LED light-emitting devices and lighting fixtures

Abstract

To provide LED light-emitting devices and lighting fixtures with excellent color rendering at high color temperatures. [Solution] A light-emitting device comprising one or more LED elements and multiple phosphors, wherein the extracted light from the light-emitting device has a color temperature of 8400 to 10000K, an average color rendering index Ra of 95 or higher, and a special color rendering index R9 of 88 or higher. Furthermore, the extracted light from the light-emitting device has chromaticity coordinates of 0.27 to 0.29 and 0.30 to 0.32 in the chromaticity diagram of the CIE1931 color system.

Description

[Technical Field]

[0001] This invention relates to an LED light-emitting device and lighting fixture that take into consideration color rendering at high color temperatures. [Background technology]

[0002] While it has become common practice to consider color rendering in LED light-emitting devices and lighting fixtures, consideration has been insufficient regarding color rendering at high color temperatures of 7500K or higher (correlated color temperature hereinafter simply referred to as "color temperature").

[0003] Patent Document 1 describes an LED light-emitting device that includes a blue LED with a predetermined peak wavelength and a plurality of phosphors, and by setting the ratio of the emission intensity at 480nm, 530nm, and 550nm to the emission intensity at the peak wavelength within a predetermined range, the yellow component of the emission is reduced and the blue component is relatively increased, thereby improving the legibility of text and other objects when viewed by elderly people with reduced visual sensitivity to blue light. Examples of high color temperatures in this device include one with a color temperature of 7855K, an average color rendering index Ra of 93.2, and a special color rendering index R9 of 87.5, and another with a color temperature of 8465K, an Ra of 91.8, and an R9 of 79.5.

[0004] Patent Document 2 describes a blue LED with a predetermined peak wavelength and Ce 3+ The present invention describes an LED light-emitting device that emits highly color-rendering light by comprising two distinct first and second phosphors activated by a certain method, and an optical filter placed between the two phosphors. Examples of the embodiment with a high color temperature include one with a color temperature of 7500K, an Ra of 93.1, and an R9 of 84.3, and another with a color temperature of 8000K, an Ra of 93.2, and an R9 of 86.8. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2023 / 074525 [Patent Document 2] International Publication No. 2019 / 124046 [Overview of the project] [Problems that the invention aims to solve]

[0006] As described above, even conventional LED light-emitting devices that claimed to have taken color rendering into consideration only achieved Ra of 91.8 to 93.2 and R9 of 79.5 to 87.5 at high color temperatures of 7500 to 8465K, indicating insufficient consideration.

[0007] Therefore, the object of the present invention is to provide an LED light-emitting device and lighting fixture that exhibits excellent color rendering at high color temperatures. [Means for solving the problem]

[0008] [1] A light-emitting device comprising one or more LED elements and a plurality of phosphors, The light extracted from the light-emitting device is an LED light-emitting device with a color temperature of 8400-10000K, an average color rendering index Ra of 95 or higher, and a special color rendering index R9 of 88 or higher.

[0009] [2] A light-emitting device comprising one or more LED elements and a plurality of phosphors, The light extracted from the light-emitting device is an LED light-emitting device with chromaticity coordinates of 0.27 to 0.29 and 0.30 to 0.32 in the chromaticity diagram of the CIE1931 color system.

[0010] [3] A light-emitting device comprising one or more LED elements and a plurality of phosphors, The light extracted from the light-emitting device is an LED light-emitting device in which the chromaticity coordinates of the CIE1931 color system are x 0.27 to 0.29 and y 0.30 to 0.32, and the color temperature is 8400 to 10000K, the average color rendering index Ra is 95 or higher, and the special color rendering index R9 is 88 or higher.

[0011] [4] The extraction light is the LED light-emitting device described in [1] above, having a color temperature of 9000 to 10000 K and special color rendering evaluation numbers R10, R11, R12, R13, R14, and R15 all being 85 or more.

