WO2021182408A1

WO2021182408A1 - Light-emitting device and illumination device

Info

Publication number: WO2021182408A1
Application number: PCT/JP2021/009026
Authority: WO
Inventors: 圭亮堺
Original assignee: シチズン電子株式会社; シチズン時計株式会社
Priority date: 2020-03-09
Filing date: 2021-03-08
Publication date: 2021-09-16
Also published as: JP7321358B2; JPWO2021182408A1

Abstract

This light-emitting device comprises: a pair of electrodes; a first light-emitting element group that emits light when a current is supplied from the pair of electrodes; a second light-emitting element group that is connected in parallel to the first light-emitting element group, and that emits light when a current is supplied from the pair of electrodes; a reference voltage generation circuit that generates a reference voltage used to control one of a first current which flows to the first light-emitting element group and a second current which flows to the second light-emitting element group so that a current value of the first current and a current value of the second current reach a predetermined ratio; and a current control circuit that controls one of the first current and the second current on the basis of the reference voltage.

Description

Light emitting device and lighting device

This disclosure relates to a light emitting device and a lighting device.

A light emitting device that independently drives the light emission of a plurality of light emitting element trains by separately supplying a current from each of a plurality of pairs of electrodes to a plurality of light emitting element trains such as a light emitting diode (LED). It is known (see, for example, Japanese Patent Application Laid-Open No. 2016-119381 and Japanese Patent Application Laid-Open No. 2017-120897). The light emitting device described in JP-A-2016-119381 and JP-A-2017-120897 adjusts the chromaticity of the emitted light by adjusting the current value of the current supplied from a plurality of electrode pairs. be able to. However, in the light emitting devices described in JP-A-2016-119381 and JP-A-2017-120897, since the current is supplied to the light-emitting element array from a plurality of electrode pairs, the electrode region becomes large and the size of the light-emitting device becomes large. As the value increases, the shape of the wiring pattern becomes complicated, which may increase the design cost.

In International Publication No. 2016/03934, a pair of electrode pairs, two rows of LED rows to which current is supplied from the pair of electrode pairs, and one LED row of the two rows of LED rows are current only at low voltage. An LED light emitting device having a current control circuit that controls a current so as to flow a current is described. The LED light emitting device described in International Publication No. 2016/03934 is to supply a current from a pair of electrode pairs to two rows of LED rows at once, and to pass a current to one of the LED rows only at a low voltage. By controlling the current, it is possible to change the light emission color of the incandescent electrode during dimming.

However, in the light emitting device described in International Publication No. 2016/03934, when the applied voltage becomes high, current does not flow in one of the two rows of LED rows, and the LEDs included in both of the two rows of LED rows The light mixed with the emitted light is not emitted.

The present disclosure has been made to solve such a problem, and an object of the present invention is to provide a light emitting device capable of setting a current value of a current supplied from a pair of electrode pairs to a plurality of light emitting element trains to a predetermined ratio. do.

The light emitting device according to the present disclosure is connected in parallel to a pair of electrode pairs, a first light emitting element group that emits light when a current is supplied from the pair of electrode pairs, and a pair of light emitting element groups. When a current is supplied from the electrode pair, the current value of the second light emitting element group that emits light, the current value of the first current flowing through the first light emitting element group, and the current value of the second current flowing through the second light emitting element group are A reference voltage generation circuit that generates a reference voltage used to control one of the current values of the first current and the second current so as to have a predetermined ratio, and a first current and a first current based on the reference voltage. It has a current control circuit that controls one of the two currents and does not control the other of the first current and the second current.

Further, in the light emitting device according to the present disclosure, the reference voltage includes a second reference voltage used for controlling the current value of the second current, and the current control circuit has a second reference voltage based on the second reference voltage. It is preferable to include a second current control circuit that controls the second current so that the current value of the current becomes a predetermined ratio with respect to the current value of the first current.

Further, in the light emitting device according to the present disclosure, the first light emitting element group emits light of the first color, and the second light emitting element group emits light of a second color different from the first color. Is preferable.

Further, the light emitting device according to the present disclosure is connected in parallel to the first light emitting element group and the second light emitting element group, and when a current is supplied from the pair of electrode pairs, either the first color or the second color is supplied. The third light emitting element group that emits light of a third color different from the above and the current value of the third current flowing through the third light emitting element group are in a predetermined ratio with respect to the current value of the first current. It is preferable to further include a third current control circuit for controlling the three currents, and the reference voltage further includes a third reference voltage used for controlling the current value of the third current.

Further, in the light emitting device according to the present disclosure, the reference voltage generation circuit has a second resistance pair connected in series with the first light emitting element group, and the voltage divided voltage divided by the second resistance pair is used as the second reference. It is preferable to output the voltage to the second current control circuit.

Further, in the light emitting device according to the present disclosure, it is preferable that one of the resistors included in the second resistor pair is a variable resistor.

Further, in the light emitting device according to the present disclosure, the second current control circuit has a second switch having one end connected to the light emitting element at the final stage of the second light emitting element group and one end connected to the other end of the second switch. The second detection resistor, the input second reference voltage, and the second detection voltage applied to the second detection resistor are compared so that the second reference voltage matches the second detection voltage. It is preferable to have a second comparator that controls two switches.

Further, in the light emitting device according to the present disclosure, the reference voltage generation circuit further has a third resistance pair connected in parallel to the second resistance pair, and the voltage divided voltage divided by the third resistance pair is used as the third reference. It is preferable to output the voltage to the third current control circuit.

Further, in the light emitting device according to the present disclosure, it is preferable that one of the resistors included in the third resistor pair is a variable resistor.

Further, the light emitting device according to the present disclosure is connected in parallel to the first light emitting element group, the second light emitting element group, and the third light emitting element group, and when a current is supplied from the pair of electrode pairs, the first color, The current value of the fourth light emitting element group that emits light of a fourth color different from both the second color and the third color and the fourth current flowing through the fourth light emitting element group becomes the current value of the first current. It also has a fourth current control circuit that controls the third current so that it has a predetermined ratio to the current, and the reference voltage is the fourth reference voltage used to control the current value of the fourth current. Further included, the light of the first color is preferably white.

Further, in the light emitting device according to the present disclosure, the reference voltage generation circuit is a first current capable of controlling the first current so that the current value of the first current becomes a predetermined ratio with respect to the current value of the second current. The reference voltage generation circuit includes a control circuit and a second current control circuit capable of controlling the second current so that the current value of the second current becomes a predetermined ratio with respect to the current value of the first current. , It is preferable to generate a reference voltage so that one of the current values of the first current and the second current has a predetermined ratio with respect to the other current values of the first current and the second current.

Further, in the light emitting device according to the present disclosure, the forward voltage of one of the first light emitting element group and the second light emitting element group whose current value is controlled is the first light emitting element group and the second light emitting element group whose current value is not controlled. It is preferable that the reference voltage generation circuit generates a reference voltage so that the current values of the first current and the second current become desired values, which are lower than the other forward voltage of the above.

Further, the light emitting device according to the present disclosure includes a plurality of light emitting element groups and a plurality of light emitting elements, each of which is connected in parallel to a pair of electrode pairs and emits light when a current is supplied from the pair of electrode pairs. Each of the groups has a plurality of transistors to which either a collector or an emitter is connected, and a switching element for short-circuiting or releasing between the base and the collector of each of the plurality of transistors.

Further, in the light emitting device according to the present disclosure, any one of the plurality of transistors is short-circuited between the base and the collector via the switching element, and the other transistors of the plurality of transistors are short-circuited between the base and the collector via the switching element. It is preferable that the space between the two is opened.

Further, in the light emitting device according to the present disclosure, the forward voltage of the light emitting element group connected in series to the transistor in which the base and the collector are short-circuited via the switching element is the transistor in which the space between the base and the collector is opened. It is preferable that the voltage is higher than the forward voltage of the light emitting element group connected in series with.

Further, in the light emitting device according to the present disclosure, the reference voltage generation circuit has a second resistance pair connected in series with the first light emitting element group and a third resistance pair connected in parallel with the second resistance pair, and has a second resistance pair. Each resistor of the resistance pair and the third resistance pair has a first contact connected to the other of the second resistance pair, a second contact connected to the other of the third resistance pair, and a first contact and a second contact. It is preferable that the resistor is integrated with a resistor arranged between the resistor, a movable contact that can be connected to an arbitrary position of the resistor, and a third contact that is connected to the movable contact.

