JP6706448B2 - LED device using neodymium/fluorine material - Google Patents

Description

The present invention relates generally to lighting applications and related arts, and more specifically, but not exclusively, the present invention uses compounds containing neodymium and fluorine to provide desired color filtering effects in LED lighting devices. Regarding what to do.

Light emitting diodes (LEDs) (also referred to herein as organic LEDs (OLEDs)) are solid state semiconductor devices that convert electrical energy into electromagnetic radiation containing visible light (wavelength: about 400-750 nm). LEDs generally include a chip (die) of semiconductor material that has been doped to form a pn junction. The LED chip is electrically connected to the anode and the cathode, and in many cases, the anode and the cathode are both mounted inside the LED package. The visible light emitted by the LED has a high directivity and a narrow beam width as compared with other lamps such as an incandescent lamp and a fluorescent lamp.

OLEDs generally include one or more electroluminescent light-emitting layers (organic semiconductor films) provided between electrodes (one or more electrodes being transparent). The electroluminescent light emitting layer emits light in response to a current flowing between the electrodes.

LED/OLED light sources (lamps) offer a variety of advantages over conventional incandescent and fluorescent bulbs. Examples of such advantages include longer life expectancy, higher energy efficiency, no stabilization time required to reach final brightness, etc. However, it is not limited to these.

Although LED/OLED lighting is attractive for efficiency, long life, flexibility and other desirable aspects, the color characteristics of LED lighting (especially in white LED/OLED devices) for use in both general lighting and display applications. There is still a need for continuous improvement.

FIG. 1 is a perspective view of a conventional LED-based lighting device 10 suitable for area lighting applications. A lighting device (also referred to as “lighting unit” or “lamp”) 10 includes a transparent or translucent cover or envelope 12, a screw-type base 14, a housing between the envelope 12 and the base 14, or And a base portion 16.

The LED light source (not shown) may be an LED array including a plurality of LED devices, and the LED array may be provided on the lower end of the envelope 12 and the adjacent base 16. Since LED devices emit visible light in a narrow band of wavelengths (eg, green, blue, red, etc.), various LED devices can be used in LED lamps to generate various colors of light, including white light. Often used in combination. Alternatively, the light that looks substantially white is a phosphor that converts at least part of the blue light from the blue LED into a different color (for example, yttrium aluminum garnet:cerium, YAG:Ce is abbreviated). Can be generated by combining with light from. Combining the converted light with blue light can produce light that appears white or substantially white. The LED device can be mounted on a mount inside the base 16 and can be encapsulated on the mount by a protective cover. To increase the efficiency of visible light extraction from the LED device, the protective cover includes a refractive index matching material.

To enhance the ability of the lighting device 10 to emit visible light in almost all directions, the envelope 12 shown in FIG. 1 may be substantially spheroidal or elliptical. To further enhance the ability to illuminate in substantially all directions, the envelope 12 may include a material that allows the envelope 12 to function as a diffuser. The material used to make the diffuser may include polyamide (eg, nylon), polycarbonate (PC), polypropylene (PP), or the like. These polymeric materials may include SiO ₂ to enhance the refraction of light and thereby give a reflective white appearance. A film (not shown) containing the phosphor composition may be provided on the inner surface of the envelope 12.

By using a combination of different LED devices and/or phosphors, the ability of LED lamps to produce a white light effect can be increased. However, as an alternative or as an additional method, other approaches to improve the color characteristics of the white light produced by the LED device are desirable.

U.S. Patent Application Publication No. 2014/268,794

In one aspect of the invention, a device comprises one or more light emitting diode (LED) modules configured to generate visible light, and one or more light emitting diodes (LEDs) comprising a compound comprising elemental neodymium (Nd) and elemental fluorine (F). And one or more components configured to provide a desired light spectrum by filtering the generated visible light with a compound.

In addition to aspects of the invention, the compound may include Nd ³⁺ ions and F ⁻ ions .

Furthermore, in an aspect of the invention, one or more LED modules may include organic LEDs.

Further in one aspect of the invention, the one or more components may be a sealing layer deposited on top of the one or more LED modules. Additionally, the encapsulation layer may include glass (eg, low temperature glass), polymers, polymer precursors, thermoplastic or thermosetting polymers or resins, epoxies, silicones, or silicone epoxy resins. Additionally, one or more components may further include a phosphor.

Further in an aspect of the invention, the one or more components may be an encapsulation layer, the encapsulation layer being deposited on a further encapsulation layer comprising a phosphor, the additional encapsulation layer being one or more It is deposited on the LED.

