Light-emitting apparatus
09869454 ยท 2018-01-16
Assignee
Inventors
Cpc classification
F21Y2115/30
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21V13/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21V7/0066
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21V19/0015
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21V13/14
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21V9/40
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21S41/16
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21S41/10
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21Y2115/10
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21V5/08
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21S41/176
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21K9/64
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F21V13/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21V5/08
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21V13/12
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F21K9/64
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
Embodiments provide a light-emitting apparatus including at least one light source, a wavelength converter configured to convert a wavelength of light emitted from the light source, a reflector configured to reflect the light having the wavelength converted in the wavelength converter and light having an unconverted wavelength, and a refractive member disposed in a light passage space between the reflector and the wavelength converter, the refractive member being configured to emit the reflected light.
Claims
1. A light-emitting apparatus comprising: at least one light source; a wavelength converter configured to convert a wavelength of light emitted from the light source; a reflector configured to reflect the light having the wavelength converted in the wavelength converter and light having an unconverted wavelength; a refractive member disposed in a light passage space between the reflector and the wavelength converter, the refractive member being configured to emit the reflected light; and a base substrate disposed to be opposite to the reflector, wherein the refractive member includes: a rounded first surface disposed to face the reflector; a second surface having a first portion disposed to face the wavelength converter, and a second portion excluding the first portion; and a third surface for emission of the reflected light, wherein the base substrate includes first and second areas adjacent to each other, wherein the first area corresponds to an area excluding the second area, or the first area corresponds to an area facing the second portion of the second surface of the refractive member, and wherein the second area corresponds to an area, in which the wavelength converter is disposed.
2. The apparatus according to claim 1, wherein the base substrate is disposed to be opposite to the reflector with the refractive member interposed therebetween.
3. The apparatus according to claim 1, wherein the second area of the base substrate includes a first through-hole for passage of the light emitted from the light source, and the wavelength converter is located in the first through-hole.
4. The apparatus according to claim 1, wherein the reflector includes a second through-hole for passage of the light emitted from the light source.
5. The apparatus according to claim 3, wherein the first through-hole is located closer to the first surface of the refractive member than the third surface.
6. The apparatus according to claim 4, wherein the reflector has one end coming into contact with the third surface of the refractive member and the other end coming into contact with the base substrate, and a first distance from the second through-hole to the one end of the reflector is greater than a second distance from the second through-hole to the other end of the reflector.
7. The apparatus according to claim 1, further comprising a first reflective layer disposed between at least a part of the second portion of the refractive member and the first area of the base substrate.
8. The apparatus according to claim 4, wherein the second area of the base substrate includes a recess for arrangement of the wavelength converter.
9. The apparatus according to claim 8, further comprising a second reflective layer disposed in the recess between the wavelength converter and the base substrate.
10. The apparatus according to claim 4, wherein the wavelength converter is disposed on the second area of the base substrate so as to be rotatable to face the second through-hole.
11. The apparatus according to claim 1, wherein at least one of the second portion of the refractive member and the first area of the base substrate has a pattern.
12. The apparatus according to claim 1, wherein the reflector and the refractive member are integrated with each other.
13. The apparatus according to claim 1, further comprising an anti-reflective film disposed on the third surface of the refractive member.
14. The apparatus according to claim 1, wherein the reflector includes a metal layer coated on the first surface of the refractive member.
15. The apparatus according to claim 1, further comprising a first adhesive part disposed between the first portion of the second surface of the refractive member and the wavelength converter.
16. The apparatus according to claim 1, further comprising a second adhesive part disposed between the second portion of the second surface of the refractive member and the first area of the base substrate.
17. The apparatus according to claim 1, wherein the at least one light source includes, a plurality of light sources, and wherein the light-emitting apparatus further comprises a circuit board for mounting of the light sources.
18. The apparatus according to claim 17, further comprising a radiator attached to a rear surface of the circuit board or a rear surface of the base substrate.
19. The apparatus according to claim 17, further comprising: at least one lens unit configured to focus light emitted from the plurality of light sources and to emit the focused light through the first or second through-hole; and a mirroring unit arranged between the at least one lens unit and the first or second through-hole, the mirroring unit being configured to reflect the focused light from the at least one lens unit and to provide the reflected light into the first or second through-hole.
20. The apparatus according to claim 19, wherein the at least one lens unit comprises a first sub lens and a second sub lens, wherein the first sub, lens is arranged between the second sub lens and the first or second through-hole, wherein a number of the second sub lens is equal to a number of the plurality of light sources, and wherein each of the second sub lens is arranged between each of the plurality of light sources and the first sub lens.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Arrangements and embodiments may be described in detail with reference to the following drawings in which like reference numerals refer to like elements and wherein:
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DESCRIPTION OF SPECIFIC EMBODIMENTS
(25) Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings to aid in understanding of the embodiments. However, the embodiments may be altered in various ways, and the scope of the embodiments should not be construed as limited to the following description. The embodiments are intended to provide those skilled in the art with more complete explanation.