The lighting device according to the present disclosure is arranged at an operating member on which an internal gear is formed, a cylindrical shaft portion, a first gear that is arranged at one end of the shaft portion and screwed into the internal gear, and one end of the shaft portion. The ratio of the current flowing through the second light emitting element group according to the rotation of the third gear having the rotating member having the second gear and the third gear screwed into the second gear, and the second It has a current adjusting unit that adjusts the ratio of the current flowing through the three light emitting element groups, and the above light emitting device. When the third gear rotates in response to the rotation of the operating member in the first direction, the movable contact Moves so that the first voltage dividing resistance decreases and the third voltage dividing resistance increases, and when the third gear rotates in response to the operation member being rotated in the second direction opposite to the first direction. The movable contact moves so that the first voltage dividing resistance increases and the third voltage dividing resistance decreases.

In the light emitting device according to the present disclosure, the current value of the current supplied from a pair of electrode pairs to a plurality of light emitting element trains can be set to a predetermined ratio.

It is a perspective view of the lighting apparatus which mounts the light emitting device which concerns on 1st Embodiment. It is an exploded perspective view of the lighting apparatus shown in FIG. It is a circuit block diagram of the light emitting device which concerns on 1st Embodiment. It is a perspective view of the lighting apparatus which mounts the light emitting device which concerns on 2nd Embodiment. FIG. 5 is a perspective perspective view of a light emitting device, a diffusion member, and a current adjusting unit included in the lighting device shown in FIG. It is a circuit block diagram of the light emitting device which concerns on 2nd Embodiment. It is a figure which shows the 1st voltage dividing resistor and the 3rd voltage dividing resistor shown in FIG. It is a figure which shows the change of each current ratio of the 1st current, the 2nd current and the 3rd current when the resistance ratio of the 1st voltage dividing resistor and the 3rd voltage dividing resistor shown in FIG. 6 is changed. It is a chromaticity diagram which shows the optical characteristic of the light emitted from the light emitting device shown in FIG. It is a circuit block diagram of the light emitting device which concerns on 3rd Embodiment. It is a figure which shows the 1st voltage dividing resistor and the 3rd voltage dividing resistor shown in FIG. It is a chromaticity diagram which shows the optical characteristic of the light emitted from the light emitting device shown in FIG. It is a circuit block diagram of the light emitting device which concerns on 4th Embodiment. FIG. 5 is a chromaticity diagram showing a change in the chromaticity of the light emitted by the light emitting device shown in FIG. 7 when the first reference voltage, the second reference voltage, and the third reference voltage are changed. It is a circuit block diagram of the light emitting device which concerns on 5th Embodiment. It is a chromaticity diagram which shows the optical characteristic of the light emitted from the light emitting device shown in FIG. It is a circuit block diagram of the light emitting device which concerns on 6th Embodiment. (A) is a diagram showing an example of a light emitting state of a conventional light emitting device, and (b) is a diagram showing an example of a light emitting state of the light emitting device 6.

Hereinafter, the light emitting device according to the present disclosure will be described with reference to the drawings. However, it should be noted that the technical scope of the present disclosure is not limited to those embodiments and extends to the inventions described in the claims and their equivalents.

(Structure and function of a lighting device equipped with a light emitting device according to the first embodiment)
FIG. 1 is a perspective view of a lighting device equipped with a light emitting device according to the first embodiment, and FIG. 2 is an exploded perspective view of the lighting device shown in FIG.

The lighting device 110 according to the first embodiment includes a first housing 111, a second housing 112, a connector 113, a heat radiating sheet 114, a light emitting device 1, a first reflective member 115, and a diffusion member 116. , A downlight having a sealing member 117 and a second reflective member 118.

The first housing 111 is formed by drawing a metal having high thermal conductivity such as aluminum, and houses the second housing 112, the heat radiating sheet 114, the light emitting device 1, and the first reflecting member 115. The second housing 112 is formed of an insulating resin material such as polybutylene terephthalate. The second housing 112 is arranged along the inner wall of the first housing 111 to improve the insulating characteristics between the electronic component mounted on the light emitting device 1 and the first housing 111. In the second housing 112, a hole into which the heat radiating sheet 114 can be inserted is formed in a portion corresponding to the support portion where the first housing 111 supports the light emitting device 1. The connector 113 has a pair of power supply terminals that can be connected to an external power source, and supplies electric power to electronic components mounted on the light emitting device 1.

The heat radiating sheet 114 is a heat radiating material formed of a synthetic resin material having high thermal conductivity such as silicon resin. The heat radiating sheet 114 is arranged between the first housing 111 and the light emitting device 1, and releases heat generated while the light emitting device 1 emits light to the first housing 111. The light emitting device 1 is equipped with a light emitting element such as an LED and an electronic member, and emits light in response to supply of a power supply voltage via the connector 113. The light emitting device 1 is equipped with an electronic component that forms a power supply circuit that supplies electric power to a light emitting element mounted on the light emitting device 1.

The first reflective member 115 is an inverted conical member having an opening at the bottom, which is made of a synthetic resin material having high reflectance such as polycarbonate resin, and has outer edges on the first housing 111 and the second housing 112. It is supported and arranged so as to cover the light emitting device 1. The inner wall of the first reflecting member 115 is a reflecting surface that reflects the light emitted from the light emitting device 1. The diffusion member 116 is an arc-shaped member formed of a synthetic resin material such as polycarbonate, and its outer edge is supported by the first reflection member 115. The diffusion member 116 has a diffusion surface on which at least one of the front surface and the back surface is textured, and diffuses and emits the light incident from the light emitting device 1 through the first reflection member 115. The sealing member 117, also referred to as packing, is a ring-shaped member formed of a synthetic rubber material such as nitrile rubber, and is arranged between the diffusion member 116 and the second reflective member 118. The second reflective member 118 is a mortar-shaped member formed of a highly reflective member such as aluminum, and is supported by the diffusion member 116 via the sealing member 117 and the outer edge is supported by the first housing 111. NS. The inner wall 57 of the second reflecting member 118 is a reflecting surface that reflects the light emitted from the light emitting device 1.

(Configuration and function of light emitting device according to the first embodiment)
FIG. 3 is a circuit block diagram of the light emitting device according to the first embodiment. The components of the light emitting device according to the first embodiment shown in FIG. 3 are mounted on the single circuit board 1a shown in FIG.

The light emitting device 1 includes a power supply circuit 10, a first light emitting element group 11, a second light emitting element group 12, a third light emitting element group 13, a reference voltage generation circuit 20, a second current control circuit 30, and the like. It has a third current control circuit 35, a first electrode 101, and a second electrode 102.

The power supply circuit 10 includes a supply resistor 103, a supply Zener diode 104, a supply transistor 105, and a supply capacitor 106, and power supplies for

operational amplifiers

33 and 38 included in the second current control circuit 30 and the third current control circuit 35. Generate a voltage Vdd.

One end of the supply resistor 103 is connected to the first electrode 101, and the other end of the supply resistor 103 is connected to the cathode of the supply Zener diode 104 and the base of the supply transistor 105. The anode of the supply Zener diode 104 is connected to the second electrode 102. The collector of the supply transistor 105 is connected to the first electrode, and the emitter of the supply transistor 105 is connected to one end of the supply capacitor 106. The other end of the supply capacitor 106 is connected to the second electrode 102.

The power supply circuit 10 supplies the power supply voltage Vdd having a predetermined voltage value to the

operational amplifiers

33 and 38 of the second current control circuit 30 and the third current control circuit 35 by charging the supply capacitor 106.

The first light emitting element group 11 includes three first light emitting element rows 15 formed by six first light emitting elements 14 connected in series. Each of the plurality of first light emitting elements 14 is an LED die that emits light of a first color, for example, green. The number of the first light emitting elements 14 included in the first light emitting element row 15 may be 1 or 2 or more, and the number of the first light emitting element rows 15 may be 1, 2 or 4 or more. Further, the first light emitting element 14 contains an LED die that emits blue light and a light conversion material such as a phosphor such as YAG (Yttrium Aluminum Garnet) that converts the blue light emitted by the LED die into green. Moreover, it may be a light emitting element having a sealing material for sealing the LED die.

