Light emitting device

Abstract

To provide a light emitting device which emits light in a belt-like manner, which can perform desired light distribution more precisely by a cover part for covering a light emitting part and a side part at the side part of it, and which has few dead angles.SOLUTION: A light emitting device includes: a substrate formed in a belt-like shape; a plurality of light emitting parts mounted on a substrate, and arranged in the full length direction of the substrate; a belt-like cover part for covering the plurality of light emitting parts, and formed on the substrate; and a side part formed in a belt-like shape or a linear shape on the substrate along the cover part, and arranged on the end side in the width direction of the cover part in a cross-sectional view. The cover part is constituted by a material having light transmissivity so as to diffuse light radiated from the light emitting part. The side part is constituted by a material having higher light reflectivity than the cover part, and is constituted so as to reflect at least part of the light that has transmitted the cover part to the cover part side, and the swollen amount from the substrate of the cover part is made to be larger than the side part.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a light-emitting device that emits light in a strip shape. [Background technology]

[0002] A light emitting device is known which comprises a substrate formed in a strip shape, a plurality of light emitting units mounted on the substrate and aligned along the entire length of the substrate, and a cover unit formed in a strip shape on the substrate while covering the plurality of light emitting units, the cover unit being made of a light-transmitting material, and which diffuses and homogenizes light irradiated from the light emitting units within the cover unit (see, for example, Patent Document 1).

[0003] Furthermore, as an improvement on the light-emitting device of Patent Document 1, a light-emitting device has been publicly known in which side portions are formed in a strip or line shape on the substrate along the cover portion and are positioned on the widthwise end side of the cover portion when viewed in cross section, and light that passes from the light-emitting portion through the cover portion and is irradiated onto the side portions is reflected by the side portions (see, for example, Patent Document 2).

[0004] According to the light emitting device of Patent Document 2, reflection at the side portions makes it possible to distribute the light more precisely as desired, but since the amount of bulging of the cover portion from the substrate is smaller than the amount of bulging of the side portions from the substrate, there is a drawback in that it is difficult to confirm the light when viewing the light emitting device from the side. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Utility Model Registration No. 3162845 [Patent Document 2] Japanese Patent Publication No. 2020-091952 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention aims to provide a light-emitting device that emits light in a stripe shape, which is capable of achieving a more precise desired light distribution by using a cover portion that covers the light-emitting portion and side portions on either side of the cover portion, and which has fewer blind spots. [Means for solving the problem]

[0007] In order to solve the above problem, a light emitting device that emits light in a strip-like manner comprises a substrate formed in a strip-like shape, a plurality of light emitting units mounted on the substrate and aligned along the entire length of the substrate, a cover unit formed in a strip-like shape on the substrate while covering the plurality of light emitting units, and side units formed in a strip-like or linear shape on the substrate along the cover unit and positioned on the widthwise end side of the cover unit in a cross-sectional view, wherein the cover unit is made of a light-transmitting material so as to diffuse light irradiated from the light emitting units, the side units are made of a material with a higher light reflectivity than the cover unit and are configured to reflect at least a portion of the light that has passed through the cover unit toward the cover unit, and the cover unit bulges out from the substrate by a larger amount than the side units.

[0008] The side portions may be provided on both ends of the cover portion in the width direction in a cross-sectional view.

[0009] The light distribution portion, which is at least one of the cover portion and the side portion, may be provided on the substrate by dispensing a fluid material onto the substrate and then hardening it.

[0010] The light distribution section may be made of a resin material that hardens by drying and / or cooling.

[0011] The light distribution portion may be made of a silicon material. [Effects of the Invention]

[0012] Since the cover portion bulges out from the substrate more than the side portion, the emitted light can be seen from the side, and the light transmitted through the cover portion spreads to the side without being obstructed by the side portion, so blind spots are reduced and the cover portion and side portion can precisely distribute the light as desired. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a plan view showing the configuration of an illumination device to which the present invention is applied. [Figure 2] 1 is an enlarged side view showing the configuration of a lighting device to which the present invention is applied. [Figure 3] FIG. 2 is an electrical circuit diagram showing the configuration of a light-emitting unit. [Figure 4] 3 is a side cross-sectional view showing the configuration of a lighting device equipped with the tape light of FIGS. 1 and 2. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] 1 and 2 are a plan view and an enlarged side view showing the configuration of a lighting device to which the present invention is applied. The lighting device includes a tape light (light-emitting device) 1 to which the present invention is applied, and a power supply device 2 that supplies power to the tape light 1.

