# US 2014/0153256 A1 · Light duct tee extractor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0153256 A1 - Document ID: US20140153256A1 - Status: Published application - Kind: A1 - Application number: 14/009,133 - Filed: 2012-03-27 - Published: 2014-06-05 - Earliest claimed: 2011-04-08 - Assignees: 3M Innovation Properties Company - Inventors: David G. Freier; Thomas R.J. Corrigan - Web page: https://patentgrep.com/patent/US20140153256A1 ## CPC - F21V 7/05: plane - F21S 11/007: {characterised by the means for transmitting light into the interior of a building} - G02B 6/0096: {the lights guides being of the hollow type} - G02B 27/14: operating by reflection only - F21V 2200/40: of hollow light guides - G02B 6/0018: {Redirecting means on the surface of the light guide} - G02B 6/2817: {using reflective elements to split or combine optical signals} - F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR - F21S: NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract The disclosure generally relates to highly efficient light duct light extractors that are capable of extracting a portion of the light propagating within a light duct with nearly 100 percent efficiency. In particular, the described light extractors are configured in a “Tee” shape with a reflective diverter element. ## Claims ### Claim 1 A light duct extractor, comprising: a first light conduit defining a light transport cavity capable of transporting light along a first propagation direction; a second light conduit defining a light diversion cavity, the second light conduit intersecting the first light conduit such that the light transport cavity and the light diversion cavity are contiguous; and a light diverter extending between the light transport cavity and the light diversion cavity, the light diverter comprising a reflective surface disposed at a diverter angle to the first propagation direction, wherein a first light ray propagating within a collimation angle θ of the first propagation direction intercepting the reflective surface, enters the second light conduit and is diverted to a second light ray propagating within the collimation angle θ of a second propagation direction in the second light conduit. ### Claim 2 (depends on 1) The light duct extractor of claim 1, wherein the diverter angle comprises an angle of approximately 45 degrees, and the first propagation direction and the second propagation direction are perpendicular. ### Claim 3 (depends on 1) The light duct extractor of claim 1, wherein each of the first and second light conduits include a first and a second rectangular cross-section, respectively. ### Claim 4 (depends on 3) The light duct extractor of claim 3, wherein each of the first and second rectangular cross-sections are the same. ### Claim 5 (depends on 1) The light duct extractor of claim 1, wherein the light diverter comprises a planar reflector. ### Claim 6 (depends on 5) The light duct extractor of claim 5, wherein the planar reflector comprises a first edge disposed within a region bounded by the intersection of the light transport cavity and the light diversion cavity. ### Claim 7 (depends on 1) The light duct extractor of claim 1, wherein the light diverter comprises a triangular reflector. ### Claim 8 (depends on 7) The light duct extractor of claim 7, wherein the triangular reflector comprises: a first side disposed within a region bounded by the intersection of the light transport cavity and the light diversion cavity, the first side positioned parallel to the first propagation direction; and a first edge formed by the intersection of the first side and the reflective surface, wherein the first edge is disposed within the region bounded by the intersection of the light transport cavity and the light diversion cavity. ### Claim 9 (depends on 1) The light duct extractor of claim 1, wherein the collimation angle is between about 0 degrees and about 30 degrees. ### Claim 10 (depends on 1) The light duct extractor of claim 1, wherein the collimation angle is between about 10 degrees and about 20 degrees. ### Claim 11 (depends on 1) The light duct extractor of claim 1, wherein the collimation angle is about 18.4 degrees. ### Claim 12 (depends on 1) The light duct extractor of claim 1, wherein a first edge of the light diverter is disposed within a boxed region defined by an input cross section of the first light conduit, an output cross-section of the first light conduit, and a diverter cross section of the second light conduit. ### Claim 13 (depends on 12) The light duct extractor of claim 12, wherein a second edge of the light diverter is disposed in the light diversion cavity outside of the boxed region. ### Claim 14 (depends on 12) The light duct extractor of claim 12, wherein the light diverter comprises a triangular reflector having a first side disposed in the boxed region parallel to the first propagation direction, and an apex disposed in the light diversion cavity outside of the boxed region. ### Claim 15 (depends on 12) The light duct extractor of claim 12, wherein the light diverter comprises an isosceles-shaped triangular reflector having a base disposed in the boxed region parallel to the first propagation direction, and an apex centered in the light diversion cavity outside of the boxed region. ### Claim 16 (depends on 12) The light duct extractor of claim 12, wherein at least two of the input cross section of the first light conduit, the output cross-section of the first light conduit, and the input cross section of the second light conduit have the same dimensions. ### Claim 17 (depends on 12) The light duct extractor of claim 12, wherein the input cross section of the second light conduit is smaller than the input cross section of the first light conduit. ### Claim 18 (depends on 1) The light duct extractor of claim 1, wherein the diverter angle and the reflective surface extending into the light transport cavity can be independently adjusted so that a variable portion of light travelling though the light transport cavity can be diverted to the light diversion cavity. ### Claim 19 (depends on 1) The light duct extractor of claim 1, wherein the first propagation direction and the second propagation direction are perpendicular to each other.