Further, in an aspect of this invention, the compounds may include one or more of Nd.F compounds and Nd.X.F compounds. In the formula, X is one or more of the elements O, N, S, Cl, OH, Na, K, Al, Mg, Li, Ca, Sr, Ba and Y. Further, the compound may be one or more of NdF ₃ and NdFO.

Further in one aspect of the invention, the one or more components may be optical elements. The optical element includes a transparent, semi-transparent or reflective base material having a surface coated with a film. The coating contains a compound containing Nd and F to provide the desired light spectrum by filtering the generated visible light. Further, the weight percentage of compound in the coating may be from about 1% to about 20% and the thickness of the coating may be from about 50 nm to about 1000 μm. Further, the film may further include an additive having a refractive index higher than that of the above compound, and the additive is selected from a metal oxide and a non-metal oxide (wherein the additive is TiO ₂ , SiO ₂₎ . ₂ and Al ₂ O ₃ ). Further, the coating may coat the inner surface of the substrate. Further, the substrate may be a diffuser selected from the group consisting of a light bulb, a lens and a dome enclosing one or more LED modules. Further, the optical element may further include a bonding layer between the base material and the film. The bonding layer includes an organic adhesive or an inorganic adhesive.

Further, in an aspect of the present invention, the coating may be applied to the surface of the substrate by either a spray coating method or an electrostatic coating method.

Further, in aspects of the present invention, the compound may include discrete particles of organic or inorganic materials. The particle size of the organic or inorganic material is from about 1 nm to about 10 μm.

Further in an aspect of the invention, a device may comprise a circuit (eg, an integrated circuit) and a plurality of LED modules having at least one of the components (eg, a corresponding plurality of components).

These and other features and aspects of the present disclosure will be better understood upon a reading of the following detailed description with reference to the accompanying drawings. In the figures, the same reference numbers represent similar parts.

It is a perspective view of the conventional LED lighting apparatus. 3 is a graph comparing the absorption in the visible spectrum of neodymium fluoride dispersed in silicone with that of standard neodymium glass. 6 is a graph comparing the emission spectrum of a device in which NdF ₃ is added into silicone and directly deposited on a commercially available LED package (Nichia 757) and the base Nichia 757 LED. 6 is a graph comparing the emission spectrum of a device in which NdF ₃ is added to silicone and directly deposited on a chip-on-board (COB) array (TG66) and the base TG66 COB array. A graph comparing the emission spectrum of an element directly deposited on a commercially available LED package (Nichia 757 with a CCT of 4000K with Nd·F·O added to silicone) and the base Nichia 757 LED. Is. Various of the present invention with the addition of Nd.F compounds (or more generally Nd.X.F compounds as described herein) with the phosphor to obtain preferred visible light absorption/generation properties. It is a figure which shows the non-limiting example of the LED lighting apparatus which concerns on embodiment. It is sectional drawing of the LED illuminating device which concerns on one Embodiment of this invention. It is sectional drawing of the LED illuminating device which concerns on another embodiment of this invention. It is a perspective view of the LED illuminating device which concerns on another embodiment of this invention. It is a perspective view of the LED illuminating device which concerns on another embodiment of this invention.

Novel devices such as lighting devices are presented herein. The device contains one or more LED (or OLED) modules configured to generate visible light, such as white light, and the elements neodymium (Nd) and fluorine (F), and one or more other One or more constituent elements (for example, an optical element) containing a compound containing an element appropriately. The illuminator is configured to provide a desired light spectrum by filtering the generated visible light with a compound. This is as described in this specification. Generally, the compound comprises Nd ³⁺ ions and F ⁻ ions . In the present invention, “Nd·F compound” should be broadly construed as including a compound containing neodymium and a fluoride, and optionally other elements.

According to one embodiment, the components, LED (OLED) may comprise a composite material / sealing layer on the surface of the chip, as disclosed in Nd · F compounds such as NdF ₃ and / or described herein Other materials can be mixed (diffused) into the encapsulation layer (eg, with the phosphor), thereby achieving the desired visible light absorption profile. The composite/sealing layer may be formed using low temperature glass, polymers, polymer precursors, silicone or silicone epoxy resins or precursors, and the like.

According to another embodiment, the optical element may be a transparent, translucent, reflective, or transflective (partially reflective and transmissive) substrate. While the visible light produced by the LED module passes through this optical element, the coating provided on the surface of the substrate can exert a color filtering effect on the visible light, such as the wavelength of yellow light. Visible light in the region may be filtered for wavelengths of, for example, about 560 nm to about 600 nm.