(26) In the following description of the embodiments, it will be understood that, when each element is referred to, as being formed on or under the other element, it can be directly on or under the other element or be indirectly formed with one or more intervening elements therebetween. In addition, it will also be understood that on or under the element may mean an upward direction and a downward direction of the element.
(27) In addition, the relative terms first, second, upper, lower and the like in the description and in the claims may be used to distinguish between any one substance or element and other substances or elements and not necessarily for describing any physical or logical relationship between the substances or elements or a particular order.
(28) In the drawings, the thickness or size of each layer (or each portion) may be exaggerated, omitted or schematically illustrated for clarity and convenience. In addition, the size of each constituent element does not wholly reflect an actual size thereof.
(29) Hereinafter, light-emitting apparatuses 100A to 100I according to the embodiments will be described with reference to the accompanying drawings. For convenience, although the light-emitting apparatuses 100A to 100I will be described using the Cartesian coordinate system (comprising the x-axis, the y-axis, and the z-axis), of course, it may be described using other coordinate systems. In addition, although the x-axis, the y-axis, and the z-axis in the Cartesian coordinate system are perpendicular to one another, the embodiments are not limited thereto. That is, the x-axis, the y-axis, and the z-axis may cross one another, rather than being perpendicular to one another.
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(31) The light-emitting apparatus 100A of one embodiment may include a light source 110, a wavelength converter 120, a reflector 130A, a refractive member 140A, a substrate 150A, a first reflective layer 160, a first adhesive part 170, and a light transmitting layer 180.
(32) The light source 110 serves to emit light. Although the light source 110 may include at least one of Light-Emitting Diodes (LEDs) or Laser Diodes (LDs), the embodiment is not limited as to the kind of the light source 110.
(33) Generally, the viewing angle of LEDs is wider than the viewing angle of LDs. Thus, LDs having a narrower viewing angle than LEDs may be advantageous in terms of the introduction of light into a first through-hole PT1. However, in the case where an optical system (not illustrated) capable of reducing the viewing angle is located between the light source 110, i.e. the LEDs and the first through-hole PT1, the optical system may reduce the viewing angle of light emitted from the LEDs so as to introduce the light into the first through-hole PT1. As such, the LEDs may be used as the light source 110.
(34) In the case of
(35) In addition, although the light emitted from the light source 110 may have any peak wavelength in the wavelength band from 400 nm to 500 nm, the embodiment is not limited as to the wavelength band of the emitted light. The light source 110 may emit light having a Spectral Full Width at Half Maximum (SFWHM) of 10 nm or less. The SFWHM corresponds to the width of a wavelength depending on intensity. However, the embodiment is not limited to any specific value of the SFWHM. In addition, although the FWHM of light, emitted from the light source 110 and introduced into the wavelength converter 120, i.e. the size of light beams may be 1 nm or less, the embodiment is not limited thereto.
(36) In addition, the light transmitting layer 180 may be additionally disposed in a path along which the light emitted from the light source 110 passes toward the wavelength converter 120. That is, the light transmitting layer 180 may be located between the light source 110 and the first through-hole PT1. The light transmitting layer 180 may include a transparent medium, the index of refraction of which is 1, the same as that of air, or may include a transparent medium, the index of refraction of which is greater than 1 and equal to or less than 2. In some cases, the light-emitting apparatus 100A may not include the light transmitting layer 180.
(37) In the case of
(38) The light source 110 may be spaced apart from the wavelength converter 120 (or the first through-hole PT1) by a first distance d1. When the first distance d1 is small, the wavelength converter 120 may be affected by heat generated from the light source 110. Therefore, although the first distance d1 may be 10 m or more, the embodiment is not limited thereto.
(39) Meanwhile, the wavelength converter 120 may convert the wavelength of the light emitted from the light source 110. While the light emitted from the light source 110 is introduced into the first through-hole PT1 and passes through the wavelength converter 120, the wavelength of the light may vary. However, not all of the light that has passed through the wavelength converter 120 may be wavelength-converted light.
(40) As the wavelength of the light emitted from the light source 110 is converted by the wavelength converter 120, white light or light having a desired color temperature may be emitted from the light-emitting apparatus 100A. To this end, the wavelength converter 120 may include phosphors, for example, at least one of ceramic phosphors, lumiphors, and YAG single-crystals. Here, the term lumiphors means a luminescent material or a structure including a luminescent material.
(41) In addition, light having a desired color temperature may be emitted from the light-emitting apparatus 100A via adjustment in, for example, the concentration, particle size, and particle-size distribution of various materials included in the wavelength converter 120, the thickness of the wavelength converter 120, the surface roughness of the wavelength converter 120, and air bubbles. For example, the wavelength converter 120 may convert the wavelength band of light having a color temperature within a range from 3000K to 9000K. That is, although the light, the wavelength of which has been converted by the wavelength converter 120, may be within the color temperature range from 3000K to 9000K, the embodiment is not limited thereto.
(42) The wavelength converter 120 may be any of various types. For example, the wavelength converter 120 may be any of three types, i.e. a Phosphor-In-Glass (PIG) type, a polycrystalline type (or ceramic type), and a single-crystalline type.
