Lighting System

Abstract

To provide an illumination system which can supply power source power to a light source body as well even when the number of light source bodies is increasing and a plurality of light source units are provided.SOLUTION: The illumination system includes: a plurality of light source bodies; a plurality of light source units each related to at least one of the light source bodies, the light source units supplying a power source voltage to their corresponding light source body; a voltage detection unit for detecting a power source voltage supplied to the light source body for every plural power source units; and a control unit for adjusting the power source voltage of each of the power source units according to the result of detection by the voltage detection unit.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present invention relates to a lighting system. [Background technology]

[0002] 2. Description of the Related Art Illumination devices capable of illuminating a wide area, such as when an object to be illuminated is long, are known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-205144 A Summary of the Invention [Problem to be solved by the invention]

[0004] When illuminating a wide area, such as when the object to be illuminated is long, it may be necessary to increase the number of light sources such as LEDs. As the number of light sources increases, the power supply to the light sources must also increase. However, in order to ensure a stable illuminance even when the number of light sources increases, the power supply must also be supplied stably.

[0005] The present invention has been made in consideration of the above-mentioned points. An object of the present invention is to provide a lighting system that can stably supply power to light source bodies even when the number of light source bodies is increased and a plurality of power supply units are provided. [Means for solving the problem]

[0006] The lighting system according to the present invention is characterized in that A plurality of light source substrates, each of which is equipped with at least one light source body; Each one At least two of the plurality of light source substrates A plurality of power supply units associated with the At least two light sources are mounted on the board. A plurality of power supply units for supplying a power supply voltage to the light source body; The power supply voltage supplied to the light source body is 、 The above For a selected light source substrate of the at least two light source substrates A voltage detection unit for detecting According to the detection result of the voltage detection unit, Accommodates at least two light source boards Power supply unit Electricity and a control unit that adjusts the source voltage. Effect of the Invention

[0007] Even when the number of light source bodies increases and a plurality of power supply units are provided, power supply power can be stably supplied to the light source bodies. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a functional block diagram showing functions of a lighting system 10 according to the present embodiment. [Diagram 2] FIG. 2 is a perspective view showing the appearance of the lighting device 300. [Diagram 3] FIG. 2 is a perspective view showing the configuration of an optical system of the illumination device 300. [Figure 4] 1A is a front view showing the configuration of one LED board 320, and FIG. 1B is a conceptual diagram showing the connection between the LEDs 322 on one LED board 320 and the power supply unit 100. FIG. [Diagram 5] 13 is a table showing the correspondence between the power supply unit 100, the power supply adjustment board 220, the LED board 320, and the channels of the LED board 320. [Figure 6] 2 is a functional block diagram showing the configuration of a power supply adjustment board 220. FIG. [Figure 7] 2 is a functional block diagram showing specific configurations of a ladder resistor section 222, a buffer circuit 224, and a constant current circuit 226. FIG. [Figure 8] 13 is a graph showing the relationship between the resistance indication value and the value of a current supplied to an LED 322. [Figure 9] 13 is a flowchart showing a drop / recovery detection process. [Figure 10] 13 is a table showing an example of a dimming value table. [Figure 11] 2 is a table showing an example of a configuration of the lighting system 10. [Figure 12] 13 is a flowchart showing an auto-voltage process. [Figure 13] 13 is a table showing the power supply adjustment board 220 monitoring the power supply voltage in the auto voltage process from the shortest state to the longest state of the lighting device 300. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] <<<<Outline of this embodiment>>>> <<Aspect 1-1>> According to aspect 1-1, a storage unit (such as a RAM of the power supply control board 210 described later) that stores a correspondence relationship (such as a dimming value table described later) between an adjustment value (such as a dimming value described later) for adjusting the brightness of light emitted from a light source (for example, the lighting device 300 described later and the LEDs 322 mounted on the first LED board 320-1 to the k-th LED board 320-k of the lighting device 300 described later) and a control value (such as a resistance instruction value described later) corresponding to the brightness; A driving unit (such as a ladder resistor unit 222 and a constant current circuit 226 described later) that generates a driving signal based on the control value of the correspondence relationship and supplies the driving signal to the light source; When there is a decrease region in which the brightness of the light emitted from the light source decreases as the adjustment value increases, a lighting system is provided that includes a control unit (such as a processor of a power supply control board 210 described later) that calibrates a control value corresponding to the decrease region, updates the correspondence between the adjustment value and the control value (e.g., Figure 10 described later), and generates the drive signal to the drive unit based on the control value of the updated correspondence.

[0010] The control value is determined by changing the combination of multiple resistors and switching the resistance value. By changing the combination of resistors, a drop region is more likely to occur. In particular, when the number of resistors whose current direction is reversed due to the change in the combination of resistors becomes a predetermined number (for example, three) or more, a drop region is more likely to occur. Furthermore, as the number of resistors whose current direction is reversed increases, the degree to which the brightness of the light decreases tends to become more noticeable. In the above example, a configuration in which the combination of multiple resistors is changed to switch the resistance value is shown, but this is not limited to this. This circuit divides the current by multiple resistors and controls the direction of each divided current by changing the combination of the multiple resistors. Therefore, it is sufficient that the control value is determined by dividing the current and controlling the direction of each divided current. For example, it is possible to make the circuit include a combination of impedance elements (capacitors and coils) and rectifying elements. It is sufficient that the control value is determined by dividing the current and controlling the direction of each divided current by this circuit.

[0011] The decrease region is different from the so-called variation. With variation, the target value may decrease or increase. Also, variation often has low reproducibility. In contrast, the decrease region is a region where reproducibility is high and the brightness of the light emitted from the light source decreases within a certain range of the adjustment value (a range corresponding to the number of resistors where the direction of the current is reversed).

[0012] The degraded area includes not only those that can be seen by the naked eye, but also those that can be detected by various detection devices such as sensors. In particular, in the case of a lighting device used for inspections such as surface inspection, the control value may be gradually changed in small increments according to various inspection conditions. Therefore, when a degraded area exists, it is easy to detect the degraded area when entering the degraded area from an area other than the degraded area in small increments. When a degraded area is detected, it is expected that the inspection may be stopped, or in some cases, it may be determined that the lighting device is defective, broken, or insufficiently adjusted. For this reason, it is preferable to process the degraded area in advance.

[0013] Furthermore, the correspondence between the adjustment values ​​and the control values ​​may be in the form of a table or an approximation such as a polynomial. The correspondence in the form of a table is a relationship in which a plurality of adjustment values ​​and a plurality of control values ​​are associated with each other on a one-to-one basis. By referring to the correspondence in the form of a table, it is possible to determine one control value from one adjustment value. The correspondence in the form of an approximation is a relationship that can be determined by determining the coefficient values ​​of the approximation. By referring to the approximation in which the coefficient values ​​are determined, it is possible to determine one control value from one adjustment value.

[0014] The correspondence relationship between the adjustment value and the control value may be any relationship that allows the control value to be uniquely determined from the adjustment value, or conversely, allows the adjustment value to be uniquely determined from the control value, if necessary.

[0015] The light source may be any device or component that emits light. It is preferable that the light source is composed of at least one solid-state light source. A solid-state light source is a device that excites a solid (substance) by supplying it with energy such as electrical energy, and emits light that is specific to the substance. Examples of solid-state light sources include light-emitting diodes (LEDs), semiconductor lasers (LDs), and organic electroluminescence (OELs).

[0016] Calibration refers to correcting a value that differs from an originally planned value. In this case, calibration may be any process that brings a value closer to the originally planned value, even if only slightly.

[0017] When the brightness of the light from the light source may become darker as the adjustment value increases, the control value is calibrated within the range in which the brightness becomes darker. Therefore, the brightness can be adjusted without causing the user to feel uncomfortable.

[0018] <<First and second aspects>> The first-2 aspect is the same as the first-1 aspect, The control unit calibrates the control value so that the brightness of the light emitted from the light source becomes constant or brighter as the adjustment value increases (for example, the graph in FIG. 8 and the process in FIG. 9 described later).

[0019] For example, in the decrease region, as the adjustment value increases, the control value is calibrated by making the control value constant or increasing the control value. In this way, by calibrating the control value, the brightness of the light is made constant or gradually brightened.

[0020] As the adjustment value increases, the brightness of the light is calibrated to be constant, or the brightness of the light is calibrated to be gradually brighter. In this way, the user does not feel uncomfortable.

[0021] <<First to third aspects>> The first-third aspect is the first-second aspect, The driving unit has a ladder resistor (such as ladder resistor unit 222 (FIG. 7, etc.) described later) having a plurality of resistor elements connected in series, a current flowing through each of the plurality of resistance elements is determined by the control value; The ladder resistor outputs a voltage signal having a voltage value corresponding to a current flowing through each of the plurality of resistive elements (for example, a dimming voltage signal shown in FIG. 7 to be described later), The drive section includes a conversion section (such as a constant current circuit 226 described later) that converts the voltage signal into the drive signal (for example, a constant current described later).

[0022] When the number of resistor elements in which the current direction is reversed among the multiple resistor elements constituting the ladder resistor changes by a predetermined number (for example, 3) or more due to a change in the adjustment value, a lowering region is more likely to occur. As described above, since the correspondence between the adjustment value and the control value is updated, even when a ladder resistor is used, the brightness can be appropriately adjusted by using the updated correspondence.

[0023] Since a ladder resistor is used, a voltage signal can be generated without requiring signal conversion processing, and the voltage signal can be generated quickly from an adjustment value, so that the brightness can be switched in a short time and the brightness can be switched without causing a sense of discomfort to the user.

[0024] <<First to fourth aspects>> The first to fourth aspect is the first to third aspect, Further, a power supply unit (e.g., power supply units 100-1 to 100-m described later) is provided to supply a power supply voltage to the light source. The light source includes a plurality of light source substrates (for example, a first LED substrate 320-1 to a k-th LED substrate 320-k, which will be described later), Each of the plurality of light source boards is equipped with a plurality of light source bodies (e.g., LEDs 322, which will be described later), In each of the plurality of light source substrates, the plurality of light source bodies are divided into a plurality of groups (for example, a substrate region 1-1 to a substrate region 2-3, which will be described later, and the like) and arranged; A power supply voltage is supplied in parallel to each of the plurality of groups.

[0025] The light source body is preferably a single or multiple solid-state light source.

[0026] Each of the light source boards has a plurality of light source bodies mounted thereon. In order to connect all the light source bodies mounted on the light source board in series and apply a power supply voltage to the series-connected light source bodies to cause all of the light source bodies to emit light, it is necessary to apply a large voltage according to the required brightness. For this reason, there is a possibility that a power supply unit having specifications capable of outputting the desired large power supply voltage must be found, selected, or newly manufactured.

[0027] In response to this, by dividing multiple light source bodies into multiple groups, connecting the groups in parallel and supplying a power supply voltage to each group, the size can be made smaller than when all the light source bodies belonging to the multiple groups are connected in series.

[0028] The number of LEDs 322 belonging to each group may be the same for all groups, or some may be different. It may be determined appropriately according to the shape and size of the object to be illuminated, the lighting conditions, etc. The groups may be a convenient division for control by the control unit or for the power supply voltage of the power supply unit. It may be divided so that the control unit can control each group separately.

