JP2009206037A - Led lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an LED lighting system capable of providing human eye-friendly and well-balanced irradiation light. <P>SOLUTION: This LED lighting system 1 includes two or more types of LED units 2, 3 different in color temperature of emitted light. The respective LED units 2, 3 have each an LED light emitting element 24 and a phosphor arranged on its emission surface. The respective LED units 2, 3 adjacent to each other are arranged so that the respective directivity angles thereof partially overlap each other. The two types of LED units 2, 3 preferably have two kinds of emission colors such as white and warm white. The emission quantity of each of the two types of LED units 2 and 3 is controlled by a control device 7. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an LED illumination device, and more particularly to an illumination device composed of at least two types of LED units having different color temperatures of emitted light.

  As an illumination device using an LED (light emitting diode), the one shown in Japanese Patent No. 3165388 has been proposed by the present applicant. In this device, a plurality of casings (partition rooms) partitioned by side walls are formed in a housing, and unit indicator lamps having different display colors are installed in each casing. Each unit indicator lamp emits an LED. The device includes an element and a fluorescent plate disposed above the light emitting surface and containing a fluorescent material.

In each unit indicator, the light of the first wavelength emitted from the LED light emitting element is incident on the fluorescent plate. At this time, a part of the incident light is transmitted through the fluorescent plate, and the remainder of the incident light is fluorescent inside the fluorescent plate. By exciting the material to emit fluorescence, the fluorescent plate emits light having a second wavelength that is longer than the light having the first wavelength. As a result, the emission color of each unit indicator lamp is a color in which the color light of the first wavelength and the color light of the second wavelength are combined.
Japanese Patent No. 3165388 (see paragraph [0021] and FIGS. 1 and 2)

  However, since the conventional lighting device is mainly intended to be used as a display device, each unit indicator is configured to emit light in a different color (see paragraph [0021] of the above publication). For this reason, it cannot be said that it is necessarily suitable as a general lighting device, and it cannot be said that it emits light that is kind to human eyes.

  The present invention has been made in view of such a conventional situation, and the problem to be solved by the present invention is to provide an LED lighting device that can obtain balanced irradiation light that is gentle to human eyes. There is to do.

  The LED lighting device according to the invention of claim 1 has at least two types of LED units having different color temperatures of emitted light. Each LED unit is composed of an LED light emitting element and a phosphor disposed on the light emitting surface thereof, and adjacent LED units are disposed such that their directivity angles partially overlap.

  According to the first aspect of the present invention, at least two types of LED units having different color temperatures of the emitted light are arranged so that their directivity angles partially overlap, so that they are emitted from adjacent LED units. In addition, the respective color lights are superimposed in a space area where the respective directivity angles overlap, and the color lights are mixed in the space area.

  As a result, for example, when two types of LED units of white and warm white are used, the white color alone is too bright as illumination and the eyes are tired easily, or the warm white color alone is somewhat unsatisfactory However, by combining the two in combination, it is possible to obtain an intermediate color between them, thereby obtaining a well-balanced irradiation light that is friendly to human eyes.

  As described in the invention of claim 2, at least two types of LED units preferably have two types of luminescent colors, white and warm white.

  In the invention of claim 3, in claim 1 or 2, at least two types of LED units are arranged alternately.

  In this case, the color mixture by each irradiation light from each LED unit can be evenly arranged with good balance without being unevenly distributed in the irradiation space region.

  According to a fourth aspect of the invention, there is further provided a control device according to the third aspect, wherein the control device controls the light emission amounts of at least two types of LED units.

  In this case, the amount of light emitted from each LED unit is controlled by the control device, so that the mixing ratio of each irradiation light from each LED unit can be adjusted. Or the hue of the mixed color can be changed according to the season.

  As described above, according to the LED lighting device according to the present invention, at least two types of LED units having different color temperatures of emitted light are arranged so that the respective directivity angles partially overlap each other. Each color light emitted from the LED unit is overlapped and mixed with each other in a space area where the respective directivity angles overlap, and thereby, a balanced illumination light that is gentle to the human eye. There is an effect that can be obtained.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 to 7 are views for explaining an LED lighting device according to an embodiment of the present invention. FIG. 1 is a front (bottom) view of the LED lighting device according to an embodiment of the present invention, and FIG. FIG. 3 is a schematic view of the back side (upper surface), FIG. 3 is a schematic vertical sectional view of the LED unit constituting the LED lighting device, and FIG. 4 is a diagram illustrating the directivity angles of the adjacent LED units and the state in which they overlap. FIG. 5 is a diagram showing the relative energy distribution of white light, warm white light and mixed color light emitted from the LED unit, and FIG. 6 is a blue color for comparison with FIG. FIG. 7 is a control block diagram of the LED illumination device, and FIG. 7 is a diagram illustrating relative energy distributions of blue light, green light, and red light emitted from the LED, green LED, and red LED.

