WO2018021568A1

WO2018021568A1 - Led light bulb

Info

Publication number: WO2018021568A1
Application number: PCT/JP2017/027563
Authority: WO
Inventors: 圭亮堺; 秋山　貴
Original assignee: シチズン時計株式会社; シチズン電子株式会社
Priority date: 2016-07-28
Filing date: 2017-07-28
Publication date: 2018-02-01
Also published as: JP6899827B2; JPWO2018021568A1

Abstract

The invention provides, as an LED light bulb whereof the light-emission color can be modified by rotating a color disc, a simple-to-use LED light bulb having a simple structure. The LED light bulb comprises a main body, LEDs disposed in the main body, a globe supported by the main body so as to be rotatable and disposed in such a manner as to cover the LEDs, a disc disposed between the globe and the LEDs, and a position modification mechanism changing relatively the positional relationship between the LEDs and the disc concomitantly to a rotation of the globe. In this LED light bulb, the disc contains a first phosphor whereby light emitted from the LEDs is converted into a first light-emission color, and a second phosphor whereby the light emitted from the LEDs is converted into a second light-emitting color that is different from the first light-emitting color, such that a change in the positional relationship by the position modification mechanism causes a third light-emission color, which is emitted from the globe, to change.

Description

LED bulb

The present invention relates to an LED bulb that includes an LED (light emitting diode) and a phosphor that can move with respect to the LED, and that can change the emission color by changing the relative positional relationship between the LED and the phosphor.

An LED serving as a light source and a phosphor that converts the wavelength of all or part of the light emitted from the LED, the phosphor is movable with respect to the LED, and the relative positional relationship between the LED and the phosphor is changed. There is known an illuminating device that can change the emission color.

FIG. 9 of Patent Document 1 shows a white light emitting device in which a wavelength conversion component is rotatable. This white light emitting device includes LEDs arranged around three concentric circles, and a transparent disk (wavelength conversion component) that can rotate around a rotation axis common to the concentric circles. On the surface of the transparent disk, there is formed a wavelength conversion region that includes a phosphor having a predetermined component and concentration and whose wavelength conversion characteristics change according to a given rotation angle. With such a configuration, the white light emitting device can change the color temperature of white light between cold white and warm white by changing the relative positional relationship between the LED and the wavelength conversion region.

Patent Document 2 discloses an illuminating device in which a laminated phosphor sheet having a plurality of regions is provided on an optical path of light emitted from a light source. The illumination device of Patent Document 2 includes a moving unit that moves the relative position between the laminated phosphor sheet and the light source, and can select a region through which light emitted from the light source is transmitted from any of a plurality of regions.

Japanese translation of PCT publication 2010-541283 (FIG. 9, paragraph 0059) JP 2012-221863 A

Patent Document 1 only shows that a transparent disk (hereinafter referred to as a “color disk”) having different wavelength conversion characteristics depending on the location is provided, and the emission color can be adjusted by rotation of the color disk. There is no specific description or suggestion as to how the method described in Patent Document 1 is applied to an LED bulb.

Specifically, Patent Document 2 describes that a laminated phosphor sheet is wound up by a rotary solenoid to move a relative position with a light source. Therefore, the structure of the lighting device described in Patent Document 2 is complicated, and it is difficult to reduce the price and size of the lighting device.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide an LED bulb that has a simple structure and is easy to use, in an LED bulb that can change the emission color by rotating a color disk.

The LED bulb of the present invention includes a main body, an LED disposed in the main body, a globe supported rotatably on the main body and disposed so as to cover the LED, a disk disposed between the globe and the LED, A position changing mechanism that relatively changes the positional relationship between the LED and the disk as the globe rotates. In the LED light bulb of the present invention, the disk has a first phosphor that converts light emitted from the LED into a first emission color, and second emission that differs from the first emission color in the light emitted from the LED. And a second phosphor to be converted into color, and the third emission color emitted from the globe is changed by changing the positional relationship by the position changing mechanism.

In the LED bulb of the present invention, the LED is fixed to the main body, the disk is connected to the glove, the position changing mechanism is a support mechanism that supports the glove so as to be rotatable with respect to the main body, and the disk is a rotation of the glove. It may be configured so as to rotate with the relative position and relatively change the positional relationship with the LED.

The disk of the LED bulb of the present invention may have an annular region, and the first phosphor and the second phosphor may be arranged in the annular region.

The disk of the LED bulb of the present invention may have a recess, and the first phosphor and the second phosphor may be applied to the recess.

The LED light bulb of the present invention has a first phosphor and a second phosphor on a disk so that the ratio of the first phosphor and the second phosphor facing the LED changes as the globe rotates. May be arranged.

The LED bulb of the present invention may further include a first light shielding member disposed around the disk.

The LED bulb of the present invention may further include a second light shielding member disposed between the first phosphor and the second phosphor.

The first light shielding member or the second light shielding member of the LED bulb of the present invention may be a white reflective resin.

The LED of the LED bulb of the present invention may include a dam material, a plurality of LED dies arranged inside the dam material, and a sealing material arranged inside the dam material.

The LED of the LED bulb of the present invention has a plurality of dam materials arranged in a plurality of regions, a plurality of LED dies arranged inside each of the plurality of dam materials, and a plurality of dam materials, respectively. It may contain a sealing material.

The LED bulb of the present invention may further have a mark indicating a third emission color that is changed as the globe rotates.

When the LED of the LED bulb according to the present invention and the disk are in a predetermined positional relationship, the light measured at the position of the target when the third emission color irradiates the target satisfies the following (A). It may be a thing.
(A) The distance D _UVSSL from the black body radiation locus defined by ANSI C78.377 is −0.0325 ≦ D _UVSSL ≦ −0.0075.