[0029] In addition, the first to fourth aspects are as follows: The light source includes a plurality of light source bodies and a plurality of light source substrates each having at least two of the light source bodies mounted thereon; Further, a power supply unit is provided to supply a power supply voltage to the light source body. In each of the plurality of light source boards, the light source bodies mounted on the light source board are grouped in units of a predetermined number, and each of the plurality of light source boards has a plurality of groups; The control unit may supply power in parallel for each of the groups in each of the plurality of light source boards, and supply a power supply voltage from the power supply unit to the light source elements belonging to the group.

[0030] <<First to fifth aspects>> The first to fifth aspects are the same as the first to fourth aspects, The control unit calibrates a control value corresponding to the decline region using a light source body belonging to at least one of the multiple groups, shares the updated correspondence among the multiple groups, and causes the drive unit to generate the drive signal.

[0031] Since calibration is performed using light source elements belonging to at least one group, the process of generating the correspondence between the adjustment values ​​and the control values ​​can be simplified and the configuration can be simplified.

[0032] <<Aspects 1-6>> The first to sixth aspect is the first to fourth aspect, The ladder resistors correspond to each of a plurality of light source boards, The ladder resistor outputs a voltage signal having the one voltage value in common to the plurality of groups of each of the plurality of light source boards.

[0033] By sharing the ladder resistor among multiple groups, the tendency of the drop area occurring in each of the multiple groups sharing the ladder resistor can be made common, the process of generating the correspondence between the adjustment value and the control value can be reduced, the configuration can be simplified, and it is easy to make the device smaller. Furthermore, heat generation from the ladder resistor can be suppressed.

[0034] <<Aspects 1-7>> According to the first to seventh aspects, a storage unit (such as a RAM of the power supply control board 210 described later) that stores a correspondence relationship (such as a dimming value table described later) between an adjustment value (such as a dimming value described later) for adjusting the brightness of light emitted from a light source (for example, the lighting device 300 described later and the LEDs 322 mounted on the first LED board 320-1 to the k-th LED board 320-k of the lighting device 300 described later) and a control value (such as a resistance instruction value described later) corresponding to the brightness; A driving unit (such as a ladder resistor unit 222 and a constant current circuit 226 described later) that generates a driving signal based on the control value of the correspondence relationship and supplies the driving signal to the light source; When there is a decrease region in which the brightness of the light emitted from the light source decreases as the adjustment value increases, a lighting control device is provided that includes a control unit (such as a processor of a power supply control board 210 described later) that calibrates a control value corresponding to the decrease region, updates the correspondence between the adjustment value and the control value (e.g., Figure 10 described later), and generates the drive signal to the drive unit based on the control value of the updated correspondence.

[0035] The same configuration and processing can be applied not only to the lighting system according to the aspect 1-1 but also to the lighting control device according to the aspect 1-7. It is possible to provide a lighting control device that can adjust the brightness without making the user feel uncomfortable.

[0036] <<Aspect 2-1>> According to aspect 2-1, A plurality of light sources (e.g., LEDs 322, which will be described later), A plurality of power supply units (e.g., a power supply unit 100 described later) each of which is associated with at least one of the light source bodies and supplies a power supply voltage to the associated light source body; a voltage detection unit (e.g., a power supply control board 210, which will be described later) that detects the power supply voltage supplied to the light source body for each of the plurality of power supply units; a control unit (for example, a power supply adjustment board 220 described later) that adjusts a power supply voltage of each of the plurality of power supply units according to a detection result of the voltage detection unit.

[0037] The power supply units are associated with the light source bodies. The voltage detection unit detects a power supply voltage supplied to the light source body for each of the power supply units. The control unit adjusts the power supply voltage of each of the power supply units using the detection result of the voltage detection unit.

[0038] Since the power supply voltage is adjusted for each of the multiple power supply units, the power supply voltage can be adjusted to an appropriate level depending on the lighting conditions.

[0039] <<Aspect 2-2>> The second aspect of the present invention is the same as the second aspect of the present invention, The control unit adjusts the power supply voltage of one of the multiple power supply units and the power supply voltage of at least one other power supply unit different from the one power supply unit (e.g., step S1217 in Figure 12 described later), and then adjusts the power supply voltage of the other power supply unit (e.g., step S1227 in Figure 12 described later).

[0040] First, the power supply voltages of the multiple power supply units are adjusted to perform coarse adjustment, and then the power supply voltages of the power supply units are individually adjusted to perform fine adjustment. By performing the coarse adjustment in advance, the time required for fine adjustment can be shortened.

[0041] Furthermore, in the case of a lighting system in which the number of power supply units can be changed, the power supply voltage can be adjusted according to the installed power supply units, so that an appropriate power supply voltage can be obtained.

[0042] <<Second and third aspects>> The second-third aspect is the second-first aspect, Further, the light source device includes a plurality of light source substrates (for example, a first LED substrate 320-1 to a k-th LED substrate 320-k described later) each having at least two of the light source bodies mounted thereon, In each of the plurality of light source boards, the mounted light source bodies are grouped according to a predetermined number, and each of the plurality of light source boards has a plurality of groups for each of the plurality of light source boards (for example, board area 1-1 to board area 2-3 shown in FIGS. 4(a) and 4(b) , etc.), In each of the plurality of light source substrates, the plurality of groups are configured in parallel (for example, substrate region 1-1 to substrate region 2-3 shown in FIGS. 4(a) and 4(b)), A power supply voltage is supplied to the light source elements belonging to the group (for example, a configuration shown in FIG. 4(a) to be described later).

[0043] Since the power supply voltage is divided and supplied in parallel for each of the multiple groups, the power supply voltage can be made smaller than when the power supply voltage is supplied to a state in which all the light source elements belonging to the multiple groups are connected in series.

[0044] <<Second to fourth aspects>> The second-fourth aspect is the second-third aspect, the plurality of power supply units are associated with the plurality of light source boards, Each of the multiple power supply units is connected in parallel to the multiple groups on the associated light source board, and supplies a power supply voltage to the light source bodies belonging to each of the multiple groups (for example, the configuration shown in Figures 4(a) and (b) described below).

[0045] By connecting a plurality of power supply units to the corresponding light source boards, a power supply voltage can be supplied to the light source elements belonging to each group of a plurality of light source boards, thereby simplifying the configuration.

[0046] <<Aspects 2-5>> The second-fifth aspect is the second-third aspect, At least two light source bodies belong to each of the plurality of groups, and in each of the plurality of groups, the at least two light source bodies are electrically connected in series (for example, the configuration shown in Figures 4(a) and (b) described below).

[0047] <<Aspects 2-6>> The second-sixth aspect is the second-fourth aspect, The display device further includes a housing (such as housing 310 described later) having a first housing area (such as an area in which LED substrates 320-1 to 320-18 in FIG. 5 described later are housed) capable of housing the plurality of light source substrates, and a second housing area different from the first housing area (such as an area in which LED substrates 320-19 to 320-20 in FIG. 5 described later are housed), the second accommodation area is an accommodation area used when adding light source substrates in excess of a first maximum accommodation number that can be accommodated in the first accommodation area, When one light source board is accommodated in the second accommodating area, one of the multiple power supply units supplies a power supply voltage to a light source body mounted on any of the light source boards (e.g., LED boards 320-1 to 320-18 in Figure 5 described later) accommodated in the first accommodating area, and also supplies a power supply voltage to a light source body mounted on the one light source board (e.g., LED boards 320-19 and to 320-20 in Figure 5 described later) (e.g., supplying a power supply voltage to the light source bodies of channels 37 to 40 in Figure 5 described later).

[0048] A power supply voltage from one power supply unit is distributed and supplied to both the light source body of the light source board accommodated in the first accommodation area and the light source body of the light source board accommodated in the second accommodation area. The one power supply unit is shared by both the light source body of the light source board accommodated in the first accommodation area and the light source body of the light source board accommodated in the second accommodation area.

[0049] Even when a light source board is added, a single power supply unit can be shared to supply a power supply voltage to the additional light source board without adding a power supply unit, so that the light source board can be added simply and easily. When the power supply unit has a surplus power supply voltage, the surplus power supply voltage of the power supply unit can be effectively utilized.

[0050] Furthermore, it is preferable that the "plurality of power supply units" refers to a state in which the maximum number of power supply units that can be mounted is installed. Even in a state in which it is not possible to increase the number of power supply units, it is possible to supply a power supply voltage to the added light source board.

[0051] <<Aspects 2-7>> The second-seventh aspect is the second-sixth aspect, In addition to the one power supply unit, a power supply voltage is supplied to the light source body mounted on the one light source substrate from another power supply unit among the plurality of power supply units that is different from the one power supply unit (for example, supply of power supply voltage to channels 37 to 40 in Figure 5 described later).

[0052] A power supply voltage is supplied to the light source body mounted on one light source board not only from one power supply unit but also from other power supply units. In this way, even if the power supply voltage of each power supply unit is lowered by an amount corresponding to a margin, the power supply voltage required for the light source body of one light source board can be accurately supplied.

[0053] <<Aspects 2-8>> According to the second to eighth aspects, A plurality of power supply units (e.g., a power supply unit 100, etc., described later) each of which is associated with at least one of a plurality of light source bodies (e.g., an LED 322, etc., described later) and supplies a power supply voltage to the associated light source body; a voltage detection unit (e.g., a power supply control board 210, which will be described later) that detects the power supply voltage supplied to the light source body for each of the plurality of power supply units; A control unit (for example, a power supply adjustment board 220 described later) that adjusts the power supply voltage of each of the plurality of power supply units according to a detection result of the voltage detection unit is provided.

[0054] The same configuration and processing can be applied not only to the lighting system according to the aspect 2-1 but also to the lighting control device according to the aspect 2-8. Since the power supply voltage is adjusted for each of the multiple power supply units, the power supply voltage can be adjusted to an appropriate level according to the lighting conditions.

[0055] <<<<<<Details of this embodiment>>>>> Hereinafter, an embodiment will be described with reference to the drawings.

[0056] <<<<Configuration of lighting system 10>>>> FIG. 1 is a functional block diagram showing the configuration of a lighting system 10 according to the present embodiment.

[0057] The lighting system 10 according to the present embodiment includes a power supply unit 100, a power supply control unit 200, and a lighting device 300. In the lighting system 10 according to the present embodiment, the power supply unit 100, the power supply control unit 200, and the lighting device 300 are configured separately and are electrically connected to each other by a harness 350 (see FIG. 2 ) or the like. The power supply unit 100 supplies a power supply voltage to the lighting device 300 via the harness 350. Various commands, information, and the like are transmitted and received between the power supply control unit 200 and the lighting device 300 via the harness 350.

[0058] The lighting system 10 may be used as a lighting system for surface inspection. The object of the surface inspection (hereinafter, the lighting object) may be small or large. Therefore, the length of the harness 350 varies depending on the usage environment such as the inspection environment of the lighting system 10. For example, the length of the harness 350 may be as short as less than 1 meter and as long as 50 meters or more. Therefore, in the lighting system 10 according to the present embodiment, there may be cases where the voltage drop of the power supply voltage caused by the harness 350 cannot be ignored. It is preferable that the lighting system 10 can appropriately change the power supply voltage of the power supply unit 100 according to the voltage drop caused by the harness 350.

[0059] Furthermore, when the lighting device 300 itself is long, there are cases where the voltage drop of the power supply voltage cannot be ignored even for optical elements located far from the power supply. Therefore, even in the case of a long lighting device 300, it is preferable to use a lighting system 10 that can appropriately change the power supply voltage of the power supply unit 100 in response to the voltage drop.