Further, the transparent or translucent base material of the optical element may be a diffuser such as a light bulb, a lens, and an enclosure for enclosing one or more LED chips. Further, the substrate may be a reflective substrate, sometimes the LED chip may be located outside the substrate. A coating of Nd.F and/or Nd.X.F compound may be disposed on the surface of the substrate, the thickness of the coating being sufficient to achieve a color filtering effect. The thickness may generally be from about 50 nm to 1000 μm, and the preferred thickness may be 100 nm to 500 μm.

The resulting device can exhibit improved optical parameters using Nd·F compound/material filtering. The compound/material has an intrinsic absorption in the visible region of about 530 nm to 600 nm, whereby CSI (color saturation index), CRI (color rendering index), R9 (color rendering value for a particular color chip) , "Revealness" (a color rendering index that those skilled in the art understand to refer to LPI (Lighting Preference Index)) and the like. R9 is defined as one of the six saturated test colors not used in the CRI calculation. "Revealability" is a parameter of emitted light based on one form of LPI. This is described in co-pending, co-owned international application PCT/US2014/054868 (published as WO2015/035425 on March 12, 2015), filed on September 9, 2014. ing. That patent application is incorporated herein by reference.

In one embodiment, an NdF material with a relatively low index of refraction (RI) (eg, NdF _{3 with} an index of around 1.6) is used to encapsulate to reduce scattering losses in LED packages and COB arrays. It is convenient to match the index of refraction of the stop material. Further, the absorption spectrum is finely adjusted by including an electronegative “X” atom (where X can be, for example, O, N, S, or Cl) in the Nd·X·F material. Therefore, it would be more convenient if the absorption width around 580 nm could be widened and the color rendering of the R9 color chip could be improved. Any of these may be mixed with the encapsulant for color adjustment. The selection of the appropriate Nd.F or Nd.X.F material (detailed below) should be such that scattering losses due to refractive index mismatch are minimized. The use of Nd·F compounds may also be advantageous for use in LED lighting applications involving short UV wavelengths. This is because Nd·F compounds are generally not activated in the wavelength range of about 380 to 450 nm.

According to another embodiment, the Nd·F compound is neodymium fluoride (NdF ₃ ), or neodymium oxyfluoride (eg NdO _x F _y (where 2x+y=3), eg Nd ₄ O ₃ F ₆ ), Or neodymium fluoride containing exogenous water and/or oxygen, or neodymium fluoride hydroxide (eg Nd(OH) _a F _b , where a+b=3), or many others containing neodymium and fluoride Which are easily clarified from the following description. In some applications, the Nd·F compound may have a relatively low index of refraction (eg, an index of refraction that matches the selected polymeric material) to provide a low loss mixture. One such Nd · F materials are thought to neodymium fluoride (NdF _3). Its index of refraction is around 1.6, providing a low index suitable for index matching with certain polymer matrix materials in minimizing scattering losses.

According to yet another embodiment, other NdF compounds/materials can be used to provide the benefits described herein. For example, non-limiting examples of other compounds containing Nd.F may include Nd.X.F compounds. In addition to the explanation that X can be O, N, S, Cl or the like, X can be at least one metal element (other than Nd) that can form a compound with fluorine. Examples include: metal elements such as Na, K, Al, Mg, Li, Ca, Sr, Ba, or Y, or combinations of such elements. For example, Nd · X · F compounds may contain NANDF _4. Further examples of the Nd.X.F compound include compounds in which X is Mg and Ca, or Mg, Ca and O, and other compounds containing Nd.F (including a neodymium-doped perovskite structure). Can be mentioned. Some Nd.X.F compounds may advantageously allow wider absorption at wavelengths of about 580 nm. The neodymium oxyfluoride compound may contain varying amounts of O and F, which means that the neodymium oxyfluoride compound is generally derived from varying amounts of neodymium oxide (neodymia) Nd ₂ O ₃ and neodymium fluoride NdF _3. Therefore, the neodymium oxyfluoride compound was selected between the refractive index of the Nd·O compound (for example, 1.8 for neodymia) and the refractive index of the Nd·F compound (for example, 1.60 for NdF ₃ ). It may have a refractive index. Non-limiting examples of neodymium-doped perovskite structure materials include at least one component (eg, Na, K, Al, Mg, Li, Ca) having a lower refractive index than a neodymium compound (eg, NdF ₃ ). And those containing Sr, Ba, and Y metal fluorides). Such a "host" compound may have a lower refractive index than the NdF ₃ in the visible light spectrum. As non-limiting examples thereof, NaF (n=1.32), KF (n=1.36), AlF ₃ (n=1.36), MgF ₂ (n=1.38) at a wavelength of 589 nm, Examples include LiF (n=1.39), CaF ₂ (n=1.44), SrF ₂ (n=1.44), BaF ₂ (n=1.48) and YF ₃ (n=1.50). Can be done. As a result of doping with a high-refractive-index Nd·F compound (for example, NdF ₃ ), the refractive index of the perovskite structure compound obtained by doping is changed from that of the host (for example, 1.38 of MgF ₂ ) to that of NdF ₃ . It can be a value between the refractive index (1.60). The refractive index of a metal fluoride compound doped with NdF ₃ will depend on the ratio of Nd ions to metal ions.