When the LED of the LED bulb of the present invention and the disk are in a predetermined positional relationship, when the third emission color irradiates the object, the light measured at the position of the object is further the following (B) And (C) may be satisfied.
(B) CIE 1976 L ^* a ^* b ^* a ^* value in the color space of the following 15 types of modified Munsell color charts of # 01 to # 15 when mathematically assuming illumination by light measured at the position of the object , B ^* values are a ^* n _SSL and b ^* _nSSL (where n is a natural number from 1 to 15, respectively)
CIE 1976 L ^* a of the fifteen kinds of modified Munsell color charts when mathematically assuming illumination with reference light selected according to the correlated color temperature T _SSL (K) of light measured at the position of the object ^{* When the} a ^* value and b ^* value in the b ^* color space are a ^* _nref and b ^* _nref (where n is a natural number from 1 to 15), the saturation difference ΔC _n is −2.7 ≦ ΔC _n ≦ 18.6 (n is a natural number from 1 to 15)
The filling,
The average saturation difference represented by the following formula (1) satisfies the following formula (2),

When the maximum value of the saturation difference is ΔC _max and the minimum value of the saturation difference is ΔC _min , the difference ΔC _max −ΔC _min between the maximum value of the saturation difference and the minimum value of the saturation difference is
3.0 ≦ (ΔC _max −ΔC _min ) ≦ 19.6
Meet.
However, ΔC _n = √ {(a ^* _nSSL ) ² + (b ^* _nSSL ) ² } −√ {(a ^* _nref ) ² + (b ^* _nref ) ² }.
15 types of modified Munsell color chart # 01 7.5 P 4/10
# 02 10 PB 4/10
# 03 5 PB 4/12
# 04 7.5 B 5/10
# 05 10 BG 6/8
# 06 2.5 BG 6/10
# 07 2.5 G 6/12
# 08 7.5 GY 7/10
# 09 2.5 GY 8/10
# 10 5 Y 8.5 / 12
# 11 10 YR 7/12
# 12 5 YR 7/12
# 13 10 R 6/12
# 14 5 R 4/14
# 15 7.5 RP 4/12
(C) The hue angle in the CIE 1976 L ^* a ^* b ^* color space of the above 15 types of modified Munsell color _charts when the illumination by light measured at the position of the object is mathematically assumed is θ _nSSL (degree) ( Where n is a natural number from 1 to 15)
CIE 1976 L ^* a of the fifteen kinds of modified Munsell color charts when mathematically assuming illumination with reference light selected according to the correlated color temperature T _SSL (K) of light measured at the position of the object ^* b ^{* When} the hue angle in the color space is θ _nref (degrees) (where n is a natural number from 1 to 15), the absolute value of the hue angle difference | Δh _n | is 0 ≦ | Δh _n | ≦ 9.0. (Degree) (n is a natural number from 1 to 15)
Meet.
However, Δh _n = θ _nSSL −θ _nref .

The LED bulb of the present invention is an LED bulb capable of changing the emission color depending on the relative positional relationship between the LED and the phosphor, a globe that can rotate around a rotation axis, an LED that is arranged off the rotation axis, And a color disk in which phosphors are separately applied according to a rotation angle around a rotation axis, and the color disk rotates in conjunction with a globe.

In the LED bulb of the present invention, the globe and the colored disk fixed to the globe rotate around the rotation axis. The color disk has a region where phosphors are separately applied according to the rotation angle. This region is laminated to the LED through an air layer. The light emitted from the LED is partly or entirely wavelength-converted by the phosphor when the phosphor is laminated on the upper part, and is emitted from the globe to the outside. When the globe is rotated and the phosphor is disposed on the LED, or the phosphor on the LED is replaced with another phosphor, the emission color of the LED bulb changes.

According to the present invention, it is possible to realize an LED bulb that can change the emission color simply by rotating the globe with a simple structure.

1 is an exploded perspective view of an LED bulb 10 according to a first embodiment of the present invention. FIG. 3 is a partial cross-sectional view of the LED bulb 10. The top view which shows the inside of the globe 11 of the LED bulb 10. FIG. 1 is a perspective view of a phosphor frame 12 included in an LED bulb 10. FIG. The side view of LED16 contained in the LED bulb 10. FIG. FIG. 4 is a lateral cross-sectional view of the LED 16 included in the LED bulb 10. The perspective view of the reflective frame 13 contained in the LED bulb 10. FIG. The perspective view which shows the relationship between the reflective frame 13 contained in LED bulb 10, and LED16. FIG. 3 is an enlarged perspective view showing a relationship between a globe 11 and a phosphor frame 12 included in the LED bulb 10. FIG. 3 is a top view of a case 18 included in the LED bulb 10. The cross-sectional enlarged view of the connection location of the globe 11 and the case 18 included in the LED bulb 10. FIG. 3 is an external view of a connection portion between a globe 11 and a case 18 included in the LED bulb 10. Sectional drawing of the diameter direction of the fluorescent substance flame | frame 22 contained in the LED bulb 20 of 2nd Embodiment of this invention. Sectional drawing of the circumferential direction of the fluorescent substance flame | frame 22 contained in the LED bulb 20 of 2nd Embodiment of this invention. Sectional drawing which shows the structure of LED36 contained in the LED bulb 30 of 3rd Embodiment of this invention. The figure which shows the area | region on the circuit board 35 in which LED36 is arrange | positioned. The figure which shows the example of arrangement | positioning of the fluorescent substance in the disk part 32f of the fluorescent substance flame | frame corresponding to the circuit board. The top view of the circuit board 45 contained in the LED bulb 40 of 4th Embodiment of this invention. The top view of the circuit board 55 contained in the LED bulb 50 of 5th Embodiment of this invention. The top view of the fluorescent substance flame | frame 62 contained in the LED bulb 60 of 6th Embodiment of this invention.

Hereinafter, preferred embodiments of the LED bulb will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted. Moreover, the scale of the member is appropriately changed for the sake of explanation.

(First embodiment)
FIG. 1 is an exploded perspective view of an LED bulb 10 according to a first embodiment of the present invention. The globe 11 is attached with a phosphor frame 12 (color disk) that is separately coated with phosphors having different characteristics. The phosphor frame 12 is fixed to the globe 11 via the bridge portion 12a. The reflection frame 13 and the circuit board 15 are fixed to the heat sink 18 a with screws 14. The heat sink 18 a is fixed to the case 18 so that the upper surface is disposed on the upper part of the case 18. The base 19 is attached to the lower part of the case 18. The LED 16 and the connector 17 are mounted on the upper surface of the circuit board 15. The globe 11 is fitted into the case 18 that is the main body of the LED bulb 10 so that the globe 11 can rotate around the rotation axis A that is the center line of the globe 11 and the case 18. Thus, the phosphor frame 12 is disposed between the globe 11 and the LED 16.