The second light emitting element group 12 includes three second light emitting element rows 17 formed by four second light emitting elements 16 connected in series. Each of the plurality of second light emitting elements 16 is an LED die that emits light of a second color, for example, blue, which is different from the first color of green. The number of the second light emitting elements 16 included in the second light emitting element row 17 may be 1 or 2 or more as long as it is smaller than the number of the first light emitting elements 14 connected in series in the first light emitting element row 15. The number of the second light emitting element rows 17 may be 1, 2, or 4 or more.

The third light emitting element group 13 includes three third light emitting element rows 19 formed by four third light emitting elements 18 connected in series. Each of the plurality of third light emitting elements 18 is an LED die that emits a third color different from both the first color green and the second color blue, for example, red light. The number of the third light emitting elements 18 included in the third light emitting element row 19 may be 1 or 2 or more as long as it is smaller than the number of the first light emitting elements 14 connected in series in the first light emitting element row 15. The number of the third light emitting element rows 19 may be 1, 2, or 4 or more. Further, the third light emitting element 18 contains an LED die that emits blue light and a light conversion material such as CASN such as a phosphor that converts the blue light emitted by the LED die into red, and the LED die. It may be a light emitting element having a sealing material for sealing.

The reference voltage generation circuit 20 is a voltage divider circuit having a first detection resistor 21, a second resistor pair 22, and a third resistor pair 23. The reference voltage generation circuit 20 uses the second reference voltage V used to control the current values of _{the second current I 2} flowing through the second light emitting element group 12 and _{the third current I 3} flowing through the third light emitting element group 13. generating a _second and a third reference voltage V _3. The second current I ₂ and the third current I ₃ are cases where the magnitudes of the resistor 21, the resistor 32, and the resistor 37 are equal to the current value of _{the first current I 1} whose current value flows through the first light emitting element group 11. Is controlled so as to have a predetermined ratio smaller than the first current I _1. The first detection resistor 21 is a resistance element having a resistance value of about several Ω, one end of which is connected to the first light emitting element group 11, and the other end of which is grounded. The first detection resistor 21 detects the voltage applied to both ends as the first reference voltage V ₁ .

The second resistance pair 22 has a first voltage dividing resistor 24 and a second voltage dividing resistor 25, and is connected in parallel to the first detection resistor 21. One end of the first voltage dividing resistor 24 is connected to the first light emitting element group 11 together with one end of the first detection resistor 21, and the other end of the first voltage dividing resistor 24 is connected to one end of the second voltage dividing resistor 25. The other end of the second voltage dividing resistor 25 is grounded together with the other end of the first detection resistor 21. The resistance value of each of the first voltage dividing resistor 24 and the second voltage dividing resistor 25 is about several kΩ, which is larger than the resistance value of the first detection resistor 21.

The third resistor pair 23 has a third voltage dividing resistor 26 and a fourth voltage dividing resistor 27, and is connected in parallel to the first detection resistor 21 and the second resistor pair 22. One end of the third voltage dividing resistor 26 is connected to the first light emitting element group 11 together with one end of the first detection resistor 21 and the first voltage dividing resistor 24, and the other end of the third voltage dividing resistor 26 is connected to the fourth voltage dividing resistor 27. Connected to one end of. The other end of the fourth voltage dividing resistor 27 is grounded together with the other ends of the first detection resistor 21 and the second voltage dividing resistor 25. The resistance value of each of the third voltage dividing resistor 26 and the fourth voltage dividing resistor 27 is about several kΩ, and the resistance value of the first detected resistor 21 is the same as that of the first voltage dividing resistor 24 and the second voltage dividing resistor 25. Greater than.

In the reference voltage generation circuit 20, the voltage at the connection portion between the first voltage dividing resistor 24 and the second voltage dividing resistor 25 is set as the second reference voltage V _{2 which is the voltage divided voltage divided by the second resistance pair 22.} Output to the second current control circuit 30. Further, the reference voltage generation circuit 20 is a third reference voltage V, which is a voltage dividing voltage obtained by dividing the voltage at the connection portion between the third voltage dividing resistor 26 and the fourth voltage dividing resistor 27 by the third resistance pair 23. _It is output to the third current control circuit 35 as 3.

The second current control circuit 30 includes a second switch 31, a second detection resistor 32, and a second comparator 33. The second switch 31 is an nMOSFET, the drain at one end is connected to the second light emitting element group 12, the source at the other end is connected to one end of the second detection resistor 32, and the gate as the control terminal is the second. It is connected to the output terminal of the comparator 33. The other end of the second detection resistor 32 is grounded. The first input terminal of the second comparator 33 is connected to the other end of the first voltage dividing resistor 24 and one end of the second voltage dividing resistor 25, and the second reference voltage V ₂ is input. The second input terminal of the second comparator 33 is connected to one end of the second detection resistor 32, and the second detection voltage V _D2, which is the voltage across the second detection resistor 32, is input. The second comparator 33 compares the input second reference voltage V ₂ _{with the second detection voltage V D} 2 applied to the second detection resistor 32, and the second reference voltage V ₂ is the second detection voltage V. The second switch 31 is controlled so as to match _D2.

The third current control circuit 35 includes a third switch 36, a third detection resistor 37, and a third comparator 38. The third switch 36 is an nMOSFET, the drain at one end is connected to the third light emitting element group 13, the source at the other end is connected to one end of the third detection resistor 37, and the gate as the control terminal is the third. It is connected to the output terminal of the comparator 38. The other end of the third detection resistor 37 is grounded. The first input terminal of the third comparator 38 is connected to the other end of the third voltage dividing resistor 26 and one end of the fourth voltage dividing resistor 27, and the third reference voltage V ₃ is input. The second input terminal of the third comparator 38 is connected to one end of the third detection resistor 37, and the third detection voltage V _D3, which is the voltage across the third detection resistor 37, is input. The third comparator 38 compares the input third reference voltage V ₃ _{with the third detection voltage V D} 3 applied to the third detection resistor 37, and the third reference voltage V ₃ is the third detection voltage V. The third switch 36 is controlled so as to match _D3.

Each of the first electrode 101 and the second electrode 102 is connected to the current source 100, and the current supplied from the current source 100 is applied to the first light emitting element group 11, the second light emitting element group 12, and the third light emitting element group 13. Supply to each. The current source 100 is a variable constant current power supply capable of changing the current supplied to the first electrode 101.

_{In the light emitting device 1, the current values of the second current I 2} flowing through the second light emitting element group 12 and _{the third current I 3} flowing through the third light emitting element group 13 of _{the first current I 1} flowing through the first light emitting element group 11 _{The second current I 2} and the third current I ₃ are controlled so as to have a predetermined ratio with respect to the current value. The second current control circuit 30 and the third current control circuit 35 have a second current I so that _{the second reference voltage V 2} and the third reference voltage V ₃ have a predetermined ratio to the first reference voltage V _1. _{The second} and third currents I ₃ are feedback-controlled. When the second reference voltage V ₂ and the third reference voltage V ₃ become a predetermined ratio with respect to the first reference voltage V ₁ , the second current I flowing through the second light emitting element group 12 and the third light emitting element group 13 _{The 2} and the 3rd current I ₃ have a predetermined ratio with respect to _{the 1st current I 1} flowing through the 1st light emitting element group 11.

For example, when the _{ratios of the second reference voltage V 2} and the third reference voltage V ₃ to the first reference voltage V ₁ are 3/5 and 2/5, the second current control circuit 30 and the third current control circuit 35 _{, The second current I 2} and the third current I ₃ are controlled so that the ratio to the first current I _{1 is 3/5 and 2/5.}

(Action and effect of the light emitting device according to the first embodiment)
The light emitting device 1 _{controls the second current I 2} and the third current I _{3 so as} to have a predetermined ratio with respect to the first current I ₁ , so that the first light emitting element group 11 to the third light emitting element group 13 Light obtained by mixing the light emitted from the light source in a desired ratio can be emitted regardless of the supplied current. Since the light emitting device 1 fixes the ratio of the current, not the absolute value of the current, even if the current input from the current source 100 changes due to dimming or the like, the first light emitting element group 11 to the third light emitting element group 13 The ratio of the light emitted from each of the above is kept constant.

