JP2023027971A - Lighting device - Google Patents

Abstract

To provide a lighting device that emits warm-colored light having excellent color rendering property of red color and suppressed in color rendering property of blue color, as a replacement for a halogen lamp.SOLUTION: A lighting device includes: a daylight-colored LED 15b1 emitting daylight-colored light; a bulb-colored LED 15b2 emitting bulb-colored light; a red-colored LED 15b5 emitting red-colored light; and a blue-green-colored LED 15b3 emitting blue-green-colored light. The red-colored LED 15b5 emits light having a peak wavelength within a range of 610-750 nm and the blue-green-colored LED 15b3 emits light having a peak wavelength within a range of 470-490 nm.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to a lighting device including light emitting elements of multiple colors as light sources.

BACKGROUND ART As a background art of the present invention, a lighting device described in Japanese Patent Laying-Open No. 2020-181809 (Patent Document 1) is known. The lighting device of Patent Document 1 includes a daylight color LED that emits daylight color light, a light bulb color LED that emits light bulb color, and a bluish green LED that emits bluish green light. or on the outermost circumference, or on the innermost and outermost circumferences (see summary). Furthermore, Patent Document 1 describes that a red LED or the like may be substituted for a blue-green LED, or that a blue-green LED, a red LED, a light bulb color LED, and a daylight color LED may be used (paragraph 0111).

Japanese Unexamined Patent Application Publication No. 2020-181809

Patent document 1 does not consider the wavelength of red light used together with blue-green light.

SUMMARY OF THE INVENTION An object of the present invention is to provide a lighting device that irradiates warm color light with high color rendering properties for red and suppressed color rendering properties for blue as an alternative to halogen bulbs.

The present invention includes a daylight LED that emits daylight color light, a bulb color LED that emits bulb color light, a red LED that emits red light, and a blue-green LED that emits blue-green light, and the red LED The light emitted from has a peak wavelength in the range of 610 nm to 750 nm, and the light emitted from the blue-green LED has a peak wavelength in the range of 470 nm to 490 nm.

According to the present invention, it is possible to realize a lighting device that emits warm color light with low cost, high color rendering of red, and suppressed color rendering of blue as a substitute for halogen bulbs.

Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

1 is an exploded perspective view showing an LED lighting device according to an embodiment of the present invention; FIG. FIG. 2 is a plan view showing the arrangement of color LEDs of the LED lighting device according to one embodiment of the present invention; 1 is a vertical cross-sectional view showing an LED lighting device according to an embodiment of the present invention; FIG. 4 is an enlarged cross-sectional view of the LED cover portion of FIG. 3; FIG. 1 is a control block diagram of an LED lighting device according to an embodiment of the present invention; FIG. FIG. 4 is a spectral distribution diagram for obtaining light with a correlated color temperature of 3000K using daylight color LEDs and warm white LEDs used in the LED lighting device according to an embodiment of the present invention. FIG. 4 is a spectral distribution diagram for obtaining light with a correlated color temperature of 3000K using a daylight color LED, a light bulb color LED, and a red LED used in an LED lighting device according to an embodiment of the present invention; It is a figure which shows the relationship between photopic luminosity and the wavelength of light. FIG. 4 is a spectral distribution diagram for obtaining light with a correlated color temperature of 3000K using a daylight color LED, a light bulb color LED, a red LED, and a bluish green LED used in an LED lighting device according to an embodiment of the present invention; 10 shows the measurement results of the color rendering index of the illumination light shown in the spectral distributions of FIGS. 6, 7 and 9 and the illumination light of the halogen lamp.

In lighting equipment, halogen bulbs use an infrared reflective film to suppress heat radiation, so food can be prevented from heating up by lighting, creating a calm atmosphere with warm colors. etc. has been widely used. On the other hand, in recent years, lighting devices using white light emitting elements (LEDs: Light Emitting Diodes) have rapidly spread, and are used as ceiling lighting devices (so-called ceiling lights) in the dining room and living room of the home. Conventional lighting such as light bulbs, halogen light bulbs, and fluorescent lights are being replaced.

White LED emits less infrared rays, can suppress food from heating by lighting like a halogen light bulb, and is relatively easy to adjust the light color. A warm light of 3000K is also feasible.

On the other hand, a white LED uses a blue LED and a phosphor that converts the blue light emitted from the blue LED into yellow light to create white light. There is a problem that the color rendering of red is low and the appearance of red foods such as meat is poor compared to halogen bulbs.