[0012] [5] The extraction light is the LED light-emitting device described in [2] above, having a color temperature of 9000 to 10000 K and special color rendering evaluation numbers R10, R11, R12, R13, R14, and R15 all being 85 or more.

[0013] [6] The extraction light is the LED light-emitting device described in [3] above, having a color temperature of 9000 to 10000 K and special color rendering evaluation numbers R10, R11, R12, R13, R14, and R15 all being 85 or more.

[0014] [7] A light-emitting device including one or more LED elements and a plurality of phosphors, wherein the extraction light taken out from the light-emitting device is an LED light-emitting device having a color temperature of 8400 to 10000 K, an average color rendering evaluation number Ra of 95 or more, and a special color rendering evaluation number R9 of 94 or more.

[0015] [8] The extraction light is the LED light-emitting device according to any one of [1] to [7] above, having a melanopic ratio of 1.2 to 1.4.

[0016] [9] A lighting fixture including the LED light-emitting device according to any one of [1] to [8] above.

Effect of the Invention

[0017] According to the present invention, it is possible to provide an LED light-emitting device and a lighting fixture excellent in color rendering at a high color temperature.

Brief Description of the Drawings

[0018] [Figure 1] FIG. 1 is a cross-sectional view of the LED light-emitting devices of the examples and the comparative examples. [Figure 2] FIG. 2 is a light emission spectrum diagram of the extraction light of the examples and the comparative examples. [Figure 3]Figure 3 is a chromaticity diagram showing the chromaticity coordinates in the chromaticity diagram of the extracted light of the examples and comparative examples. [Modes for carrying out the invention]

[0019] <1> LED light LED elements include laser diode elements. The emission peak wavelength of the LED element is not particularly limited, but is preferably in the range of 315 to 460 nm, and more preferably in the range of 380 to 430 nm.

[0020] <2> One or more LED elements and multiple phosphors "One or more LED elements and multiple phosphors" includes the following embodiments: A single LED element and multiple phosphors excited by the light emitted by the LED element. There are multiple combinations of one LED element and one or more phosphors excited by the light emitted by the LED element.

[0021] <3> Phosphors A phosphor is a substance that emits fluorescence using the light emitted by an LED element as an excitation source. The phosphor is preferably a group of phosphors composed of multiple types of phosphors. The phosphor is • A blue phosphor having an emission peak in 445-490 nm, • A green phosphor having an emission peak in 491-570 nm, • An orange phosphor having an emission peak in 571-600 nm, It is preferable to include a red phosphor having an emission peak in the 601-670 nm range. This is to improve color rendering.

[0022] Blue phosphors are • A blue phosphor having an emission peak at 445-455 nm, It is more preferable to include two types of blue phosphors having emission peaks in the 456-490 nm range, in order to improve color rendering.

[0023] The red phosphor is ·Preferably, it contains two types of red phosphors having emission peaks at 601 to 650 nm and ·red phosphors having emission peaks at 651 to 670 nm. This is to enhance the color rendering property.

[0024] The composition of the blue phosphor is not particularly limited, but (Sr, Ba) 10 (PO4)6Cl2:Eu 2+ Those having a composition represented by are preferred. This is to enhance the color rendering property. The composition of the green phosphor is not particularly limited, but Si 3~5.99 Al 0.01~3 O 0.01~3 N 5~7.99 :Eu 0.001~0.1 Those having a composition represented by are preferred. This is to enhance the color rendering property. The composition of the orange phosphor is not particularly limited, but Ca 0.25~2 Si 0.01~11.49 Al 0.51~11.99 O 0.01~11.49 N 4.51~15.99 :Eu 0.001~0.1 Those having a composition represented by are preferred. This is to enhance the color rendering property. The composition of the red phosphor is not particularly limited, but CaAlSiN3:Eu 2+ Those having a composition represented by are preferred. This is to enhance the color rendering property.