Further, since the electronic components of the light emitting device 1 including the power supply circuit 10 are mounted on a single circuit board 1a, the circuit board 1a can be replaced with a circuit board on which another light emitting device is mounted to illuminate the light emitting device 1. The device 110 can mount various light emitting devices in the same housing.

(Structure and function of a lighting device equipped with a light emitting device according to the second embodiment)
FIG. 4 is a perspective view of the lighting device equipped with the light emitting device according to the second embodiment, and FIG. 5 is a perspective perspective view of the light emitting device, the diffusion member, and the current adjusting unit included in the lighting device shown in FIG.

The lighting device 120 according to the second embodiment illuminates that the light emitting device 2 and the diffusion member 126, which is an example of an operating member in which the internal gear 126a is formed in the vicinity of the upper end, are provided in place of the light emitting device 1 and the diffusion member 116. Different from device 110. Further, the illuminating device 120 is different from the illuminating device 110 in that it has a rotating member 121 and a current adjusting unit 127. Since the components and functions of the lighting device 120 other than the rotating member 121, the light emitting device 2, the diffusion member 126, and the current adjusting unit 127 are the same as the components and functions of the lighting device 110 with the same reference numerals, A detailed description will be omitted here.

The rotating member 121 has a shaft portion 122, a first gear 123, and a second gear 124. The shaft portion 122 is a columnar member extending in the normal direction of the circuit board 2a of the light emitting device 2, and is arranged so as to penetrate the through hole formed in the first reflection member 115. In the shaft portion 122, the first gear 123 is arranged at the upper end and the second gear 124 is arranged at the lower end. The first gear 123 is screwed into the internal gear 126a formed on the inner wall of the upper end of the diffusion member 126. The second gear 124 is an internal gear formed inside the lower end of the shaft portion 122, and is screwed into the current adjusting portion 127.

The current adjusting unit 127 has a third gear 128 screwed into the second gear 124, and the ratio of the current flowing through the second light emitting element group 12 and the third light emitting as the third gear 128 rotates. This is a current adjusting device that adjusts the ratio of the current flowing through the element group 13.

When the diffusion member 126 is rotated by the operator in the direction indicated by the arrow A, the third gear 128 is rotated via the rotating member 121, the ratio of the current flowing through the second light emitting element group 12 is increased, and the second is 3 The ratio of the current flowing through the light emitting element group 13 decreases. On the other hand, when the diffusion member 126 is rotated by the operator in the direction opposite to the direction indicated by the arrow A, the ratio of the current flowing through the second light emitting element group 12 decreases and the current flowing through the third light emitting element group 13 decreases. The ratio increases.

(Configuration and function of light emitting device according to the second embodiment)
FIG. 6 is a circuit block diagram of the light emitting device 2 according to the second embodiment.

The light emitting device 2 is different from the light emitting device 1 in that it has a reference voltage generation circuit 40 instead of the reference voltage generation circuit 20. Since the components and functions of the light emitting device 2 other than the reference voltage generation circuit 40 are the same as the components and functions of the light emitting device 1 having the same reference numerals, detailed description thereof will be omitted here.

The reference voltage generation circuit 40 differs from the reference voltage generation circuit 20 in that it has a second resistance pair 42 and a third resistance pair 43 instead of the second resistance pair 22 and the third resistance pair 23. The second resistor pair 42 has a first voltage divider resistor 44 in place of the first voltage divider resistor 24, and the third resistor pair 43 has a third voltage divider resistor 46 in place of the third voltage divider resistor 26. Since the components and functions of the reference voltage generation circuit 40 other than the first voltage dividing resistor 44 and the third voltage dividing resistor 46 are the same as the components and functions of the reference voltage generating circuit 20 having the same reference numerals. , A detailed description is omitted here.

FIG. 7 is a diagram showing a first voltage dividing resistor 44 and a third voltage dividing resistor 46.

The first voltage dividing resistor 44 and the third voltage dividing resistor 46 are integrated by the resistor 400, the first terminal 401, the second terminal 402, the third terminal 403, and the movable contact 404. The resistor 400 is a high-resistance conductor such as a nickel-chromium alloy, and a first terminal 401 connected to the second voltage dividing resistor 25 is arranged at one end and connected to the fourth voltage dividing resistor 27. The two terminals 402 are arranged at the other end. The movable contact 404 is a conductor in which a third terminal 403 connected to the first light emitting element group 11 is arranged at one end and can be connected to an arbitrary position of the resistor 400. The resistance values of the first voltage dividing resistor 44 and the third voltage dividing resistor 46 are continuously changed according to the place where the movable contact 404 comes into contact with the resistor 400.

The movable contact 404 moves in response to the rotation of the third gear 128 of the current adjusting unit 127. When the third gear 128 rotates in response to the rotation of the diffusion member 126 in the first direction indicated by the arrow A, the movable contact 404 has a decrease in the first partial pressure resistance 44 and an increase in the third partial pressure resistance 46. Move to do. By moving so that the first voltage dividing resistor 44 decreases and the third voltage dividing resistor 46 increases, the ratio of the current flowing through the second light emitting element group 12 increases, and the current flows through the third light emitting element group 13. The ratio of current decreases.

Further, when the third gear 128 rotates in response to the rotation of the diffusion member 126 in the second direction opposite to the first direction indicated by the arrow A, the movable contact 404 has an increased first partial pressure resistance 44. The third partial pressure resistance 46 moves so as to decrease. By moving so that the first voltage dividing resistor 44 increases and the third voltage dividing resistor 46 decreases, the ratio of the current flowing through the second light emitting element group 12 decreases, and the current flows through the third light emitting element group 13. The ratio of current increases.

(Action and effect of the light emitting device according to the second form)
In the light emitting device 2, since the reference voltage generation circuit 40 has the first voltage dividing resistor 44 and the third voltage dividing resistor 46 which are variable resistors, the first reference voltage of the second reference voltage V ₂ and the third reference voltage V ₃ is provided. The _{ratio to V 1} can be changed continuously. The light emitting device 2 _{changes the ratio of the second reference voltage V 2} and the third reference voltage V ₃ to the first reference voltage V ₁ to cause a second current flowing through the second light emitting element group 12 and the third light emitting element group 13. The _{ratio of the I 2} and the third current I ₃ _{to the first current I 1} flowing through the first light emitting element group 11 can be continuously changed.

_{FIG. 8 shows changes in the current ratios of the first current I 1} , the second current I _2, and the third current I ₃ when the resistance ratios of the first voltage dividing resistor 44 and the third voltage dividing resistor 46 are changed. It is a figure which shows. In FIG. 8, the horizontal axis shows the resistance stages of the first voltage dividing resistor 44 and the third voltage dividing resistor 46, and the vertical axis represents the first current I ₁ , the second current I _2, and the third current I ₃ , respectively. Indicates the current ratio [%]. _{In FIG. 8, the diamond mark indicates the first current I 1} flowing through the first light emitting element group 11 _{, the triangle mark indicates the second current I 2} flowing through the second light emitting element group 12, and the square mark indicates the third light emitting element group. The third current I ₃ flowing through 13 is shown.

When the resistance step is "0", the first current I ₁ and the third current I ₃ are 45%, and the second current I ₂ is 10%. As the resistance stage increases, the second current I ₂ increases, the third current I ₃ decreases, and when the resistance stage is "10", the first current I ₁ and the second current I ₂ are 45 [%]. And the third current I ₃ becomes 10%. The maximum and minimum values of the second current and the third current and their intermediate values can be adjusted by changing the values of the resistor 25 or the resistor 27, for example.

_{In the light emitting device 2, the current value of the first current I 1} corresponding to the first light emitting element group 11 that emits green light is the second light emitting element group 12 and the third light emitting element group that emit blue and red light. It is larger than the respective current values of the second current I ₂ and the third current I _{3 corresponding to 13.} Further, in the light emitting device 2, _{the current value of the third current I 3} decreases as the current value of the second current I ₂ increases. The light emitting device 2 is emitted from the second light emitting element 16 and the third light emitting element 18 by adjusting the wavelength of the light emitted from the first light emitting element 14, the second light emitting element 16, and the third light emitting element 18. By changing the ratio of light, it is possible to emit light along the blackbody locus.