The embodiment according to the present invention includes a red LED, a blue-green LED that has a complementary color relationship with red and further compensates for the radiant intensity at a wavelength of 470 to 490 nm, which is likely to be insufficient in the white LED, and a light bulb color that emits light in the color of an incandescent bulb. To provide a lighting device that irradiates warm color light with high red color rendering property as an alternative to a halogen light bulb by using LEDs and daylight LEDs.

More specifically, the embodiment according to the present invention includes a light bulb color LED that emits light of light bulb color, a daylight color LED that emits light of daylight color for adjusting the light color, and a radiant intensity of a wavelength of 610 to 750 nm. The light color is adjusted with a red LED that enhances, a blue-green LED that supplements the radiant intensity of the wavelength of 470 to 490 nm that is complementary to red and tends to be insufficient for white LEDs, and a light bulb color LED that emits light of light bulb color. and a daylight LED that emits daylight color light for the purpose, the peak intensity of the red light emitted by the red LED is the highest when expressed in terms of spectral distribution, and the light bulb color LED and the daylight light bulb color LED are daylight colors in the circumferential direction It is preferable that the LEDs are arranged in a plurality of rows concentrically with the LEDs interposed therebetween, and the red LEDs and the blue-green LEDs are arranged on the innermost circumference, the outermost circumference, or the innermost circumference and the outermost circumference.

According to the present embodiment, it is possible to realize an illumination device that emits warm color light with a high color rendering property of red at a low cost as an alternative to the halogen lamp.

An LED lighting device (LED ceiling light) according to an embodiment of the present invention will now be described in detail with reference to the drawings. In addition, the LED lighting device 1A according to the present embodiment can be installed, for example, through a mounting adapter (not shown) that engages with an indoor wiring device (not shown) such as a hanging rosette or a hanging ceiling provided on the ceiling surface of a house. , is used by being connected to an external power source and fixed at a predetermined position on the ceiling surface.

FIG. 1 is an exploded perspective view showing an LED lighting device according to one embodiment of the present invention. In FIG. 1, the upper side of the paper surface is the ceiling side, and the lower side of the paper surface is the floor side. In this case, the ceiling side is the fixed side of the LED lighting device 1A, and the floor side is sometimes called the non-fixed side or the surface side.

As shown in FIG. 1, the LED lighting device 1A is, for example, a round type, and includes a main body base 11, an adapter receiving portion (insulating material) 12, a power supply substrate 13, a heat dissipation plate 14, an LED light source substrate 15, and a reflection sheet 16. , an LED cover 17, a center cover 18, a shade 19, a ring member 20, a sensor unit 21, and the like.

The main body base 11 is a component formed by processing a steel plate (for example, SPCC) into a substantially circular shape, and is formed in a substantially concave shape (dish shape) so that the concave surface faces the floor side. An adapter mounting hole 11a is formed in the center of the main body base 11 to receive a mounting adapter (not shown).

The adapter receiving portion (insulating material) 12 is made of a flame-retardant synthetic resin (for example, PBT: polybutylene terephthalate resin), and includes a ring-shaped fixing portion 12a that is screwed to the main body base 11 and the fixing portion 12a. and a cylindrical portion 12b extending from the inner peripheral edge portion of 12a to the floor side (downward).

The power supply board 13 has a lighting circuit board including a control section and the like, and is screwed to the main body base 11 via an adapter receiving section (insulating material) 12 . As a result, the power supply substrate 13 is arranged in a heat radiation space surrounded by the main body base 11 and a heat radiation plate 14, which will be described later, while maintaining electrical insulation.

Also, the power supply board 13 is electrically connected to a mounting adapter (not shown) via an electric wire (not shown). As a result, the LED lighting device 1A is supplied with power via the indoor wiring fixture (not shown), the mounting adapter (not shown), and the power board 13, respectively.

The radiator plate 14 is formed by processing a steel plate into a substantially circular shape, and has a truncated conical substrate support portion 14a protruding toward the floor. The heat sink 14 is made of a metal having good thermal conductivity, such as a galvanized steel plate, and is squeezed to improve its strength. The radiator plate 14 is formed to have a larger diameter than the main body base 11 and is attached to the main body base 11 so as to protrude radially outward from the main body base 11 .

A circular through-hole 14b is formed in the radial center of the radiator plate 14 at a position corresponding to the cylindrical portion 12b of the adapter receiving portion (insulating material) 12 . Further, on the annular portion 14c formed on the outer periphery of the radiator plate 14, holders 14d for hooking shades 19, which will be described later, are attached at three locations at intervals of 120°.

