WO2011040937A1 - Source de lumière à semi-conducteurs et procédé pour produire une source de lumière à semi-conducteurs - Google Patents

Source de lumière à semi-conducteurs et procédé pour produire une source de lumière à semi-conducteurs Download PDF

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Publication number
WO2011040937A1
WO2011040937A1 PCT/US2009/067523 US2009067523W WO2011040937A1 WO 2011040937 A1 WO2011040937 A1 WO 2011040937A1 US 2009067523 W US2009067523 W US 2009067523W WO 2011040937 A1 WO2011040937 A1 WO 2011040937A1
Authority
WO
WIPO (PCT)
Prior art keywords
reflector
semiconductor chip
light source
light pipe
semiconductor
Prior art date
Application number
PCT/US2009/067523
Other languages
English (en)
Inventor
Christopher Eichelberger
Michael Godwin
Original Assignee
Osram Opto Semiconductors Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Osram Opto Semiconductors Gmbh filed Critical Osram Opto Semiconductors Gmbh
Publication of WO2011040937A1 publication Critical patent/WO2011040937A1/fr

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Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0005—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being of the fibre type
    • G02B6/0006—Coupling light into the fibre
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B19/00—Condensers, e.g. light collectors or similar non-imaging optics
    • G02B19/0004—Condensers, e.g. light collectors or similar non-imaging optics characterised by the optical means employed
    • G02B19/0019—Condensers, e.g. light collectors or similar non-imaging optics characterised by the optical means employed having reflective surfaces only (e.g. louvre systems, systems with multiple planar reflectors)
    • G02B19/0023—Condensers, e.g. light collectors or similar non-imaging optics characterised by the optical means employed having reflective surfaces only (e.g. louvre systems, systems with multiple planar reflectors) at least one surface having optical power
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B19/00—Condensers, e.g. light collectors or similar non-imaging optics
    • G02B19/0033—Condensers, e.g. light collectors or similar non-imaging optics characterised by the use
    • G02B19/0047—Condensers, e.g. light collectors or similar non-imaging optics characterised by the use for use with a light source
    • G02B19/0052—Condensers, e.g. light collectors or similar non-imaging optics characterised by the use for use with a light source the light source comprising a laser diode