FIG. 9 is a chromaticity diagram showing the optical characteristics of the light emitted from the light emitting device 2. In FIG. 9, the fine curve L20 shows a blackbody locus. Point P21 indicates the chromaticity of the light emitted from the first light emitting element group 11, point P22 indicates the chromaticity of the light emitted from the second light emitting element group 12, and point P23 indicates the chromaticity of the light emitted from the thirteenth light emitting element group 13. Indicates the chromaticity of the emitted light. The thick curve L24 indicates an effective color gamut indicating the chromaticity of light that can be emitted by the light emitting device 2.

The light emitting device 2 can emit light having a chromaticity that matches the blackbody locus over a predetermined color gamut. The light emitting device 2 is adjusted so that the light emitted from the first light emitting element group 11 to the third light emitting element group 13 emits light having a color deviation (Duv) of ± 0.01 or less with respect to the blackbody locus. can do.

(Configuration and function of light emitting device according to the third embodiment)
FIG. 10 is a circuit block diagram of the light emitting device according to the third embodiment.

The light emitting device 3 is different from the light emitting device 2 in that it has a reference voltage generation circuit 50 instead of the reference voltage generation circuit 40. Further, the light emitting device 3 is different from the light emitting device 2 in that it further has a current ratio control circuit 60. The components and functions of the light emitting device 3 other than the reference voltage generation circuit 50 and the current ratio control circuit 60 are the same as the components and functions of the light emitting device 2 having the same reference numerals. Is omitted.

The reference voltage generation circuit 50 differs from the reference voltage generation circuit 40 in that it has a second resistance pair 52 and a third resistance pair 53 in place of the second resistance pair 42 and the third resistance pair 43. The second resistance pair 52 has a first voltage dividing resistor 54 in place of the first voltage dividing resistor 44, and the third resistance pair 53 has a third voltage dividing resistor 56 in place of the third voltage dividing resistor 46. Since the components and functions of the reference voltage generation circuit 50 other than the first voltage dividing resistor 54 and the third voltage dividing resistor 56 are the same as the components and functions of the reference voltage generating circuit 40 having the same reference numerals. , A detailed description is omitted here.

FIG. 11 is a diagram showing a first voltage dividing resistor 54 and a third voltage dividing resistor 56.

The first voltage dividing resistor 54 and the third voltage dividing resistor 56 are integrated by a resistor 500, a first terminal 501, a second terminal 502, a third terminal 503, a plurality of switches 504, and an input terminal 505. The resistor 500 is a high-resistance conductor such as a nickel-chromium alloy, and a first terminal 501 connected to the second voltage dividing resistor 25 is arranged at one end and connected to the fourth voltage dividing resistor 27. The two terminals 502 are arranged at the other end. Each of the plurality of switches 504 is, for example, an nMOSFET, and the drain is connected to the third terminal 503 connected to the first light emitting element group 11, the source is connected to the resistor 500, and the current ratio control circuit 60 is connected. A gate is connected to the input terminal 505. The resistance values of the first voltage dividing resistor 54 and the third voltage dividing resistor 56 are continuously changed according to the position of the switch 504 to be turned on.

The current ratio control circuit 60 includes a communication unit 61, a storage unit 62, a control unit 63, and an output unit 64.

The communication unit 61 is a communication interface such as I2C, and is electrically connected to a higher-level control device (not shown) that controls communication of the light emitting device 3. The communication unit 61 has a pad for connecting to an external device such as a host control device. The pad included in the communication unit 61 is arranged on the surface of the substrate forming the light emitting device 3, for example. By arranging the pad included in the communication unit 61 on the surface of the substrate, the light emitting device 3 can reduce the number of wirings.

The storage unit 62 includes, for example, a semiconductor memory device such as a ROM (Read Only Memory) or a RAM (Random Access Memory). The storage unit 62 stores an operating system program, a driver program, a control program, data, and the like used for processing by the control unit 63.

The control unit 63 has one or a plurality of processors and peripheral circuits thereof, and controls the resistance ratio between the first voltage dividing resistor 54 and the third voltage dividing resistor 56, for example, a CPU (Central). ProcessingUnit). Further, the control unit 63 may be formed of a discrete product such as a transistor. The control unit 63 controls the resistance ratio between the first voltage dividing resistor 54 and the third voltage dividing resistor 56 based on the chromaticity control signal input from the upper control device via the communication unit 61.

The output unit 64 is electrically connected to the first voltage dividing resistor 54 and the third voltage dividing resistor 56 via a communication line, and outputs a control signal indicating a switch 504 to be turned on to the input terminal 505. The control signal output from the output unit 64 indicates that any one of the plurality of switches 504 is turned on and the other switch 504 is turned off.

(Action and effect of the light emitting device according to the third form)
The light emitting device 3 controls the resistance ratio between the first voltage dividing resistor 54 and the third voltage dividing resistor 56 based on the chromaticity control signal input from the upper control device, so that the second light emitting element group 12 _{And the ratio of the second current I 2} and the third current I ₃ flowing through the third light emitting element group 13 can be changed.

FIG. 12 is a chromaticity diagram showing the optical characteristics of the light emitted from the light emitting device 3. In FIG. 12, the curve L30 shows a blackbody locus. Point P31 indicates the chromaticity of the light emitted from the first light emitting element group 11, point P32 indicates the chromaticity of the light emitted from the second light emitting element group 12, and point P33 indicates the chromaticity of the light emitted from the thirteenth light emitting element group 13. Indicates the chromaticity of the emitted light. The region R34 indicates an effective color gamut indicating the chromaticity of light that can be emitted by the light emitting device 3.

Although the effective color gamut of the light emitting device 3 is narrower than the light source color gamut formed by connecting the points P31, P32, and P33, it emits light having the chromaticity desired for the lighting device including the blackbody locus. can do.

(Configuration and function of light emitting device according to the fourth embodiment)
FIG. 13 is a circuit block diagram of the light emitting device according to the fourth embodiment.

The light emitting device 4 is different from the light emitting device 1 in that it does not have the reference voltage generation circuit 20. Further, the light emitting device 4 is different from the light emitting device 1 in that it has a current sensor 55, a first current control circuit 70, and a reference voltage generation circuit 75. Since the components and functions of the light emitting device 4 other than the current sensor 55, the first current control circuit 70, and the reference voltage generation circuit 75 are the same as the components and functions of the light emitting device 1 with the same reference numerals, A detailed description will be omitted here.

The current sensor 55 is, for example, a current sensor such as a current detection amplifier, and is arranged between the first electrode 101 and the first light emitting element group 11, the second light emitting element group 12, and the third light emitting element group 13. The current sensor 55 detects and detects a detection current _ID _{including a first current I 1} , a second current I ₂ and a third current I ₃ flowing through the first light emitting element group 11 to the third light emitting element group 13. The current _ID is output to the reference voltage generation circuit 75 as the corresponding voltage information.

The first current control circuit 70 includes a first switch 71, a first reference resistor 72, and a first comparator 73. The first switch 71 is an nMOSFET, the drain at one end is connected to the first light emitting element group 11, the source at the other end is connected to one end of the first reference resistor 72, and the gate as the control terminal is the first. It is connected to the output terminal of the comparator 73. The other end of the first reference resistor 72 is grounded together with the other ends of the second detection resistor 32 and the third detection resistor 37. The first input terminal of the first comparator 73 and the first input terminal of the second comparator 33 and the third comparator 38 are connected to the reference voltage generation circuit 75, respectively. The second input terminal of the first comparator 73 is connected to one end of the first reference resistor 72, and the first detection voltage V _D1 which is the voltage across the first reference resistor 72 is input.

The reference voltage generation circuit 75 includes an input unit 76, a storage unit 77, a control unit 78, and an output unit 79. The first current I _1, as in the current value of the second current I ₂ and the third current I ₃ is the predetermined ratio, the first current I _1, either the second current I ₂ and the third current I ₃ 1 Generates a reference voltage used to control one or two current values.