(43) The wavelength converter 120 may be disposed on the base substrate 150A. The base substrate 150A may include a first area A1 and a second area A2. The first area A1 of the base substrate 150A may be defined as the area that faces a second portion S2-2, excluding a first portion S2-1, at a second surface S2 of the refractive member 140A which will be described below. Alternatively, in
(44) The base substrate 150A may directly contact the refractive member 140A as exemplarily illustrated in
(45) The reflector 130A may reflect light, the wavelength of which has been converted in the wavelength converter 120 as well as light, the wavelength of which has not been converted in the wavelength converter 120. In addition, the reflector 130A may include at least one selected, based on the desired illuminance distribution, from an aspherical surface, a freeform curved surface, a Fresnel lens, and a Holography Optical Element (HOE). Here, the freeform curved surface may be a form provided with curvilinear surfaces in various shapes.
(46) When the Fresnel lens is used as the reflector 130A, the Fresnel lens may serve as a reflector 130A that reflects light, the wavelength of which has been converted in the wavelength converter 120, as well as light, the wavelength of which has not been converted.
(47) Meanwhile, the refractive member 140A may fill the space for the passage of light between the reflector 130A and the wavelength converter 120 and serve to refract the light introduced into the first through-hole PT1 or to emit the light reflected by the reflector 130A. The light emitted from the light source 110 is introduced through the first through-hole PT1, and thereafter passes through the wavelength converter 120. At this time, when the light, directed to the reflector 130A after passing through the wavelength converter 120, is introduced into the refractive member 140A by way of the air, the light may be refracted in the refractive member 140A due to the difference in the index of refraction between the air and the refractive member 140A (or the wavelength converter 120).
(48) Therefore, according to the embodiment, the refractive member 140A is disposed to fill the entire space, through which the light is directed toward the reflector 130A after passing through the wavelength converter 120, thereby ensuring that no air is present in the space through which the light, having passed through the wavelength converter 120, passes. As a result, the light having passed through the wavelength converter 120 may travel to the reflector 130A by way only of the refractive member 140A, without passing through the air, and the light reflected by the reflector 130A may be emitted to the air through a third surface S3, which will be described hereinafter, after passing through the refractive member 140A.
(49) In addition, the smaller the difference n between the first index of refraction n1 of the wavelength converter 120 and the second index of refraction n2 of the refractive member 140A, the greater the improvement in the light extraction efficiency of the light-emitting apparatus 100A. However, when the difference n between the first and second indices of refraction n1 and n2 is large, the improvement in the light extraction efficiency of the light-emitting apparatus 100A may be reduced.
(50) The following Table 1 represents the relationship between the difference n between the first index of refraction n1 and the second index of refraction n2 and light extraction efficiency.
(51) TABLE-US-00001 TABLE 1 n1 n2 n Ext(%) Ext(%) 1.4 1.0 0.4 30.01 0.00 (202, 212 in 1.1 0.3 38.14 8.13 FIGS. 4A, 4B) 1.2 0.2 48.49 18.48 1.3 0.1 62.88 32.87 1.4 0 100.00 69.99 1.6 1.0 0.6 21.94 0.00 (204, 214 in 1.1 0.5 27.38 5.44 FIGS. 4A, 4B) 1.2 0.4 33.86 11.92 1.3 0.3 41.70 19.77 1.4 0.2 51.59 29.65 1.5 0.1 65.20 43.26 1.6 0 100.00 78.06 1.8 1.0 0.8 16.85 0.00 (206, 216 in 1.1 0.7 20.85 3.99 FIGS. v4A, 4B) 1.2 0.6 25.46 8.61 1.3 0.5 30.83 13.98 1.4 0.4 37.15 20.29 1.5 0.3 44.72 27.87 1.6 0.2 54.19 37.34 1.7 0.1 67.13 50.28 1.8 0 100.00 83.15 2.0 1.0 1.0 13.40 0.00 (208, 218 in 1.1 0.9 16.48 3.09 FIGS. 4A, 4B) 1.2 0.8 20.00 6.60 1.3 0.7 24.01 10.61 1.4 0.6 28.59 15.19 1.5 0.5 33.86 20.46 1.6 0.4 40.00 26.60 1.7 0.3 47.32 33.92 1.8 0.2 56.41 43.01 2.0 0 100.00 86.60
(52) Here, Ext is light extraction efficiency, and Ext is variation in light extraction efficiency Ext.
(53)
(54) Referring to Table 1 and
(55) The first index of refraction n1 may be changed according to the shape of the wavelength converter 120. When the wavelength converter 120 is a PIG type, the first index of refraction n1 may be within a range from 1.3 to 1.7. When the wavelength converter 120 is a polycrystalline type, the first index of refraction n1 may be within a range from 1.5 to 2.0. When the wavelength converter 120 is a single-crystalline type, the first index of refraction n1 may be within a range from 1.5 to 2.0. As such, although the first index of refraction n1 may be within a range from 1.3 to 2.0, the embodiment is not limited thereto.