Definitions

  • the semiconductor light source comprises a carrier having a main area.
  • the function of the carrier is to provide mechanical stability for the light source.
  • the carrier can serve as an electrical connection means.
  • the carrier can be a printed circuit board, a circuit board, a metal core board, or a ceramic board with conductor paths on it.
  • the carrier has a low thermal resistance.
  • an average thermal conductivity of the carrier is equal to or exceeds 40 W/ (m K) , especially 100 W/ (m K) .
  • the semiconductor light source comprises at least one optoelectronic semiconductor chip.
  • the semiconductor chip is mounted on the main area of the carrier and is capable of emitting ultraviolet or visible radiation during operation of the light source.
  • the semiconductor chip is a thin-film chip with a thickness of at most 200 urn, especially of at most 20 ⁇ with regard to epitaxially grown layers.
  • the semiconductor chip could be formed as described in the documents WO 2005/081319 Al or DE 10 2007 004 304 Al, of which the disclosure content relating to the semiconductor chip is hereby incorporated by back-reference.
  • the semiconductor chip could be a light-emitting diode, a laser diode or a super-luminescence diode.
  • the semiconductor light source comprises a reflector that is arranged on the main area of the carrier.
  • the reflector partially or completely surrounds the semiconductor chip in a lateral direction.
  • the reflector is fashioned to reflect radiation emitted by the semiconductor chip.
  • a material of the carrier preferably differs from a material of the reflector.
  • the carrier and the reflector are manufactured separately.
  • a light pipe is arranged downstream the semiconductor chip seen in a direction of main emittance of the semiconductor chip. Via the light pipe, the radiation generated by the semiconductor can be led to various places of, for instance, a dashboard of a car.
  • the light guide is a multi-mode light guide. In other words, an effective light guiding area of the light pipe is comparably big, for example exceeding 3000 ⁇ 2 or 5000 um ⁇ , and supports the guidance of a large number of transversal modes.
  • the light pipe is spaced apart from the semiconductor chip.
  • the light pipe is not in direct contact with the semiconductor chip.
  • the light pipe is fixed relative to the semiconductor chip by means of the reflector.
  • the light pipe and the reflector are directly mechanically connected with each other.
  • the fixture in between the light pipe and the reflector can be reversible or irreversible.
  • an average width of a core of the light pipe at the side of the reflector remote from the semiconductor chip matches an average inner diameter of the reflector at this side with a tolerance of at most 25%.
  • the tolerance is at most 15%, especially at most 10%, particularly preferable at most 5%.
  • an average width of the core of the light pipe is essentially equal to the average inner diameter of the reflector, on a side of the reflector remote from the semiconductor chip.
  • the core can be a part of the light pipe that is capable of transmitting and guiding light.
  • the semiconductor light source comprises a carrier having a main area and an optoelectronic semiconductor chip arranged on the main area of the carrier.
  • the semiconductor chip is suited, to emit visible and/or ultraviolet radiation in operation of the light source.
  • a reflector of the light source is mounted on the main area. The reflector partially or completely surrounds the semiconductor chip in a lateral direction.
  • a light pipe of the light source is arranged downstream the semiconductor chip seen in a direction of main emittance of the semiconductor chip. Furthermore, the light pipe is spaced apart from the semiconductor chip.
  • a fixture of the light pipe to the other parts of the light source like the carrier is realized by means of the reflector.
  • an average width of a core of the light pipe at a side of the reflector remote from the semiconductor chip matches an average inner diameter of the reflector at this side with a tolerance of at most 25%.
  • the reflector especially the inner surfaces of the reflector, are shaped parabolic, elliptic and/or hyperbolic.
  • the reflector can be a compound parabolic reflector, in short CPC, a compound elliptical concentrator, in short CEC, or a compound hyperbolic concentrator, in short CHC.
  • an average inner diameter of the reflector can increase with increasing distance from the semiconductor chip until the light entrance surface of the light pipe.
  • the inner diameter of the reflector can be monotonxcally increasing or strictly increasing.
  • the core of the light pipe is composed of or comprises a homogenously distributed transparent material.
  • a refractive index of the core can be constant, at least in a lateral direction perpendicular to a direction of main guidance.
  • the core consists of a plastic or of a glass.
  • an average width of the core exceeds an average diameter of the semiconductor chip.
  • the reflector has inner surfaces that are reflective for the generation emitted by the semiconductor chip.
  • An average reflectance of the inner surfaces can exceed 75%, preferably 90%.
  • the core of the light pipe is in direct contact with a coating.
  • the coating can consist of or can comprise a reflective light-proof material.
  • the coating is realized by a thin metallic film with a thickness in the range between 1 um and 50 um, inclusive.
  • a reflectance of the coating with regard to the radiation emitted by the semiconductor is at least 70%, preferably at least 80%, particularly preferably at least 95%.
  • the light pipe is no fiber optics.
  • a guiding of the radiation in the light pipe is not based on total reflection but on normal reflection.
  • a real part of the refractive index of the coating preferably exceeds a real part of the refractive index of the core.