[0060] The lighting system 10 according to the present embodiment has a power supply unit 100, a power supply control unit 200, and a lighting device 300 as separate components. For example, it may be necessary to replace any of them due to a breakdown or change over time. The replacement may change the optical and electrical characteristics of the circuit components and optical elements of the power supply unit 100, the power supply control unit 200, and the lighting device 300, and may require a change in the power supply voltage of the power supply unit 100. In such a case, it is preferable to use a lighting system 10 that can appropriately change the power supply voltage of the power supply unit 100. Even if the combination of the power supply unit 100, the power supply control unit 200, and the lighting device 300 is changed, it is possible to provide a lighting system 10 whose brightness and characteristics do not change from before the change.

[0061] Furthermore, in the case of current control of the lighting device 300, which requires a large current, it is preferable to use a linear constant current circuit in order to stably drive light emitting elements even at low illuminance. Also, it is preferable for the linear constant current circuit to use a FET that can generate a constant current, but the FET has the problem of being prone to heat generation.

[0062] Furthermore, it is preferable to use a highly efficient switching power supply as the power supply for driving the light emitting element. By adjusting this switching power supply to an optimal voltage, it is possible to provide a lighting device that can minimize heat generation.

[0063] <<<Power supply unit 100 (power supply units 100-1, ..., 100-m)>>> The power supply unit 100 is a power supply for driving the light source (LED (Light Emitting Diode) 322 described later). The power supply unit 100 is connected to an LED board 320 (described later) on which the LEDs 322 are mounted, and supplies a power supply voltage to the LED board 320. The power supply unit 100 mainly has a switching power supply (not shown) and the like, rectifies power from a commercial power supply, and outputs a constant DC power supply voltage. The power supply unit 100 may have a linear power supply instead of a switching power supply, as long as it can supply a constant power supply voltage to the LED board 320. Note that the power supply unit 100 may be a device having a circuit that can adjust a predetermined input power to the power supply power required for the LEDs 322 to emit light, as well as a commercial power supply, and can supply the power.

[0064] The power supply unit 100 is composed of at least one. The number of power supply units 100 is determined according to the current value required by the LEDs 322, the number of LEDs 322, and the like. The number of power supply units 100 may be determined from the current value of the LEDs 322 required when the light emitted from the LEDs 322 is the brightest, for example, when the illuminance of the light emitted from the LEDs 322 is the highest. The number of the LEDs 322 (the number of the LED boards 320) may be determined according to the size (length, etc.) of the illumination object illuminated by the light emitted from the illumination device 300.

[0065] 1, the lighting system 10 includes m power supply units 100-1 to 100-m. For example, m is a natural number such as 10. The power supply units 100-1 to 100-m all have the same configuration and function. In the following, when there is no need to distinguish between the power supply units 100-1 to 100-m, they will be simply referred to as power supply units 100.

[0066] The power supply unit 100 of the lighting system 10 according to this embodiment supplies a power supply voltage for driving the LED substrate 320, but does not supply a power supply voltage for driving the power supply control unit 200 described below. In this manner, a power supply voltage can be stably supplied to the LED substrate 320, regardless of the configuration or state of the power supply control unit 200. Without being limited to this configuration, the power supply unit 100 may supply a power supply voltage to both the LED substrate 320 and the power supply control unit 200. This simplifies the configuration of the entire lighting system 10.

[0067] The power supply voltage (Vpp1 to Vppm (see FIG. 1)) supplied from the power supply unit 100 to the LED board 320 is also supplied to the power supply control unit 200. As described above, the power supply voltage also supplied to the power supply control unit 200 is not for driving the power supply control unit 200, but for determining whether the power supply voltage supplied to the LED board 320 is appropriate. The power supply control board 210 (described later) of the power supply control unit 200 determines whether the voltage value of the supplied power supply voltage is within an appropriate range. The processor of the power supply control board 210 can determine whether a power supply voltage of an appropriate voltage value is being supplied to the LED board 320.

[0068] 1, the power supply voltage supplied from the power supply unit 100-1 is indicated as Vpp1, the power supply voltage supplied from the power supply unit 100-i as Vppi, and the power supply voltage supplied from the power supply unit 100-m as Vppm. The power supply voltages Vpp1 to Vppm supplied to the power supply control unit 200 are supplied to the ADC of the power supply control board 210 and converted into digital signals.

[0069] In the present embodiment, the power supply voltage to be supplied to the LED substrate 320 is supplied to the power supply control unit 200 on the way from the power supply unit 100 to the LED substrate 320. However, the present invention is not limited to this, and the power supply voltage actually supplied to the LED substrate 320 may be supplied to the power supply control unit 200. The voltage value of the power supply voltage actually supplied to the LED substrate 320 can be determined.

[0070] <<<Power Supply Control Unit 200>>> As shown in FIG. 1, the power supply control unit 200 includes a power supply control board 210 and at least one power supply adjustment board 220.

[0071] <<Power supply control board 210>> The power supply control board 210 has a processor (such as a CPU (Central Processing Unit)), a ROM (Read Only Memory), a RAM (Random Access Memory), an I / O (Input / Output Interface), a communication I / F (Communication Interface Device), an FPGA (Field Programmable Gate Array), etc. (not shown).

[0072] <Processor> The processor executes various processes for controlling the LEDs 322 of the lighting device 300 (to be described later) and the power supply voltage of the power supply unit 100. For example, the processor executes the processes shown in Figs. 9 and 12 (to be described later).

[0073] <rom> The ROM stores various programs and constants for executing various processes (eg, the processes in FIG. 9 and FIG. 12).

[0074] <ram> The RAM temporarily stores variables and other values ​​used when the program is executed. The RAM also stores a dimming value table for determining the resistance instruction value from the dimming value. The dimming value table will be described later.

[0075] The I / O is connected to an ADC (analog-digital conversion circuit) (not shown), a DAC (digital-analog conversion circuit) (not shown), etc. The power supply control board 210 inputs and outputs various digital data between the ADC (analog-digital conversion circuit) (not shown), the DAC (digital-analog conversion circuit) (not shown), etc. via the I / O.

[0076] In this embodiment, the ADC is mainly supplied with the voltage value of the power supply voltage supplied from the power supply unit 100 to the LED substrate 320, the current value of the power supply current supplied to the LEDs 322 of the LED substrate 320 (the voltage value converted into a voltage value), and the like. The processor of the power supply control substrate 210 can determine whether the voltage value of the power supply voltage supplied to the LED substrate 320 and the current value of the power supply current supplied to the LEDs 322 are appropriate or not, and control the power supply unit 100. The detection process of the power supply voltage will be described later.

[0077] <Communication I / F> The communication I / F is connected to an external control device (not shown) (such as a personal computer). The power supply control board 210 inputs and outputs various commands and data between the external control device and the power supply control board 210 via the communication I / F. The communication I / F may be connected to the external control device via a network or the like.

[0078] <fpga> The FPGA stores various digital circuits required by the power supply control board 210. For example, the FPGA detects the presence or absence of a power supply adjustment board 220, which will be described later, and stores the detection result.

[0079] <Operation section> The power supply control board 210 has an operation unit (not shown) that can be operated by an operator. The operator can set various conditions such as lighting conditions by operating the operation unit. For example, the operator can set a dimming value by operating the dimming on the operation unit. The dimming operation is an operation for determining (adjusting) the brightness of the light emitted from the LED 322. The dimming value is a value for determining the brightness of the light emitted from the LED 322. The power supply adjustment board 220 determines the power supply current to be supplied to the LED 322 based on the dimming value. Details will be described later.

[0080] The power supply control board 210 may receive the dimming value from an external control device (not shown) such as a personal computer. The external control device determines the dimming value, and the power supply control board 210 receives the dimming value via the communication I / F. In this case, the power supply adjustment board 220 also determines the power supply current to be supplied to the LED 322 based on the dimming value.

[0081] The processor of the power supply control board 210 refers to the dimming value table stored in the RAM, determines a resistance command value from the dimming value, and transmits the resistance command value to the power supply adjustment board 220.

[0082] <<Dimming value and resistance indication value>> <Dimming and dimming value> Dimming refers to adjusting the brightness of light emitted from the LED 322 of the lighting device 300. The dimming value is a value associated with the brightness of light emitted from the LED 322. When the dimming value is small, the LED 322 emits dim light, and when the dimming value is large, the LED 322 emits bright light. The dimming value may be an analog value or a digital value. In the case of an analog value, the dimming value can be represented by the magnitude of a voltage, etc. In the case of a digital value, the dimming value can be represented by a numerical value within a range that can be expressed by a predetermined number of quantization bits.

[0083] In this embodiment, the dimming value is a digital value (quantized dimming value) that can be processed by the power supply control board 210. The dimming value is converted into a resistance instruction value by referring to a dimming value table (FIG. 10 described later). The resistance instruction value is a digital value for generating a current to be supplied to the LED 322, and is a value for specifying the brightness of the light emitted from the LED 322.

[0084] <Linearity between dimming value and brightness (illuminance)> The LED 322 emits light with a brightness according to the magnitude of the supplied current. A light-emitting element such as a light-emitting diode may have a characteristic that the brightness of the light does not change linearly with respect to the magnitude of the supplied current. However, from the viewpoint of ease of adjustment and control, by forming a relationship in which the brightness (illuminance) of the emitted light changes linearly with the dimming value, it becomes easier to control the brightness of the light from the dimming value.

[0085] <Dimming value table> The dimming value table is a table for converting dimming values ​​into resistance command values ​​(see FIG. 10 described later). In lighting system 10 according to the present embodiment, the resistance command value is a value for specifying the potential of resistors constituting ladder resistor section 222 (see FIG. 6 and FIG. 7 described later). The resistance command value determines a combined resistance value constituting ladder resistor section 222, and determines the current value of the current supplied to LED 322. A signal indicating the resistance command value is a digital signal, and is supplied to nodes 230-1 to 230-12 (see FIG. 7) described later. The dimming value is specifically a digital value for determining the value of the current supplied to LED 322 via the resistance command value, and is a value for specifying the brightness of the light emitted from LED 322.

[0086] The dimming value table is a table in which resistance instruction values ​​are assigned in advance to dimming values ​​so that there is linearity between the dimming value and the illuminance (see FIG. 10). By referring to the dimming value table, it is possible to convert the dimming value into a resistance instruction value having a linear relationship. In other words, it is possible to determine a resistance instruction value that changes linearly (for example, proportionally) with respect to changes in the dimming value.

[0087] The dimming value table can be formed by measuring the illuminance of light emitted from the LED 322 in advance. The dimming value table can be generated by measuring a plurality of different brightnesses (illuminances) of the LED 322 in advance, and associating the dimming values ​​corresponding to each of the plurality of illuminances with the resistance instruction values ​​that result in the illuminances and storing them in advance in the RAM. The brightness of the LED 322 can be measured using a light meter or the like. The generation of the dimming value table will be described later in detail.

[0088] In the lighting system 10 according to the present embodiment, the dimming value table is generated and stored in the RAM before shipping the lighting system 10. Note that the dimming value table may be appropriately calibrated even after the lighting system 10 is shipped and becomes operable.