FIG. 2 is a partial cross-sectional view of the LED bulb 10 and shows a part of a cross section including the central LED 16 among the three LEDs 16 (see FIG. 1) aligned on the short side of the circuit board 15. As described above, the heat sink 18a is disposed on the upper portion of the case 18, and the circuit board 15 is laminated on the upper surface thereof. On the circuit board 15, LEDs 16 are mounted at both ends, and a reflection frame 13 is laminated. The reflection frame 13 is fixed to the circuit board 15 with screws 14.

The globe 11 is in contact with the upper end of the case 18 at the step portion 11b. The glove 11 is supported in a rotatable state with respect to the case 18 by engagement of locking claws (described later) formed on the lower part of the glove 11 and the upper part of the case 18. The globe 11 and the phosphor frame 12 are connected by bonding the step portion 11 b of the globe 11 and the bridge portion 12 a of the phosphor frame 12.

The phosphor frame 12 includes an annular portion 12f and a bridge portion 12a, and the center of the annular portion 12f is open. Further, the phosphor frame 12 has a recess 12b formed immediately above the LED 16.

FIG. 3 is a plan view showing the inside of the globe 11 of the LED bulb 10 and shows a state in which the globe 11 is cut in the horizontal direction along the BB cutting line of FIG. 2 and the LED bulb 10 is viewed from above. . As shown in FIG. 3, a cut surface 11 a and a stepped portion 11 b are observed on the globe 11. The step portion 11 b of the globe 11 and the bridge portion 12 a of the phosphor frame 12 are bonded and fixed so that the phosphor frame 12 rotates in conjunction with the globe 11.

The phosphor frame 12 is made of transparent plastic. The annular portion of the phosphor frame 12 is divided into eight

regions

12b, 12b, 12c, 12c, 12d, 12d, 12e, and 12e. The

regions

12b and 12b, the

regions

12c and 12c, the

regions

12d and 12d, and the

regions

12e and 12e are arranged at positions that make a pair with the center of the ring. The

regions

12c, 12c, 12d, 12d, 12e, and 12e are coated with a phosphor. Hereinafter, the

regions

12c, 12d, and 12e are also referred to as

phosphors

12c, 12d, and 12e. The

regions

12b and 12b are not coated with a phosphor and are formed as recesses. Hereinafter, the regions 12b are also referred to as recesses 12b. The LED 16 is observed through the

regions

12b and 12b. When the LED 16 is turned on in the state of FIG. 3, the LED bulb 10 emits light in the emission color of the LED 16.

The reflection frame 13 is observed under the phosphor frame 12. Since the phosphor frame 12 is transparent, a part of the reflection frame 13 can be observed through the phosphor frame 12, but this portion is not shown. A circuit board 15 is observed under the reflection frame 13. The reflection frame 13 is fixed to the circuit board 15 with screws 14 at a position deviating from the rotation axis A. A connector 17 is mounted on the upper surface of the circuit board 15 at a position that does not interfere with the reflection frame 13. Under the circuit board 15, the upper surface of the heat sink 18a is observed.

FIG. 4 is a perspective view of the phosphor frame 12 included in the LED bulb 10, and shows a state in which the phosphor frame 12 before being coated with the

phosphors

12c, 12d, and 12e is viewed from the lower side. As shown in FIG. 4, the phosphor frame 12 includes an annular portion 12f and two bridge portions 12a protruding from the annular portion 12f. The annular portion 12f has an opening diameter of 20 mm and an outer diameter of 30 mm. On the lower surface of the annular portion 12f, eight

concave portions

12b, 12b, 12c ′, 12c ′, 12d ′, corresponding to the eight

regions

12b, 12b, 12c, 12c, 12d, 12d, 12e, 12e, 12d ', 12e', and 12e 'are formed. As described above, the

phosphors

12c, 12d, and 12e are applied to the recesses 12c ′, 12d ′, and 12e ′ other than the recess 12b, respectively. The bridge portion 12a is provided with a step toward the lower side.

As described above, in the phosphor frame 12, the

phosphors

12c, 12d, and 12e are separately applied to the annular region according to the rotation angle around the rotation axis, and the center portion is open. With such a configuration, the LED bulb 10 of the present embodiment can reduce the usage amount of the

phosphors

12c, 12d, and 12e and reduce the weight of the phosphor frame 12. Further, as described above, since the LED bulb 10 is lit with the emission color of the LED 16, the phosphor is not applied to the recess 12b and remains transparent.

FIG. 5A is a side view of the LED 16 included in the LED bulb 10. As shown in FIG. 5A, when the LED 16 is viewed from the side, the sealing material 16a and the substrate 16b in contact with the lower portion of the sealing material 16a are observed. FIG. 5B is a cross-sectional view of the LED 16 as viewed from the side. The sealing material 16a is made of a transparent resin, and as shown in FIG. 5B, the LED die 16c is sealed, and has a convex lens portion with a diameter of 2.2 mm and a raised central portion. In FIG. 5B, the substrate 16b has an electrode 16b1, an insulator 16b2, and an electrode 16b3, and the LED die 16c is connected to the electrode 16b1 and the electrode 16b3 by a wire 16d. The substrate 16b is a square having a planar shape of 2.57 mm × 2.57 mm, a thickness of about 0.1 mm, and a connection electrode is formed on the lower surface. The height from the bottom surface of the substrate 16b to the top of the sealing material 16a is 1.14 mm.

FIG. 6 is a perspective view of the reflection frame 13 included in the LED bulb 10. The reflection frame 13 includes a reflection portion 13a, an arm portion 13b, and an attachment portion 13c. The reflection frame 13 is made of white plastic, and is configured such that the inclined surface inside the reflection portion 13 a reflects the emitted light of the LED 16. Further, the upper surfaces of the reflecting portion 13a, the arm portion 13b, and the mounting portion 13c are flush with each other, and the arm portion 13b is slightly thinner than the other portions.

FIG. 7 is a perspective view showing the relationship between the reflective frame 13 and the LED 16 included in the LED bulb 10. Three LEDs 16 are arranged so as to be exposed from the bottom inside the reflecting portion 13a. The reflection part 13a is arrange | positioned so that LED16 may be pinched | interposed from right and left in FIG. There is a height difference of about 2 mm between the upper surface of the LED 16 and the upper surface of the reflection frame 13.

The LED 16 is a blue light-emitting diode, and the wavelength of light emitted from the LED 16 is approximately 450 to 460 nm and has a spectrum having a sharp peak. In the state shown in FIG. 3, the light emitted from the LED 16 passes through the phosphor frame 12 and reaches the globe 11. As a result, the LED bulb 10 emits blue light.