  FIG. 1 is a view of the LED illumination device 1 as viewed from the lower surface side (that is, the emission surface side). As shown in FIG. 1, the LED illumination device 1 has two types of different color temperatures of emitted light. The LED units 2 and 3 are alternately arranged. The LED unit 2 is preferably an LED unit that emits white light (for example, a color temperature of 5400K or the vicinity thereof), and the LED unit 3 is preferably warm white light (for example, a color temperature of 3300K or the vicinity thereof). LED units that emit light are used. The LED units 2 and 3 are accommodated in a housing unit 4 configured in a rectangular frame shape (that is, so as to form each side of the rectangle). The housing unit 4 is attached to a recess provided in the ceiling surface 100. Further, the housing unit 4 has a plurality of compartments 11 separated from each other via a partition wall 10, and the lower surface of each compartment 11 is covered with a translucent cover 12, for example, made of resin. (The resin cover 12 of the compartment 11 in the upper right corner of FIG. 1 is omitted). Each LED unit 2 and 3 is attached to the top plate 13 in each compartment 11 (see the compartment 11 in the upper right corner of the figure).

  FIG. 2 is a view of the LED lighting device 1 as viewed from the upper surface side (that is, the side opposite to the emission surface). As shown in FIG. 2, the power circuit unit 5, 6 is provided. The power circuit unit 5 is for applying a voltage to the white LED unit 2, and the power circuit unit 6 is for applying a voltage to the warm white LED unit 3.

  FIG. 3 is a schematic vertical sectional view of the LED unit 2. As shown in the figure, the LED unit 2 includes substrates 21 and 22 stacked on an aluminum plate 20, and a plurality of LED light emitting elements 24 mounted on the substrate 22, and the LED light emitting elements 24 are made fluorescent. It is configured by sealing with a body-containing silicon sealing material 25.

  In this example, the LED light emitting element 24 is a light emitting diode that emits blue light. The phosphor dispersedly contained in the silicon sealing material 25 has a fluorescence characteristic that it is excited by the incident light and emits light having a wavelength different from that of the incident light when returning to the ground state. In the example, a material that emits yellow fluorescence having a wavelength longer than that of blue light when excited by blue light is used. Thereby, the light radiate | emitted from LED unit 2 turns into white which mixed blue light and yellow light.

  Although not shown, the LED unit 3 has the same configuration as the LED unit 2 and uses a light emitting diode that emits blue light as an LED light emitting element. The body is different. Here, the phosphors are a phosphor that emits green fluorescence having a wavelength longer than that of blue light when excited by blue light, and a phosphor that similarly emits orange fluorescence having a wavelength longer than that of blue light. Different types of phosphors are used. Thereby, the light emitted from the LED unit 3 becomes warm white in which blue light, green light, and orange light are mixed.

  Moreover, as each LED unit 2 and 3, what has a wide directivity angle is preferable. FIG. 4 shows irradiation light emitted from the adjacent LED units 2 and 3 each having a directivity angle of about 120 °. As shown in the figure, each irradiation light partially overlaps. In the figure, an area indicated by A is an irradiation area of the LED unit 2, and an area indicated by B is an irradiation area of the LED unit 3. A hatched area indicated by C is an area in which each irradiation light from the LED units 2 and 3 is mixed. For example, when the color temperature of the white light from the LED unit 2 is about 5400K and the color temperature of the warm white light from the LED unit 3 is about 3300K, the color temperature of the mixed color region C is about 4200K. Note that the color of the mixed color region C is the color on the line segment when the positions of white light and warm white light are plotted in the chromaticity diagram and the positions are connected by line segments.

  Next, FIG. 5 shows the relative energy distribution of the white light and warm white light emitted from the LED units 2 and 3 together with the relative energy distribution of the mixed light of the white light and warm white light. Has been. On the other hand, FIG. 6 shows relative energy distributions of blue light, green light, and red light emitted from the blue LED, green LED, and red LED, respectively, for comparison with FIG.