(56) The refractive member 140A may be formed of a material having a high second index of refraction n2. For example, the refractive member 140A may comprise at least one of Al.sub.2O.sub.3 single-crystals, and Al.sub.2O.sub.3 or SiO.sub.2 glass. As described above, the material of the refractive member 140A may be selected to have a second index of refraction n2 having a small difference n with the first index of refraction n1.
(57) In addition, when the refractive member 140A has high thermal conductivity, the refractive member 140A may advantageously radiate heat generated from the wavelength converter 120. The thermal conductivity may be changed based on the kind of material and the reference temperature (i.e. the temperature of the surrounding environment). In consideration thereof, the refractive member 140A may comprise a material having thermal conductivity within a range from 1 W/mK to 50 W/mK and/or a reference temperature within a range from 20K to 400K.
(58) As described above, the material of the refractive member 140A may be determined in consideration of the fact that light extraction efficiency and heat radiation are determined based on the kind of material of the refractive member 140A.
(59) Referring again to
(60) In addition, although the first surface S1 of the refractive member 140A (or the reflector 130A) may have a parabolic shape, the embodiment is not limited as to the shape of the first surface S1. When the first surface S1 has a parabolic shape, this may be advantageous for the collimation of light emitted through the third surface S3.
(61) In addition, the optimal position of the wavelength converter 120 on the base substrate 150A in the horizontal direction (e.g., the y-axis) may be determined based on various factors, for example, the shape of the reflector 130A.
(62) In one example, when the reflector 130A has an aspherical surface or a freeform curved surface, the first through-hole PT1 formed in the base substrate 150A may be located closer to the first surface S1 of the refractive member 140A, which faces the reflector 130A, than to the third surface S3 of the refractive member 140A, from which the light is emitted. In this case, the wavelength converter 120 is located closer to the first surface S1 than to the third surface S3. That is, the first through-hole PT1 may be spaced apart from the third surface S3 by a first distance L1, and may be spaced apart from the end of the first surface S1 by a second distance L2. This is because, in some cases, a greater amount of light may be reflected by the reflector 130A when the second distance L2 is smaller than the first distance L1. However, the embodiment is not limited thereto.
(63) In another example, when the reflector 130A has a parabolic shape, the position of the wavelength converter 120 may correspond to the focal point of the parabola. Accordingly, in this case, it is not necessary to set the second distance L2 to be smaller than the first distance L1 as described above, in order to cause a great amount of light to be reflected by the reflector 130A.
(64) The reflector 130A may include a metal layer coated over the first surface S1 of the refractive member 140A. That is, the reflector 130A may be formed by coating the first surface S1 of the refractive member 140A with a metal.
(65) The reflector 130A and the refractive member 140A may be integrated with each other. In this case, the refractive member 140A may serve not only as a lens, but also as a reflector. When the reflector 130A and the refractive member 140A are integrated with each other as described above, the light directed to the reflector 130A after passing through the wavelength converter 120 may have no possibility of coming into contact with the air.
(66) In addition, each of the refractive member 140A and the base substrate 150A may have at least one of a 2-dimensional pattern or a 3-dimensional pattern, based on the desired illuminance distribution of the light-emitting apparatus 100A.
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(68) At least one of the second portion S2-2 of the second surface S2 of the refractive member 140A or the first area A1 of the base substrate 150A may have a 3-dimensional pattern. For example, the 3-dimensional pattern on the first area A1 of the base substrate 150A may have a semispherical shape as in the embodiment B1 illustrated in
(69) In addition, the 3-dimensional pattern on the second portion S2-2 of the second surface S2 of the refractive member 140A may have a semispherical shape as in the embodiment B2 illustrated in
(70)
(71) In
(72) The 2-dimensional pattern on the second portion S2-2 of the second surface S2 of the refractive member 140A (or the upper surface of the first area A1 of the base substrate 150A) may have a circular shape as illustrated in
(73) The 2-dimensional pattern may be made to have various shapes by adjusting several variables. For example, in the case of circles or dots illustrated in
(74) In another example, the second portion S2-2 of the second surface S2 of the refractive member 140A or the upper surface of the first area A1 of the base substrate 150A may simultaneously have any one of the 3-dimensional patterns as illustrated in
(75) As described above, when the first area A1 of the base substrate 150A or the second portion S2-2 of the second surface S2 of the refractive member 140A has at least one of the 2-dimensional pattern or the 3-dimensional pattern, the scattering of light becomes active at the interface between the second surface S2 of the refractive member 140A and the first area A1 of the base substrate 150A, which may allow a greater amount of light to be reflected by the reflector 130A and then be emitted through the third surface S3. Thereby, the light extraction efficiency of the light-emitting apparatus 100A may be improved.
(76)
(77) The third surface S3 of the refractive member 140A may be a flat surface S3A as in the embodiment C1 illustrated in
(78) Alternatively, as in the embodiment C2 illustrated in
(79) Alternatively, as in the embodiment C3 illustrated in
(80) Alternatively, as in the embodiment C3 illustrated in
(81) Alternatively, as in the embodiment C4 illustrated in
(82) Alternatively, the third surface S3 may simultaneously include at least two of the various embodiments illustrated in
(83) As described above, when the third surface S3 of the refractive member 140A has various shapes, the light, reflected by the reflector 130A and introduced into the third surface S3, may be emitted in a greater amount through the third surface S3.
