective surface evenly distributes the reflected light along a plane of the sign interior. ### Claim 13 A sign, comprising: front, back and side surfaces that define an interior of the sign, wherein a plurality of first cavities are formed into the back surface of the sign; a plurality of light emitting modules disposed in the plurality of first cavities, each of the modules including: a light source having an emission axis and for producing at least some light output that is generally parallel to the emission axis, an optical device disposed adjacent the light source having a reflective surface for reflecting the light output in directions that are generally perpendicular to the emission axis, and a guide element disposed adjacent the optical device for coupling the reflected light output into the interior of the sign; wherein the front surface is illuminated by the coupled light output from the light emitting modules. ### Claim 14 (depends on 13) The sign of claim 13, wherein the guide element includes a second cavity formed therein in which the optical device is disposed. ### Claim 15 (depends on 13) The sign of claim 13, further comprising: reflective material disposed along surface portions of the first cavities; and reflective material disposed along the back and side surfaces of the sign. ### Claim 16 (depends on 13) The sign of claim 13, wherein for each of the light modules, the reflective surface is conical in shape. ### Claim 17 (depends on 13) The sign of claim 13, wherein for each of the light modules, the reflective surface is V-shaped. ### Claim 18 (depends on 13) The sign of claim 13, wherein for each of the light modules: the optical device includes optically transparent material with a second cavity formed therein, a side surface of the cavity constitutes the reflective surface, the second cavity contains a first material having a refractive index that is lower than that of a refractive index of the optically transparent material, and the light output is reflected at the reflective surface by total internal reflection.