  As can be seen by comparing these figures, in the case of white light, it has a first peak value (maximum peak value) of relative energy at a substantially central position in the blue light wavelength region, It has a second peak value at a position near the long wavelength. In the case of warm white light, it has a first peak value of relative energy at a substantially central position in the blue light wavelength region, and a second peak value (maximum peak) at a position closer to the longer wavelength in the green light wavelength region. Value). In both cases of white light and warm white light, the curve including the second peak value draws a gentle curve, and from the position near the short wavelength of the green light wavelength region to the wavelength region of red light. It extends to a wide wavelength region up to a position beyond the long wavelength region. That is, the wavelength region is broadened.

  In the case of mixed light of white and warm white, it has a first peak value (maximum peak value) of relative energy at a substantially central position in the wavelength region of blue light and is closer to a longer wavelength in the wavelength region of green light. The curve including the second peak value has a gentle curve and draws a gentle curve from the position near the short wavelength in the wavelength range of green light to the wavelength range of red light. Of these, it extends to a wide wavelength region up to a position exceeding the long wavelength region. That is, the wavelength region is broadened. The relative energy of the mixed color light is higher than the relative energy of the white light and the warm white light over the entire wavelength region included in the mixed color light.

  In contrast, the relative energy distributions of blue, green, and red emitted from the blue LED, green LED, and red LED, respectively, exist in a narrow wavelength region.

  FIG. 7 is a control block diagram of the LED lighting device 1. As shown in the figure, a control device 7 is connected to each of the power supply circuits 5 and 6. The control device 7 controls the value of the current flowing through each LED light emitting element by controlling the voltage applied to each power supply circuit 5, 6. Thereby, the emitted light quantity of the light radiate | emitted from each LED light emitting element can be adjusted, As a result, the mixing ratio of white and warm white can be changed.

  In the LED lighting device configured as described above, the white LED unit 2 and the warm white LED unit 3 are arranged so as to partially overlap the respective directivity angles. 3 are superposed in a space area C (see FIG. 4) in which the respective directivity angles overlap, and these color lights are mixed in the space area.

  As shown in FIG. 5, the wavelength of the mixed color light extends widely from the short wavelength region to the long wavelength region of visible light.

  Thereby, the balanced irradiation light which is kind to human eyes can be obtained. In addition, the white color alone is too bright and the eyes are easily tired, and the warm white color alone is slightly unsatisfactory. It is possible to obtain irradiation light that is more gentle to human eyes.

  In addition, as shown in FIG. 6, the wavelength of each monochromatic light of blue light, green light, or red light emitted from a blue LED, green LED, or red LED extends to a very narrow region, and this Such peak light itself is tired to the eyes of humans and is not appropriate as illumination. Further, when these peak lights are mixed, very high relative energy mixed light can be obtained, and such mixed light only makes the eyes of the human tired.

  Moreover, according to this LED illuminating device, the white LED unit 2 and the warm white LED unit 3 are alternately arranged, so that the color mixture by the irradiation light from each LED unit 2, 3 is performed in the irradiation space region. Can be arranged evenly with good balance without being unevenly distributed.

  Furthermore, according to this LED illuminating device, by providing the control device 7 for controlling the light emission amount of each LED unit 2, 3, the light emission amount of each LED unit 2, 3 is controlled, and each LED unit The mixing ratio of each irradiation light from 2 and 3 can be adjusted. Thereby, for example, the hue of the mixed color can be changed according to the usage of the room or according to the season.

  More specifically, in summer, a cool space is produced by relatively increasing the amount of light emitted by the white LED unit 2 (and relatively decreasing the amount of light emitted by the warm white LED unit 3). In the winter, on the contrary, the warm white LED unit 3 can be warmed by relatively increasing the amount of light emitted (and relatively reducing the amount of light emitted by the white LED unit 2). A certain space can be produced. When the light emission amount of the LED unit 2 is increased by the control of the control device 7, the color mixture in the color mixture region C (FIG. 4) also changes to an intermediate color slightly biased to the white side. Similarly, the LED unit 3 When the amount of emitted light is increased, the color mixture in the color mixture region C (FIG. 4) also changes to an intermediate color slightly biased toward the warm white side.

  Although the said Example demonstrated what was comprised in the rectangular frame shape as an LED illuminating device, application of this invention is not limited to this. 8 and 9 show an LED lighting device according to another embodiment of the present invention.