(84) In addition, the first reflective layer 160 may further be disposed between at least a part of the second portion S2-2 of the refractive member 140A and the first area A1 of the base substrate 150A. Although the first reflective layer 160 may take the form of a film or a coating attached to the second portion S2-2 of the refractive member 140A or the first area A1 of the base substrate 150A, the embodiment is not limited as to the manner in which the first reflective layer 160 is disposed.
(85) In the case where the first reflective layer 160 is provided, light present inside the refractive member 140A may be directed to the reflector 130A after being reflected by the first reflective layer 160. As such, a greater amount of light may be emitted through the third surface S3. That is, the light extraction efficiency of the light-emitting apparatus 100A may be improved.
(86) When the reflector 130A or the first reflective layer 160 has a reflectance below 60%, reflection cannot be properly performed. Thus, although the reflectance of the reflector 130A or the first reflective layer 160 may be within a range from 60% to 100%, the embodiment is not limited thereto. In some cases, the first reflective layer 160 may be omitted.
(87) In addition, referring again to
(88) For example, when the refractive member 140A and the wavelength converter 120 are fabricated separately, the refractive member 140A and the wavelength converter 120 may be bonded to each other via various methods.
(89) In one example, when powder such as, for example, Al.sub.2O.sub.3 or SiO.sub.2 glass, or polymer, such as silicon, is applied evenly and thinly to the bonding region of the wavelength converter 120 and the refractive member 140A, and the wavelength converter 120 and the refractive member 140A are subjected to sintering or firing, the two 120 and 140A may be bonded to each other. At this time, the first adhesive part 170 may be present between the two 120 and 140A.
(90) Alternatively, although not illustrated, a second adhesive part may be disposed between the second portion S2-2 of the second surface S2 of the refractive member 140A and the first area A1 of the base substrate 150A, so as to attach the two S2-2 and A1 to each other. In addition, the first reflective layer 160 may serve as the second adhesive part. As such, as the refractive member 140A is bonded to the base substrate 150A, rather than being directly bonded to the wavelength converter 120, the wavelength converter 120 may be indirectly bonded to the refractive member 140A.
(91) In addition, after one of the refractive member 140A and the wavelength converter 120 is first fabricated, the one that is fabricated first may be used as a substrate for the other one to be subsequently fabricated. For example, when the refractive member 140A is fabricated first, the flat surface of the refractive member 140A that is fabricate first may be used as a substrate, such that the wavelength converter 120 may be fabricated on the substrate.
(92) Alternatively, a jig may be used to fabricate the wavelength converter 120 and the refractive member 140A at the same time.
(93)
(94) Although the size of the refractive member 140A may be changed based on the performance of the entire light-emitting apparatus 100A, the size of the entire light-emitting apparatus 100A may be changed based on the size of the refractive member 140A. When it is possible to reduce the overall size of the light-emitting apparatus 100A, the freedom in the design of a headlamp for a vehicle or a flashlight including the light-emitting apparatus 100A may increase. In addition, such a reduction in size may increase portability or ease in handling.
(95) Referring to
(96)
(97) When the ratio RAT is below 0.001, the light having the wavelength converted by the wavelength converter 120 may not be used as lighting. In addition, when the ratio RAT exceeds 1, most light spreads widely to thereby be emitted from the light-emitting apparatus 100A. Thus, although the ratio RAT may be within a range from 0.001 to 1 according to the application, the embodiment is not limited thereto.
(98)
(99) For convenience of description, the light transmitting layer 180 illustrated in
(100) Each of the light-emitting apparatuses 100B, 100B-1 and 100B-2 according to the different embodiments may include the light source 110, the wavelength converter 120, a reflector 130B, 130B-1 or 130B-2, a refractive member 140B, 140B-1 or 140B-2, a substrate 150B, 150B-1 or 150B-2, first and second reflective layers 160 and 162, the first adhesive part 170, and the light transmitting layer 180.
(101) The light source 110, the wavelength converter 120, the refractive member 140B, 140B-1 or 140B-2, the first reflective layer 160, the first adhesive part 170, and the light transmitting layer 180 illustrated in
(102) Accordingly, of course, the difference in the index of refraction between the wavelength converter 120 and the refractive member 140B, 140B-1 or 140B-2, the shape of the second portion S2-2 of the second surface S2 of the refractive member 140A or the 3-dimensional pattern and the 2-dimensional pattern on the first area A1 of the base substrate 150A illustrated in
(103) However, in the case of the light-emitting apparatus 100A illustrated in
(104) In addition, the light source 110 may be spaced apart from the reflector 130B, 130B-1 or 130B-2 by the second distance d2. Here, although the second distance d2 may be 10 m or more, the embodiment is not limited thereto.