[0089] <Percentage dimming value and quantized dimming value> In this embodiment, a percentage dimming value and a quantized dimming value are used as the dimming value. The percentage dimming value is a dimming value expressed as a percentage. The percentage dimming value is a value from 0 to 100%. When the percentage dimming value is 0%, the LED 322 is turned off. When the percentage dimming value is 100%, the LED 322 is turned on most brightly. The most brightly lit state may be any state that can be controlled and is brighter than the required brightness. The quantized dimming value can express the dimming value by a numerical value (zero and a positive integer in this embodiment) within a range that can be expressed by a predetermined quantization bit rate. When the quantization bit rate is 10 bits, the quantized dimming value is any one of 1024 values ​​from 0 to 1023. When the quantization bit rate is 8 bits, the quantized dimming value is any one of 256 values ​​from 0 to 255.

[0090] The percentage dimming value and the quantized dimming value can be associated with each other. For example, when the number of quantized bits is 10 bits, the correspondence is as follows. A percentage dimming value of 0% corresponds to a quantized dimming value of 0. A percentage dimming value of 25% corresponds to a quantized dimming value of 256. A percentage dimming value of 50% corresponds to a quantized dimming value of 512. A percentage dimming value of 75% corresponds to a quantized dimming value of 768. A percentage dimming value of 100% corresponds to a quantized dimming value of 1023. Hereinafter, in the case of normal dimming, the quantized dimming value when the percentage dimming value is 100% is referred to as the maximum quantized dimming value.

[0091] <Generating a dimming value table> The procedure for generating the dimming value table will now be described.

[0092] First, the quantized dimming value and the resistance instruction value are associated when the LED 322 emits light with an illuminance of 100% as a percentage dimming value. The illuminance when the percentage dimming value is 100% is set as the reference illuminance for generating the dimming value table.

[0093] Next, the dimming value is decreased to detect the illuminance at which the illuminance of the light emitted from the LED 322 is 75% of the reference illuminance. The quantized dimming value at which the illuminance is 75% of the reference illuminance is associated with the resistance instruction value.

[0094] Furthermore, the dimming value is decreased to detect the illuminance at which the illuminance of the light emitted from the LED 322 becomes 50% of the reference illuminance. The quantized dimming value at which the illuminance becomes 50% of the reference illuminance is associated with the resistance instruction value.

[0095] Similarly, the quantized dimming value and the resistance instruction value are associated when the illuminance of the light emitted from the LED 322 is 25% of the reference illuminance. The quantized dimming value and the resistance instruction value are associated when the illuminance of the light emitted from the LED 322 is 1% of the reference illuminance.

[0096] In this manner, the quantized dimming value and the resistance instruction value can be associated with each other for illuminance of 1%, 25%, 50%, 75%, and 100% of the reference illuminance.

[0097] <Interpolation of resistance readings> For each of illuminance levels of 1%, 25%, 50%, 75%, and 100% of the reference illuminance, from five relationships that associate quantized dimming values ​​with resistance command values, resistance command values ​​that correspond to the entire range of quantized dimming values ​​from 0 to 1023 are determined by interpolation calculation. Note that the interpolation calculation may also be performed for resistance command values ​​in a range where resistance command values ​​are not associated with quantized dimming values.

[0098] Specifically, the resistance instruction values ​​are determined as follows. The resistance instruction values ​​in the range of quantized dimming values ​​21 to 255 are determined by linear interpolation approximation from two resistance instruction values, the resistance instruction value for quantized dimming value 1 and the resistance instruction value for quantized dimming value 256. The resistance instruction values ​​in the range of quantized dimming values ​​257 to 511 are determined by linear interpolation approximation from two resistance instruction values, the resistance instruction value for quantized dimming value 256 and the resistance instruction value for quantized dimming value 512. The resistance instruction values ​​in the range of quantized dimming values ​​513 to 766 are determined by linear interpolation approximation from two resistance instruction values, the resistance instruction value for quantized dimming value 512 and the resistance instruction value for quantized dimming value 767. The resistance command value in the range of quantized dimming value 768 to 1022 is determined from two resistance command values, the resistance command value of quantized dimming value 768 and the resistance command value of quantized dimming value 1023, by linear interpolation approximation.

[0099] <Power adjustment board 220> The power supply adjustment board 220 is connected to the power supply control board 210 so as to be able to transmit and receive the resistance indication value transmitted from the power supply control board 210.

[0100] As shown in FIG. 6, the power supply adjustment board 220 mainly includes: A ladder resistor section 222; A buffer circuit 224; A constant current circuit 226; has.

[0101] 1, the lighting system 10 has n power supply adjustment boards 220-1 to 220-n. The power supply adjustment boards 220-1 to 220-n all have the same configuration and function. The number of power supply adjustment boards 220 is determined according to the number of LED boards 320. In the following, when there is no need to distinguish between the power supply adjustment boards 220-1 to 220-n, they will simply be referred to as power supply adjustment boards 220. The specific configuration and function of the power supply adjustment boards 220 will be described in detail later.

[0102] <<<Lighting device 300>>> Fig. 2 is a perspective view showing the appearance of the illumination device 300. Fig. 3 is a perspective view showing the configuration of the optical system of the illumination device 300.

[0103] As shown in Fig. 2 and Fig. 3, the illumination device 300 has an elongated shape. The illumination device 300 has a length according to the size (length, etc.) of an object to be illuminated. The object to be illuminated can be, for example, an object to be inspected for inspecting a surface. The illumination device 300 has an opening 312 from which light is emitted. The illumination device 300 emits light of a wavelength according to the content of the inspection of the object to be inspected through the opening 312, and illuminates the object to be inspected.

[0104] The lighting device 300 has a housing 310. The housing 310 mainly contains a plurality of LED boards (light emitting boards) 320, a condenser lens 330, and a diffuser lens (diffusion plate) 340 as an optical system.

[0105] <Housing 310> The housing 310 houses various components of the lighting device 300. The housing 310 has an elongated groove-like shape. The housing 310 has an opening 312. The opening 312 has an elongated slit-like (elongated cut or gap) shape.

[0106] <LED substrate 320> The lighting device 300 has at least one LED substrate 320. The number of LED substrates 320 may be appropriately determined according to the size (length, etc.) of the object to be illuminated. The LED substrate 320 is composed of an aluminum substrate and has a thin plate-like elongated rectangular shape. A plurality of LEDs 322 are mounted on the LED substrate 320. For example, 72 LEDs 322 are mounted on each of the LED substrates 320 (see FIG. 4). The plurality of LEDs 322 are arranged in a straight line in a row along the longitudinal direction of the LED substrate 320.

[0107] The plurality of LEDs 322 may be arranged in a curved shape on the LED substrate 320. There may be a plurality of rows of LEDs 322 arranged in the longitudinal direction of the LED substrate 320. The plurality of LEDs 322 are preferably arranged parallel to each other along the longitudinal direction of the LED substrate 320.

[0108] The LED substrate 320 does not have a power supply unit and a control unit. Note that the LED substrate 320 may have various sensors such as temperature detection.

[0109] <led322> The LED 322 is a light-emitting diode for emitting light from the lighting device 300. The LED 322 emits light of a predetermined wavelength. The LED 322 emits, for example, visible light such as white light or infrared light. The LED 322 may be any light-emitting diode capable of emitting light of a desired color (wavelength, etc.) at a desired brightness (illuminance) according to an object to be illuminated.

[0110] In the example shown in FIG. 1, the lighting system 10 includes k LED boards 320-1 to 320-k. The LED boards 320-1 to 320-k basically have the same configuration and function. Some of the LED boards 320-1 to 320-k may have different configurations and functions. Hereinafter, when there is no need to distinguish between the LED boards 320-1 to 320-k, they will be simply referred to as LED boards 320. The configuration and function of the LED boards 320 will be described in detail later.

[0111] <Condenser lens 330> The condenser lens 330 is a lens that condenses the light emitted from the LED 322. The condenser lens 330 is made of acrylic and has a long, solid cylindrical (rod-like, bar-like) shape. The condenser lens 330 may be molded from glass or other resins. The condenser lens 330 may also have a hollow cylindrical shape as long as it can condense light. Furthermore, the condenser lens 330 is preferably heat-resistant and rigid.

[0112] The condenser lens 330 is disposed at a position separated from the LEDs 322 such that a direction L1 in which the LEDs 322 are arranged and a central axis L2 of the condenser lens 330 are parallel to each other.

[0113] <Diffuser Lens 340> The diffuser lens (diffusion lens) 340 is a diffusion plate for diffusing the light transmitted through the condenser lens 330. The entire diffuser lens 340 has an elongated thin plate or film shape.

[0114] The diffuser lens 340 is disposed along the longitudinal direction. Specifically, the diffuser lens 340 is disposed at a position separated from the condenser lens 330 and such that the central axis L3 of the diffuser lens 340 is parallel to the central axis L2 of the condenser lens 330. Note that it is preferable that the direction L1 in which the LEDs 322 are arranged, the central axis L2 of the condenser lens 330, and the central axis L3 of the diffuser lens 340 are included in the same plane.

[0115] Microscopic irregularities are formed on the surface of the diffuser lens 340. The diffuser lens 340 refracts the incident light at a desired diffusion angle (light distribution angle) and diffuses and shapes the light by utilizing the diffusion function of the microscopic irregularities. The diffuser lens 340 diffuses light more strongly in a certain direction than in other directions. Specifically, the diffuser lens 340 diffuses light more strongly in the length direction (longitudinal direction) than in the width direction (shortitudinal direction).

[0116] The diffuser lens 340 is designed and manufactured (created) so that the diffuser lens 340 as a whole has the performance of diffusing the incident light at a predetermined angle by statistical evaluation. For example, the relationship between the light intensity and the diffusion angle may be approximated by a predetermined distribution function (e.g., Gaussian distribution, etc.), and the angle at which the intensity of the diffused light is a predetermined intensity (e.g., half) of the intensity of the incident light may be set as the diffusion angle. Therefore, the diffuser lens 340 is not created by specifying the size or shape of each of the projections and recesses formed on the surface. In other words, the diffuser lens 340 is intended to exhibit performance as the diffuser lens 340 as a whole by statistical evaluation.

[0117] Light emitted from LED 322 is incident on and focused by focusing lens 330. The light focused by focusing lens 330 is incident on diffuser lens 340. The lengthwise (longitudinal) component of the light is diffused according to the shape and size of the irregularities formed on the surface of diffuser lens 340, and is emitted from diffuser lens 340.

[0118] Thus, the width-direction (short-side direction) component becomes the light condensed by the condenser lens 330, and the length-direction (long-side direction) component becomes the light diffused by the diffuser lens 340, and is emitted from the opening 312 of the lighting device 300.

[0119] The diffuser lens 340 may be one that can refract and diffusely shape the incident light at a desired diffusion angle (light distribution angle) even if it does not have minute irregularities on its surface.

[0120] <<<Configuration of the LED substrate 320>>> FIG. 4(a) is a front view showing the configuration of one LED substrate 320. FIG. 4(b) is a conceptual diagram showing the connection between the LED 322 and the power supply unit 100 on one LED substrate 320. As shown in FIG. 4(a), on the LED substrate 320, 72 LEDs 322-1 to 322-72 are linearly arranged in a row along the longitudinal direction of the LED substrate 320.

[0121] The plurality of LEDs 322 mounted on the LED substrate 320 are grouped and controlled by the power supply adjustment substrate 220. For example, the 72 LEDs 322-1 to 322-72 can be divided into two groups, a first group and a second group, and are controlled by the power supply adjustment substrate 220. Hereinafter, the group is referred to as a channel (CN).