The input unit 76 is electrically connected to the current sensor 55, and a detection current signal indicating the detection current ID detected by the current sensor 55 is input.

The storage unit 77 includes, for example, a semiconductor memory device such as a ROM or RAM. The storage unit 77 stores an operating system program, a driver program, a control program, data, and the like used for processing by the control unit 78.

The control unit 78 has one or more processors and peripheral circuits thereof, and is, for example, a CPU. Further, the control unit 78 may be formed by a transistor. The control unit 78 uses the first reference voltage V used to control _{the first current I 1} , the second current I ₂ and the third current I ₃ flowing through the first light emitting element group 11 to the third light emitting element group 13. _1. Generates a second reference voltage V ₂ and a third reference voltage V _3.

The control unit 78 has a first reference voltage so that _{the first current I 1} , the second current I ₂ and the third current I ₃ flowing through the first light emitting element group 11 to the third light emitting element group 13 have a predetermined ratio. Generates V ₁ , a second reference voltage V _2, and a third reference voltage V _3. Control unit 78, first current I _1, as the other two current values for any one current value of the second current I ₂ and the third current I ₃ becomes a predetermined ratio, the first current I ₁ , A reference voltage for controlling any two current values of the second current I ₂ and the third current I _{3 is generated.} The control unit 78 emits light of the same voltage as the power supply voltage Vdd to the first input terminal of the comparator corresponding to the light emitting element group in which the current controlled by the reference voltage does not flow, that is, the light emitting element group functioning as the master. Outputs a voltage that does not control the current flowing through the element group. Further, a current having a predetermined ratio to _{the detected current ID} is passed through the first input terminal of the comparator corresponding to the light emitting element group in which the current controlled by the reference voltage flows, that is, the light emitting element group functioning as a slave. The reference voltage is output.

For example, when the _{current values of the second current I 2} and the third current I ₃ are controlled and the current value of the first current I ₁ is not controlled, the voltage is the same as the power supply voltage Vdd at the first input terminal of the first comparator 73. Is entered. _{A second reference in which the current values of the second current I 2} and the third current I ₃ are a predetermined ratio to the current value of the first current I ₁ at the first input terminals of the second comparator 33 and the third comparator 38. the voltage _V2 and the third reference voltage V ₃ is input.

Further, when the _{current values of the first current I 1} and the third current I ₃ are controlled and the current values of the second current I ₂ are not controlled, the same voltage as the power supply voltage Vdd is applied to the first input terminal of the second comparator 33. Is entered. _{A first reference in which the current values of the first current I 1} and the third current I ₃ are a predetermined ratio to the current values of the second current I ₂ at the first input terminals of the first comparator 73 and the third comparator 38. The voltage V ₁ and the third reference voltage V ₃ are input.

Further, when the _{current values of the first current I 1} and the second current I ₂ are controlled and the current value of the third current I ₃ is not controlled, the same voltage as the power supply voltage Vdd is applied to the first input terminal of the third comparator 38. Is entered. _{A first reference in which the current values of the first current I 1} and the second current I ₂ are a predetermined ratio to the current values of the third current I ₃ at the first input terminals of the first comparator 73 and the second comparator 33. The voltage V ₁ and the second reference voltage V ₂ are input.

The output unit 79 is electrically connected to the first input terminal of the first comparator 73, the first input terminal of the second comparator 33, and the first input terminal of the third comparator 38, and the first unit generated by the control unit 78 is generated. The reference voltage V ₁ , the second reference voltage V ₂ and the third reference voltage V ₃ are output.

(Action and effect of the light emitting device according to the fourth form)
The light emitting device 4 controls the first current control circuit 70, the second current control circuit 30, and the third current control circuit 35 by _{the first reference voltage V 1} , the second reference voltage V _2, and the third reference voltage V _3. Therefore, the first current I ₁ , the second current I ₂ and the third current I ₃ can be controlled to have a predetermined ratio.

FIG. 14 is a chromaticity diagram showing a change in the chromaticity of the light emitted by the light emitting device 4 when the first reference voltage V ₁ , the second reference voltage V ₂ and the third reference voltage V _{3 are changed.} In FIG. 14, the solid line indicates the range of light that can be emitted by the light emitting device 4, and the broken line indicates the blackbody locus.

The light emitting device 4 has a _{first current I 1} , a second current flowing through the first light emitting element group 11 to the third light emitting element group 13 by _{the first reference voltage V 1} , the second reference voltage V _2, and the third reference voltage V _3. The current I ₂ and the third current I ₃ can be controlled so that the chromaticity of the light emitted by the light emitting device 4 follows the blackbody locus.

(Configuration and function of light emitting device according to the fifth embodiment)
FIG. 15 is a circuit block diagram of the light emitting device according to the fifth embodiment.

The light emitting device 5 is different from the light emitting device 2 in that it has a reference voltage generation circuit 84 instead of the reference voltage generation circuit 40. Further, the light emitting device 5 is different from the light emitting device 2 in that it further has a current ratio control circuit 60. The components and functions of the light emitting device 5 other than the reference voltage generation circuit 84 and the current ratio control circuit 60 are the same as the components and functions of the light emitting device 2 having the same reference numerals. Is omitted.

The light emitting device 5 includes a power supply circuit 10, a first light emitting element group 80, a second light emitting element group 81, a third light emitting element group 82, a fourth light emitting element group 83, a reference voltage generation circuit 84, and the like. It has a second current control circuit 30, a third current control circuit 35, and a fourth current control circuit 89. The light emitting device 5 further includes a current ratio control circuit 60, a first electrode 101, and a second electrode 102.

The power supply circuit 10, the second current control circuit 30, the third current control circuit 35, the current ratio control circuit 60, the first electrode 101 and the second electrode 102 have already been described with reference to FIGS. 3 and 10. Then, detailed explanation is omitted.

The first light emitting element group 80 is formed by six first light emitting elements 80a connected in series. The first light emitting element 80a contains an LED die that emits blue light and a light conversion material such as a phosphor such as YAG that converts the blue light emitted by the LED die into yellow, and seals the LED die. It is a light emitting element that has a sealing material to stop and emits white light.

The second light emitting element group 81 is formed by four second light emitting elements 81a connected in series. The second light emitting element 81a is a light emitting diode that emits light of the first color that is blue.

The third light emitting element group 82 is formed by four third light emitting elements 82a connected in series. The third light emitting element 82a contains an LED die that emits blue light and a light conversion material such as a phosphor such as YAG that converts the blue light emitted by the LED die into green, and seals the LED die. It is a light emitting element that has a sealing material to stop and emits green light.

The fourth light emitting element group 83 is formed by four fourth light emitting elements 83a connected in series. The fourth light emitting element 83a contains an LED die that emits blue light and a light conversion material such as a phosphor such as CASN that converts the blue light emitted by the LED die into red, and seals the LED die. It is a light emitting element that has a sealing material to stop and emits red light.

The reference voltage generation circuit 84 is a voltage divider circuit having a first detection resistor 85, a second resistor pair 86, a third resistor pair 87, and a fourth resistor pair 88. Like the first detection resistor 21, the first detection resistor 85 is a resistance element having a resistance value of about several Ω, one end of which is connected to the first light emitting element group 80, and the other end of which is grounded. The second resistance pair 86 has a first voltage dividing resistor 86a and a second voltage dividing resistor 86b, and generates a second reference voltage V ₂ _{that controls a second current I 2 flowing through the second light emitting element group 81.} The third resistance pair 87 has a third voltage dividing resistor 87a and a fourth voltage dividing resistor 87b, and generates a third reference voltage V ₃ _{that controls a third current I 3 flowing through the third light emitting element group 82.} The fourth resistor pair 88 has a fifth voltage dividing resistor 88a and a sixth voltage dividing resistor 88b, and generates a fourth reference voltage V ₄ _{that controls a fourth current I 4 flowing through the fourth light emitting element group 83.}

The first voltage dividing resistor 86a and the fifth voltage dividing resistor 88a are variable resistors. Since the first voltage dividing resistor 86a and the fifth voltage dividing resistor 88a have the same structure as the first voltage dividing resistor 54 and the third voltage dividing resistor 56 described with reference to FIG. 11, they are described in detail here. The description is omitted.