When the globe 11 is rotated 45 ° counterclockwise from the state shown in FIG. 3, the phosphor 12 c covers the upper part of the LED 16. The phosphor 12c is a phosphor that contains YAG (Yttrium Aluminum Garnet) as a fluorescent material and emits yellow light. The phosphor 12c is configured to wavelength-convert part of the light emitted from the LED 16 to yellow light. The yellow light whose wavelength has been converted by the phosphor 12c and the blue light whose wavelength has not been converted reach the globe 11, and the LED bulb 10 emits white light.

When the globe 11 is further rotated 45 ° counterclockwise, the phosphor 12d covers the top of the LED 16. The phosphor 12d is a phosphor that contains CaAlSiN3 or the like as a phosphor and emits red light. The phosphor 12d is configured to wavelength-convert light emitted from all LEDs 16 to red light. As a result, the LED bulb 10 emits red light.

When the globe 11 is further rotated 45 ° counterclockwise, the phosphor 12e covers the upper part of the LED 16. The phosphor 12e is a phosphor that contains β-SiAlON or the like as a phosphor and emits green light. The phosphor 12e is configured to convert the wavelength of all LEDs 16 to green light. As a result, the LED bulb 10 emits green light.

As described above, in the LED bulb 10, the relative positional relationship between the LED 16 and the phosphor is changed with the rotation of the globe 11 around the rotation axis, and the emission colors thereof are blue, white, red, and green. Change. The LED bulb 10 of the present embodiment is obtained by adding a phosphor frame 12 that allows the globe 11 to rotate and is fixed to the globe 11 with respect to a normal LED bulb. Since the temperature rise of the globe 11 of the LED bulb 10 is small, the user will not burn his / her hand even if he / she touches the globe 11 to rotate the globe 11. That is, the LED bulb 10 has an effect that the function of changing the emission color by rotating the phosphor frame 12 (color disk) is realized with a simple structure, and has an effect that the user can easily use it.

A light shielding member may be provided around the phosphor frame 12. For example, in the state where the phosphor frame 12 is rotated 45 ° counterclockwise from the state of FIG. 3, the light emission of the LED 16 is wavelength-converted by the fluorescent material contained in the phosphor 12c, and isotropically centered on the fluorescent material. Radiated. For this reason, the wavelength-converted light is also emitted from the lateral direction of the phosphor frame 12 (the direction parallel to the paper surface in FIG. 3). The wavelength-converted light emitted in the lateral direction may disturb the light distribution characteristics of the LED bulb 10. If a light shielding member is provided around the phosphor frame 12, light emitted in the lateral direction of the phosphor frame 12 is eliminated. As a result, the light distribution characteristics of the LED bulb 10 are not disturbed. Similarly, a light shielding member may be disposed on the inner side surface of the phosphor frame 12.

Further preferably, the light shielding member is a white reflective resin. When a light-shielding member made of white reflective resin is provided around the phosphor frame 12, light emitted in the lateral direction of the phosphor frame 12 is irregularly reflected by the white reflective resin. As a result, the luminous efficiency of the LED bulb 10 is improved. The same applies to the inner side surface of the phosphor frame 12.

In the LED bulb 10,

concave portions

12b, 12c ′, 12d ′, and 12e ′ are provided on the lower surface of the phosphor frame 12, and the

fluorescent materials

12c, 12d, and 12e are applied to the concave portions 12c ′, 12d ′, and 12e ′. On the other hand, phosphors may be applied separately on a flat surface of a color disk (or phosphor frame) having no recesses by a well-known method. However, if the

concave portions

12b, 12c ′, 12d ′, and 12e ′ are provided in the color disk (phosphor frame 12) like the LED bulb 10, the phosphor can be applied with a medium having a low viscosity, and the manufacture is easy. become. Further, the flat surface of the color disk (or phosphor frame) having no recess may be partitioned by a dam material, and a phosphor having a low viscosity may be applied to the partitioned region. However, if the

recesses

12b, 12c ′, 12d ′, and 12e ′ are provided like the LED bulb 10, the step of applying the dam material can be omitted.

In the LED bulb 10, the emission colors are white, red, green, and blue, but any emission color can be obtained by adjusting the phosphor material and the composition of the phosphor contained in the phosphor. Further, in the LED bulb 10, the LED 16 is disposed so as to be opposed to the rotation axis A so as to be ½ rotationally symmetric, but the LED 16 may be disposed so as to be 1 / n rotationally symmetric. Further, in the LED bulb 10, the

phosphors

12c, 12d, and 12e applied to the phosphor frame 12 are configured so that the light emission of the paired LEDs 16 is wavelength-converted to the same color. On the other hand, you may comprise a fluorescent substance so that the wavelength of light emission of LED16 used as a pair may be wavelength-converted. In addition, the phosphor frame 12 of the LED bulb 10 is configured to have an annular portion 12f having an outer periphery and an opening, and

phosphors

12c, 12d, and 12e are applied to a partial region of the annular portion 12f. . However, the phosphor frame 12 may be configured to have a disk portion that does not have an opening, and the phosphor may be applied to a fan-shaped region obtained by dividing the disk portion by a radius. In this case, since more LEDs can be stacked with the phosphor, the amount of light can be increased. In the LED bulb 10, the LED 16 is a blue light emitting diode. However, the LED is not limited to a blue light emitting diode, and may be a near ultraviolet light emitting LED or a white LED.

The connection between the globe 11 and the phosphor frame 12 will be described with reference to FIG. FIG. 8 is an enlarged perspective view showing the relationship between the globe 11 and the phosphor frame 12 included in the LED bulb 10, and more specifically, the globe 11 with the globe 11 and the phosphor frame 12 connected to each other. FIG. As will be described later, the phosphor frame 12 includes an annular portion 12f and two bridge portions 12a that protrude oppositely from the annular portion 12f. The bridge portion 12a is provided with a step 12g directed downward. Further, the step 11b of the globe 11 is formed with a notch 11c that can accommodate the step 12g of the bridge 12a. The bottom surface of the notch 11c of the globe 11 and the top surface of the step 12g of the phosphor frame 12 are connected by adhesion.