[0122] The 72 LEDs 322-1 to 322-72 can be grouped into 36 LEDs 322-1 to 322-36 belonging to the first channel and 36 LEDs 322-37 to 322-72 belonging to the second channel. For simplicity, the 36 LEDs 322 (LEDs 322-1 to 322-36) belonging to the first channel are referred to as the first CH LEDs 322, and the 36 LEDs 322 (LEDs 322-37 to 322-72) belonging to the second channel are referred to as the second CH LEDs 322.

[0123] Furthermore, the first channel LED 322 and the second channel LED 322 are controlled separately for three board regions. Specifically, as shown in Fig. 4(a), the first channel LED 322 is controlled separately for three board regions 1-1, 1-2, and 1-3. The second channel LED 322 is controlled separately for three board regions 2-1, 2-2, and 2-3.

[0124] For simplicity, the following will describe the first channel LED 322. As shown in Fig. 4(b), the first channel LED 322 belonging to each of the board regions 1-1, 1-2, and 1-3 is composed of 12 LEDs 322 electrically connected in series. The 12 LEDs 322 belonging to each of the board regions 1-1, 1-2, and 1-3 are supplied with a power supply voltage from the power supply unit 100 separately from each other. That is, the three board regions 1-1, 1-2, and 1-3 are connected to the power supply unit 100 in parallel with each other, and a power supply voltage is supplied to each of the 12 LEDs 322.

[0125] In this way, by supplying the power supply voltage to each of the 12 LEDs 322, it is possible to lower the maximum value of the power supply voltage supplied to each of the 12 LEDs 322. In other words, by supplying the power supply voltage divided for each of the 12 LEDs 322 connected in series, it is possible to make the power supply voltage smaller than the power supply voltage supplied to all of the 36 LEDs 322 connected in series. It is possible to select from various power supply units 100 that satisfy the specifications, and the range of power supply unit 100 choices can be expanded.

[0126] Furthermore, the 12 LEDs 322 belonging to the substrate area 1-1 are supplied with a constant current generated by the buffer circuit 224-1-1 and the constant current circuit 226-1-1. The 12 LEDs 322 belonging to the substrate area 1-2 are supplied with a constant current generated by the buffer circuit 224-1-2 and the constant current circuit 226-1-2. The 12 LEDs 322 belonging to the substrate area 1-3 are supplied with a constant current generated by the buffer circuit 224-1-3 and the constant current circuit 226-1-3. In this way, for each 12 LEDs 322 connected in series, the current to be supplied is generated separately and supplied. Note that the configurations and functions of the buffer circuit 224 and the constant current circuit 226 will be described later.

[0127] By configuring in this way, when controlling the current so as to achieve the same brightness, the current value supplied to the 12 LEDs 322 connected in series can be made smaller than the current value supplied to the 36 LEDs 322 connected in series.

[0128] The second CH LEDs 322 are similarly configured and similarly controlled. Also, all the LEDs 322 of the LED substrates 320-1 to 320-k are similarly configured and similarly controlled. In this way, without applying a high voltage to the plurality of LEDs 322 connected in series, the current value to be supplied can be lowered, and the LEDs 322 can be made to emit light while maintaining the brightness.

[0129] <<<Correspondence relationship between the power supply unit 100, the power supply adjustment substrate 220, the LED substrate 320, and the channels of the LED substrate 320>>> FIG. 5 is a table showing an example of the correspondence relationship between the power supply unit 100, the power supply adjustment substrate 220, the LED substrate 320, and the channels of the LED substrate 320.

[0130] <<Number of LED substrates 320>> As described above, a plurality of, for example, 72 LEDs 322 are mounted on one LED substrate 320. The number of LED substrates 320 is determined by the length or the like according to the size (length or the like) of the object to be illuminated. Once the number of LED substrates 320 is determined, the number of LEDs 322 is also determined. The number of power adjustment substrates 220 is determined according to the number of LED substrates 320.

[0131] <<Type of LED 322 and Number of Power Units 100>> Also, the type of LED 322 is determined according to the lighting conditions of the object to be illuminated and the like. Therefore, the number of power units 100 is determined according to the current value required by the LEDs 322, the number of LEDs 322, and the like.

[0132] In the lighting system 10 according to the present embodiment, the power control substrate 210 detects the number of mounted power adjustment substrates 220 and the number of LED substrates 320 at startup and stores them in the RAM.

[0133] Specifically, the FPGA mounted on the power control substrate 210 has a register (not shown) for 10 bits. The register for 10 bits corresponds to the power adjustment substrates 220-1 to 220-10 (FIG. 5). When the power adjustment substrate 220 is mounted, the value of the bit corresponding to the mounted power adjustment substrate 220 becomes "0". When the power adjustment substrate 220 is not mounted, the value of the corresponding bit becomes "1". The processor of the power control substrate 210 can obtain the presence or absence of the power adjustment substrate 220 and count the number of mounted power adjustment substrates 220 by reading the value of this register of the FPGA.

[0134] The power adjustment board 220 has a DIP switch (not shown). The on or off state of a predetermined 1-bit of the DIP switch indicates the number of LED boards 320 connected to the power adjustment board 220. The FPGA of the power control board 210 can obtain the number (total number) of LED boards 320 connected to the power adjustment board 220 by detecting the on or off state of a predetermined 1-bit of the DIP switch. Since the FPGA of the power control board 210 detects the on or off state of the DIP switch, it can be released for other processes without occupying the I / O, which is a hardware resource of the processor. Note that the processor of the power control board 210 may directly detect the on or off state of the DIP switch. The on or off state of the DIP switch can be accurately obtained.

[0135] In this way, the processor of the power control board 210 can obtain the number of power adjustment boards 220 and the number of LED boards 320 that are connected and operable. Hereinafter, the correspondence relationship of the example shown in FIG. 5 will be described.

[0136] <<LED board 320 number and channel number>> The lighting device 300 can mount up to 20 LED boards 320-1 to 320-20. FIG. 5 shows the correspondence relationship from the shortest state to the longest state of the lighting device 300, and also shows the LED boards 320 housed in the housing 310 from the shortest state to the longest state of the lighting device 300.

[0137] In FIG. 5, the numbers of the LED boards 320-1 to 320-20 are simply set to 1 to 20. Also, as described above, each of the LED boards 320-1 to 320-20 has two channels, namely the first channel and the second channel. In the correspondence relationship of FIG. 5, the overall channel numbers from the LED board 320-1 to the LED board 320-20 are shown in consecutive numbers from 1 to 40 for distinction.

[0138] <<Number of power adjustment boards 220>> In the lighting system 10 according to the present embodiment, one power supply adjustment board 220 can control a maximum of two LED boards 320. Therefore, one power supply adjustment board 220 corresponds to four channels and corresponds to 144 (=72×2=36×4 channels) LEDs 322. That is, one power supply adjustment board 220 controls current supplied to 144 (=72×2) LEDs 322. The lighting device 300 has a maximum of ten power supply adjustment boards 220-1 to 220-10. In the correspondence relationship in FIG. 5, the numbers of the power supply adjustment boards 220-1 to 220-10 are simply 1 to 10.

[0139] <<Number of power supply units 100>> In the lighting system 10 according to this embodiment, one power supply unit 100 supplies power to the LEDs 322 of a maximum of six channels (216 LEDs=6×36 LEDs 322). That is, one power supply unit 100 corresponds to three LED boards 320, and supplies power to the LEDs 322 mounted on the three LED boards 320. The lighting system 10 has six power supply units 100-1 to 100-6 at the maximum. In the correspondence relationship in FIG. 5, the power supply units 100-1 to 100-6 are simply numbered 1 to 6.

[0140] <<Correspondence relationship from shortest state to longest state of the lighting device 300>> The lighting system 10 according to this embodiment can select the number of power supply units 100 and power supply adjustment boards 220 according to the number of LED boards 320 mounted on the lighting device 300. The power supply control board 210 controls the current supplied to the LEDs 322 according to the number of power supply adjustment boards 220 and the number of LED boards 320 connected. The following describes the configurations of the power supply units 100 and power supply adjustment boards 220 corresponding to the number of LED boards 320 (from minimum to maximum).

[0141] <When one LED board 320-1 is mounted (shortest position)> When one LED board 320-1 is mounted, it is sufficient to supply current to the LEDs 322 of channels 1 and 2. In this case, the lighting system 10 requires one power supply unit 100-1 and one power supply adjustment board 220-1.

[0142] The power supply unit 100-1 is connected to one LED board 320-1 and supplies power to 72 LEDs 322 of channels 1 and 2 mounted on the LED board 320-1. The power supply adjustment board 220-1 is connected to one LED board 320-1 and controls the current supplied to the 72 LEDs 322 of channels 1 and 2 mounted on the LED board 320-1.

[0143] <When two LED boards 320-1 to 320-2 are installed> When two LED boards 320-1 to 320-2 are mounted, current may be supplied to the LEDs 322 of channels 1 to 4. In this case, the lighting system 10 requires one power supply unit 100-1 and one power supply adjustment board 220-1.

[0144] The power supply unit 100-1 is connected to two LED boards 320-1 and 320-2. 72 LEDs 322 for channels 1 and 2 mounted on an LED board 320-1; Power is supplied to 72 LEDs 322 in channels 3 and 4 mounted on the LED board 320-2.

[0145] The power supply adjustment board 220-1 is connected to two LED boards 320-1 and 320-2. 72 LEDs 322 for channels 1 and 2 mounted on an LED board 320-1; It controls the current supplied to the 72 LEDs 322 of channels 3 and 4 mounted on the LED board 320-2.

[0146] <When three LED boards 320-1 to 320-3 are installed> When three LED boards 320-1 to 320-3 are mounted, current may be supplied to the LEDs 322 of channels 1 to 6. In this case, the lighting system 10 requires one power supply unit 100-1 and two power supply adjustment boards 220-1 and 220-2.

[0147] The power supply unit 100-1 is connected to three LED boards 320-1 to 320-3. 72 LEDs 322 for channels 1 and 2 mounted on an LED board 320-1; 72 LEDs 322 for channels 3 and 4 mounted on an LED board 320-2; Power is supplied to 72 LEDs 322 in channels 5 and 6 mounted on the LED board 320-3.

[0148] The power supply adjustment board 220-1 is connected to two LED boards 320-1 and 320-2. 72 LEDs 322 for channels 1 and 2 mounted on an LED board 320-1; It controls the current supplied to the 72 LEDs 322 of channels 3 and 4 mounted on the LED board 320-2.

[0149] Furthermore, the power supply adjustment board 220-2 is connected to one LED board 320-3. The power supply adjustment board 220-2 controls the current supplied to the 72 LEDs 322 of channels 5 and 6 mounted on the LED board 320-3.

[0150] <When four LED boards 320-1 to 320-4 are installed> When four LED boards 320-1 to 320-4 are mounted, current may be supplied to the LEDs 322 of channels 1 to 8. In this case, the lighting system 10 requires two power supply units 100-1 to 100-2 and two power supply adjustment boards 220-1 and 220-2.

[0151] The power supply unit 100-1 is connected to three LED boards 320-1 to 320-3. 72 LEDs 322 for channels 1 and 2 mounted on an LED board 320-1; 72 LEDs 322 for channels 3 and 4 mounted on an LED board 320-2; Power is supplied to 72 LEDs 322 in channels 5 and 6 mounted on the LED board 320-3.

[0152] Furthermore, the power supply unit 100-2 is connected to one LED board 320-4. The power supply unit 100-2 supplies power to the 72 LEDs 322 in channels 7 and 8 mounted on the LED board 320-4.