(105) Meanwhile, unlike the reflector 130A of the light-emitting apparatus 100A illustrated in
(106) Like the first through-hole PT1, although laser diodes having a narrower viewing angle than light-emitting diodes may be advantageous in order to introduce light into the second through-hole PT2, the embodiment is not limited thereto. That is, when an optical system (not illustrated) capable of reducing the viewing angle is located between the light source 110, i.e. the light-emitting diodes and the second through-hole PT2, it is possible to reduce the viewing angle of light emitted from the light-emitting diodes to enable the easy introduction of light into the second through-hole PT2.
(107) In addition, the base substrate 150A of the light-emitting apparatus 100A illustrated in
(108) The recess 152 is formed in the second area A2 of the base substrate 150B-1, and the wavelength converter 120 is located in the recess 152.
(109) In addition, the second reflective layer 162 may be disposed in the recess 152 between the wavelength converter 120 and the base substrate 150B-1. The light, which is introduced into the wavelength converter 120 by way of the refractive member 140B-1 through the second through-hole PT2, may pass through the wavelength converter 120 so as to be absorbed by the base substrate 150B-1, or may be emitted through the bottom surface of the base substrate 150B-1. To prevent this, the second reflective layer 162 is disposed. The second reflective layer 162 reflects the light having passed through the wavelength converter 120 so as to direct the light to the refractive member 140B-1. Thereby, the light extraction efficiency of the light-emitting apparatus 100B or 100B-1 may be improved. The second reflective layer 162 may take the form of a film, or a coating attached to the wavelength converter 120 or the base substrate 150B-1.
(110) When the reflectance of the second reflective layer 162 is below 60%, the second reflective layer 162 cannot properly perform reflection. Thus, although the reflectance of the second reflective layer 162 may be within a range from 60% to 100%, the embodiment is not limited thereto.
(111) In some cases, the second reflective layer 162 may be omitted.
(112) Meanwhile, referring to
(113) Referring to
(114) In the case where the light, the wavelength of which is not converted in the wavelength converter 120, is reflected by the reflector 130B-1 or 130B-2 to thereby be output, assuming that the numerical value of the Maximum Permissible Exposure (MPE) of the output light is 0.00255 W/m.sup.2 or less and the exposure time of the light to the human body is 0.25 seconds or less, the light has no harmful effect on the human body. Here, MPE means the maximum intensity of laser beam output that does not cause any damage to the human, body.
(115) However, when the numerical value of the MPE is greater than 0.00255 W/m.sup.2 and the exposure time becomes greater than 0.25 seconds, the light may cause biological damage to the human body including the eyes and the skin. Therefore, to prevent this problem, it is necessary to return the light, the wavelength of which is not converted in the wavelength converter 120, to the light source 110 through the second through-hole PT2 in the direction designated by the arrow LP3 after the light travels in the direction designated by the arrow LP2 through the inner surface of the refractive member 140B-1 or 140B-2.
(116) That is, the light, the wavelength of which is not converted in the wavelength converter 120, needs to travel in the direction designated by the arrow LP2, which is parallel to the second normal NL2 of the wavelength converter 120, within the refractive member 140B-1 or 140B-2. In addition, the light, which is introduced through the second through-hole PT2 and refracted in the refractive member 140B-1 or 140B-2 so as to be directed to the wavelength converter 120, needs to travel in the direction parallel to the second normal NL2 of the wavelength converter 120. To this end, at least one of the incident angle 1 of the light into the second through-hole PT2, illustrated in
(117) Here, the incident angle 1 means the angle between the traveling path of the light emitted from the light source 110 and the first normal NL1 at the point of the reflector 130B-1 or 130B-2 where the second through-hole PT2 is present.
(118) When the difference between the first distance CV1 or CV3 and the second distance CV2 or CV4 is not great, it may not be necessary to adjust the incident angle 1 or the rotation angle 2.
(119) When the difference between the first distance CV1 or CV3 and the second distance CV2 or CV4 increases, it may be possible to cause the light to travel in a direction parallel to the second normal NL2 in the refractive member 140B-1 or 140B-2 by adjusting only one of the incident angle 1 or the rotation angle 2.
(120) When the difference between the first distance CV1 or CV3 and the second distance CV2 or CV4 increases further, it may be possible to cause the light to travel in a direction parallel to the second normal NL2 in the refractive member 140B-1 or 140B-2 by adjusting both the incident angle 1 and the rotation angle 2.
(121) As described above, according to the position of the reflector 130B, 130B-1 or 130B-2 at which the second through-hole PT2 is formed, i.e. according to the position of the reflector 130B, 130B-1 or 130B-2 into which the light is introduced, at least one of the incident angle 1 or the rotation angle 2 may be adjusted.
(122)
(123) The light-emitting apparatus 100C of the present embodiment may include the light source 110, the wavelength converter 120, a reflector 130C, a refractive member 140C, a substrate 150C, and the light transmitting layer 180.