  • the reflector further comprises protrusions, wherein the protrusions completely or partially penetrate through the carrier.
  • the reflector can be fastened to the carrier.
  • the protrusions extend into recesses of the carrier.
  • lateral surfaces of the semiconductor chip are partially or completely covered by a material of the reflector.
  • a semiconductor material of the semiconductor chip can be in direct physical contact with a material of the reflector, especially with a plastic .
  • a cavity is formed by the carrier, the reflector and the light pipe. Especially, the cavity is defined exclusively by these elements of the light source.
  • the at least one semiconductor chip is preferably completely arranged within this cavity.
  • the cavity can be fashioned in an air-tight manner. In this case, the semiconductor chip and the light entrance surface of the light pipe can be sealed against the environment by the carrier, the reflector and the light pipe.
  • the reflector of the light source is formed by a two-component injection molding. Then, the reflector preferably consists of or comprises two or more then two different plastics .
  • the semiconductor light source further comprises a surface-mountable chip housing. The at least one semiconductor chip is arranged and mounted in the chip housing. The chip housing further can be directly mounted on the main area of the carrier by means of a surface mount technology such as a soldering.
  • the chip housing can be completely surrounded by the reflector in a lateral direction. It is also possible that the chip housing is spaced apart from a material of the reflector, especially in a lateral direction.
  • the chip housing can contain one or more semiconductor chips .
  • a method for producing a semiconductor light source is provided. With this method, especially a - -
  • semiconductor light source as described in connection with at least one of the preceding aspects can be manufactured.
  • the subject matter disclosed for the semiconductor light source is also disclosed for the method and vice-versa.
  • the method for producing the semiconductor light source comprises the steps:
  • the steps of the method are performed in the sequence given above, although deviations there from can be possible.
  • FIGs. 1 to 3, 6 and 7 show schematic sectional illustrations of semiconductor light sources of exemplary embodiments and FIGs. 4 and 5 show schematic steps of methods for producing exemplary embodiments of semiconductor light sources.
  • FIG. 1A An exemplary embodiment of a semiconductor light source 1 is illustrated in FIG. 1.
  • FIG. 1A a sectional view of a reflector 4 of the light source 1 is drafted
  • FIG. IB a sectional view of the whole light source 1 can be seen.
  • the reflector 4 comprises an inner surface 45 of a parabolic shaped part 43. Moreover, the reflector 4 comprises fastening means 41 and protrusions 44.
  • the fastening means 41 that as an example can be a screw thread or a snap fit
  • a light pipe 5 is affixed to the reflector 4.
  • the protrusions 44 the reflector 4 is fastened to a carrier 2 of the light source 1.
  • the protrusions 44 can extend into recesses of the carrier 2, not drawn in FIG. 1.
  • an optoelectronic semiconductor chip 3 is mounted on a main area 20 of the carrier 2. Radiation that is emitted during operation by the semiconductor 3, is led to a light entrance surface 50 of the light pipe 5.
  • the parabolic shaped part 43 of the reflector 4 shows a high reflectance.
  • a diffuse reflectance contributes to an overall reflectance of the inner surface 45 only to a minor extent, for example to at most 40%, preferably to at most 20%.
  • the reflector 4 can consist of or can comprise a bright and/or white plastic material.
  • the inner surface 45 of the reflector 4 is formed from white plastic.
  • the inner surface 45 can be free from a reflective coating.
  • the reflector 4 can be one- pieced and thus can be manufactured cost-effectively.
  • the inner surface 45 is declared as parabolic shaped, besides being a compound parabolic concentrator, in short CPC, the reflector can also be a compound elliptical concentrator, in short CEC, or a compound hyperbolic concentrator, in short CHC .
  • a distance L between the radiation exit surface 30 of the semiconductor chip 3 and the light entrance surface 50 of the light pipe is at least three times and at most eight times, inclusive, an average edge length E of the semiconductor chip.
  • the semiconductor chip 3 is considerably spaced apart from the light pipe 5.
  • an average diameter D of the reflector at a side 40 remote from the semiconductor chip 3 resembles an average width W of the light pipe 5 at this side 40.
  • essentially the whole reflector 4 is filled by the light pipe 5 on the side 40 remote from the semiconductor chip 3.
  • the semiconductor chip 3 can be directly mounted on the main area 20 of the carrier 2 by means of a surface mount technology, especially by means of a soldering.
  • the semiconductor chip 3 can be free of a housing. Then, for instance, the radiation exit surface 30 is not followed by a lens or an encapsulant material. It is possible that the semiconductor chip 3 includes a luminescence conversion material. - -
  • the light pipe 5 can be screwed to the reflector 4.
  • the light source 1 can comprise a gasket, not shown in the figures.
  • FIG. 2A Another exemplary embodiment of the light source 1 is depicted in FIG. 2.
  • FIG. 2B Another exemplary embodiment of the light source 1 is depicted in FIG. 2.
  • FIG. 2A a sectional view of the light source 1 is shown whereas in FIG. 2B, a sectional view of the light pipe 5 only is illustrated.
  • the protrusions 44 penetrate completely through the carrier 2 and are expanded headlike on a side of the carrier 2 remote from the semiconductor chip 3.
