# US 8,540,408 B2 · Lamp light source with improved heat dissipation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,540,408 B2 - Document ID: US8540408B2 - Status: Granted - Kind: B2 - Application number: 13/511,120 - Filed: 2011-08-29 - Published: 2012-11-15 - Granted: 2013-09-24 - Earliest claimed: 2011-01-25 - Assignees: Panasonic Corporation - Applicants: Kenji Takahashi; Yuji Hosoda; Kazushige Sugita - Inventors: Kenji Takahashi; Yuji Hosoda; Kazushige Sugita - Web page: https://patentgrep.com/patent/US8540408B2 ## CPC - F21V 3/049: {Patterns or structured surfaces for diffusing light, e.g. frosted surfaces} - F21K 9/232: specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb - F21K 9/238: Arrangement or mounting of circuit elements integrated in the light source - F21K 9/60: Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction - F21K 9/68: Details of reflectors forming part of the light source - F21V 17/101: {permanently, e.g. welding, gluing or riveting} - F21V 23/006: {the substrate being distinct from the light source holder} - F21V 29/506: of globes, bowls or cover glasses - F21V 3/02: characterised by the shape - F21V 7/0058: {adapted to cooperate with light sources of shapes different from point-like or linear, e.g. circular light sources} - F21V 7/22: characterised by materials, surface treatments or coatings, e.g. dichroic reflectors - F21Y 2103/33: annular - F21Y 2115/10: Light-emitting diodes [LED] - F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR - F21K: NON-ELECTRIC LIGHT SOURCES USING LUMINESCENCE; LIGHT SOURCES USING ELECTROCHEMILUMINESCENCE; LIGHT SOURCES USING CHARGES OF COMBUSTIBLE MATERIAL; LIGHT SOURCES USING SEMICONDUCTOR DEVICES AS LIGHT-GENERATING ELEMENTS; LIGHT SOURCES NOT OTHERWISE PROVIDED FOR - F21Y: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED ## Abstract A lamp light source comprises: a light-emitting unit having a plurality of semiconductor light-emitting elements arranged as a ring on a front face of a mount so as to principally emit light in a frontal direction; and a circuit unit converting externally-supplied electrical power to cause the semiconductor light-emitting elements to emit the light, wherein a through-hole passes vertically through the light-emitting unit at a point inside the ring of semiconductor light-emitting elements, the circuit unit is at least partly arranged within the through-hole, and a space is provided between the circuit unit and the light-emitting unit. ## Claims ### Claim 1 A lamp light source, comprising: a light-emitting unit having a plurality of semiconductor light-emitting elements arranged as a ring on a front face of a mount so as to principally emit light in a frontal direction; a circuit unit converting externally-supplied electrical power to cause the semiconductor light-emitting elements to emit the light; an envelope including a globe that is diffusive, transmittant, and disposed so as to cover a front side of the light-emitting unit, and a base receiving the externally-supplied electrical power for causing the semiconductor light-emitting elements to emit the light; and a support member arranged at a distance from the light-emitting unit and supporting the circuit unit in relation to the envelope, wherein a through-hole is formed in the light-emitting unit so that the through-hole passes vertically through the light-emitting unit at a point inside the ring of semiconductor light-emitting elements, the circuit unit is at least partly arranged within the through-hole, a space is provided between the circuit unit and the light-emitting unit, and the support member forms at least part of a heat transmission pathway from the circuit unit to the base, the support member thermally connecting the circuit unit and the base. ### Claim 2 A lamp light source, comprising: a light-emitting unit having a plurality of semiconductor light-emitting elements arranged as a ring on a front face of a mount so as to principally emit light in a frontal direction; a circuit unit converting externally-supplied electrical power to cause the semiconductor light-emitting elements to emit the light; an envelope including a globe that is diffusive, transmittant, and disposed so as to cover a front side of the light-emitting unit, and a base receiving the externally-supplied electrical power for causing the semiconductor light-emitting elements to emit the light; and a support member arranged at a distance from the light-emitting unit and supporting the circuit unit in relation to the envelope, wherein a through-hole is formed in the light-emitting unit so that the through-hole passes vertically through the light-emitting unit at a point inside the ring of semiconductor light-emitting elements, the circuit unit is at least partly arranged within the through-hole, a space is provided throughout an entire area between the circuit unit and the light-emitting unit, the space completely separating the circuit unit and the light-emitting unit, and the support member forms at least part of a heat transmission pathway from the circuit unit to the base, the support member thermally connecting the circuit unit and the base. ### Claim 3 (depends on 1) The lamp light source of claim 1, further comprising: a heat conducting member forming at least part of another heat transmission pathway from the circuit unit to the base, the support member thermally connecting the circuit unit and the base. ### Claim 