The LED light source board 15 includes a ring-shaped wiring board 15a and a plurality of LED element groups 15b concentrically arranged on one surface side (floor surface side) of the wiring board 15a. Details of the LED element group 15b will be described later.

The wiring board 15a is formed, for example, by forming an insulating layer and a copper foil pattern on a substantially annular metal plate made of an aluminum alloy, or is formed on a flat plate of a resin with good thermal conductivity (for example, polyimide resin). It is configured by forming a copper foil pattern and a solder resist. Also, the wiring board 15a is fixed to the radiator plate 14 with screws.

In this embodiment, by providing the main body base 11 and the heat sink 14 configured as described above, the volume of the heat sink space is increased (the amount of air in the heat sink space is increased), and the power supply board 13 and the LED light source board are mounted. 15 is intended to improve the heat dissipation efficiency. As a result, the luminous efficiency of the LED element group 15b can be increased.

FIG. 2 is a plan view showing the arrangement of color LEDs in an LED lighting device according to an embodiment of the present invention. Note that FIG. 2 shows an example of the arrangement pattern of the LEDs, and the number and arrangement of the LEDs can be adjusted, and is not limited to this.

As shown in FIG. 2, the LED element group 15b includes a plurality of daylight color LEDs (Light Emitting Diodes) 15b1 that emit daylight color (D color) light, and a plurality of light bulb color LEDs 15b2 that emit light bulb color (L color). , a plurality of red LEDs 15b5 emitting red light, and a plurality of blue-green LEDs 15b3 emitting blue-green light. Moreover, the LED element group 15b is equipped with LED15b4 for night lights.

The daylight LEDs 15b1 have a peak wavelength of 430 nm to 460 nm, and are formed in a plurality of rows (10 rows in FIG. 2) concentrically from the outer peripheral side to the inner peripheral side.

The light bulb-colored LEDs 15b2 have a peak wavelength of 550 nm to 650 nm, and are arranged with the daylight-colored LEDs 15b1 interposed in each row arranged concentrically.

The red LED 15b5 has a peak wavelength of 610 to 750 nm, and the blue-green LED 15b3 has a peak wavelength of 470 nm to 490 nm. A daylight color LED 15b1 and a light bulb color LED 15b2 are arranged in a row on the outer periphery. The LEDs arranged on the outermost circumference have a strong light distribution to the outside, and the LEDs arranged on the innermost circumference have a strong light distribution to the inside. , the effect of arranging light over a wide range is exhibited.

In the concentric row except for the outermost and innermost circumferences, the bulb-colored LEDs 15b2 are arranged with two or three daylight-colored LEDs 15b1 sandwiched therebetween. Since the light amount distribution of the daylight color and the light bulb color to obtain the correlated color temperature of the daylight color of about 5000K is about 2:1, by arranging in this way, the quantity ratio of the daylight color LED 15b1 and the light bulb color LED 15b2 is set to about 2:1. By causing the LEDs of each color to emit light with approximately the same current, an effect of making the lighting device with high luminous efficiency is obtained.

In addition, in each concentric row in which the daylight color LED 15b1, the light bulb color LED 15b2, the red LED 15b5, and the blue-green LED 15b3 are arranged, the LEDs are arranged at equal intervals or approximately equal intervals in the circumferential direction. By arranging in this way, there is an effect of obtaining light distribution with little color unevenness in the circumferential direction.

The LED element group 15b shown in FIG. 2 includes, for example, 274 daylight color LEDs 15b1, 152 light bulb color LEDs 15b2, 20 red LEDs 15b5, and 12 blue-green LEDs 15b3. Thus, the total number of the red LEDs 15b5 and the blue-green LEDs 15b3 is preferably about 10% of the total number of the daylight-colored LEDs 15b1 and the bulb-colored LEDs 15b2. Also, from the viewpoint of enhancing the color rendering of red, the number of red LEDs 15b5 is preferably larger than that of blue-green LEDs 15b3 in order to enhance red light, and the number of red LEDs 15b5 is preferably about twice that of blue-green LEDs 15b3.

Returning to FIG. 1, the reflective sheet (reflective film) 16 has a function of reflecting the light emitted toward the ceiling from the LED element group 15b (the light reflected toward the ceiling by the LED cover 17 and the shade 19) toward the floor. and is formed in a donut shape (annular shape) in plan view so as to correspond to the shape of the LED light source substrate 15 . The reflective sheet 16 is made of a white resin sheet, and is formed with through holes 16a through which the respective elements of the LED element group 15b are individually exposed (inserted). In this embodiment, the case where the reflective sheet 16 is provided has been described as an example, but the present invention is not limited to this, and a configuration in which the heat sink 14 and the light source substrate 15 are coated with a highly reflective coating may be employed. . In this embodiment, the use of the reflective sheet 16 instead of the highly reflective coating makes it possible to manufacture the LED lighting device 1A at low cost.