(124) The light source 110, the wavelength converter 120, the reflector 130C, the refractive member 140C, the substrate 150C, and the light transmitting layer 180 illustrated in
(125) The relative arrangement of the reflector 130C, the refractive member 140C, and the substrate 150C differs from that in the light-emitting apparatus 100A, illustrated in
(126) In the case of the light-emitting apparatuses 100A, 100B 100B-1 and 100B-2 illustrated in
(127) In addition, unlike the refractive members 140A, 140B-1 and 140B-2 illustrated in
(128) In addition, the first surface S1 of the refractive member 140C has a cross-sectional shape including first and second portions S1-1 and S1-2 which are located on the left and right sides of the second surface S2 and face the reflector 130C. For example, the first and second portions S1-1 and S1-2 of the first surface S1 may have bilaterally symmetrical cross-sectional shapes with the second surface S2 as the center.
(129) In addition, unlike the light-emitting apparatus 100A illustrated in
(130) In addition, the first surface S1 and the second surface S2 of the refractive member 140C may have a parabolic shape.
(131) The reflector 130C is formed with a third through-hole PT3 in the same manner as the light-emitting apparatuses 100B, 100B-1 and 100B-2 illustrated in
(132) Hence, the description of the light-emitting apparatuses 100A, 100B, 100B-1 and 100B-2 illustrated in
(133) Although not illustrated in
(134) In addition, the above description related to the difference in the index of refraction between the wavelength converter 120 and the refractive member 140A may be applied to the difference in the index of refraction between the wavelength converter 120 and the refractive member 140C. In addition, the shape of the pattern on the second-second portion S2-2 of the second surface S2 of the refractive member 140A or the shape of the pattern on the first area A1 of the base substrate 150A illustrated in
(135) When the light-emitting apparatuses 100A to 100C described above are used for a lighting apparatus for a vehicle, a plurality of light sources 110 may be provided. As such, the number of light sources 110 that is provided may be changed according to the applications of the light-emitting apparatuses 100A to 100C of the embodiments.
(136) Hereinafter, light-emitting apparatuses 100D to 100G according to other embodiments, which include the light sources 110 and various optical devices, will be described with reference to the accompanying drawings. For convenience of description, although three light sources 110 will be described, two light sources 110 may be provided, or four or more light sources 110 may be provided.
(137)
(138) The light-emitting apparatuses 100D and 100E illustrated in
(139) In addition, the light-emitting apparatuses 100D and 100E illustrated in
(140) In addition, the light-emitting apparatuses 100F and 100G illustrated in
(141) Each of the light-emitting apparatuses 100D and 100E illustrated in
(142) In
(143) Although the radiator 114 may be attached to the rear surface of the circuit board 112A or 112B so as to outwardly discharge heat generated in the light-emitting apparatus 100A or 100B-1, the embodiment is not limited as to the position of the radiator 114. In another embodiment, the radiator 114 may be attached to the rear surface of the base substrate 150A or 150B-1, in addition to the circuit board 112A or 112B. In still another embodiment, the radiator 114 may be attached only to the rear surface of the base substrate 150A or 150B-1 without being attached to the rear surface of the circuit board 112A or 112B. Alternatively, in some cases, the radiator 114 may be omitted, the radiator 114 may be located on the side surface as well as the rear surface of the circuit board 112A or 112B or the base substrate 150A or 150B-1, or the radiator 114 may be located only on the side surface and not on the rear surface of the circuit board 112A or 112B or the base substrate 150A or 150B-1.
(144) Although the radiator 114 may be formed of aluminum, the radiator 114 may be embodied as, for example, a Thermal Electric Cooler (TEC) in order to achieve higher radiation efficiency. However, the embodiment is not limited as to the position or the constituent material of the radiator 114.
(145) In addition, at least one first lens 116 and/or 118 may focus the light emitted from the light sources 110 so as to emit the light through the first or second through-hole PT1 or PT2.
(146) For example, at least one first lens may include the first-first lens 116 and the first-second lens 118. The first-second lens 118 may include three lenses 118-1, 118-2 and 118-3 which are located respectively between the respective light sources 110-1, 110-2 and 110-3 and the first-first lens 116. That is, the first-second lenses 118 may be provided in the same number as the number, of the light sources 110. The first-second lenses 118; 118-1, 118-2 and 118-3 serve to focus or collimate the light emitted from the light sources 110; 110-1, 110-2 and 110-3. Thus, when the light-emitting apparatus according to any one of the embodiments is applied to a headlight for a vehicle or a flashlight, light may reach very far in a straight line. According to the application, the first-second lenses 118; 118-1, 118-2 and 118-3 may be omitted. That is, when the light emitting device is applied to a traffic light, in order to allow the light emitted from the light-emitting apparatus to spread rather than traveling straight, the first-second lenses 118; 118-1, 118-2 and 118-3 may be omitted.
(147) The first-first lens 116 is located between the first-second lens 118 and the first or second through-hole PT1 or PT2. When the first-second lens 118 is omitted, the first-first lens 116 may be located between the light sources 110; 110-1, 110-2 and 110-3 and the first or second through-hole PT1 or PT2. The first-first lens 116 may be a f lens. In the case of a general lens, when the position of a light source is changed, the position on which the light that is generated from the light source and passes through a lens is focused is changed. However, in the case of the f lens, even if the position of the light source is changed, the position on which the light having passed through the lens is focused is not changed. Accordingly, the first-first lens 116 may collect the light emitted from the light sources 110-1, 110-2 and 110-3 and transmit the collected light to the first mirror 196.