[0025] <6>Chromaticity coordinates As described above, the extracted light preferably has chromaticity coordinates in the chromaticity diagram of the CIE1931 color system, where x is 0.27 to 0.29 and y is 0.30 to 0.32, and more preferably x is 0.27 to 0.285 and y is 0.30 to 0.32.

Examples

[0026] Next, examples embodying the present invention will be described with reference to the drawings while comparing with comparative examples. Note that the materials, quantities, and conditions of each part of the examples are illustrative and can be appropriately changed without departing from the gist of the invention.

[0027] As shown in Figure 1, the LED light-emitting device 1 of the embodiment comprises a substrate 10, an LED element 2 bonded to the substrate 10, and a first sealing material 3 that encapsulates the LED element 2. The first sealing material 3 consists of a transparent resin 4 and a phosphor 5 dispersed in the resin 4.

[0028] The white light extracted from the LED light-emitting device 1 of the embodiment has a color temperature of 8400 to 10000K, an average color rendering index Ra of 95 or higher, and a special color rendering index R9 of 88 or higher. In contrast, the comparative example LED light-emitting device has the same structure as the example shown in Figure 1, but the characteristics of the extracted light differ from those of the example. For details, the LED light-emitting devices of Examples 1-8 and Comparative Examples 1-3 shown in Table 1 were fabricated as follows, and the characteristics of the extracted light were measured.

[0029] [Table 1]

[0030] In Table 1, the LED element is a gallium nitride-based LED element manufactured by Toyoda Gosei Co., Ltd., which emits violet light with a peak wavelength of 405 nm. The resin used is T-122 silicone resin manufactured by Aica Kogyo Co., Ltd. VB202A3 is the product number for a blue phosphor (SBCA) manufactured by Mitsubishi Chemical Corporation. VB202B3 is the product number for a blue phosphor (SBCA) manufactured by Mitsubishi Chemical Corporation. GR540K is the product number for a green phosphor (β-sialon) manufactured by Denka Co., Ltd. YL595B is the product number for the orange phosphor (α-Sialon) manufactured by Denka Co., Ltd. VR-103C is the product number for a red phosphor (CASN) manufactured by Mitsubishi Chemical Corporation. R660 is the product number for a red phosphor (CASN) manufactured by Denka Co., Ltd.

[0031] (Manufacturing method) An LED element 2 was mounted on a substrate 10 and made electrically conductive. The phosphors shown in Table 1 were mixed with the resin in the proportions shown in Table 1 per 1 g of resin, and the mixture was mixed using a stirrer or the like to uniformly disperse the phosphors in the resin. This mixture of resin and phosphors was applied to the LED element 2 using a dispenser or the like in the amount shown in Table 1. The resin was heated and cured in an oven to make a encapsulant 3, and LED light-emitting devices 1 for Examples 1 to 8 and Comparative Examples 1 to 3 were fabricated.

[0032] (Characteristics of extracted light) Light was extracted from each LED light-emitting device 1 in Examples 1-8 and Comparative Examples 1-3 by the light emitted by the LED element 2 and the phosphor 5 when power was applied. The measurement results for each extracted light are shown below.

[0033] (1) Emission spectrum Figure 2 shows the emission spectrum.

[0034] (2) Color temperature, etc. Table 2 shows the color temperature (correlated color temperature), chromaticity coordinates in the chromaticity diagram, melanopic ratio, special color rendering indices R1 to R15, and average color rendering index Ra.

[0035] [Table 2]

[0036] Here, the melanopic ratio is the ratio of the equivalent melanopic illuminance, calculated using a melanopic sensitivity curve with a peak at a wavelength of 490 nm, to the normal illuminance. Given the spectral distribution curve E(λ), the melanopic sensitivity curve C(λ), and the luminous efficiency curve V(λ) of the light source, the ratio is expressed by the following equation (1). A high melanopic ratio has the effect of suppressing the secretion of melatonin, a sleep-inducing hormone.