The relationship between the globe 11 and the case 18 will be described with reference to FIGS. 9A to 9C. FIG. 9A is a top view of the case 18 included in the LED bulb 10. FIG. 9B is an enlarged cross-sectional view of a connection portion between the globe 11 and the case 18 included in the LED bulb 10, and shows a cross section taken along the line CC in FIG. FIG. 9C is an external view of a connection portion between the globe 11 and the case 18 included in the LED bulb 10.

As shown in FIG. 9A, locking claws 18b are formed in the vicinity of the outer periphery of the upper portion of the case 18. The claw 18b can be formed of an elastic material, for example, resin or metal. In FIG. 9A, two claws 18b are formed at four places, but this is not a limitation.

As shown in FIG. 9B, a protruding portion 11 c is formed at the tip of the stepped portion 11 b of the globe 11. The globe 11 and the case 18 are connected by engaging the protruding portion 11 c of the globe 11 and the claw 18 b of the case 18. The bottom surface of the stepped portion 11b of the globe 11 and the top surface of the claw 18b of the case 18 are formed in substantially the same circular shape when viewed from above, and the globe 11 can rotate with respect to the case 18 around the rotation axis. When the globe 11 is rotated, since the globe 11 and the phosphor frame 12 are connected as described above, the phosphor frame 12 also rotates about the rotation axis. As a result, as the globe 11 rotates, the positional relationship between the LED 16 and the phosphor frame 12 is relatively changed.

When the protrusion 11c is continuously formed on the circumference of the step portion 11b, even when the claw 18b is formed only on a part of the upper portion of the case 18, the glove 11 is rotated. The connection between the globe 11 and the case 18 can be stably maintained. On the contrary, the protrusion 11c may be formed only in part and the claw 18b may be formed continuously.

The globe 11 and the case 18 may be provided with a protruding portion and a locking portion, respectively, to restrict the globe 11 from rotating beyond a predetermined angle with respect to the case 18. For example, the protrusion provided in the globe 11 is restricted by a plurality of engaging portions provided in the case 18 and can be prevented from rotating beyond the engaging portion. In an LED bulb in which the emission color periodically changes every rotation by a predetermined angle (180 degrees in the first embodiment), if the glove does not rotate beyond a predetermined angle, the user The variable range can be grasped clearly.

As shown in FIG. 9C, a scale 11 d is formed on the outer surface of the lower end of the globe 11, and an indicator 18 c is formed on the outer surface of the upper end of the case 18. The state of FIG. 9C indicates that the emission color of the LED bulb 10 is a color (in this case, B: blue) represented by the scale 11d at the position of the index 18c. With this configuration, the user can easily know the emission color of the LED bulb 10 corresponding to the rotation angle of the globe 11 without actually lighting the LED bulb 10. In FIG. 9C, the scale 11d is formed on the globe 11 and the indicator 18c is formed on the case 18 to form a mark indicating the emission color. However, the present invention is not limited to this configuration. A scale may be formed on the surface. In FIG. 9C, the light emission color is represented by characters on the scale 11d. However, the present invention is not limited to this configuration, and is based on the color corresponding to the light emission color, the numerical value corresponding to the ratio of irradiation to the LED 16 for each phosphor, and the like. May be represented.

Further, the LED bulb 10 may include a click mechanism that gives a click feeling to the user when the rotation angle of the globe 11 around the rotation axis A is a predetermined angle. For example, if it is configured to give a click feeling at a rotation angle at which a standard emission color is obtained, the user can easily cause the LED bulb 10 to emit light in the standard emission color.

(Second Embodiment)
The LED bulb 20 of the second embodiment of the present invention is different from the LED bulb 10 of the first embodiment in that it includes a phosphor frame 22 having a light shielding member. The same members as those of the LED bulb 10 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

FIG. 10A is a sectional view in the diameter direction of the phosphor frame 22 included in the LED bulb 20 of the second embodiment of the present invention, and FIG. 10B is a sectional view in the circumferential direction of the phosphor frame 22.

The phosphor frame 22 of the present embodiment is configured such that the annular portion 22f includes a light shielding member 22f1 and a transparent member 22f2. As shown in FIG. 10A, the light shielding member 22f1 is provided around the phosphor frame 22 by a member that blocks light. The light shielding member 22f1 may be provided on the inner side surface of the phosphor frame 22. The upper surface of the annular portion 22f is formed of a transparent member 22f2, and transmits light emitted from the LED 16 and / or wavelength-converted light.

As shown in FIG. 10B, a light shielding member 22f3 may be provided so as to partition the phosphors that have been separately coated (for example, between the phosphor 22d and the phosphor 22e). By providing the light shielding member 22f1 or the light shielding member 22f3 as shown in FIG. 10A or FIG. 10B, the light whose wavelength is converted by the phosphor 22d is not radiated in the lateral direction, but is radiated to the globe 11 through the transparent member 22f2. With this configuration, the light distribution characteristics of the LED bulb 20 can be stabilized.

As described above, the light shielding member 22f1 or the light shielding member 22f3 can be made of a white reflective resin. The light emitted in the lateral direction is irregularly reflected by the light shielding member 22f1 or the light shielding member 22f3 made of white reflective resin, and the luminous efficiency of the LED bulb 20 is improved. Such a phosphor frame including the light shielding member 22f1, the light shielding member 22f3, and the transparent member 22f2 can be manufactured by a two-color injection molding method.

In both the first embodiment and the second embodiment, the annular portion of the phosphor frame is arranged so that the phosphor applied on the transparent member faces the LED. As a result, the light emitted from the LED first enters the phosphor and reaches the globe via the transparent member. However, it is not intended to limit to this configuration, and the order of the transparent member and the phosphor may be reversed. Specifically, the concave portion may be formed on the upper surface of the annular portion, the bottom of the concave portion may be formed of a transparent member, and the phosphor may be applied to the concave portion.

(Third embodiment)
The LED bulb 30 of the third embodiment of the present invention is different from the LED bulb 10 of the first embodiment in that the LED is a CSP (chip size package). The same members as those of the LED bulb 10 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In the LED 16 used in the LED bulb of the first embodiment, as shown in FIG. 5B, an LED die 16c having a width of 1.0 mm or less is mounted on a substrate 16b having a side of 2.57 mm. In order to obtain a bright LED bulb, even if an attempt is made to increase the ratio of the area of the LED die 16c to the mounting area of the circuit board 15, it is difficult to realize using the LED 16.