The fourth current control circuit 89 has a fourth switch 89a, a fourth detection resistor 89b, and a fourth comparator 89c, and has the same configuration as the second current control circuit 30 and the third current control circuit 35.

FIG. 16 is a chromaticity diagram showing the optical characteristics of the light emitted from the light emitting device 5. In FIG. 16, the fine curve L50 shows a blackbody locus. Point P51 indicates the chromaticity of the light emitted from the first light emitting element group 80, point P52 indicates the chromaticity of the light emitted from the second light emitting element group 81, and point P53 indicates the chromaticity of the light emitted from the 82nd light emitting element group 13. The chromaticity of the emitted light is indicated, and the point P54 indicates the chromaticity of the light emitted from the fourth light emitting element group 83. The region R55 indicates an effective color gamut indicating the chromaticity of light that can be emitted by the light emitting device 5.

In the light emitting device 5, the first light emitting element group 80 having high luminous efficiency emits white light, and the second light emitting element group 81 to the fourth light emitting element group 83 having lower luminous efficiency than the first light emitting element group 80 are blue. , Green and red light are emitted respectively. The light emitting device 5 emits white light from the first light emitting element group 80 having high luminous efficiency, and emits blue, green, and red light as complementary colors from the second light emitting element group 81 to the fourth light emitting element group 83, respectively. As a result, the minimum color range can be realized with a simple circuit configuration while maintaining high luminous efficiency.

Further, the light emitting device 5 has a desired color and color temperature when the color of the light emitted from each of the first light emitting element group 80 to the fourth light emitting element group 83 fluctuates due to manufacturing variation or the like. The current ratio control circuit 60 may be preset so that light is emitted. The light emitting device 5 can reduce the chromaticity tolerance by presetting the current ratio control circuit 60 so that light having a desired color and color temperature is emitted.

(Configuration and function of light emitting device according to the sixth embodiment)
FIG. 17 is a circuit block diagram of the light emitting device according to the sixth embodiment.

The light emitting device 6 is switched between the first light emitting element group 91, the second light emitting element group 92, the third light emitting element group 93, the first transistor 94, the second transistor 95, the third transistor 96, and the first switching. It has an element 97, a second switching element 98, and a third switching element 99. The light emitting device 6 further includes a first electrode 101 and a second electrode 102.

Each of the first light emitting element group 91 to the third light emitting element group 93 includes a plurality of LEDs connected in series. The LEDs included in the first light emitting element group 91 to the third light emitting element group 93 emit light of the same color such as blue. The LEDs included in the first light emitting element group 91 to the third light emitting element group 93 are, for example, a green phosphor that converts the blue light emitted by the LED into green and emits the blue light, and the blue light emitted by the LED into red. It is sealed with a sealing material containing a red phosphor that is converted and emitted.

Each of the first transistor 94, the second transistor 95, and the third transistor 96 is an NPN bipolar transistor. The collector of the first transistor 94 is connected to the first light emitting element group 91, the collector of the second transistor 95 is connected to the second light emitting element group 92, and the collector of the third transistor 96 is connected to the third light emitting element group 93. NS. The emitters of the first transistor 94, the second transistor 95, and the third transistor 96 are grounded.

One end of the first switching element 97 is connected to the base of the first transistor 94, and the other end of the first switching element 97 is connected to the collector of the first transistor 94. The space between one end and the other end of the first switching element 97 is open, and when the space between one end and the other end of the first switching element 97 is short-circuited by, for example, a solder jumper or wire bonding, the first switching element 97 Shorts between the base and collector of the first transistor 94.

One end of the second switching element 98 is connected to the base of the second transistor 95, and the other end of the second switching element 98 is connected to the collector of the second transistor 95. The space between one end and the other end of the second switching element 98 is open, and when the space between one end and the other end of the second switching element 98 is short-circuited by, for example, a solder jumper or wire bonding, the second switching element 98 Shorts between the base and collector of the second transistor 95.

One end of the third switching element 99 is connected to the base of the third transistor 96, and the other end of the third switching element 99 is connected to the collector of the third transistor 96. The space between one end and the other end of the third switching element 99 is open, and when the space between one end and the other end of the third switching element 99 is short-circuited by, for example, a solder jumper or wire bonding, the third switching element 99 Shorts between the base and collector of the third transistor 96.

When any one of the first switching element 97, the second switching element 98, and the third switching element 99 is short-circuited, the first transistor 94, the second transistor 95, and the third transistor 96 form a current mirror circuit. The first transistor 94, the second transistor 95, and the third transistor 96 form a current mirror circuit, so that the first current I ₁ and the second current I flow through the first light emitting element group 91 to the third light emitting element group 93. The current values of the _second and third currents I _{3 are the same.}

The switching element to be short-circuited is determined according to the forward voltage of each of the first light emitting element group 91 to the third light emitting element group 93. For example, the switching element connected to the light emitting element group having the highest threshold voltage for starting light emission in the first light emitting element group 91 to the third light emitting element group 93 may be short-circuited. By short-circuiting the switching element connected to the light emitting element group having the highest threshold voltage, the current flowing in the light emitting element group having the smallest current during light emission is adjusted to the current flowing in the first light emitting element group 91 to No. It can flow through all of the three light emitting element groups 93. For example, when the threshold voltage at which the first light emitting element group 91 starts emitting light is higher than the threshold voltage at which the second light emitting element group 92 and the third light emitting element group 93 start emitting light, the first light emitting element group The first switching element 97 connected to 91 is short-circuited.

(Action and effect of the light emitting device according to the sixth embodiment)
By matching the current flowing through the first light emitting element group 91 to the third light emitting element group 93 at the time of light emission with the current flowing through the light emitting element group having the highest threshold voltage, the first light emitting element group 91 to the third light emitting element group The light emitted from 93 can be made uniform.

FIG. 18A is a diagram showing an example of a light emitting state of a conventional light emitting device, and FIG. 18B is a diagram showing an example of a light emitting state of the light emitting device 6. The figures shown in FIGS. 18A and 18B are diagrams showing a light emitting state when a low voltage is applied, such as when starting light emission.

In the conventional light emitting device shown in FIG. 18A, since the threshold voltage at which light emission is started differs for each light emitting element row, only the light emitting element train having a low threshold voltage emits light, and the threshold voltage becomes high. High light emitting element rows do not emit light.

In the light emitting device 6 shown in FIG. 18B, the first light emitting element group 91 to the third light emitting element group 93 simultaneously start light emission by the mirror circuit formed by the first transistor 94 to the third transistor 96. Can be done.

(Modified example of the light emitting device according to the embodiment)
The light emitting devices 1 to 4 have a first light emitting element group 11 to a third light emitting element group 13 that emit green, blue, and red light, respectively, and the light emitting device according to the embodiment emits two or four or more lights. It may have a group of elements. For example, the light emitting device according to the embodiment may have two light emitting element groups that emit warm and cold colors, respectively, and four light emitting elements that emit amber light in addition to green, blue, and red. It may have a group.

Further, in the light emitting devices 1 to 4, the reference voltage generation circuit and the current control circuit are connected to the cathode of the LED in the final stage of the light emitting element group, but in the light emitting device according to the embodiment, the reference voltage generation circuit and the current control circuit are connected. May be connected to the anode of the first stage LED of the light emitting element group.

Further, in the light emitting device 2, the first light emitting element group 11 emits green light, the second light emitting element group 12 emits blue light, and the third light emitting element group 13 emits red light. In the light emitting device according to the embodiment, the colors emitted from the first light emitting element group 11 to the third light emitting element group 13 are not limited. In the light emitting device according to the embodiment, the first light emitting element group 11 emits blue light, the second light emitting element group 12 emits red light, and the third light emitting element group 13 emits green light. May be good. Further, the first light emitting element group 11 may emit red light, the second light emitting element group 12 may emit green light, and the third light emitting element group 13 may emit blue light.

Further, in the

light emitting devices

2 and 3, the first voltage dividing resistor 44 and the third voltage dividing resistor 46 and the first voltage dividing resistor 54 and the third voltage dividing resistor 56 are integrated, but the light emitting device according to the embodiment. Then, the variable resistor included in the reference voltage generation circuit may be formed separately.