[0037]

number

[0038] (2) Chromaticity coordinates Figure 3 shows the chromaticity coordinates (chromaticity points) in the chromaticity diagram.

[0039] (summary) Comparative Examples 1 and 2 have color temperatures of 10343K and 10376K, respectively, and have low Ra and R9 values. Comparative Example 3 has a color temperature of 7383K, an Ra value that does not reach 95, and a low R9 value. In contrast to these, Examples 1-8 have a color temperature of 8400-10000K, an average color rendering index Ra of 95 or higher, and a special color rendering index R9 of 88 or higher, demonstrating excellent color rendering at high color temperatures. This is thought to be due to the chromaticity coordinates being 0.27-0.29 and 0.30-0.32 for x. In particular, Examples 1-3 and 8 have a color temperature of 9000-10000K, and R10, R11, R12, R13, R14, and R15 are all 85 or higher. This means that the product meets the high color rendering class 4 standard at a color temperature outside the color temperature range (2600K-7100K) defined by JIS Z 9112:2019, and can be considered a unique high color rendering capability. Furthermore, Examples 4-8 have an R9 of 94 or higher, demonstrating particularly excellent color rendering. Furthermore, Examples 1-8 had a melanopic ratio of 1.2-1.4, indicating that they suppress the secretion of the sleep-inducing hormone melatonin and promote daytime wakefulness (taking circadian rhythms into consideration).

[0040] It should be noted that the present invention is not limited to the embodiments described above, and can be appropriately modified and implemented without departing from the spirit of the invention. [Explanation of Symbols]

[0041] 1. Light-emitting device 2 LED chips 3. Sealing material 4 resin 5. Phosphors 10 circuit boards

Claims

1. A light-emitting device comprising one or more LED elements and a plurality of phosphors, The light extracted from the light-emitting device is an LED light-emitting device with a color temperature of 8400 to 10000K, an average color rendering index Ra of 95 or higher, a special color rendering index R9 of 88 or higher, and a melanopic ratio of 1.2 to 1.

4.

2. A light-emitting device comprising one or more LED elements and a plurality of phosphors, The extracted light from the light-emitting device is an LED light-emitting device with chromaticity coordinates in the CIE 1931 color system chromaticity diagram where x is 0.27 to 0.29, y is 0.30 to 0.32, and the melanopic ratio is 1.2 to 1.

4.

3. A light-emitting device comprising one or more LED elements and a plurality of phosphors, The light extracted from the light-emitting device is an LED light-emitting device in which the chromaticity coordinates of the CIE 1931 color system chromaticity diagram are such that x is 0.27 to 0.29 and y is 0.30 to 0.32, and the color temperature is 8400 to 10000 K, the average color rendering index Ra is 95 or higher, the special color rendering index R9 is 88 or higher, and the melanopic ratio is 1.2 to 1.

4.

4. The LED light-emitting device according to claim 1, wherein the extracted light has a color temperature of 9000 to 10000K, and the special color rendering indices R10, R11, R12, R13, R14, and R15 are all 85 or higher.

5. The LED light-emitting device according to claim 2, wherein the extracted light has a color temperature of 9000 to 10000K, and the special color rendering indices R10, R11, R12, R13, R14, and R15 are all 85 or higher.

6. The LED light-emitting device according to claim 3, wherein the extracted light has a color temperature of 9000 to 10000K, and the special color rendering indices R10, R11, R12, R13, R14, and R15 are all 85 or higher.

7. A light-emitting device comprising one or more LED elements and a plurality of phosphors, The light extracted from the light-emitting device is an LED light-emitting device with a color temperature of 8400 to 10000K, an average color rendering index Ra of 95 or higher, a special color rendering index R9 of 94 or higher, and a melanopic ratio of 1.2 to 1.

4.

8. A lighting fixture equipped with an LED light-emitting device according to any one of claims 1 to 7.

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