The refractive index of NdF ₃ is about 1.60. Therefore, NdF ₃ gives relatively good refractive index matching may be considered sometimes when implementing a mixture of silicone (1.51 may have a refractive index of around). Even better index matching can be obtained by mixing NdF ₃ with another material. The material may or may not contain Nd. For example, the refractive index of NaNdF ₄ is around 1.46. Therefore, by properly mixing NdF ₃ with another material (eg, NaF or NaNdF ₄ ), the refractive index of the mixture can be better matched to that of silicone.

FIG. 2 shows the absorption in the visible spectrum of neodymium fluoride dispersed in silicone (curve 22) and standard neodymium glass (eg Na ₂ O.Nd ₂ O ₃ .CaO.MgO.Al as the composition of Nd glass). ₂ O ₃ · K ₂ using _{O · B 2 O 3 · SiO} 2) that of the (curve 20), which is a graph comparing as a function of wavelength. It is important that each material share many of the same absorption characteristics, especially in the yellow region (eg, about 570 nm to about 590 nm). In practical use, the LED chip/die can be sealed with a sealing material (eg, silicone, epoxy, acrylic resin, etc.). The encapsulant is a Nd.F or Nd.F.O-based material (eg, in a silicone deposited directly on an LED chip or an array of LED chips (eg, chip-on-board array, COB array). NdF ₃ ) may be contained. This is described in more detail herein.

FIG. 3 is a graph comparing the emission spectra (curve 32) of a device with NdF ₃ added in silicone and deposited directly on a commercial LED package (Nichia 757) (ie, the LED package was further encapsulated). Is. As can be seen in FIG. 3, there are considerable differences in the spectra. Specifically, as compared with the emission spectrum of the Nichia 757 LED (curve 30), which is the base, one or more regions in which the region largely falls in the range of about 570 nm to about 590 nm are seen.

FIG. 4 shows the emission spectrum of a device (curve 42) directly deposited on a COB array (TG66) with NdF ₃ added in silicone and that of the base TG66 COB array (curve 40) as a function of wavelength. Is a graph to be compared with. The spectrum of curve 42 is similar to curve 32 of FIG.

Example, Nd · F material (e.g., NdF ₃₎ when used in the LED package or array as part of the sealing material, color filtering extinction in enhancing at least one of lighting an indicator which in turn It has proven useful as a material: CSI, CRI, R9, or whiteness (ie closeness to the white body radiation locus) etc. Table 1 below shows the performance obtained for the examples given in FIGS. 3 and 4 compared to a conventional LED containing Nd glass.

Table 1. Comparison of Performance Results Shown in FIGS. 3 and 4 with Conventional LEDs with Nd Glass As can be seen from Table 1 above, the Nichia 757 LED device generally has a lumen/watt value of 236. When NdF ₃ is used as the encapsulant in silicone, CRI (color rendering/saturation index) is 92, R9 (color rendering value of red chip) is 60, color gamut index (GAI) is 49, The LPI-based visibility (as defined in the present invention) is 110. When sealing the LED chip TG66 array (COB array) to the silicone in NdF ₃ containing, CRI is 90, R9 value 39, GAI 50, "manifestation degree" is also 110. These values are preferable to the color filtering effect when the white LED is combined with Nd glass shown in the bottom row of Table 1. Values of chromaticity coordinates (CCX and CCY) and CCT (correlated color temperature) are shown for reference in all three cases.

Nd · F material need not be simply neodymium fluoride as shown in the example of FIG. 3 and FIG. 4 (NdF _3). The Nd.F material may be any Nd.X.F compound (where X represents the other element or combination of elements described above and is chemically bound to F). As such, such Nd.X.F materials may enhance at least one of the following lighting indicators: CSI, CRI, R9, whiteness (ie, proximity to white body radiation locus), etc.

For example, FIG. 5 shows the emission spectrum (curve of a device in which Nd·F·O is added to silicone and directly deposited on a commercially available LED package (Nichia 757 with a CCT of 4000K) to further seal the LED package. 52) is a graph comparing 52) as a function of wavelength. Similar to the examples of FIGS. 3 and 4, in comparison with the emission spectrum of the base Nichia 757 LED (curve 50), in the spectrum 52, one or more regions in which there is a large drop in the section between about 570 nm and about 590 nm are seen Be done.