(148) The first mirror 196 is located between the first-first lens 116 and the first or second through-hole PT1 or PT2 and serves to reflect the light focused by the first-first lens 116 so as to introduce the light to the first or second through-hole PT1 or PT2.
(149) Meanwhile, the surface of the circuit board 112A or 112B, on which the light sources 110; 110-1, 110-2 and 110-3 are mounted, may be a curved surface or a spherical surface as illustrated in
(150) Various methods may be used in order to collect the light from the light sources 110. For example, as illustrated in
(151) However, when the surface of the circuit board 112B, on which the light sources 110; 110-1, 110-2 and 110-3 are mounted, is a flat surface illustrated in
(152) In addition, optical fibers may be used to collect the light from the light sources 110 together so as to introduce the collected light into the first or second through-hole PT1 or PT2.
(153) Meanwhile, the light-emitting apparatuses according to the above-described embodiments may be applied to various fields. For example, the light-emitting apparatus may be applied in a wide variety of fields such as various lamps for vehicles (e.g. a low beam, a high beam, a tail lamp, a sidelight, a turn signal, a Day Running Light (DRL), and a fog lamp), a flash light, a traffic light, or various other lightings.
(154)
(155) The light-emitting apparatus 100H illustrated in
(156) The second lens 198 may be disposed to face the third surface S3 of the refractive member 140B-1 or 140C. The support part 230 is the part which may be coupled to at least one of the light source 110, the reflector 130B-1 or 130C, the refractive member 140B-1 or 140C, the base substrate 150B-1 or 150C, the circuit board 112A or 112B, the radiator 114, or the second lens 198 so as to support the same.
(157) After the components corresponding to the light-emitting apparatus 100H or 100I are primarily supported by the support part 230 as illustrated in
(158) The light-emitting apparatuses 100H and 100I illustrated in
(159) In addition, the second lens 198 illustrated in
(160) In conclusion, the light-emitting apparatuses 100A to 100I according to the above-described embodiments convert the wavelength of light excited by the light source 110 using the wavelength converter 120 so as to have a desired color and color temperature, and thereafter direct the light to the reflector 130A to 130C through the refractive member 140A to 140C without passing through an air layer.
(161) Generally, light may undergo total internal reflection due to the difference in the index of refraction between materials when the light travels from a material having a high index of refraction to a material having a low index of refraction. When the difference in the index of refraction between the materials is great, the probability of total internal reflection increases, thereby reducing the efficiency with which the light is extracted outward. In consideration of this, in the case of the light-emitting apparatuses 100A to 100I according to the embodiments, the light, reflected by or transmitted through the wavelength converter 120, is directed to travel to the reflector 130A to 130C through the refractive member 140A to 140C instead of the air layer, and in turn the light reflected by the reflector 130A to 130C is emitted to the air through the third surface S3 of the refractive member 140A to 140C without passing through the air layer. That is, in the case of the light-emitting apparatuses 100A to 100I according to the embodiments, no air layer is present between the refractive member 140A to 140C and the reflector 130A to 130C, and no air layer is present between the refractive member 140A to 140B-2 and the base substrate 150A to 150B-2. As such, the light extraction efficiency may be enhanced, and the distribution of light to be emitted, i.e. the illuminance distribution may be adjusted in a desired manner.
(162)
(163) Referring to
(164) In addition, when the reflector 130A to 130C is integrated with the refractive member 140A to 140C, the size of the entire light-emitting apparatus 100A to 100I may be reduced. Through a reduction in the size of the light-emitting apparatus 100A to 100I, the freedom in design may be increased when the light-emitting apparatus 100A to 100I is applied to lighting for a vehicle or a general lamp such as a flash light. In addition, the reduced size of the light-emitting apparatus 100A to 100I may ensure portability and ease in handling.
(165) In addition, as the refractive member 140A to 140C is formed of a material having high thermal conductivity, the refractive member may realize the efficient radiation of heat generated from the wavelength converter 120, thereby achieving excellent radiation effects.
(166) In addition, as exemplarily illustrated in
(167) Hereinafter, although a method for fabricating the above-described refractive member 140A, 140B-1 or 140B-2 will be described with reference to the accompanying drawings, the refractive member 140A, 140B-1 or 140B-2 may be fabricated via various other methods.
(168)
(169) First, a refractive material 140 is prepared as exemplarily illustrated in
(170) Subsequently, as exemplarily illustrated in
(171) As is apparent from the above description, light-emitting apparatuses according to the embodiments may achieve excellent light extraction efficiency, may adjust the distribution of light to be emitted, i.e. the illuminance distribution in a desired manner, may increase the freedom in design when applied to lighting, for a vehicle or a general lamp such as a flash light owing to a reduction in the entire size thereof, may ensure portability and ease in handling owing to the reduced size, and may exhibit excellent heat radiation effects.
(172) Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.