[0015] For convenience, the following description will be given assuming that the thickness direction of the light strip 1 is the up-down direction, the lit side is the upper side, and the overall length direction of the light strip 1 is the left-right direction. However, the position of the light strip 1 can, of course, be set to any direction.

[0016] The power supply unit 2 is configured to convert household AC voltage into DC voltage and output it. The voltage (power) output from the power supply unit 2 is supplied to the strip light 1 via a power cable 3 that integrates a voltage application line 3a to which the voltage is applied and a ground line 3b that serves as a reference (0 V).

[0017] The light strip 1 includes one or more (single in this example) flexible substrates (substrates) 4 formed in a strip shape along its entire length (tape direction). When the light strip 1 is made up of multiple flexible substrates 4, the multiple flexible substrates 4 are arranged in a line and adjacent ends of the flexible substrates 4 are electrically and physically connected to form the light strip 1.

[0018] The flexible substrate 4 has a plurality of light-emitting units 6 arranged linearly along its entire length, and is integrally formed as a whole. The light-emitting units 6 are formed in a strip shape along the tape direction, and the ends of adjacent units are electrically connected.

[0019] The flexible substrate 4 can be cut into individual light-emitting units 6. For example, the tape light 1 (flexible substrate 4) shown in Fig. 1 has five integrated light-emitting units 6, but if a sufficient length can be ensured with four light-emitting units 6, the light-emitting unit 6 that is farthest from the power supply 2 in terms of the electrical circuit (in the illustrated example, the fifth light-emitting unit 6 from the power supply 2) may be cut to form the tape light 1 using four light-emitting units 6.

[0020] That is, the length of the tape light 1 can be freely selected for each light emitting unit 6, and it is also possible to configure one tape light 1 or flexible substrate 4 from as little as one light source.

[0021] 3 is an electrical circuit diagram showing the configuration of the light-emitting unit. The light-emitting unit 6 is composed of a part or all (part in the illustrated example) of the flexible substrate 4. On this light-emitting unit 6, there are mounted a closed circuit 10 in which a plurality of light-emitting circuits (light-emitting sections) 9, each of which is made up of a plurality of (two in the illustrated example) LEDs (light-emitting elements) 8 connected in parallel, and a constant current element 11 are electrically connected in series, a voltage application side circuit 12, and a ground side circuit 13.

[0022] Each LED 8 is mounted on the flexible substrate 4 with the irradiation direction facing the side where the LED 8 is provided in the thickness direction of the flexible substrate 4 (i.e., directly upward in this example, hereinafter referred to as the "irradiation direction"). Incidentally, the LEDs may be mounted by soldering chips to the flexible substrate 4, or may be formed directly on the circuit of the flexible substrate 4 by printing or the like.

[0023] The voltage application side circuit 12 has an input port 12a, an output port 12b, and a connection line 12c that electrically connects these.

[0024] The input port 12a of the light-emitting unit 6 arranged closest to the power supply device 2 in terms of electrical wiring is connected to the voltage application line 3a, while the input ports 12a of the other light-emitting units 6 are electrically connected to the output ports 12b of the voltage application side circuits 12 of the other adjacent light-emitting units 6 on the side closer to the power supply device 2 in terms of electrical wiring.

[0025] Nothing is connected to the output port 12b of the light-emitting unit 6 that is located farthest from the power supply device 2 in terms of electrical wiring, while the output ports 12b of the other light-emitting units 6 are electrically connected to the input ports 12a of the voltage application side circuits 12 of other adjacent light-emitting units 6 that are farthest from the power supply device 2 in terms of electrical wiring.

[0026] The ground side circuit 13 has an input port 13a, an output port 13b, and a connection line 13c that electrically connects these.