Table 2 below shows devices obtained by directly depositing the performance obtained for the example given in FIG. 5 on a commercially available LED package (Nichia 757 with a CCT of 4000K) by adding Nd·F·O to silicone. Is shown. For conventional LEDs with silicone encapsulant (Nichia 757 with a CCT of 4000K) and devices with other types of silicone encapsulant doped with neodymia (Nd ₂ O ₃ ) and neodymium fluoride (NdF ₃ ). , Shown for comparison. In addition to the same parameters as in Table 1, Table 2 also shows CSI (Saturation Index) parameters for the materials.

Table 2. Comparison of performance results of LEDs with silicone encapsulants doped with various Nd-based materials and unencapsulated silicone encapsulants Nd ₂ O ₃ has a higher refractive index than others, so the scattering loss is either NdFO or NdF ₃ . It is noted that it will be larger than either. However, NdFO is superior in terms of balance between CSI and LPI. NdF Nd · F compound such as _3, whether a mixture of NdFO material it alone, a low refractive index as compared with Nd ₂ O _3, scattering loss is minimized. Furthermore, Nd · F compound such as NdF _3, whether a mixture of NdFO material it alone, as compared to Nd ₂ O _3, can be realized a yellow absorption peak desired for the spectrum of the LED light, the number (lumens The CSI value improves (although it has the drawback of decreasing). Chromaticity coordinates (CCX and CCY), CCT and CRI values are also shown for all four cases.

In some embodiments, Nd.F or Nd.F.O or Nd.X.F materials may be selected to match the index of refraction with the encapsulation material to minimize scattering losses. Also, one Nd.F material (eg, neodymium fluoride) can be mixed with another Nd.X.F material (eg, neodymium oxyfluoride). The element "X" in the Nd.X.F compound can be selected to fine tune the absorption in the region around 580 nm in order to better match the spectrum to the "R9 curve."

In some embodiments, the Nd.F material (which broadly includes all Nd.X.F materials described herein) is combined with one or more luminescent materials (eg, phosphors) as an encapsulating material. Can be mixed. For example, the NdF color filtering material can be mixed with a yellow-green phosphor and/or a red phosphor. For example, the NdF material may be mixed with Ce-doped YAG phosphors and/or conventional red nitride phosphors (eg, Eu ²⁺ -doped CaAlSiN red phosphors). In another example, the Nd.F.O material can be mixed with silicone along with YAG:Ce phosphor and red nitride phosphor and used to encapsulate Nichia 757 blue emitting LEDs. Without being limited to theory, the emission from the YAG:Ce phosphor and the red nitride phosphor can be improved by the addition of Nd·F·O according to the Mie scattering theory.

FIGS. 6a-6d show Nd.F compounds (or more generally Nd.X.F compounds as described herein) with phosphors to achieve favorable visible light absorption/generation properties. Figure 6 shows non-limiting examples of different LED lighting devices 60a, 60b, 60c and 60d, each added according to various embodiments of the present invention. In FIGS. 6 a to 6 d, the LED lighting device 60 a, 60 b, 60 c, or 60 d includes a dome 62. The dome 62 can be an optically transparent or translucent substrate that encapsulates the LED chip 65 mounted on a printed circuit board (PCB) 66. The lead wires supply a current to the LED chip 65, which causes it to emit light. The LED chip may be any semiconductor light source, in particular a blue or UV light source capable of producing white light when the emitted radiation strikes the phosphor. In particular, the semiconductor light source has an emission wavelength of greater than about 200 nm and less than about 550 nm and is of the form In _i Ga _j Al _k N, where 0≦i, 0≦j, 0≦k, and i+j+k=1. A blue/ultraviolet emitting LED based on a nitride compound semiconductor generalized in 1. More specifically, the LED chip may be a near UV or blue emitting LED having a peak emission wavelength of about 400 to about 500 nm. Even more specifically, the LED chip may be a blue emitting LED having a peak emission wavelength in the range of about 440 to 460 nm. Such LED semiconductors are known in the art.