[0153] The power supply adjustment board 220-1 is connected to two LED boards 320-1 and 320-2. 72 LEDs 322 for channels 1 and 2 mounted on an LED board 320-1; It controls the current supplied to the 72 LEDs 322 of channels 3 and 4 mounted on the LED board 320-2.

[0154] Furthermore, the power supply adjustment board 220-2 is connected to two LED boards 320-3 and 320-4. 72 LEDs 322 for channels 5 and 6 mounted on an LED board 320-3; It controls the current supplied to the 72 LEDs 322 in channels 7 and 8 mounted on the LED board 320-4.

[0155] <When five LED boards 320-1 to 320-5 are installed> When five LED boards 320-1 to 320-5 are mounted, current may be supplied to the LEDs 322 of channels 1 to 10. In this case, the lighting system 10 requires two power supply units 100-1 to 100-2 and three power supply adjustment boards 220-1 to 220-3.

[0156] The power supply unit 100-1 is connected to three LED boards 320-1 to 320-3. 72 LEDs 322 for channels 1 and 2 mounted on an LED board 320-1; 72 LEDs 322 for channels 3 and 4 mounted on an LED board 320-2; Power is supplied to 72 LEDs 322 in channels 5 and 6 mounted on the LED board 320-3.

[0157] Furthermore, the power supply unit 100-2 is connected to two LED boards 320-4 and 320-5. 72 LEDs 322 for channels 7 and 8 mounted on an LED board 320-4; Power is supplied to 72 LEDs 322 in channels 9 and 10 mounted on an LED board 320-5.

[0158] The power supply adjustment board 220-1 is connected to two LED boards 320-1 and 320-2. 72 LEDs 322 for channels 1 and 2 mounted on an LED board 320-1; It controls the current supplied to the 72 LEDs 322 of channels 3 and 4 mounted on the LED board 320-2.

[0159] Furthermore, the power supply adjustment board 220-2 is connected to two LED boards 320-3 and 320-4. 72 LEDs 322 for channels 5 and 6 mounted on an LED board 320-3; It controls the current supplied to the 72 LEDs 322 in channels 7 and 8 mounted on the LED board 320-4.

[0160] The power supply adjustment board 220-3 is connected to one LED board 320-5. The power supply adjustment board 220-3 controls the current supplied to the 72 LEDs 322 of channels 9 and 10 mounted on the LED board 320-5.

[0161] <When six LED boards 320-1 to 320-6 are installed> When six LED boards 320-1 to 320-6 are mounted, current may be supplied to the LEDs 322 of channels 1 to 12. In this case, the lighting system 10 requires two power supply units 100-1 to 100-2 and three power supply adjustment boards 220-1 to 220-3.

[0162] The power supply unit 100-1 is connected to three LED boards 320-1 to 320-3. 72 LEDs 322 for channels 1 and 2 mounted on an LED board 320-1; 72 LEDs 322 for channels 3 and 4 mounted on an LED board 320-2; Power is supplied to 72 LEDs 322 in channels 5 and 6 mounted on the LED board 320-3.

[0163] Furthermore, the power supply unit 100-2 is connected to the three LED boards 320-4 to 320-6. 72 LEDs 322 for channels 7 and 8 mounted on an LED board 320-4; 72 LEDs 322 in channels 9 and 10 mounted on an LED board 320-5; Power is supplied to 72 LEDs 322 in channels 11 and 12 mounted on an LED board 320-6.

[0164] The power supply adjustment board 220-1 is connected to two LED boards 320-1 and 320-2. 72 LEDs 322 for channels 1 and 2 mounted on an LED board 320-1; It controls the current supplied to the 72 LEDs 322 of channels 3 and 4 mounted on the LED board 320-2.

[0165] Furthermore, the power supply adjustment board 220-2 is connected to two LED boards 320-3 and 320-4. 72 LEDs 322 for channels 5 and 6 mounted on an LED board 320-3; It controls the current supplied to the 72 LEDs 322 in channels 7 and 8 mounted on the LED board 320-4.

[0166] The power supply adjustment board 220-3 is connected to two LED boards 320-5 and 320-6. 72 LEDs 322 in channels 9 and 10 mounted on an LED board 320-5; It controls the current supplied to the 72 LEDs 322 in channels 11 and 12 mounted on the LED board 320-6.

[0167] <When seven LED boards 320-1 to 320-7 are installed> When seven LED boards 320-1 to 320-7 are mounted, current may be supplied to the LEDs 322 of channels 1 to 14. In this case, the lighting system 10 requires three power supply units 100-1 to 100-3 and three power supply adjustment boards 220-1 to 220-4.

[0168] The configuration and processing of the two power supply units 100-1 and 100-2 and the three power supply adjustment boards 220-1 to 220-3 are similar to those of the above-mentioned <When six LED boards 320-1 to 320-6 are mounted>.

[0169] Furthermore, the power supply unit 100-3 and the power supply adjustment board 220-4 have the same configuration and processing as in the above-mentioned <When one LED board 320-1 is mounted (shortest state)>. "Power supply unit 100-1" should be read as "power supply unit 100-3" "Power supply adjustment board 220-1" should be read as "power supply adjustment board 220-4" "LED board 320-1" should be read as "LED board 320-7" Simply read "Channels 1 and 2" as "Channels 13 and 14."

[0170] <When eight LED boards 320-1 to 320-8 are installed> When eight LED boards 320-1 to 320-8 are mounted, current may be supplied to the LEDs 322 of channels 1 to 16. In this case, the lighting system 10 requires three power supply units 100-1 to 100-3 and four power supply adjustment boards 220-1 to 220-4.

[0171] In this case, the configuration and processing of the two power supply units 100-1 and 100-2 and the three power supply adjustment boards 220-1 to 220-3 are the same as those in the case where six LED boards 320-1 to 320-6 are mounted. Furthermore, the configuration and processing of the power supply unit 100-3 and the power supply adjustment board 220-4 are the same as those in the case where two LED boards 320-1 to 320-2 are mounted. "Power supply unit 100-1" should be read as "power supply unit 100-3" "Power supply adjustment board 220-1" should be read as "power supply adjustment board 220-4" "LED board 320-1" should be read as "LED board 320-7" "Channels 1 and 2" should be read as "Channels 13 and 14" "LED board 320-2" should be read as "LED board 320-8" Simply read "Channels 3 and 4" as "Channels 15 and 16."

[0172] <When nine LED boards 320-1 to 320-9 are installed> When nine LED boards 320-1 to 320-9 are mounted, current may be supplied to the LEDs 322 of channels 1 to 18. In this case, the lighting system 10 requires three power supply units 100-1 to 100-3 and five power supply adjustment boards 220-1 to 220-5.

[0173] In this case, the configuration and processing of the two power supply units 100-1 and 100-2 and the three power supply adjustment boards 220-1 to 220-3 are the same as those in the case where six LED boards 320-1 to 320-6 are mounted. Furthermore, the configuration and processing of the power supply unit 100-3 and the power supply adjustment boards 220-4 and 220-5 are the same as those in the case where three LED boards 320-1 to 320-3 are mounted. "Power supply unit 100-1" should be read as "power supply unit 100-3" "Power supply adjustment board 220-1" should be read as "power supply adjustment board 220-4" "Power supply adjustment board 220-2" should be read as "power supply adjustment board 220-5" "LED board 320-1" should be read as "LED board 320-7" "Channels 1 and 2" should be read as "Channels 13 and 14" "LED board 320-2" should be read as "LED board 320-8" Simply read "Channels 3 and 4" as "Channels 15 and 16." "LED board 320-3" should be read as "LED board 320-9" Simply read "Channels 5 and 6" as "Channels 17 and 18."

[0174] <When 10 LED boards 320-1 to 320-10 are installed> When ten LED boards 320-1 to 320-10 are mounted, current may be supplied to the LEDs 322 of channels 1 to 20. In this case, the lighting system 10 has four power supply units 100-1 to 100-4 and five power supply adjustment boards 220-1 to 220-5.

[0175] In this case, the configuration and processing of the two power supply units 100-1 and 100-2 and the three power supply adjustment boards 220-1 to 220-3 are the same as those in the case where six LED boards 320-1 to 320-6 are mounted. Furthermore, the configuration and processing of the power supply units 100-3 and 100-4 and the power supply adjustment boards 220-4 and 220-5 are the same as those in the case where four LED boards 320-1 to 320-4 are mounted. "Power supply unit 100-1" should be read as "power supply unit 100-3" "Power supply unit 100-2" should be read as "power supply unit 100-4" "Power supply adjustment board 220-1" should be read as "power supply adjustment board 220-4" "Power supply adjustment board 220-2" should be read as "power supply adjustment board 220-5" "LED board 320-1" should be read as "LED board 320-7" "Channels 1 and 2" should be read as "Channels 13 and 14" "LED board 320-2" should be read as "LED board 320-8" "Channels 3 and 4" should be read as "Channels 15 and 16" "LED board 320-3" should be read as "LED board 320-9" "Channels 5 and 6" should be read as "Channels 17 and 18" "LED board 320-4" should be read as "LED board 320-10" Simply read "Channels 7 and 8" as "Channels 19 and 20."

[0176] <When 11 LED boards 320-1 to 320-11 are installed> When eleven LED boards 320-1 to 320-11 are mounted, current may be supplied to the LEDs 322 of channels 1 to 22. In this case, the lighting system 10 requires four power supply units 100-1 to 100-4 and six power supply adjustment boards 220-1 to 220-6.

[0177] In this case, the two power supply units 100-1 and 100-2 and the three power supply adjustment boards 220-1 to 220-3 have the same configuration and processing as the above-mentioned <When six LED boards 320-1 to 320-6 are mounted>. Furthermore, the configuration and processing of the power supply units 100-3 and 100-4 and the power supply adjustment boards 220-4 to 220-6 are the same as the above-mentioned <When five LED boards 320-1 to 320-5 are mounted>. Note that, "Power supply unit 100-1" should be read as "power supply unit 100-3" "Power supply unit 100-2" should be read as "power supply unit 100-4" "Power supply adjustment board 220-1" should be read as "power supply adjustment board 220-4" "Power supply adjustment board 220-2" should be read as "power supply adjustment board 220-5" "Power supply adjustment board 220-3" should be read as "power supply adjustment board 220-6" "LED board 320-1" should be read as "LED board 320-7" "Channels 1 and 2" should be read as "Channels 13 and 14" "LED board 320-2" should be read as "LED board 320-8" "Channels 3 and 4" should be read as "Channels 15 and 16" "LED board 320-3" should be read as "LED board 320-9" "Channels 5 and 6" should be read as "Channels 17 and 18" "LED board 320-4" should be read as "LED board 320-10" "Channels 7 and 8" should be read as "Channels 19 and 20" "LED board 320-5" should be read as "LED board 320-11" Simply read "Channels 9 and 10" as "Channels 21 and 22."

[0178] <When 12 LED boards 320-1 to 320-12 are installed> When twelve LED boards 320-1 to 320-12 are mounted, current may be supplied to the LEDs 322 of channels 1 to 24. In this case, the lighting system 10 has four power supply units 100-1 to 100-4 and six power supply adjustment boards 220-1 to 220-6.