[0027] The input port 13a of the light-emitting unit 6 arranged closest to the power supply device 2 in terms of electrical wiring is connected to the ground line 3b, while the input port 13a of the other light-emitting units 6 is electrically connected to the output port 13b of the voltage application side circuit 12 of the other adjacent light-emitting unit 6 on the side closer to the power supply device 2 in terms of electrical wiring.

[0028] Nothing is connected to the output port 13b of the light-emitting unit 6 that is located farthest from the power supply device 2 in terms of electrical wiring, while the output ports 13b of the other light-emitting units 6 are electrically connected to the input ports 13a of the voltage application side circuits 12 of other adjacent light-emitting units 6 that are farthest from the power supply device 2 in terms of electrical wiring.

[0029] The closed circuit 10 is wired between the connection wire 12c of the voltage application side circuit 12 and the connection wire 13c of the ground side circuit 13, and the forward direction of each LED 8 is set so that electricity flows from the connection wire 12c of the voltage application side circuit 12 to the connection wire 13c of the ground side circuit 13.

[0030] Each constant current element 11 is a constant current regulator (CCR) that supplies a constant current regardless of the applied voltage. The reason why a CCR is used as the constant current element 11 instead of a constant current diode (CRD) is that a CCR is more susceptible to power supply noise than a CRD, operates at a lower voltage, and is compact in size. The constant current regulator 11 used in this example operates normally over a wide temperature range of -40 to 165°C, and obtains a substantially constant current of around 19 mA over a voltage range of 0.6 to 36.0 V.

[0031] The voltage range differs depending on the type of constant current regulator 11, and is changed as appropriate depending on the desired light intensity, the number of installed LEDs 8, etc. In addition, the constant current regulator 11 of this example is capable of applying a voltage of 0.3 to 40.0 [V].

[0032] Incidentally, the light emitting circuits 9 are arranged at predetermined intervals along the entire length of the tape light 1 (light emitting units 6).

[0033] 1 and 2, in the present tape light 1, the light emitting unit 9 (LEDs 8) mounted on the flexible substrate 4 is covered and protected from the direction of irradiation by a cover unit (light distribution unit) 14 formed on the flexible substrate 4. In other words, the light emitting unit 9 is sealed by the cover unit 14.

[0034] The cover portion 14 is made of a translucent silicone (resin) material and is formed in a strip shape on the flexible substrate 4 while covering the plurality of light-emitting portions 9. The cover portion 14 is white or a color close to white. One or more cover portions 14 are provided on one light strip 1. In this example, one cover portion 14 covers all of the plurality of light-emitting portions 9 provided on the light strip 1. The cover portion 14 introduces light from the light-emitting portions 9 and diffuses the light therein, thereby emitting light uniformly.

[0035] Band-shaped side portions (light distribution portions) 16, 16 are formed on both sides in the width direction of the cover portion 14. In this example, each side portion 16 is provided over the entire length of the cover portion 14. Note that a side portion 16 may be provided in a partial range of the cover portion 14, or multiple side portions 16 may cover the entire range of the cover portion 14.

[0036] The side portions 16 are made of a material (in this example, a silicone (resin) material) that has a higher light reflectivity than the cover portion 14. The amount of bulging of each side portion 16 from the flexible substrate 4 is set to be smaller than the amount of bulging of the cover portion 14 from the flexible substrate 4. This prevents the side portions 16 from becoming blind spots, making it difficult to see the light from the light emitting portion 9 from the sides of the tape light 1.

[0037] The side portions 16 reflect at least a portion of the light leaking out laterally from the cover portion 14 and return it back into the cover portion 14. This action makes the light from the light-emitting portion 9 even more uniform.

[0038] Next, the procedure for providing the cover portion 14 and the side portion 16 on the flexible substrate 4 will be described. A silicone material sealed in a container or the like in a fluid state is poured onto the flexible substrate 4, and then hardened by drying, cooling, or the like, to form the cover portion 14 and the side portion 16 on the substrate 4. The order in which the cover portion 14 and the side portion 16 are provided on the flexible substrate 4 does not matter.