The LED cover 17 has a function of guiding the luminous flux emitted from the plurality of LED element groups 15b to the surface side (floor side) and a function of pressing the LED light source substrate 15 so as to be in close contact with the heat sink 14. there is

The LED cover 17 is integrally formed by injection molding or the like using a translucent and electrically insulating resin such as polystyrene or polycarbonate. In particular, it is preferable to use polystyrene in terms of transparency, cost and moldability. Further, the material used for the LED cover 17 is not limited to resin as long as it has translucency and electrical insulation, and may be glass or the like.

The LED cover 17 includes a substantially circular LED cover portion 17a that covers the entire light emitting surface (the surface on which the LED element group 15b is mounted) of the LED light source substrate 15, and an LED cover portion 17a that extends from the outer peripheral edge portion of the LED cover portion 17a to the rear side. It has a cylindrical wall portion 17b extending toward (ceiling side) and a flange portion 17c protruding radially outward from the upper end (back side) of the wall portion 17b. The flange portion 17c extends along the circumferential direction and is divided into three portions.

The center cover 18 covers the mounting adapter (not shown) exposed at the center of the apparatus main body, and is made of, for example, a flame-retardant synthetic resin (eg, PP: polypropylene resin). Also, the center cover 18 is formed in a disc shape and is detachably attached to the LED cover 17 .

The shade 19 is made of a translucent (including transparent, translucent, or opalescent) resin (for example, acrylic or polystyrene) and has a dome shape. In addition, the shade 19 diffuses the luminous flux emitted from the light source (the LED element group 15b) to reduce glare when the user looks directly at the LED lighting device 1A, or to reduce glare when the LED lighting device 1A is installed. It plays the role of equalizing the brightness of the space. Further, the shade 19 is detachably engaged and held by the receiver 14d of the radiator plate 14. As shown in FIG.

The ring member 20 is configured such that the inner peripheral side of the ring portion is held on the outer peripheral side of the shade 19 and the outer peripheral side of the ring portion protrudes outside the outer periphery of the shade 19 . Further, the ring member 20 is made of a material having optical transparency.

For example, the sensor unit 21 changes the power supplied to the LED element group 15b according to the brightness of the environment (space) in which the LED lighting device 1A is installed, so that a constant illuminance can be obtained under the LED lighting device 1A. Provides functionality to do so. Also, the illuminance under the LED lighting device 1A is detected.

FIG. 3 is a longitudinal sectional view showing an LED lighting device according to one embodiment of the present invention.

As shown in FIG. 3 (also shown in FIG. 1), the LED cover portion 17a has a circular through-hole 17a1 formed in the center portion in the radial direction. Further, dome-shaped portions 17a2 are formed in the LED cover portion 17a at positions corresponding to the LED element groups 15b (daylight color LED 15b1, light bulb color LED 15b2, red LED 15b5, blue-green LED 15b3) of the LED light source substrate 15, respectively. The dome-shaped portion 17a2 has a lens function, and diffuses the luminous fluxes from the daylight color LED 15b1, the light bulb color LED 15b2, the red LED 15b5, and the blue-green LED 15b3.

In the LED cover 17, the LED cover portion 17a is screwed to the board support portion 14a of the heat sink 14, and the collar portion 17c is screwed to the annular portion 14c of the heat sink 14. As shown in FIG.

The wall portion 17b is formed extending in a direction substantially orthogonal to the LED cover portion 17a. A notch (not shown) is formed in the wall portion 17b so that the heat inside the LED cover 17 can escape to the outside. The opening area of the notch is set to a size that the user's finger cannot be inserted into. This prevents the user from directly touching the LED light source board 15 with his/her hand (finger).

The flange portion 17 c is a fixing portion that fixes the LED cover 17 to the heat sink 14 on the outer peripheral side of the LED light source substrate 15 .

4 is an enlarged sectional view of the LED cover portion of FIG. 3. FIG. In FIG. 4, the arrows indicate the light distribution of the light emitted from the LEDs arranged at the innermost peripheral portion (a), the outermost peripheral portion (c), and the intermediate position (b).