4 (depends on 1) The lamp light source of claim 1 further comprising: a circuit holder made from an insulating member and accommodating the circuit unit, wherein a distance is open between the circuit holder and the light-emitting unit. ### Claim 5 (depends on 1) The lamp light source of claim 1, further comprising: a beam splitter disposed in front of the semiconductor light-emitting elements, reflecting a portion of the light emitted by the semiconductor light-emitting elements diagonally backward to avoid the front face of the mount while allowing another portion of the light to pass, wherein the globe has a treated portion on an inner circumferential surface thereof that is more diffusive than the remainder of the inner circumferential surface, the treated portion corresponding to an area reached by the light reflected by the beam splitter. ### Claim 6 (depends on 1) The lamp light source of claim 1, wherein the semiconductor light-emitting elements are arranged in whole or in part at a slant with respect to a lamp axis. ### Claim 7 (depends on 1) The lamp light source of claim 1, wherein the circuit unit is at least partly arranged within the through-hole such that the light-emitting unit surrounds at least a part of the circuit unit. ### Claim 8 (depends on 1) The lamp light source of claim 1, further comprising: a beam splitter having a substantially annular shape and being disposed in front of the semiconductor light-emitting elements to reflect a portion of the light emitting by the semiconductor light-emitting element diagonally backward while allowing another portion of the light to pass. ### Claim 9 (depends on 3) The lamp light source of claim 3, wherein the circuit unit includes a plurality of electronic components, and the heat conducting member is fixed to a given electronic component producing more heat than other electronic components. ### Claim 10 (depends on 4) The lamp light source of claim 4, wherein the circuit holder is at least partially arranged within the through-hole, and a gap is provided between an outer face of the circuit holder and an inner face of the through-hole. ### Claim 11 (depends on 4) The lamp light source of claim 4, wherein the support member comprises the circuit holder. ### Claim 12 (depends on 4) The lamp light source of claim 4, wherein the envelope further includes a tubular case member that accommodates the light-emitting unit and supports the light-emitting unit in relation to the base, the circuit holder includes (i) a main portion that accommodates at least the part of the circuit unit arranged within the through-hole, and (ii) a tube portion arranged behind the main portion and fixed to the base, when fixed within the main portion of the circuit holder, the circuit unit and the main portion are supported as one by the support member in relation to the envelope, and another gap is provided between the main portion and the tube portion of the circuit holder and the case member. ### Claim 13 (depends on 4) The lamp light source of claim 4, wherein the support member is made of insulating, thermoconductive resin and fills an area between the circuit holder and the base. ### Claim 14 (depends on 4) The lamp light source of claim 4, wherein the circuit unit includes the electronic components, mounted on a front face of a circuit substrate, the circuit substrate is arranged such that a back face thereof is behind the through-hole, and the support member is made of insulating, thermoconductive resin and fills an area between the base and the back face of the circuit substrate. ### Claim 15 (depends on 12) The lamp light source of claim 12, wherein, the globe is fixed to the case member of the envelope with an adhesive applied within an installation groove in a forward edge portion of the case member and dried with an open edge of the globe inserted into the installation groove, and the open edge has a plurality of through-holes formed therethrough in a thickness direction. ### Claim 16 (depends on 12) The lamp light source of claim 12, wherein, the globe is fixed to the case member of the envelope with an adhesive applied within an installation groove in a forward edge portion of the case member and dried with an open edge of the globe inserted into the installation groove, and the open edge has a plurality of dimples formed therein in a thickness direction. ### Claim 17 (depends on 5) The lamp light source of claim 5, wherein the treated portion is a uniform series of semispherical primary dimples formed in the inner circumferential surface of the globe, each having a uniform series of smaller secondary dimples formed therein. ### Claim 18 (depends on 17) The lamp light source of claim 17, wherein each of the primary dimples has a depth of 20 μm to 40 μm, inclusive, and each of the secondary dimples has a depth of 2 μm to 8 μm, inclusive. ### Claim 19 (depends on 2) The lamp light source of claim 2, wherein the circuit unit is at least partly arranged within the through-hole such that he light-emitting unit surrounds at least a part of the circuit unit. ### Claim 20 (depends on 2) The lamp light source of claim 2, further comprising: a beam splitter having a substantially annular shape and being disposed in front of the semiconductor light-emitting elements to reflect a portion of the light emitting by the semiconductor light-emitting element diagonally backward while allowing another portion of the light to pass.