In the LED bulb 30 of the third embodiment, a CSP LED 36 is used. FIG. 11 is a cross-sectional view showing the structure of the LED 36 included in the LED bulb 30 according to the third embodiment of the present invention. Referring to FIG. 11, an LED 36 that is a CSP includes an LED die 36c, a frame 36d, and a sealing material 36a.

The LED die 36c is a semiconductor element that emits light, and is configured by laminating a sapphire substrate 36c1, a semiconductor layer 36c2, and an electrode 36c3. A semiconductor layer 36c2 including a light emitting layer is formed on the sapphire substrate 36c1. Further, an electrode 36c3 used for connection to the circuit board 15 is formed on the surface of the semiconductor layer 36c2 that faces the surface on which the sapphire substrate 36c1 is formed.

The frame 36d is provided on the outer periphery of the LED die 36c, regulates the shape of the sealing material 36a, which is a transparent resin that seals the LED die 36c, and flows out the light emitted from the LED die 36c in the lateral direction. Shut off. When the frame 36d is formed of a white reflective resin, light emitted in the lateral direction is irregularly reflected and the light emission efficiency of the LED bulb 30 is improved, which is preferable.

In the LED 36 shown in FIG. 11, the width of the outer shape of the frame 36d is 1.1 mm or less, and the width of the LED die 36c is 0.8 mm. The height of the frame 36d is 0.4 mm or less, and the combined height of the sapphire substrate 36c1 and the semiconductor layer 36c2 in the LED die 36c is 0.1 mm or less. Thus, in the CSP LED 36, the LED 36 and the LED die 36c are substantially the same size. Therefore, more LED dies can be arranged in a region of the same area on the circuit board, and a brighter LED bulb 30 can be obtained. The size of the LED 36 described above is an example, and the present invention is not limited to this.

When the area where the CSP LEDs 36 are arranged on the circuit board is enlarged, it becomes possible to arrange more LED dies. FIG. 12 is a diagram showing a region on the circuit board 35 where the LEDs 36 are arranged. As shown in FIG. 12, the CSP LEDs 36 are arranged in two fan-shaped regions having a predetermined central angle in a circular circuit board 35. The fan-shaped region does not include the center of the circuit board 35 having a circular shape. As a result, the LED 36 is arranged away from the center of the circuit board 35, that is, the rotational axis A of the globe 11. The two fan-shaped regions have a relationship of overlapping when rotated 180 degrees. The LEDs 16 of the LED bulb 10 of the first embodiment are arranged one-dimensionally on a circle having a predetermined radius on the circuit board 15. On the other hand, the LEDs 36 of the LED bulb 30 of the third embodiment are two-dimensionally arranged in the fan-shaped region on the circuit board 35. Therefore, more LED dies can be arranged on the circuit board 35 than the circuit board 15 having the same area. Needless to say, an LED that is not a CSP may be arranged in the fan-shaped region shown in FIG.

FIG. 13 is a diagram showing an arrangement example of the phosphors in the disk portion 32f of the phosphor frame corresponding to the circuit board 35. In order to correspond to the LED 36 arranged from the vicinity of the center to the vicinity of the outer edge of the circuit board 35, the

concave portions

32b, 32c ′, 32d ′, and 32e ′ of the disk portion 32f are not in an annular shape as in the first embodiment, but in a fan shape. It is formed into a shape. The

phosphors

32c, 32d and 32e are applied in this fan shape.

In the example of FIG. 13, eight fan shapes having a central angle of 45 degrees are formed, and the corresponding phosphors are applied or not applied and remain transparent. According to the phosphor frame having such a disk portion 32f, the light emission color of the LED bulb 30 is switched every time the globe 11 is rotated 45 degrees. The application region of the phosphor is an example, and the number of divisions and the shape can be changed as appropriate.

(Fourth embodiment)
The LED light bulb 40 according to the fourth embodiment of the present invention includes the LED 46 having a structure in which an LED die mounted in a region surrounded by a dam material in the circuit board 45 is sealed with a resin. Different from the LED bulb 10.

FIG. 14 is a top view of the circuit board 45 included in the LED bulb 40 of the fourth embodiment of the present invention. Referring to FIG. 14, the LED 46 mounted on the circuit board 45 has an LED die 46a and a dam material 46b. The LED die 46a is configured in the same manner as the LED die 36c in the third embodiment, and a plurality of LED dies 46a are arranged in a plurality of regions on the circuit board 45 surrounded by a dam material 46b described later.

A plurality of dam members 46b are provided so as to surround a predetermined region on the circuit board 45, and regulate the shape of the sealing material which is a transparent resin for sealing the LED die 46a and light emitted from the LED die 46a. Block the lateral flow of When the dam material 46b is formed of a white reflective resin, light emitted in the lateral direction is irregularly reflected and the light emission efficiency of the LED bulb 40 is improved, which is preferable.

As described above, the LED 46 used in the LED bulb 40 includes a plurality of dam materials 46b arranged in a plurality of regions, a plurality of LED dies 46a arranged inside the plurality of dam materials 46b, and a plurality of dies. And a sealing material disposed inside the dam material 46a.

By configuring the circuit board 45 and the LEDs 46 in this manner, more LED dies can be arranged on the circuit board having the same area. Moreover, since the LED die can be sealed in a single process, the manufacturing process can be further simplified as a whole.

In FIG. 14, since the predetermined area surrounded by the dam material 46b is fan-shaped, a phosphor frame having a disk portion in which the phosphor is applied to the fan-shaped area, such as the disk portion 32f of the phosphor frame shown in FIG. It is preferred to use. In addition, the predetermined area | region which the dam material 46b surrounds is not limited to a fan shape, For example, it can change suitably to the rod-shaped shape etc. which extend in a radial direction. At this time, the shape of the region where the phosphor is applied to the phosphor frame may be appropriately changed so as to match the shape of the predetermined region surrounded by the dam material 46b.

(Fifth embodiment)
In an LED bulb 50 according to a fifth embodiment of the present invention, an LED 46 having a structure in which an LED die mounted in a region surrounded by a dam material is sealed with a resin is disposed on a circuit board 55 via a submount circuit board. This is different from the LED bulb 40 of the fourth embodiment.

FIG. 15 is a top view of the circuit board 55 included in the LED bulb 50 according to the fifth embodiment of the present invention. Referring to FIG. 15, the LED 56 mounted on the circuit board 55 includes an LED die 56a, a dam material 56b, and a submount circuit board 56c. The LED die 56a and the dam material 56b are the same as the LED die 46a and the dam material 46b in the fourth embodiment except that they are mounted not on the circuit board 55 but on the submount circuit board 56c. Description is omitted.