The innermost peripheral portion (a) refers to the innermost peripheral row in each concentric row in which the daylight color LED 15b1, the light bulb color LED 15b2, the red LED 15b5, and the blue-green LED 15b3 are arranged, and the outermost peripheral portion (c). indicates the outermost row, and the intermediate position (b) indicates the row therebetween. Intermediate positions (b) may be single row or multiple rows.

The luminous flux emitted from the LED arranged at the intermediate position (b) becomes diffused light 151b by the dome shape 171b of the LED cover. In the diffused light 151b, the luminous flux radiated at an angle close to vertical reaches the shade 19 (not shown) as it is, but the luminous flux radiated at an angle close to the horizontal reaches the closely arranged dome shape 172b and is reflected with the reflected light 152b. Light 153b is emitted after being incident on the dome shape 172b. Reflected light 152b and emitted light 153b from dome shape 172b are bent in the vertical direction, so diffused light 151b has a narrowed light distribution.

The luminous flux emitted from the LED arranged in the innermost peripheral portion (a) becomes diffused light 151a due to the dome shape 171a of the LED cover. In the diffused light 151a, the luminous flux radiated at an angle close to vertical and the luminous flux radiated in the inner peripheral direction reach the shade 19 (not shown) as they are, but the luminous flux radiated in the outer peripheral side at an angle close to the horizontal are closely arranged. The light reaches the dome shape 172a, and becomes reflected light 152a and light 153a that is emitted after being incident on the dome shape 172a. Since the reflected light 152a and the emitted light 153a from the dome shape 172a are bent in the vertical direction, the diffused light 151a has a narrower light distribution on the outer peripheral side.

The luminous flux emitted from the LED arranged in the outermost peripheral portion (c) becomes diffused light 151c by the dome shape 171c of the LED cover. In the diffused light 151c, the luminous flux emitted at an angle close to vertical and the luminous flux emitted toward the outer peripheral side reach the shade 19 (not shown) as they are, but the luminous flux emitted toward the inner peripheral side at an angle close to the horizontal are closely arranged. The light reaches the dome shape 172c, and becomes reflected light 152c and light 153c that is emitted after being incident on the dome shape 172c. Since the reflected light 152c and the emitted light 153c from the dome shape 172c are bent in the vertical direction, the light distribution of the diffused light 151c is narrowed on the inner peripheral side.

As described above, there are no adjacent domes outside the LEDs arranged on the outermost circumference and inside the LEDs arranged on the innermost circumference. Good light distribution is obtained in the outer direction of the LEDs and the inner direction of the LEDs arranged on the innermost periphery.

As shown in FIG. 2, by arranging the red LED 15b5 and the blue-green LED 15b3 on the innermost circumference and the outermost circumference, it is possible to efficiently distribute light from a small number of the red LED 15b5 and the blue-green LED 15b3 over a wide range.

FIG. 5 is a control block diagram of an LED lighting device according to one embodiment of the present invention.

As shown in FIG. 5, the LED lighting device 1A operates by being supplied with power from a power supply PS (or commercial power supply) and a power supply circuit . The power supply circuit 130 has a function of adjusting the power of the power supply PS to a predetermined voltage or current.

The LED lighting device 1A also includes a light receiving section 110 . The light receiving unit 110 has a function of receiving a signal (for example, infrared light) output from the remote controller 120 by button operation of the remote controller 120 and transmitting the received signal to the control unit 101 .

The remote control 120 has a button (not shown) operated by a person, and has a function of outputting a signal set for the operated button. For example, daylight color mode, warm color mode, warm color mode + red LED + blue-green LED addition mode, etc. can be set.

Next, a functional example of the LED lighting device 1A will be described.
The LED lighting device 1A includes a control unit 101, dimming circuits 102 and 103 for dimming the daylight color LED 15b1 and the light bulb color LED 15b2, respectively, a lighting circuit 104 for lighting and extinguishing the red LED 15b5 and the blue-green LED 15b3, the daylight color LED 15b1, and the light bulb color LED 15b2. , a red LED 15b5, and a blue-green LED 15b3 (light source). The lighting circuit 104 for lighting/extinguishing the red LED 15b5 and the blue-green LED 15b3 may be separately provided with a lighting circuit for lighting/extinguishing the red LED 15b5 and a lighting circuit for lighting/extinguishing the blue-green LED 15b3. Using one lighting circuit 104 is preferable because the cost can be reduced. Moreover, illustration is abbreviate|omitted about LED15b4 for security lights demonstrated in FIG.