[0039] Incidentally, if the cover portion 14 is provided first, it becomes easier to subsequently form the side portion 16. On the other hand, if the pair of side portions 16, 16 are provided first, the widthwise range of the cover portion 14 on the flexible substrate 4 is defined, making it easier to form the cover portion 14. In addition, since the cover portion 14 is also formed on the side portion 16, the side portion 16 will be embedded into the side of the cover portion 14 after hardening.

[0040] With the tape light 1 configured as described above, the pair of side sections 16, 16 arranged on both sides of the cover section 14 allows the cover section 14 to emit light more uniformly. In particular, by adjusting the amount of bulging of the side sections 16, 16 as described above, the light from the side sections 16 is also emitted laterally. This makes it possible to achieve a wide illumination angle (close to 180°) as shown by the imaginary line in FIG. 2.

[0041] Furthermore, the risk of breakdown is reduced because the various electrical circuits on the flexible substrate 4, including the LEDs 8, are protected by being sealed with the cover 14. Incidentally, heat from these electrical circuits can be dissipated from the side of the flexible substrate 4 on which the LEDs 8 are not provided.

[0042] It is also possible to replace each of the plurality of light emitting circuits 9 with a single LED 8. Furthermore, the substrate 4 may be made of a hard material and may be non-flexible.

[0043] Next, an example of a lighting device using this tape light 1 will be described with reference to FIG.

[0044] Fig. 4 is a side cross-sectional view showing the configuration of an illumination device including the tape light of Fig. 1 and Fig. 2. The illumination device 50 shown in the figure includes a belt-shaped, plate-shaped support member 51 on which the flexible substrate 4 of the tape light 1 is placed and fixed, a belt-shaped, plate-shaped base member 52, a fixing member 53 that fixes the support member 51 on the base member 52, and a cover member 54 that covers a space including the tape light 1, the support member 51, the base member 52, and the fixing member 53 on the surface of the base member 52 facing the tape light 1.

[0045] The light strip 1 is placed on the support member 51 in a plate-like shape and fixed to the support member 51 by adhesive or the like. The fixing member 53 fixes the support member 51 onto the base member 52 with a predetermined gap therebetween. In other words, the fixing member 53 also functions as a spacer that ensures a space between the support member 51 (light strip 1) and the base member 52. The cover member 54 is made of a light-transmitting (more specifically, transparent) hard synthetic resin or glass material.

[0046] The lighting device 50 configured as described above can ensure uniform, bright light by utilizing the wide illumination angle of the tape light 1. In addition, heat from the flexible substrate 4 is conducted to the support member 51 and efficiently dissipated from the space between the support member 51 and the base member 52.

[0047] If the substrate 4 of the light emitting device 1 is made of a hard material, the support member 51 can be omitted. [Explanation of symbols]

[0048] 1. Tape light (light-emitting device) 2 Power supply 4 Flexible PCB (PCB) 8 LED (light-emitting element) 9 Light emitting circuit (light emitting part) 14 Cover part (light distribution part) 16 Side part (light distribution part)

Claims

1. A light-emitting device that emits light in a strip shape, a substrate formed in a strip shape; a plurality of light emitting units mounted on the substrate and arranged in the overall length direction of the substrate; a cover portion formed in a strip shape on the substrate in a state of covering a plurality of light emitting portions; a side portion formed in a strip or line shape on the substrate along the cover portion and disposed on an end side of the cover portion in a width direction in a cross-sectional view; the cover portion is made of a light-transmitting material so as to diffuse the light emitted from the light-emitting portion, the side portion is made of a material having a higher light reflectivity than the cover portion and is configured to reflect at least a portion of the light transmitted through the cover portion toward the cover portion, The cover portion protrudes from the substrate by a larger amount than the side portions. A light-emitting device characterized by:

2. The side portions are provided on both ends of the cover portion in the width direction in a cross-sectional view. The light emitting device according to claim 1 .

3. The light distribution portion, which is at least one of the cover portion and the side portion, is provided on the substrate by dispensing a fluid material onto the substrate and then hardening it. The light emitting device according to claim 1 .

4. The light distribution section is made of a resin material that hardens by drying and / or cooling. The light emitting device according to claim 3 .

5. The light distribution section is made of a silicon material. The light emitting device according to claim 4 .

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