  • the parabolic shaped part 43 of the reflector 4 begins immediately at the main area 20 of the carrier 2.
  • radiation emitted, for example, on lateral surfaces 35 of the semiconductor chip 3 can be efficiently reflected by the reflector 4 into a direction to the light pipe 5.
  • the light pipe 5 can comprise a core 51 that consists of a homogenously distributed material that is transparent for the radiation emitted by the semiconductor chip 3.
  • the core 51 can consist of at least one transparent plastic or of at least one glass.
  • the core 51 can be coated with a reflective coating 52, for example made of a metal. Lateral surfaces of the light pipe 5 near the light entrance surface 50 are provided with fastening means 53 by which the light pipe 5 can be fastened to the fastening means 41 of the reflector 4 reversibly or irreversibly.
  • the light entrance surface 50 is coated by an anti- reflection coating 54.
  • the light pipe is for example molded or extruded in an acrylic material, e.g. Polymethylmethacrylate, in short PM A, with or without a coating or cladding. Other materials which are transparent in the visible radiation spectrum like glass or other plastics can also be used. PMMA is, however, preferred due to excellent optical properties and low cost.
  • a silicone For the production of a flexible light pipe 5, e.g. a silicone can be used.
  • Suitable materials for the coating of the light pipe and/or the reflector are metals, e.g. aluminum.
  • the coating can be applied via vacuum metallization, for example. It is also possible to use white plastic for the coating and/or the reflector.
  • the carrier 2 has for example the following dimensions:
  • the chip 3 has an area for example between at least 500 ⁇ 2 and at most 6000 ⁇ 2 , inclusive, preferably between at least 1000 urn 2 and at most 4000 ⁇ 2 , inclusive.
  • the reflector 4 and the light pipe 5 are drawn rotationally symmetric with regard to a direction M of main emittance of the semiconductor chip 3.
  • the reflector 4 and/or the light pipe 5 can be shaped non-rotationally symmetric with regard to the direction M of main emittance.
  • a part of the light guide 51 that is located in the reflector 4 can be shaped rotationally symmetric as well as the reflector 4 itself whereas an end of the light pipe 5 remote from the reflector 4 can be shaped line-like in order to illuminate, for example, a display or a panel.
  • the light guide 51 has for example a diameter between at least 5 mm and at most 20 mm, inclusive, preferably between at least 8 mm and at most 13 mm, inclusive.
  • the dimensions of the reflector 4 can be the same as the dimensions of the light guide 51.
  • the semiconductor light source 1 can comprise more than one semiconductor chip 3.
  • a plurality of semiconductor chips 3 can be arranged symmetrically with regard to a symmetry axis of the reflector 4 in a direction perpendicular to the carrier 2.
  • the reflector 4 of the semiconductor light source 1 comprises a base part 42 and a parabolic shaped part 43.
  • the inner surface 45 is oriented essentially perpendicular with regard to the main area 20 of the carrier 2. It is possible that lateral surfaces of the carrier 2 are flush with lateral surfaces of the reflector 4.
  • the parabolic shaped part 43 begins at a distance from the main area 20, being at least the distance from the radiation exit surface 30 to the main area 20 of the carrier 2.
  • the light pipe 5 is not drawn in FIG. 3.
  • FIG. 4A A method for producing the semiconductor . light source 1 is schematically illustrated in FIG. 4.
  • the parabolic shaped part 43 of the reflector 4 is injection molded in a mold 8a-c.
  • the mold 8a corresponds to an outer geometry of the reflector 4 to be molded.
  • the inner part 8b of the mold has the same form as the parabolic shaped part 43 and the inner surfaces 45 of the reflector 4, respectively.
  • a third part 8c of the mold the molding cavity is closed.
  • the mold part 8c is removed and replaced by the carrier 2 with the semiconductor chip 3 mounted on the main area 20.
  • the carrier 2 forms a part of the mold during the molding.
  • the radiation exit surface 30 of the semiconductor chip 3 can be in direct contact with the inner mold 8b.
  • the base part 42 of the reflector 4 is molded. In a direction perpendicular to the main area 20, a height of the base part 42 preferably is equal to or exceeds a thickness of the semiconductor chip 3.
  • the reflector 4 can be molded by a two-component injection molding. Then, the plastics of the base part
  • the light source 1 is finished by attaching the light pipe 5 to the reflector 4. This can be performed, for example, by means of pressing the light pipe 5 into the reflector 4.
  • the reflector 4 is molded first. Subsequently, the light pipe 5 is attached to the reflector 4. Preferably afterwards, the reflector 4 is attached to the carrier 2 by plastically deforming the protrusions 44.
  • FIG. 6 single rays R of the radiation emitted by the semiconductor chip 3 are illustrated. Furthermore, according to FIG. 6, the semiconductor chip 3 is housed in a chip housing 7 that is spaced apart from the inner surface 45 of the reflector 4. The radiation emitted by the semiconductor chip 3 can be pre-focused by the housing 7.
  • FIG. 7 another exemplary embodiment of the semiconductor light source 1 is shown in sectional three-dimensional views, compare FIGs . 7A and 7B. Only the reflector 4 is depicted in FIG. 7C, also in a sectional three-dimensional view.
  • the invention is not restricted to the exemplary embodiments by the description on the basis of the -
  • the invention encompasses any new feature and also any combination of features, which in particular comprises any combination of features in the patent claims and any combination of features in the exemplary embodiments, even if this feature or this combination itself is not explicitly specified in the patent claims or exemplary embodiments .