The submount circuit board 56c is a so-called COB (chip on board) package in which the LED die 56a and the dam material 56b are mounted. The submount circuit board 56 c in which the LED die 56 a and the dam material 56 b are mounted is disposed on the circuit board 55 as the LED 56. Accordingly, the LED 56 is mounted on the LED bulb 50 via the submount circuit board 56c.

As described above, the LED 56 used in the LED bulb 50 includes a plurality of dam materials 56b arranged in a plurality of regions, a plurality of LED dies 56a arranged inside the plurality of dam materials 56b, and a plurality of dies. And a sealing material disposed inside the dam material 56a.

The shape of the region surrounded by the dam material 56b and the shape of the region where the phosphor is applied to the phosphor frame are the same as in the fourth embodiment. The submount circuit board 56c is formed in a shape in which one side of the rectangle is an arc, but is not limited to this shape and can be changed as appropriate.

(Sixth embodiment)
The LED bulb 60 of the sixth embodiment of the present invention is different from the LED bulb 10 of the first embodiment in that it has a phosphor frame 62 that is separately coated with two phosphors.

FIG. 16 is a top view of the phosphor frame 62 included in the LED bulb 60 according to the sixth embodiment of the present invention. In FIG. 16, the bridge portion of the phosphor frame 62 is omitted. Referring to FIG. 16, the circular phosphor frame 62 is equally divided by its diameter and further divided to be rotationally symmetric by a curve passing through the center of the circle. Within each divided area, the

phosphor

62b and 62c is applied. The phosphor frame 62 may have the light shielding member described in the second embodiment so that the phosphor frame 62 is partitioned around the phosphor frame 62 and / or so as to partition the separately painted phosphors.

The phosphor frame 62 may be used with any LED arranged, but since the phosphor is applied to the vicinity of the center, it is more preferable that the LED is arranged to the vicinity of the center. Here, it demonstrates below that the LED light bulb 60 has the circuit board 35 shown in FIG.

When the phosphor frame 62 overlaps the circuit board 35 at the angle shown in FIG. 16, the LED 36 and the phosphor 62b face each other. At this time, the LED bulb 60 emits light in the first color. As the phosphor frame 62 is rotated to the left together with the globe 11 from this state, the area of the phosphor 62b facing the LED 36 decreases and the area of the phosphor 62c increases. When a predetermined angle (135 degrees to the left in the present embodiment) is rotated, the LED 36 and the phosphor 62c transition to a state where they face each other. At this time, the LED bulb 60 emits light in the second color.

Thus, in the LED bulb 60, the phosphor is applied to the phosphor frame 62 so that the ratio of the phosphor facing the LED 36 changes as the globe 11 rotates. With this configuration, the user can adjust the emission color of the LED bulb 60 according to the usage environment and preferences, which is preferable.

In the present embodiment, the phosphor 62b is a black body on the CIE1960 (u, v) chromaticity diagram, rather than the color emitted by the LED bulb 60 when the phosphor 62c faces the LED 36 when facing the LED 36. D _uv which is the distance from the radiation locus is set to emit light with a small color. The phosphor 62b may be set to emit light from the LED bulb 60 with a color that approximates a black body radiation locus, and the phosphor 62c may be a color that can be clearly recognized even when it is dark. The LED bulb 60 having such a phosphor frame 62 is suitable for use in a place where a situation where normal brightness is required and a situation where the color is desired to be clearly confirmed are mixed in time series. Such a place is, for example, a living room at home, and it is conceivable to switch between lighting at normal time and lighting at meal time.

The color approximated to the black body radiation locus is, for example, a color having D _uv of 0.02 or less. Among the colors that approximate the black body radiation locus, the color with a correlated color temperature of 5700K to 7100K, especially about 6500K, is called a daylight color. Since the daylight color is close to the color of the cloudy sky, it is suitable for lighting in a refreshing and refreshing atmosphere.

As an example of the color emitted by the LED bulb 60 when the LED 36 and the phosphor 62c face each other, when the emission color of the LED bulb 60 irradiates the target, the light measured at the position of the target is (A Colors that meet) can be used:
A) The distance D _UVSSL from the black body radiation locus defined by ANSI C78.377 is −0.0325 ≦ D _UVSSL ≦ −0.0075.

In addition, as an example of the color emitted by the LED bulb 60 when the LED 36 and the phosphor 62c face each other, the light measured at the position of the target when the emission color of the LED bulb 60 irradiates the target is the above-mentioned In addition to (A), colors that satisfy the following (B) and (C) can be used:
(B) CIE 1976 L ^* a ^* b ^* a ^* in the color space of the following 15 types of modified Munsell color charts of # 01 to # 15 when the illumination by the light measured at the position of the object is mathematically assumed And b ^* values are a ^* n _SSL and b ^* _nSSL (where n is a natural number from 1 to 15),
CIE 1976 L ^{* of the} 15 types of corrected Munsell color charts when mathematically assuming illumination with reference light selected according to the correlated color temperature T _SSL (K) of light measured at the position of the object ^. a ^{^{^*}} b ^* a ^* values in a color space, b ^* values of each a ^{^*} _{_nref,} b ^* _nref (where n is from 1 natural numbers 15) when the degree of saturation difference [Delta] C _n is -2.7 ≦ [Delta] C _n ≦ 18.6 (n is a natural number from 1 to 15)
The filling,
The average saturation difference represented by the following formula (1) satisfies the following formula (2),