  FIG. 8 is a view of the LED lighting device 8 as viewed from the lower surface side (outgoing surface side). As shown in the figure, the LED lighting device 8 has a rectangular area drilled in the ceiling surface. The white LED unit 2 and the warm white LED unit 3 are alternately arranged in the same manner as in the above embodiment. Each of the LED units 2 and 3 is accommodated one by one in a plurality of compartments 81 that are separated from each other via a plurality of partition walls 80 arranged in a lattice shape. The lower surface of each compartment 81 is covered with, for example, a resin cover 82 having translucency (the resin cover 82 of the compartment 81 in the upper right corner of FIG. 8 is omitted). Each LED unit 2, 3 is attached to its top plate 83 in each compartment 81 (see the compartment 81 in the upper right corner of the figure). In this case, a grid-like checkered pattern of white and warm white is configured by alternately arranging the LED units 2 and 3.

  Even in this case, since the LED units 2 and 3 are arranged so that the irradiation light areas of the adjacent LED units 2 and 3 overlap, the irradiation of the adjacent LED units 2 and 3 is performed. The overlap region of light becomes a mixed intermediate color of white and warm white, so that it is possible to obtain balanced irradiation light that is gentle to human eyes.

  FIG. 9 is a view of the LED lighting device 9 as viewed from the lower surface side (outgoing surface side). As shown in FIG. 9, the LED lighting device 9 has a circular area drilled in the ceiling surface. Preferably, the white LED units 2 and the warm white LED units 3 are alternately arranged in the circumferential direction. In this case, the central LED unit 2 may be omitted, or the LED unit 3 may be provided instead of the central LED unit 2. Alternatively, the LED unit 2 may be disposed at the center and only the LED unit 3 may be disposed so as to surround the periphery thereof, or the LED unit 3 may be disposed at the center and surrounded by the LED unit 3. Only two may be arranged. In this case, the LED units 2 and 3 are alternately arranged in the diameter direction.

  Even in this case, since the LED units 2 and 3 are arranged so that the irradiation light areas of the adjacent LED units 2 and 3 overlap, the irradiation of the adjacent LED units 2 and 3 is performed. The overlap region of light becomes a mixed intermediate color of white and warm white, so that it is possible to obtain balanced irradiation light that is gentle to human eyes.

  In addition, in the said Example and other Example, although the white LED unit 2 and the warm white LED unit 3 were shown as an LED unit from which the color temperature of emitted light differs, the application of this invention is shown. It is not limited to the combination of these two types of LED units, and in addition to white and warm white, an LED unit that emits another color may be combined. It is also possible to combine four or more types of LED units. Further, the combination of colors is not limited to those including white and warm white.

1 is a surface view of an LED lighting device according to an embodiment of the present invention. It is a back surface schematic diagram of a LED lighting apparatus (FIG. 1). It is a longitudinal cross-sectional schematic diagram of the LED unit which comprises an LED illuminating device (FIG. 1). It is a figure for demonstrating each directional angle of each LED unit adjacent, and the state in which they overlap. It is a figure which shows each relative energy distribution of the white light radiate | emitted from the LED unit, warm white light, and these mixed color light. FIG. 6 is a diagram showing relative energy distributions of blue light, green light, and red light emitted from a blue LED, a green LED, and a red LED for comparison with FIG. 5. It is a control block diagram of LED lighting apparatus (FIG. 1). FIG. 6 is a surface view of an LED lighting device according to another embodiment of the present invention. FIG. 6 is a surface view of an LED lighting device according to still another embodiment of the present invention.

Explanation of symbols

1: LED lighting device

2: LED unit (white)
24: LED light emitting element 25: Silicon encapsulant containing phosphor

3: LED unit (warm white)

7: Control device

C: Mixed color area

Claims (4)

An LED lighting device,
Having at least two types of LED units having different color temperatures of emitted light;
Each of the LED units has an LED light emitting element and a phosphor disposed on the light emitting surface thereof, and the adjacent LED units are disposed such that their directivity angles partially overlap each other.
LED lighting device characterized by the above. In claim 1,
The at least two types of LED units have two types of emission colors, white and warm white,
LED lighting device characterized by the above. In claim 1 or 2,
The at least two types of LED units are arranged alternately.
LED lighting device characterized by the above. In any of claims 1 to 3,
A control device for controlling the light emission amount of each of the at least two types of LED units;
LED lighting device characterized by the above.