Further, in the light emitting device 3, the variable resistance and the resistance ratio control circuit are arranged as separate elements, but in the light emitting device according to the embodiment, the variable resistance and the resistance ratio control circuit are used as an IC digital potentiometer or the like. It may be integrated.

Further, in the light emitting device 4, the reference voltage generation circuit 75 controls any two current values _{of the first current I 1,} the second current I ₂ and the third current I _{3 in order to adjust the color of the emitted light.} Generate a reference voltage to do so. However, in the light emitting device according to the embodiment, when the plurality of light emitting element trains emit light of the same color, the reference voltage generation circuit responds to the forward voltage of the plurality of light emitting element groups as in the light emitting device 5. A group of light emitting elements that control the current value may be determined.

In the light emitting device according to the embodiment, the reference voltage generation circuit does not control the current value of the current flowing through the light emitting element group having the highest forward voltage, but controls the current value of the current flowing through the other light emitting element group. The reference voltage generation circuit is a current control circuit arranged corresponding to a light emitting element group that controls the current value of the flowing current, and a current flowing in the light emitting element group having the lowest current flowing in the light emitting element string that controls the current value. Generate a reference voltage to match the current value of.

Further, the light emitting device 6 has a first light emitting element group 91 to a third light emitting element group 93, but the light emitting device according to the embodiment may have two or four or more light emitting element groups. Further, in the light emitting device according to the embodiment, the first transistor 94 to the third transistor 96 and the first switching element 97 to the third switching element 99 are the first-stage LEDs of the first light emitting element group 91 to the third light emitting element group 93. It may be connected to the anode of.

Further, in the light emitting device 6, the first switching element 97 to the third switching element 99 are formed so that the base and the collector of the first transistor 94 to the third transistor 96 can be short-circuited. However, in the light emitting device according to the embodiment, the plurality of switching elements may be formed so as to be able to release the space between the base and the collector of the plurality of transistors. The plurality of switching elements are released between the base and the collector of each of the plurality of transistors by, for example, cutting the wiring pattern forming the plurality of switching elements with a wiring pattern cutting device such as a laser irradiation device.

Claims

A pair of electrodes and
A group of first light emitting elements that emit light when a current is supplied from the pair of electrodes,
A second light emitting element group that is connected in parallel to the first light emitting element group and emits light when a current is supplied from the pair of electrode pairs.
The current values of the first current and the second current so that the current value of the first current flowing through the first light emitting element group and the current value of the second current flowing through the second light emitting element group have a predetermined ratio. A reference voltage generator that generates a reference voltage used to control one of them,
A current control circuit that controls one of the first current and the second current based on the reference voltage and does not control the other of the first current and the second current.
A light emitting device characterized by having.
The reference voltage includes a second reference voltage used to control the current value of the second current.
The current control circuit controls the second current based on the second reference voltage so that the current value of the second current becomes a predetermined ratio with respect to the current value of the first current. The light emitting device according to claim 1, further comprising a current control circuit.
The first light emitting element group emits light of the first color and emits light of the first color.
The light emitting device according to claim 2, wherein the second light emitting element group emits light of a second color different from the first color.
A third color that is connected in parallel to the first light emitting element group and the second light emitting element group and is different from any of the first color and the second color when a current is supplied from the pair of electrodes. A third light emitting element group that emits colored light,
Further, there is a third current control circuit that controls the third current so that the current value of the third current flowing through the third light emitting element group becomes a predetermined ratio with respect to the current value of the first current. death,
The light emitting device according to claim 3, wherein the reference voltage further includes a third reference voltage used for controlling the current value of the third current.
The reference voltage generation circuit has a second resistance pair connected in series with the first light emitting element group, and the voltage division voltage divided by the second resistance pair is used as the second reference voltage as the second current. The light emitting device according to claim 4, which outputs to a control circuit.
The light emitting device according to claim 5, wherein one of the resistors included in the second resistor pair is a variable resistor.
The second current control circuit is
The second switch, one end of which is connected to the light emitting element in the final stage of the second light emitting element group,
A second detection resistor with one end connected to the other end of the second switch,
The second switch is compared with the input second reference voltage and the second detection voltage applied to the second detection resistor so that the second reference voltage matches the second detection voltage. The second comparator that controls
The light emitting device according to claim 5 or 6.
The reference voltage generation circuit further has a third resistance pair connected in parallel to the second resistance pair, and the divided voltage divided by the third resistance pair is used as the third reference voltage as the third current. The light emitting device according to any one of claims 5 to 7, which outputs to a control circuit.
The light emitting device according to claim 8, wherein one of the resistors included in the third resistor pair is a variable resistor.
When the first light emitting element group, the second light emitting element group, and the third light emitting element group are connected in parallel and a current is supplied from the pair of electrode pairs, the first color and the second color are used. And a fourth light emitting element group that emits light of a fourth color different from any of the third colors, and
Further, there is a fourth current control circuit that controls the third current so that the current value of the fourth current flowing through the fourth light emitting element group becomes a predetermined ratio with respect to the current value of the first current. death,
The reference voltage further includes a fourth reference voltage used to control the current value of the fourth current.
The light emitting device according to claim 4, wherein the light of the first color is white.
The reference voltage generation circuit is
A first current control circuit capable of controlling the first current so that the current value of the first current becomes a predetermined ratio with respect to the current value of the second current.
A second current control circuit capable of controlling the second current so that the current value of the second current has a predetermined ratio to the current value of the first current is included.
The reference voltage generation circuit uses the reference voltage so that one of the first current and the second current has a predetermined ratio to the other current values of the first current and the second current. The light emitting device according to claim 1, which generates a voltage.
The first light emitting element group emits light of the first color and emits light of the first color.
The light emitting device according to claim 11, wherein the second light emitting element group emits light of a second color different from the first color.
The forward voltage of one of the first light emitting element group and the second light emitting element group whose current value is controlled is higher than the other forward voltage of the first light emitting element group and the second light emitting element group whose current value is not controlled. Also low,
The light emitting device according to claim 11, wherein the reference voltage generation circuit generates the reference voltage so that the current values of the first current and the second current become desired values.
A pair of electrodes and
A group of light emitting elements that are connected in parallel and emit light when a current is supplied from the pair of electrodes.
A plurality of transistors in which either a collector or an emitter is connected to each of the plurality of light emitting elements, and a plurality of transistors.
A switching element that short-circuits or releases between the base and collector of each of the plurality of transistors,
A light emitting device characterized by having.
One of the plurality of transistors is short-circuited between the base and the collector via the switching element, and the other transistors of the plurality of transistors are opened between the base and the collector via the switching element. The light emitting device according to claim 14.
The forward voltage of the light emitting element group connected in series to the transistor in which the base and the collector are short-circuited via the switching element is the light emitting element connected in series to the transistor in which the base and the collector are opened. The light emitting device according to claim 15, which is higher than the forward voltage of the group.
The reference voltage generation circuit has a second resistance pair connected in series to the first light emitting element group and a third resistance pair connected in parallel to the second resistance pair.
The resistance of each of the second resistance pair and the third resistance pair is a first contact connected to the other of the second resistance pair, a second contact connected to the other of the third resistance pair, and the above. A claim that is integrated by a resistor arranged between the first contact and the second contact, a movable contact that can be connected to an arbitrary location of the resistor, and a third contact that is connected to the movable contact. Item 4. The light emitting device according to item 4.
The operating member on which the internal gear is formed and
A rotating member having a columnar shaft portion, a first gear arranged at one end of the shaft portion and screwed into the internal gear, and a second gear arranged at one end of the shaft portion.
It has a third gear screwed into the second gear, and the ratio of the current flowing through the second light emitting element group to the ratio of the current flowing through the third light emitting element group according to the rotation of the third gear. The current adjuster that adjusts and
The light emitting device according to claim 17,
When the third gear rotates in response to the rotation of the operating member in the first direction, the movable contact moves so that the first voltage dividing resistance decreases and the third voltage dividing resistance increases. death,
When the third gear rotates in response to the rotation of the operating member in the second direction opposite to the first direction, the movable contact has the first partial pressure resistance increased and the third partial pressure. A luminaire that moves to reduce resistance.