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Led Device Packages (AREA)

Abstract

L'invention, selon au moins un aspect, porte sur une source de lumière à semi-conducteurs (1), qui comprend un support (2) comportant une zone principale (20) et une puce à semi-conducteurs optoélectronique (3). La puce à semi-conducteurs (3) est appropriée pour émettre un rayonnement visible et/ou ultraviolet. De plus, un réflecteur (4) est monté sur la zone principale (20). Le réflecteur entoure la puce à semi-conducteurs dans une direction latérale. Un tuyau de lumière (5) est disposé en aval de la puce à semi-conducteurs, dans une direction (M) d'émission principale de la puce à semi-conducteurs. De plus, le tuyau de lumière est espacé de la puce à semi-conducteurs. Une monture du tuyau de lumière est réalisée à l'aide du réflecteur. De plus, une largeur moyenne (W) d'un cœur (51) du tuyau de lumière d'un côté (40) du réflecteur distant de la puce à semi-conducteurs correspond à un diamètre interne moyen (D) du réflecteur de ce côté, avec une tolérance maximale de 25 %.
PCT/US2009/067523 2009-09-30 2009-12-10 Source de lumière à semi-conducteurs et procédé pour produire une source de lumière à semi-conducteurs WO2011040937A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US24736909P 2009-09-30 2009-09-30
US61/247,369 2009-09-30

Publications (1)

Publication Number Publication Date
WO2011040937A1 true WO2011040937A1 (fr) 2011-04-07

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Application Number Title Priority Date Filing Date
PCT/US2009/067523 WO2011040937A1 (fr) 2009-09-30 2009-12-10 Source de lumière à semi-conducteurs et procédé pour produire une source de lumière à semi-conducteurs

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102013004773A1 (de) 2013-03-20 2014-09-25 Jenoptik Polymer Systems Gmbh Beleuchtungsmodul

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4191446A (en) * 1974-12-16 1980-03-04 U.S. Philips Corporation Directional coupling-device for multi-mode optical fibres
US5343330A (en) * 1991-09-25 1994-08-30 Rousseau Sauve Warren Inc. Double refraction and total reflection solid nonimaging lens
US20060133740A1 (en) * 2004-11-22 2006-06-22 Hiromi Nakanishi Optical receptacle having stub capable of enhancing optical coupling efficiency and optical module installing the same
US20060188836A1 (en) * 1998-01-20 2006-08-24 Kerr Corporation Apparatus and method for curing materials with light radiation
US20070263383A1 (en) * 2004-09-24 2007-11-15 Koninklijke Philips Electronics, N.V. Illumination System
JP2008041843A (ja) * 2006-08-03 2008-02-21 Sharp Corp 半導体発光装置および半導体発光装置の製造方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4191446A (en) * 1974-12-16 1980-03-04 U.S. Philips Corporation Directional coupling-device for multi-mode optical fibres
US5343330A (en) * 1991-09-25 1994-08-30 Rousseau Sauve Warren Inc. Double refraction and total reflection solid nonimaging lens
US20060188836A1 (en) * 1998-01-20 2006-08-24 Kerr Corporation Apparatus and method for curing materials with light radiation
US20070263383A1 (en) * 2004-09-24 2007-11-15 Koninklijke Philips Electronics, N.V. Illumination System
US20060133740A1 (en) * 2004-11-22 2006-06-22 Hiromi Nakanishi Optical receptacle having stub capable of enhancing optical coupling efficiency and optical module installing the same
JP2008041843A (ja) * 2006-08-03 2008-02-21 Sharp Corp 半導体発光装置および半導体発光装置の製造方法

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102013004773A1 (de) 2013-03-20 2014-09-25 Jenoptik Polymer Systems Gmbh Beleuchtungsmodul

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