The control unit 101 includes a microcomputer and the like, and has a function of receiving a signal received by the light receiving unit 110 and generating a control signal for controlling the dimming circuits 102 and 103 and the lighting circuit 104 . The control signal is, for example, a PWM (Pulse Width Modulation) signal. The control unit 101 is configured by a CPU (Central Processing Unit) and a main memory, and expands an application program stored in a storage unit (not shown) into the main memory to implement its function.

The dimming circuits 102 and 103 drive the daylight color LED 15b1 and the light bulb color LED 15b2 based on the control signal received from the control unit 101, and the lighting circuit 104 has a function of driving the red LED 15b5 and the blue-green LED 15b3. In addition, the dimming circuits 102 and 103 have a function of individually changing the drive currents for driving the daylight color LED 15b1 and the light bulb color LED 15b2 based on the control signal received from the control unit 101. FIG. Further, the lighting circuit 104 has a simple configuration that has a function of switching between a lighting state and a non-lighting state of the red LED 15b5 and the blue-green LED 15b3 based on the control signal received from the control unit 101, and does not have a function of changing the drive current. is. Note that the lighting circuit 104 may have a function of individually changing the drive current to be driven in the same manner as the dimming circuits 102 and 103, so that it is possible to provide a lighting device capable of adjusting a wider range of light colors. Since the operation by the operator becomes complicated, the control circuit becomes complicated, and the number of circuit parts increases, it is preferable to have a simple configuration that does not have the function of changing the drive current.

FIG. 6 is a spectral distribution diagram for obtaining light with a correlated color temperature of 3000K using daylight-colored LEDs and warm-white LEDs used in an LED lighting apparatus according to an embodiment of the present invention. FIG. 6 shows the spectral distribution of the light emitted from the LED lighting device 1A when the daylight color LED 15b1 and the light bulb color LED 15b2 are adjusted by the dimming circuits 102 and 103 to emit light with a correlated color temperature of 3000K. . In this embodiment, the relationship between the wavelength of light and the radiant intensity will be described as a spectral distribution diagram.

The daylight LED 15b1 has a peak wavelength in the range of 430 nm to 460 nm, and in this embodiment, one having a peak wavelength of 450 nm is used. The correlated color temperature of the daylight LED 15b1 is 6500K (Kelvin). The light bulb color LED 15b2 has a peak wavelength in the range of 550 nm to 650 nm, and in this embodiment, one having a peak wavelength of 610 nm is used. The correlated color temperature of the light bulb color LED 15b2 is 2700K.

The correlated color temperature of the daylight color LED 15b1 and the light bulb color LED 15b2 is not limited to 6500K or 2700K.

FIG. 7 is a spectral distribution diagram for obtaining light with a correlated color temperature of 3000K using daylight color LEDs, light bulb color LEDs, and red LEDs used in an LED lighting apparatus according to an embodiment of the present invention. In FIG. 7, the daylight color LED 15b1, the light bulb color LED 15b2, and the red LED 15b5 are used, and the light control circuits 102 and 103 and the lighting circuit 104 are adjusted to emit light with a correlated color temperature of 3000 K from the LED lighting device 1A. It shows the spectral distribution of the emitted light.

The red LED 15b5 has a peak wavelength in the range of 610 nm to 750 nm, and in this embodiment, one having a peak wavelength of 630 nm is used.

FIG. 8 is a diagram showing the relationship between photopic luminosity and wavelength of light. As shown in the photopic luminous efficiency shown in FIG. 8, the brightness perceived by humans decreases as the wavelength becomes longer with a peak at 555 nm. Preferably, the red LED 15b5 has a peak wavelength in the range of 610 nm to 650 nm in terms of light wavelength. That is, red light close to orange is used.

FIG. 9 is a spectral distribution diagram for obtaining light with a correlated color temperature of 3000K using daylight color LEDs, light bulb color LEDs, red LEDs, and blue-green LEDs used in the LED lighting apparatus according to an embodiment of the present invention. In FIG. 9, the daylight color LED 15b1, the light bulb color LED 15b2, the red LED 15b5, and the blue-green LED 15b3 are used, and the LEDs are adjusted to emit light with a correlated color temperature of 3000 K by the dimming circuits 102 and 103 and the lighting circuit 104. The spectral distribution of light emitted from the lighting device 1A is shown.

The blue-green LED 15b3 has a peak wavelength in the range of 470 nm to 490 nm, and in this embodiment, one having a peak wavelength of 475 nm is used. In other words, bluish-green light close to green light is used.