According to one embodiment shown in FIG. 6a, a polymer composite (encapsulant compound) layer 64a is mixed with a phosphor to provide desirable visible light absorption and generation properties, various implementations described herein. It may include a Nd.F compound according to the form (and/or generally an Nd.X.F compound). The compound layer 64a can be disposed directly on the surface of the LED chip 65 and can be radiatively coupled to the LED chip. By "radiatively coupled" is meant that the radiation from the LED chip is transmitted to the phosphor and the phosphor emits radiation of a different wavelength. In certain embodiments, the LED chip 65 may be a blue LED and the polymer composite layer is a mixture of Nd.F and a yellow-green phosphor (eg, cerium-doped yttrium aluminum garnet, Ce:YAG). Can be included. The blue light emitted by the LED chip mixes with the yellow-green light emitted by the phosphor of the polymer composite layer and is further filtered by NdF so that the net emission appears as white light. Thus, the LED chip 65 can be encapsulated by the encapsulant layer 64a. The encapsulating material may be low temperature glass, a thermoplastic or thermosetting polymer or resin, or a silicone or epoxy resin. The LED chip 65 and the encapsulant layer 64a can be encapsulated inside a shell (limited by the dome 62). Alternatively, the LED lighting device 60a may include only the encapsulant layer 64a and not the outer shell/dome 62. Further, scattering particles may be embedded in the sealing material. The scattering particles may be, for example, alumina (Al ₂ O ₃ ), silica (SiO ₂ ), or titania (TiO ₂ ). The scattering particles can effectively scatter the directional light emitted from the LED chip (preferably with negligible absorption).

Scattering particles in a polymer or polymer precursor (especially silicone or silicone epoxy resin or its precursor) for forming a polymer composite layer containing Nd·F (Nd·X·F) on the surface of an LED chip. Can be dispersed. Such materials are well known in the field of LED packaging. The dispersed mixture is coated on the LED chip by any suitable treatment, with particles having a higher density or particle size, or both a higher density and particle size being preferentially set closer to the LED chip and having a composition A graded layer is formed. Fixing can occur during coating or curing of the polymer or precursor and can be facilitated by centrifugation, as is known in the art. Parameters related to the dispersion of the phosphor and Nd·F (Nd·X·F) (eg particle density, such that the light generated by the phosphor component is properly filtered by the Nd·F/Nd·X·F compound). It is further noted that the phosphor material, including particle size and process parameters), may be selected such that the phosphor material is closer to the LED chip 65 than the Nd.F (Nd.X.F) compound.

In an alternative exemplary embodiment shown in FIG. 6b, the phosphor layer 64b may be an encapsulant layer manufactured in a conventional manner, with a separate Nd.F (Nd.X.F) compound. The encapsulant layer 68b can be deposited over the phosphor layer 64b, for example, in a polymer or polymer precursor using any suitable conventional deposition/particle dispersion technique.

In yet another exemplary embodiment shown in FIG. 6c, the outer surface of the dome (shell) 62 may be coated with a Nd.F/Nd.X.F composite layer 68c. The performance of the coated layer 68b is similar to that of the encapsulant layer 68b with the Nd.F (Nd.X.F) compound in Figure 6b. Alternatively, the coating 68c in FIG. 6c can be deposited on the inner surface of the dome 62. Further implementation details regarding the coating of the dome/substrate are described separately with reference to Figures 7-10. It is noted that the dome 62 itself can be transparent or translucent.

In yet another exemplary embodiment, as shown in FIG. 6d, Nd.F/Nd.X.F composite layer/coating 68d on the outer surface of dome 62 and phosphor coating layer 64d on the inner surface of dome 62. A dome (shell) 62 can be used to deposit each. It is further noted that there can be different variations on the approach. For example, both coatings 64d and 68d may be deposited on one surface (outer surface or inner surface) of dome 62 such that phosphor coating 64d is closer to LED chip 65 than coating 68d. The coatings 64d and 68d (if deposited on one side of the dome 62) can also be combined with some layer similar to the encapsulant compound layer 64a of FIG. 6a. It is noted that the dome 62 itself can be transparent, semi-transparent, or semi-transparent to provide various variations on the example shown in FIG. 6d.

Some non-limiting examples of LED lighting devices that produce desired color filtering effects using coatings containing Nd.F and/or Nd.X.F compounds are presented below.

FIG. 7 shows an LED lighting device according to an embodiment of the present invention, which is suitable for area lighting applications. An LED lighting device (also referred to as a "lighting unit" or "lamp") is an LED lamp 70 that can be configured to provide a nearly omnidirectional lighting capability. As shown in FIG. 7, the LED lamp 70 includes a light bulb 72, a base 74, a base 76 between the light bulb 72 and the base 74, and a film 78 on the outer surface of the light bulb 72. The coating 78 includes the Nd.F and/or Nd.X.F compounds described herein. In other embodiments, the bulb 72 may be replaced by other transparent or translucent substrates. Alternatively, the coating 78 may coat the interior surface of the bulb 72 (which may be transparent or translucent).