When the maximum value of the saturation difference is ΔC _max and the minimum value of the saturation difference is ΔC _min , the difference ΔC _max −ΔC _min between the maximum value of the saturation difference and the minimum value of the saturation difference is
3.0 ≦ (ΔC _max −ΔC _min ) ≦ 19.6
Meet.
However, ΔCn = √ {(a ^* _nSSL ) ² + (b ^* _nSSL ) ² } −√ {(a ^* _nref ) ² + (b ^* _nref ) ² }.
15 types of modified Munsell color chart # 01 7.5 P 4/10
# 02 10 PB 4/10
# 03 5 PB 4/12
# 04 7.5 B 5/10
# 05 10 BG 6/8
# 06 2.5 BG 6/10
# 07 2.5 G 6/12
# 08 7.5 GY 7/10
# 09 2.5 GY 8/10
# 10 5 Y 8.5 / 12
# 11 10 YR 7/12
# 12 5 YR 7/12
# 13 10 R 6/12
# 14 5 R 4/14
# 15 7.5 RP 4/12
(C) The hue angle in the CIE 1976 L ^* a ^* b ^* color space of the above 15 types of modified Munsell color _charts when the illumination by light measured at the position of the object is mathematically assumed is θ _nSSL (degrees) (Where n is a natural number from 1 to 15)
CIE 1976 L ^{* of the} 15 types of corrected Munsell color charts when mathematically assuming illumination with reference light selected according to the correlated color temperature T _SSL (K) of light measured at the position of the object ^. When the hue angle in the a ^* b ^* color space is θ _nref (degrees) (where n is a natural number from 1 to 15), the absolute value of the hue angle difference | Δh _n | is 0 ≦ | Δh _n | ≦ 9. 0 (degrees) (n is a natural number from 1 to 15)
Meet.
However, Δh _n = θ _nSSL −θ _nref .

It should be noted that the

phosphors

62b and 62c may be configured to emit light in colors other than light emission, such as a light bulb color and daylight white, in a color that approximates a black body radiation locus or a color that is clearly recognizable even in the dark. Good. In the sixth embodiment, the phosphor frame 62 may be painted with three or more phosphors.

Claims

An LED bulb,
The body,
An LED disposed on the body;
A glove that is rotatably supported by the main body and arranged to cover the LED;
A disk disposed between the globe and the LED;
A position changing mechanism that relatively changes the positional relationship between the LED and the disk as the globe rotates,
The disk converts a first phosphor that converts light emitted from the LED into a first emission color, and converts a light emitted from the LED into a second emission color different from the first emission color. A second phosphor that
By changing the positional relationship by the position changing mechanism, the third emission color emitted from the globe changes.
LED bulb characterized by that.
The LED is fixed to the main body,
The disk is connected to the globe,
The position changing mechanism is a support mechanism that rotatably supports the globe with respect to the main body,
The disk rotates with the rotation of the globe and relatively changes the positional relationship with the LED,
The LED bulb according to claim 1.
The LED bulb according to claim 1 or 2, wherein the disk has an annular region, and the first phosphor and the second phosphor are arranged in the annular region.
4. The LED bulb according to claim 1, wherein the disk has a recess, and the first phosphor and the second phosphor are applied to the recess.
As the globe rotates, the first phosphor and the second phosphor on the disk so that the ratio between the first phosphor and the second phosphor facing the LED changes. The LED bulb according to any one of claims 1 to 4, wherein is disposed.
The LED bulb according to any one of claims 1 to 5, further comprising a first light-shielding member disposed around the disk.
The LED bulb according to any one of claims 1 to 6, further comprising a second light-shielding member disposed between the first phosphor and the second phosphor.
The LED light bulb according to claim 6 or 7, wherein the first light shielding member or the second light shielding member is a white reflective resin.
The LED includes a dam material, a plurality of LED dies disposed inside the dam material, and a sealing material disposed inside the dam material. LED bulb.
The LED includes a plurality of dam materials respectively disposed in a plurality of regions, a plurality of LED dies disposed inside the plurality of dam materials, and a sealing disposed respectively inside the plurality of dam materials. The LED bulb according to any one of claims 1 to 8, comprising a material.
The LED bulb according to any one of claims 1 to 10, further comprising a mark indicating the third emission color that is changed in accordance with rotation of the globe.
The LED bulb according to any one of claims 1 to 11, wherein when the third emission color irradiates the object, the light measured at the position of the object satisfies the following (A).
(A) The distance D UVSSL from the black body radiation locus defined by ANSI C78.377 is −0.0325 ≦ D UVSSL ≦ −0.0075.
The LED light bulb according to claim 12, wherein when the third emission color irradiates an object, the light measured at the position of the object further satisfies the following (B) and (C).
(B) CIE 1976 L * a * b * a * in the color space of the following 15 types of modified Munsell color charts of # 01 to # 15 when the illumination by the light measured at the position of the object is mathematically assumed And b * values are a * n SSL and b * nSSL (where n is a natural number from 1 to 15),
CIE 1976 L * of the 15 types of corrected Munsell color charts when mathematically assuming illumination with reference light selected according to the correlated color temperature T SSL (K) of light measured at the position of the object . a * b * a * values in a color space, b * values of each a * nref, b * nref (where n is from 1 natural numbers 15) when the degree of saturation difference [Delta] C n is -2.7 ≦ [Delta] C n ≦ 18.6 (n is a natural number from 1 to 15)
The filling,
The average saturation difference represented by the following formula (1) satisfies the following formula (2),

When the maximum value of the saturation difference is ΔC max and the minimum value of the saturation difference is ΔC min , the difference ΔC max −ΔC min between the maximum value of the saturation difference and the minimum value of the saturation difference is
3.0 ≦ (ΔC max −ΔC min ) ≦ 19.6
Meet.
However, ΔC n = √ {(a * nSSL ) 2 + (b * nSSL ) 2 } −√ {(a * nref ) 2 + (b * nref ) 2 }.
15 types of modified Munsell color chart # 01 7.5 P 4/10
# 02 10 PB 4/10
# 03 5 PB 4/12
# 04 7.5 B 5/10
# 05 10 BG 6/8
# 06 2.5 BG 6/10
# 07 2.5 G 6/12
# 08 7.5 GY 7/10
# 09 2.5 GY 8/10
# 10 5 Y 8.5 / 12
# 11 10 YR 7/12
# 12 5 YR 7/12
# 13 10 R 6/12
# 14 5 R 4/14
# 15 7.5 RP 4/12
(C) The hue angle in the CIE 1976 L * a * b * color space of the above 15 types of modified Munsell color charts when the illumination by light measured at the position of the object is mathematically assumed is θ nSSL (degrees) (Where n is a natural number from 1 to 15)
CIE 1976 L * of the 15 types of corrected Munsell color charts when mathematically assuming illumination with reference light selected according to the correlated color temperature T SSL (K) of light measured at the position of the object . When the hue angle in the a * b * color space is θ nref (degrees) (where n is a natural number from 1 to 15), the absolute value of the hue angle difference | Δh n | is 0 ≦ | Δh n | ≦ 9. 0 (degrees) (n is a natural number from 1 to 15)
Meet.
However, Δh n = θ nSSL −θ nref .