[0179] In this case, the configuration and processing of the two power supply units 100-1 and 100-2 and the three power supply adjustment boards 220-1 to 220-3 are the same as those in the case where the six LED boards 320-1 to 320-6 are mounted. Furthermore, the configuration and processing of the power supply units 100-3 and 100-4 and the power supply adjustment boards 220-4 to 220-6 are the same as those in the case where the six LED boards 320-1 to 320-6 are mounted. "Power supply unit 100-1" should be read as "power supply unit 100-3" "Power supply unit 100-2" should be read as "power supply unit 100-4" "Power supply adjustment board 220-1" should be read as "power supply adjustment board 220-4" "Power supply adjustment board 220-2" should be read as "power supply adjustment board 220-5" "Power supply adjustment board 220-3" should be read as "power supply adjustment board 220-6" "LED board 320-1" should be read as "LED board 320-7" "Channels 1 and 2" should be read as "Channels 13 and 14" "LED board 320-2" should be read as "LED board 320-8" "Channels 3 and 4" should be read as "Channels 15 and 16" "LED board 320-3" should be read as "LED board 320-9" "Channels 5 and 6" should be read as "Channels 17 and 18" "LED board 320-4" should be read as "LED board 320-10" "Channels 7 and 8" should be read as "Channels 19 and 20" "LED board 320-5" should be read as "LED board 320-11" "Channels 9 and 10" should be read as "Channels 21 and 22" "LED board 320-6" should be read as "LED board 320-12" Simply read "Channels 11 and 12" as "Channels 23 and 24."

[0180] <When 13 LED boards 320-1 to 320-13 are installed> When 13 LED boards 320-1 to 320-13 are mounted, current is supplied to the LEDs 322 of channels 1 to 26. In this case, the lighting system 10 requires five power supply units 100-1 to 100-5 and seven power supply adjustment boards 220-1 to 220-7. The configuration and processing in this case are similar to those in the above-mentioned case where seven LED boards 320-1 to 320-7 are mounted, and may be interpreted appropriately.

[0181] <When 14 LED boards 320-1 to 320-14 are installed> When 14 LED boards 320-1 to 320-14 are mounted, current is supplied to the LEDs 322 of channels 1 to 28. In this case, the lighting system 10 requires five power supply units 100-1 to 100-5 and seven power supply adjustment boards 220-1 to 220-7. The configuration and processing in this case are the same as those in the above-mentioned case where eight LED boards 320-1 to 320-8 are mounted, and may be interpreted accordingly.

[0182] <When 15 LED boards 320-1 to 320-15 are installed> When 15 LED boards 320-1 to 320-15 are mounted, current is supplied to the LEDs 322 of channels 1 to 30. In this case, the lighting system 10 requires five power supply units 100-1 to 100-5 and eight power supply adjustment boards 220-1 to 220-8. The configuration and processing in this case are the same as those in the above-mentioned case where 9 LED boards 320-1 to 320-9 are mounted, and may be interpreted appropriately.

[0183] <When 16 LED boards 320-1 to 320-16 are installed> When 16 LED boards 320-1 to 320-16 are mounted, current is supplied to the LEDs 322 of channels 1 to 32. In this case, the lighting system 10 has six power supply units 100-1 to 100-6 and eight power supply adjustment boards 220-1 to 220-8. The configuration and processing in this case are similar to those in the above-mentioned case where 10 LED boards 320-1 to 320-10 are mounted, and may be interpreted appropriately.

[0184] <When 17 LED boards 320-1 to 320-17 are installed> When 17 LED boards 320-1 to 320-17 are mounted, current is supplied to the LEDs 322 of channels 1 to 34. In this case, the lighting system 10 has six power supply units 100-1 to 100-6 and nine power supply adjustment boards 220-1 to 220-9. The configuration and processing in this case are similar to those in the above-mentioned case where 11 LED boards 320-1 to 320-11 are mounted, and may be interpreted appropriately.

[0185] <When 18 LED boards 320-1 to 320-18 are installed> When 18 LED boards 320-1 to 320-18 are mounted, current is supplied to the LEDs 322 of channels 1 to 36. In this case, the lighting system 10 has six power supply units 100-1 to 100-6 and nine power supply adjustment boards 220-1 to 220-9. The configuration and processing in this case are similar to those in the case where 12 LED boards 320-1 to 320-12 are mounted, and may be interpreted appropriately.

[0186] <When 19 LED boards 320-1 to 320-19 are installed> When 19 LED boards 320-1 to 320-19 are mounted, it is necessary to supply current to the LEDs 322 of channels 1 to 38. In this case, the lighting system 10 has six power supply units 100-1 to 100-6 and ten power supply adjustment boards 220-1 to 220-10. In this case, the configuration and processing of the six power supply units 100-1 to 100-6 and the nine power supply adjustment boards 220-1 to 220-9 are the same as those in the case where 18 LED boards 320-1 to 320-18 are mounted.

[0187] Even if the configuration has 19 or more LED boards 320, a new power supply unit 100 is not added. The LEDs 322 of the 19th LED board 320-19 are connected to the three power supply units 100-1 to 100-3 already mounted, and the power supply voltage is supplied from each of the three power supply units 100-1 to 100-3 to the LEDs 322 of the LED board 320-19. The power supply voltages of the three power supply units 100-1 to 100-3 are supplied to the LEDs 322 of the LED boards 320-1 to 320-9, and the power supply voltages distributed from each of the three power supply units 100-1 to 100-3 are also supplied to the LEDs 322 of the LED board 320-19. With this configuration, it is not necessary to add and connect a new power supply unit 100.

[0188] <When 20 LED boards 320-1 to 320-20 are installed (maximum length)> When 20 LED boards 320-1 to 320-20 are mounted, it is necessary to supply current to the LEDs 322 of channels 1 to 40. In this case, the lighting system 10 has six power supply units 100-1 to 100-6 and ten power supply adjustment boards 220-1 to 220-10. In this case, the configuration and processing of the six power supply units 100-1 to 100-6 and the nine power supply adjustment boards 220-1 to 220-9 are the same as those in the case where 18 LED boards 320-1 to 320-18 are mounted.

[0189] Even if the configuration has 20 or more LED boards 320, a new power supply unit 100 is not added. The LEDs 322 of the 20th LED board 320-20 are connected to the three power supply units 100-4 to 100-6 already mounted, and the power supply voltage is supplied from each of the three power supply units 100-4 to 100-6 to the LEDs 322 of the LED board 320-20. The power supply voltages of the three power supply units 100-4 to 100-6 are supplied to the LEDs 322 of the LED boards 320-10 to 320-18, and the power supply voltages distributed from each of the three power supply units 100-4 to 100-6 are also supplied to the LEDs 322 of the LED board 320-20. With this configuration, it is not necessary to add and connect a new power supply unit 100.

[0190] In this way, the lighting system 10 according to the present embodiment can be equipped with up to 20 LED boards 320. That is, light can be emitted from the LEDs 322 in channels 1 to 40 (maximum).

[0191] As described above, even when the 19th LED board 320-19 or the 20th LED board 320-20 is mounted, there is no need to mount a new power supply unit 100. The power supply units 100-1 to 100-6 already have a margin in the power supply voltage. Therefore, each of the three power supply units 100-1 to 100-3 already mounted supplies the margin of power supply voltage to the LEDs 322 of the LED board 320-19. Similarly, each of the three power supply units 100-4 to 100-6 already mounted supplies the margin of power supply voltage to the LEDs 322 of the LED board 320-20.

[0192] In this way, the power supply voltage is supplied from the three power supply units 100-1 to 100-3 or the three power supply units 100-4 to 100-6 to the LEDs 322 of the LED boards 320-19 and 320-20. That is, by configuring the power supply voltage to be distributed and supplied from each of the multiple power supply units 100, the burden on each power supply unit 100 can be reduced, the power supply voltage can be stably distributed, and the surplus of the power supply voltage can be reduced. The power supply voltage can be stably supplied to both of the increased LED boards 320-19 and 320-20 without installing a new power supply unit 100.

[0193] The number of power supply units connected to each additional LED board 320 is not limited to three, but may be at least two or more. The number of additional LED boards 320 is not limited to two, but may be at least one or more. The number of LED boards 320 may be determined appropriately depending on the size and shape of the object to be illuminated.

[0194] <Power supply form> As described above, for the LED boards 320-1 to 320-18, one power supply unit 100 supplies power to the LEDs 322 of the multiple LED boards 320, whereas for the LED boards 320-19 and 320-20, multiple power supply units 100 supply power to the LEDs 322 of the single LED board 320. In this way, the lighting system 10 according to this embodiment: A first supply form in which one power supply unit 100 supplies power to the LEDs 322 of the multiple LED boards 320; A second supply form in which a plurality of power supply units 100 supply power to the LEDs 322 of one LED board 320; The present invention provides a supply voltage with a margin, and can effectively utilize the margin.

[0195] <<Power supply voltage detection>> As described above, the lighting system 10 according to this embodiment has a plurality of power supply units 100, and each of the power supply units 100 supplies a power supply voltage to each of the plurality of LED boards 320. The processor of the power supply control board 210 detects the power supply voltage supplied by each of the power supply units 100 and determines whether an appropriate power supply voltage is being supplied to each of the LED boards 320. As described above, the power supply control board 210 has an ADC, and detects a power supply voltage from the ADC that is the same as the voltage supplied to the LED boards 320.

[0196] FIG. 5 shows an example having 20 LED boards 320-1 to 320-20. It is not necessary to detect the power supply voltage in all of these LED boards 320-1 to 320-20. For example, the power supply voltage from the same power supply unit 100-1 is supplied to the LED boards 320-1 to 320-3. Therefore, it is sufficient to detect the power supply voltage supplied to any of the LED boards 320-1 to 320-20. In this embodiment, the power supply voltage supplied to the odd-numbered LED boards 320-1 to 320-20, that is, the LED boards 320-1, 320-3, . . . , 320-19 is detected. The power supply voltage may be detected for even-numbered boards or every third board. It is sufficient to detect and judge the power supply voltage.

[0197] Note that the power supply voltage actually supplied may change due to voltage drop over the length of the harness, the state of the electrical connections, deterioration over time, etc. Therefore, the power supply voltage supplied to all of the LED boards 320-1 to 320-20 may be detected.

[0198] <<Configuration of power supply adjustment board 220>> Fig. 6 is a functional block diagram showing the configuration of power supply adjustment board 220. Fig. 7 is a functional block diagram showing specific configurations of ladder resistor section 222, buffer circuit 224, and constant current circuit 226. Power supply adjustment boards 220-1 to 220-10 all have the same configuration and function. Figs. 6 and 7 show the configuration of power supply adjustment board 220-1 as a representative.

[0199] The power supply control board 210 converts the dimming value determined by the operation unit or an external control device into a resistance instruction value, and supplies it to the power supply adjustment board 220-1.

[0200] As described above, the power supply adjustment board 220-1 mainly A ladder resistor section 222-1, A buffer circuit 224-1; A constant current circuit 226-1; has.

[0201] <Ladder resistor section 222-1> In this embodiment, instead of a D / A converter semiconductor element, a ladder resistor circuit (see FIG. 7) in which a plurality of resistors are connected in a ladder shape is used to convert a digital signal into an analog signal.

[0202] The ladder resistor unit 222-1 has a ladder resistor unit 222-1-1, a ladder resistor unit 222-1-2, a ladder resistor unit 222-1-3, a ladder resistor unit 222-1-4, etc. Each of the ladder resistor unit 222-1-1, the ladder resistor unit 222-1-2, the ladder resistor unit 222-1-3, the ladder resistor unit 222-1-4, etc. has a ladder resistor circuit.