FIG. 8 shows an LED lighting device according to still another embodiment of the present invention. As shown in FIG. 8, the LED lighting device is a ceiling light 80 (LED chip is not shown). The ceiling light 80 includes a hemispherical base material 82 and a film 88 containing an Nd·F and/or Nd·X·F compound. The coating 88 is on the inner surface of the hemispherical substrate 82. Alternatively, the coating 88 may be coated on the outer surface of the hemispherical substrate 82 (which may be transparent or translucent).

FIG. 9 is an LED lighting device according to still another embodiment of the present invention. As shown in FIG. 9, this LED lighting device is a lens 90, and the lens 90 includes a base material 92 (for example, a flat base material). In the embodiment, the substrate 92 is provided with an Nd.F and/or Nd.X.F compound coating (not shown) on its inner surface and/or outer surface.

FIG. 10 shows an LED lighting device 100 according to another embodiment of the present invention. The LED lighting device 100 includes a light bulb (dome) 102, one or more LED chips 105, and a reflective substrate 106. The reflective substrate 106 is configured to reflect visible light generated by the LED chip 105. In one embodiment described herein, the reflective substrate 106 includes an Nd·F and/or Nd·X·F compound coating (not shown) on its outer surface to provide the desired filtering. .. In FIG. 10, the dome (102) can be made of a diffusing material. In that case, some of the light from the LED will be transmitted and some will be reflected back into the cavity (they depend on the diffusivity of the dome material). The reflected light is specularly reflected or diffusely reflected depending on the diffusivity of the dome 102. Diffuse and/or specularly reflected light from the dome 102 is incident on the reflective substrate 106 coated by one of the embodiments described herein. Alternatively, the dome 102 can be made of a semi-reflective material to provide the same function.

The coating materials described herein, including compounds containing Nd ³⁺ ions and F. ions, may have little optical scattering (diffusing) effect, or may be highly sensitive to light passing through the coating material. It may result in optical scattering. The coating may include discrete particles of organic or inorganic materials to increase the scattering angle. Alternatively, the organic or inorganic material is only composed of discrete particles of Nd·F and/or Nd·X·F compound (eg, partially or wholly formed of Nd·F and/or Nd·X·F compound). And/or at least one discrete particle of Nd·F and/or Nd·X·F compound (eg, partially or wholly formed of Nd·F and/or Nd·X·F compound) It can be composed of a mixture with particles formed of other materials.

In one embodiment, suitable particle sizes for organic or inorganic materials may be from about 1 nm to about 10 μm. In the case of the LED lamp 70 shown in FIG. 7, in order to maximize the scattering angle so that the LED lamp 70 can perform omnidirectional illumination, the particle size is selected to be considerably smaller than 300 nm to maximize the efficiency of Rayleigh scattering. May be.

Without limitation, Nd·F and/or Nd·X·F compound coatings are, for example, spray coated, roller coated, meniscus or dip coated, stamped, screen printed, dispensed, rolled, brushed, bonded. , Electrostatic coating, or any other method capable of achieving a uniform thickness coating. Hereinafter, a method for forming the Nd.F and/or Nd.X.F compound coating on the substrate will be described with reference to three non-limiting examples.

In one embodiment, the coating 78 may be applied to the bulb 72 using an adhesive method, as shown in FIG. The LED lamp 70 may include a bonding layer (not shown) between the light bulb 72 and the coating 78, and the bonding layer may include an organic adhesive or an inorganic adhesive. The organic adhesive may include epoxy resin, organic silicone adhesive, acrylic resin, and the like. Inorganic adhesives can include silicate inorganic adhesives, sulfate adhesives, phosphate adhesives, oxide adhesives, borate adhesives, and the like.

In another embodiment, as shown in FIG. 7, the coating 78 may be applied to the outer surface of the bulb 72 by spray painting. First, a liquid mixture is prepared containing, for example, a NdFO and/or NdF ₃ compound, silicon dioxide, a dispersant (eg Dispex A40), water and optionally TiO ₂ or Al ₂ O ₃ . Next, the manufactured liquid mixture is sprayed onto the electric bulb 72. Finally, the liquid mixture is cured to obtain the LED lamp 70 with the coating.

In one embodiment, as shown in FIG. 7, the coating 78 may be applied to the outer surface of the bulb 72 by electrostatic coating. First, a charged powder composed of, for example, a NdFO and/or NdF ₃ compound, SiO ₂ and Al ₂ O ₃ is produced. The powder is then coated onto the bulb 72, which is charged to the opposite charge.

In other embodiments of the invention, spray coating and electrostatic coating methods may use materials that are free of organic solvents or compounds. Thereby, the service life of the LED lighting device can be extended and the discoloration and fading generally caused by sulfonation can be avoided.