FIG. 10 shows the measurement results of the color rendering index of the illumination light shown in the spectral distributions of FIGS. 6, 7 and 9 and the illumination light of the halogen lamp. FIG. 10 shows the measurement results of color rendering properties R9, R6, and R12. R9, R6, and R12 are the color rendering indexes for color numbers 9, 6, and 12 of test colors described in JIS Z 8726 (1990), respectively. Color number 9 is red, color number 6 is light blue, and color number 12 is dark blue.

According to the measurement results of FIG. 10, the halogen lamp has a high R9 value of 75. On the other hand, in the spectral distribution of FIG. 6 realized only by the daylight color LED 15b1 and the light bulb color LED 15b2, R9 is 35, which is a low color rendering property of red. In the spectral distribution of FIG. 7 realized by the daylight color LED 15b1, the light bulb color LED 15b2, and the red LED 15b5, R9 is 75, and the red color rendering property is enhanced to the same extent as the halogen light bulb. In the spectral distribution of FIG. 9 realized by the daylight LED 15b1, the light bulb color LED 15b2, the red LED 15b5, and the blue-green LED 15b3 to which blue-green light, which is the complementary color of red, is added, R9 is 93, and the color rendering property of red is that of halogen. It can be obtained higher than a light bulb, and can suppress the blue color rendering properties R6 and R12, which are said to dampen appetite.

In this way, the daylight color LED 15b1, the light bulb color LED 15b2, the red LED 15b5, and the blue-green LED 15b3 that emits blue-green light, which is the complementary color of red, enhance the color rendering of red and suppress the color rendering of blue, which is said to attenuate appetite. be able to. The luminous fluxes due to the spectral distributions of FIGS. 6, 7, and 9 are all set to have the same value. The ratio of the luminous fluxes of the daylight color LED 15b1 and the light bulb color LED 15b2 in the spectral distribution of FIG. :60:4, and the ratio of the luminous fluxes of the daylight color LED 15b1, light bulb color LED 15b2, red LED 15b5, and blue-green LED 15b3 in the spectral distribution of FIG. 9 is approximately 20:72:5:3.

In this embodiment, the light emitted from the LED lighting device 1A is warm light with a correlated color temperature of 2600K to 3250K. The light emitted from the LED lighting device 1A has a color rendering index R9 of 75 or more, R6 of 75 or less, and R12 of 60 or less. Moreover, the peak of the radiant intensity in the spectral distribution of the light emitted from the LED lighting device 1A has the same light wavelength as the peak of the light emitted from the red LED 15b5.

The luminous flux ratio described above is merely an example, and the optimal ratio differs depending on the characteristics of the daylight color LED 15b1, light bulb color LED 15b2, red LED 15b5, and blue-green LED 15b3, so the luminous flux ratio is not limited to the above.

The points of the technical idea of this embodiment can be summarized as follows.
In this embodiment, the following points are taken into consideration as problems.
(1) The red color rendering property is equivalent to that of a halogen bulb, or even higher.
(2) The blue color rendering is suppressed more than the halogen lamp.

For this reason, in this embodiment, blue-green light is added to red light to compensate for the original lack of blue-green light, and to mix red light and blue-green light that are complementary colors. to bring it closer to white light and make it look more natural. Also, by using bluish-green light, a green component is mixed with the overly strong blue light, and the color rendering of blue is lowered.

At this time, considering the visual sensitivity that people perceive green (555 nm) as the brightest, and blue and red are less likely to perceive bright, the one closer to 555 nm is used. Therefore, red light uses light close to orange, and blue-green light uses light close to green.

In this embodiment, based on this technical concept, red light and bluish-green light, which are in complementary colors, are added by selecting wavelengths, thereby maintaining a correlated color temperature of 3,000 K and red color rendering R9 was increased to 93, and blue color rendering properties R6 and R12 could be suppressed.

Further, the red LED 15b5 and the blue-green LED 15b3 are arranged either on the innermost circumference or the outermost circumference, or on both the innermost circumference and the outermost circumference on the surface on which the red LED 15b5 and the blue-green LED 15b3 are arranged.

By arranging the red LED 15b5 and the blue-green LED 15b3 on the outermost peripheral side, more red and blue-green light can be arranged at a position away from the illumination device 1A. Alternatively, by arranging the red LED 15b5 and the blue-green LED 15b3 on the innermost side, more red and blue-green light can be arranged directly below the lighting device 1A. Alternatively, if the red LED 15b5 and the blue-green LED 15b3 are arranged on both the outermost peripheral side and the innermost peripheral side, a large amount of red and blue-green light can be distributed in a well-balanced manner.

As described above, the LED lighting device 1A of the present embodiment controls the daylight color LED 15b1, the light bulb color LED 15b2, the red LED 15b5, and the bluish green LED 15b3, and the daylight color LED 15b1, the light bulb color LED 15b2, the red LED 15b5, and the bluish green LED 15b3. and a control unit 101 for optimizing the light amount ratio of the daylight color LED 15b1 and the light bulb color LED 15b2 by a light control circuit 102 that controls the drive current of the daylight color LED 15b1 and a light control circuit 103 that controls the drive current of the light bulb color LED 15b2. By using the red LED 15b5 and the blue-green LED 15b3 in a quantity of about 2 to 1, the driving can be controlled only by a simple lighting circuit 104 that only turns on and off. is higher than that of a halogen bulb, and it is possible to realize a lighting device that irradiates light that suppresses the color rendering of blue, which is said to attenuate the appetite. Further, by arranging the red LED 15b5 and the blue-green LED 15b3 on the outermost and innermost circumferences, it is possible to realize a wide light distribution while reducing the number of the red LED 15b5 and the blue-green LED 15b3.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

Moreover, the shape of the LED lighting device 1A is not limited to a round shape, and may be other shapes such as a square shape such as a square shape, or a polygonal shape.

Although the outermost and/or innermost LEDs are light bulb color LEDs, daylight color LEDs, red LEDs, and blue-green LEDs, the present invention is not limited to this. For example, the light bulb color LED, the daylight color LED, and the red LED may be arranged on the outermost periphery, and only the light bulb color LED, the daylight color LED, and the blue-green LED may be arranged on the innermost periphery, or only the blue-green color may be arranged on the innermost periphery. An LED and a red LED may be arranged. When arranging LEDs of a plurality of colors, it is desirable to avoid disproportionately arranging LEDs of the same color, and arrange the LEDs of each color at equal intervals as much as possible.

Note that the number of arranged LEDs and the ratio of the numbers are not limited to this, and may be all different numbers, or may be adjusted according to the LEDs to be used and the required characteristics of the lighting device.

DESCRIPTION OF SYMBOLS 1A... LED lighting apparatus (illumination apparatus), 11... Main body base, 11a... Adapter mounting hole, 12... Adapter receiving part (insulating material), 13... Power supply board, 14... Heat sink, 15... LED light source board, 15b... LED Element group 15b1 Daylight color LED 15b2 Light bulb color LED 15b5 Red LED 15b3 Blue green LED 151a, 151b, 151c Luminous flux emitted from LED 152a, 152b, 152c Luminous flux emitted from LED Luminous fluxes 153a, 153b, 153c reflected by the adjacent dome portions, . Dome shape part of LED cover directly above LED, 172a, 172b, 172c... Dome shape part of LED cover closely arranged, 19... Shade, 101... Control part, 102... Dimming (changing the drive current of the daylight color LED) Circuits 103 --- A dimming circuit (which changes the drive current of the bulb-colored LED) 104 --- A lighting circuit (which turns on/off the blue-green LED).

Claims (7)

a daylight-colored LED that emits daylight-colored light;
A bulb-colored LED that emits bulb-colored light,
a red LED that emits red light;
a blue-green LED that emits blue-green light,
The light emitted from the red LED has a peak wavelength within the range of 610 nm to 750 nm,
Light emitted from the blue-green LED has a peak wavelength within a range of 470 nm to 490 nm. 2. The illumination device according to claim 1, wherein the light emitted from said red LED has a peak wavelength within the range of 610 nm to 650 nm. 3. The lighting device according to claim 1, wherein the light emitted from the lighting device is warm color light with a correlated color temperature of 2600K to 3250K. 4. The lighting device according to claim 1, wherein the light emitted from the lighting device has a color rendering index R9 of 75 or higher. 4. The lighting device according to claim 1, wherein the light emitted from the lighting device has a color rendering index R9 of 75 or more, R6 of 75 or less, and R12 of 60 or less. 6. The lighting device according to claim 1, wherein a peak of radiant intensity in a spectral distribution of light emitted from the lighting device has the same light wavelength as a peak of light emitted from the red LED. The red LED and the blue-green LED are arranged either on the innermost circumference or the outermost circumference, or on both the innermost circumference and the outermost circumference on the surface on which the red LED and the blue-green LED are arranged. 7. The lighting device according to any one of claims 1 to 6, wherein the lighting device is

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