In yet another embodiment, the weight percentage of NdF ₃ or another Nd ³⁺ ion source (eg, by use of Nd·F and Nd·X·F compounds) in the coating is between about 1% and about 20%. May be In one particular embodiment, the weight percentage of NdF ₃ or another Nd ³⁺ ion source in the coating may be from about 1% to about 10%. In another embodiment, the coating further comprises an additive with a higher index of refraction than the Nd.F and/or Nd.X.F compound to promote the refraction of light to obtain a reflective white appearance. You may stay. The additive can be selected from metal oxides and non-metal oxides (eg TiO ₂ , SiO ₂ and Al ₂ O ₃ ).

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. As used herein, the terms "first", "second", etc. do not indicate an order, a quantity, or an importance, but are used to distinguish one element from another. .. Further, the terms "a" and "an" do not indicate the limitation of the quantity but indicate that at least one target object exists. The use of the words "comprising", "comprising", or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms "coupled" and "coupled" are not limited to physical or mechanical connections or couplings and can include electrical and optical connections or couplings, whether direct or indirect. is there.

Furthermore, it will be apparent to those skilled in the art that various features of different embodiments can be interchanged with each other. The various features described, as well as other known equivalents to each feature, can be mixed and matched by one skilled in the art to construct additional systems and methods in accordance with the principles of the present disclosure.

Although specific language is used for the sake of clarity in describing the alternative embodiments of the apparatus defined in the claims, the invention is not limited to the specific language used in the description. Therefore, it should be understood that each specific element includes all technical equivalents that perform the same function by performing the same operation.

It should be understood that the above description is for the purpose of illustration and is not intended to limit the scope of the invention. The scope of the invention is defined by the scope of the appended claims. Other embodiments are within the scope of the following claims.

It is noted that the various non-limiting embodiments described and defined herein can be used separately, in combination, or in selective combination for a particular application.

Moreover, by using some of the various features of the non-limiting embodiments of, the advantages of the invention can be obtained without the corresponding use of the other features described. Therefore, the foregoing description should be considered as merely a description of the principles, teachings and exemplary embodiments of the invention, and not as a limitation of the invention.

Claims (15)

One or more light emitting diode (LED) modules configured to generate visible light;
A compound represented by Nd.X.F added or dispersed in silicone, which is a sealing layer configured to filter visible light (wherein X is O, N, S, Cl, OH, Na, K, Al, Mg, Li, Ca, Sr, Ba and Y).
Said encapsulation layer comprises a phosphor, or said encapsulation layer is deposited on one or more further encapsulation layers comprising a phosphor,
The compound represented by Nd·X·F and the refractive index of silicone are matched, and the compound represented by Nd·X·F has fixed absorption in the visible region of about 530 nm to 600 nm,
apparatus. The device of claim 1 wherein the compound comprises Nd ³⁺ ions and F ⁻ ions . The device of claim 1, wherein the one or more LED modules comprises organic LEDs. The device of claim 1, wherein the encapsulation layer is deposited on top of one or more LED modules. The device according to claim 1, wherein X in the Nd·X·F compound is O or OH . The device of claim 1, wherein the compound is NdFO. One or more light emitting diode (LED) modules configured to generate visible light;
One or more optical elements, wherein the optical element comprises a transparent, semi-transparent or reflective substrate having a coating on the surface,
The coating comprises a compound added to or dispersed in the silicone to filter visible light between about 530 nm and 600 nm,
The compound that filters the visible light is a compound represented by NdXF (where X is O, N, S, Cl, OH, Na, K, Al, Mg, Li, Ca, Sr, Ba and Y is one or more), and the refractive index of the compound represented by Nd.X.F and the silicone are matched.
apparatus. The device of claim 7 , wherein the weight percentage of compound in the coating is from about 1% to about 20%. The device of claim 7 , wherein the coating thickness is from about 50 nm to about 1000 μm. 8. The device of claim 7 , wherein the coating further comprises an additive having a higher refractive index than the compound, the additive being selected from metal oxides and non-metal oxides. Additive is selected from the group consisting of TiO _2, SiO ₂ and Al ₂ O _3, apparatus according to claim 10. The device of claim 7 , wherein the coating is coated on the inner surface of the substrate. The device of claim 7 , wherein the substrate is a diffuser selected from the group consisting of a dome enclosing one or more LED modules, a light bulb and a lens. The device of claim 7 , wherein the optical element further comprises a bonding layer between the substrate and the coating, the bonding layer comprising an organic adhesive or an inorganic adhesive. The apparatus of claim 7 , wherein the coating is applied to the surface of the substrate by either a 5 play coating method or an electrostatic coating method.