[0203] 6, ladder resistor unit 222-1-1 corresponds to the first channel of LED board 320-1, and ladder resistor unit 222-1-2 corresponds to the second channel of LED board 320-1. Similarly, ladder resistor unit 222-1-3 corresponds to the first channel of LED board 320-2, and ladder resistor unit 222-1-4 corresponds to the second channel of LED board 320-2.

[0204] <Buffer circuit 224-1> The buffer circuit 224-1 includes a buffer circuit 224-1-1, a buffer circuit 224-1-2, and a buffer circuit 224-1-3. The buffer circuit 224-1-1 corresponds to the LEDs 322-1 to 322-12 in the board region 1-1 (FIG. 4) described above. The buffer circuit 224-1-2 corresponds to the LEDs 322-13 to 322-24 in the board region 1-2. The buffer circuit 224-1-3 corresponds to the LEDs 322-25 to 322-36 in the board region 1-3. The buffer circuits 224-1-1 to 224-1-3 are circuits for electrically isolating the circuits in front and behind, and are circuits for preventing the influence of the constant current circuit 226-1 in the rear stage from affecting the ladder resistor unit 222-1 in the front stage.

[0205] <Constant current circuit 226-1> The constant current circuit 226-1 includes a constant current circuit 226-1-1, a constant current circuit 226-1-2, and a constant current circuit 226-1-3. The constant current circuit 226-1-1 corresponds to the LEDs 322-1 to 322-12 in the substrate region 1-1 (FIG. 4) described above. The constant current circuit 226-1-2 corresponds to the LEDs 322-13 to 322-24 in the substrate region 1-2. The constant current circuit 226-1-3 corresponds to the LEDs 322-25 to 322-36 in the substrate region 1-3.

[0206] As shown in FIG. 6, the power supply control board 210 is connected to the ladder resistor section 222-1 (ladder resistor section 222-1-1, ladder resistor section 222-1-2, ladder resistor section 222-1-3, ladder resistor section 222-1-4, etc.).

[0207] The ladder resistor section 222-1-1 is connected to the buffer circuit 224-1-1, the buffer circuit 224-1-2, and the buffer circuit 224-1-3. The ladder resistor section 222-1-2 is connected to the buffer circuit 224-2-1, the buffer circuit 224-2-2, and the buffer circuit 224-2-3.

[0208] The buffer circuit 224-1-1 is connected to the constant current circuit 226-1-1, the buffer circuit 224-1-2 is connected to the constant current circuit 226-1-2, and the buffer circuit 224-1-3 is connected to the constant current circuit 226-1-3. The buffer circuit 224-2-1 is connected to the constant current circuit 226-2-1, the buffer circuit 224-2-2 is connected to the constant current circuit 226-2-2, and the buffer circuit 224-2-3 is connected to the constant current circuit 226-2-3.

[0209] <<Generating dimming voltage signal from resistance indication>> As shown in FIG. 7, the ladder resistor unit 222-1-1 has a plurality of resistors connected in series, and a voltage of a predetermined voltage value is applied to the entire unit. For example, the ladder resistor unit 222-1-1 has 12 resistors connected in series. The ladder resistor unit 222-1-1 has 12 nodes 230-1 to 230-12 to which adjacent resistors are connected. The power supply control board 210 outputs a 12-bit digital signal (hereinafter referred to as a resistance instruction value) to the nodes 230-1 to 230-12. The resistance instruction value determines the potential at each of the 12 nodes 230-1 to 230-12, and controls the direction of the current flowing through the resistors. The combined resistance value of the ladder resistor unit 222-1-1 is switched depending on the direction of the current. A dimming voltage signal having a voltage value according to the combined resistance value of the ladder resistor unit 222-1-1 is generated. In this way, the ladder resistor section 222-1-1 generates the dimming voltage signal, which is an analog signal, from the resistance indication value, which is a 12-bit digital signal.

[0210] The dimming voltage signal generated by the ladder resistor unit 222-1-1 is supplied in parallel to the buffer circuit 224-1-1, the buffer circuit 224-1-2, and the buffer circuit 224-1-3. The buffer circuit 224-1-1, the buffer circuit 224-1-2, and the buffer circuit 224-1-3 each have an operational amplifier. The operational amplifier converts impedance, allowing a stable current to be generated from the dimming voltage signal.

[0211] The dimming voltage signal impedance-converted by the buffer circuit 224-1-1 is supplied to the constant current circuit 226-1-1. The constant current circuit 226-1-1 generates a constant current according to the voltage value of the supplied dimming voltage signal. The constant current generated by the constant current circuit 226-1-1 is supplied to the LEDs 322-1 to 322-12 in the board area 1-1 of the first channel of the LED board 320-1, causing the LEDs 322-1 to 322-12 to emit light with a brightness according to the voltage value of the dimming voltage signal.

[0212] The dimming voltage signal impedance-converted by the buffer circuit 224-1-2 is supplied to the constant current circuit 226-1-2. The constant current circuit 226-1-2 generates a constant current according to the voltage value of the supplied dimming voltage signal. The constant current generated by the constant current circuit 226-1-2 is supplied to the LEDs 322-13 to 322-24 in the board area 1-2 of the first channel of the LED board 320-1, causing the LEDs 322-13 to 322-24 to emit light with a brightness according to the voltage value of the dimming voltage signal.

[0213] The dimming voltage signal impedance-converted by the buffer circuit 224-1-3 is supplied to the constant current circuit 226-1-3. The constant current circuit 226-1-3 generates a constant current according to the voltage value of the supplied dimming voltage signal. The constant current generated by the constant current circuit 226-1-3 is supplied to the LEDs 322-25 to 322-36 in the board area 1-3 of the first channel of the LED board 320-1, causing the LEDs 322-25 to 322-36 to emit light with a brightness according to the voltage value of the dimming voltage signal.

[0214] Similarly, the ladder resistor section 222-1-2 etc. generates a constant current from the dimming voltage signal and supplies it to the corresponding LED 322, causing it to emit light with a brightness according to the voltage value of the dimming voltage signal.

[0215] <<Current detection unit 228>> The constant current circuit 226-1-1 has a current detection unit 228. The current detection unit 228 detects the current generated by the constant current circuit 226-1-1 and outputs a detection signal indicating the current value (V11, V13 in FIG. 6, V11 in FIG. 7, etc.).

[0216] In this embodiment, the current detection unit 228 is not provided in all the constant current circuits 226, but is provided only in some of the constant current circuits 226. For example, the current detection unit 228 is provided only in the constant current circuit 226 corresponding to the board region 1-1 of the first channel of the LED board 320. In this way, the configuration can be simplified and processing such as detection processing and determination processing can be performed quickly.

[0217] As described above, the detection signal generated by the current detection unit 228 is supplied to the power supply control board 210. The detection signal supplied to the power supply control board 210 is converted into a digital signal by the ADC of the power supply control board 210. In this manner, the processor of the power supply control board 210 can determine whether the constant current is an appropriate value. The determination of the current value will be described later.

[0218] <<<Dropping Processing>>> FIG. 8 is a graph showing the relationship between the resistance indication value and the value of the current supplied to the LED 322. As shown in FIG.

[0219] As described above, the ladder resistor section 222, the buffer circuit 224, and the constant current circuit 226 generate a current to be supplied to the LED 322 in accordance with the resistance command value, which is a digital signal. As described above, the RAM of the power supply control board 210 stores a dimming value table. In the dimming value table, the dimming value and the resistance command value are associated with each other so that the resistance command value increases as the dimming value increases. For this reason, it is expected that the brightness of the light emitted from the LED 322 increases as the dimming value (resistance command value) increases. For example, as shown by the straight line (including the thick solid line portion and the thin dashed line portion) sloping upward to the right in FIG. 8, the current value of the current supplied to the LED 322 increases linearly overall as the resistance command value increases, and it is expected that the brightness of the light emitted from the LED 322 increases.

[0220] However, even if the dimming value (resistance command value) is gradually increased from the minimum dimming value to the maximum dimming value, a phenomenon may occur in which the brightness of the light emitted from the LED 322 becomes darker rather than brighter within a certain dimming value range (hereinafter referred to as a drop phenomenon). For example, as shown by the thick solid line in Fig. 8, even if the resistance command value is increased, the current value of the current supplied to the LED 322 may suddenly drop at the first starting resistance command value, the second starting resistance command value, etc. For this reason, when the resistance command value is the first starting resistance command value, the second starting resistance command value, etc., the light emitted from the LED 322 also suddenly becomes darker.

[0221] If the dip phenomenon occurs, it may cause a user to feel uncomfortable. In addition, the dip phenomenon may occur in multiple ranges between the minimum dimming value (resistance command value) and the maximum dimming value (resistance command value) (such as the first starting resistance command value and the second starting resistance command value in FIG. 8). Therefore, it is preferable to prevent the dip phenomenon from occurring in the entire dimming value range from the minimum dimming value to the maximum dimming value. In this embodiment, both the phenomenon in which the value of the current supplied to the LED 322 decreases and the phenomenon in which the brightness of the light emitted from the LED 322 decreases are referred to as the dip.

[0222] The dip phenomenon occurs when the value of the current supplied to the LED 322 decreases in a range of dimming values ​​from the minimum dimming value to the maximum dimming value, as shown in Fig. 8. The decrease in the current supplied to the LED 322 is likely to occur when there are many resistors whose current direction changes in response to a change in the resistance command value among the multiple resistors constituting the ladder resistor section 222. For example, when the resistance command value is changed from 000011111111 to 000100000000, the number of resistors whose current direction changes increases.

[0223] Therefore, by detecting the point where the current value supplied to the LED 322 drops in the range from the minimum dimming value to the maximum dimming value and rewriting the dimming value table, it is possible to prevent the drop phenomenon. Specific processing will be described below.

[0224] 9 is a flowchart showing the drop / recovery detection process. This process is executed by the processor of the power supply control board 210. The drop / recovery detection process is called and executed as the resistance indication value ranges from the minimum resistance indication value to the maximum resistance indication value. Each time the drop / recovery detection process is called, the resistance indication value is increased little by little, for example by 1, to determine whether a drop has occurred or whether recovery from the drop has occurred. The amount of increase in the resistance indication value may be fine enough to determine whether a drop or recovery has occurred. The amount of increase in the resistance indication value may be 2 or more.

[0225] The dip / recovery detection process is called and executed at a predetermined timing as required other than when the illumination target is being illuminated, such as when the illumination system 10 is started up or at a timing corresponding to a user operation.

[0226] First, the processor of the power supply control board 210 reads the dimming value table and determines a resistance instruction value from the dimming value (step S811).

[0227] Next, the processor of the power supply control board 210 outputs a signal indicating the resistance command value determined in step S811 to the ladder resistor section 222 (step S813). The signal indicating the resistance command value is output to the nodes 230-1 to 230-12 of the ladder resistor section 222.

[0228] The ladder resistor unit 222 converts the signal (digital signal) indicating the resistance command value into a dimming voltage signal (analog signal) indicating the resistance command value. The dimming voltage signal is supplied to the constant current circuit 226 via the buffer circuit 224. The constant current circuit 226 generates a current having a current value corresponding to the resistance command value based on the dimming voltage signal and supplies the current to the LED 322. The current detection unit 228 detects the current generated by the constant current circuit 226, generates a detection signal indicating a voltage value corresponding to the current value, and outputs the detection signal to the power supply control board 210.

[0229] The processor of the power supply control board 210 receives the detection signal emitted from the current detection unit 228, and acquires the voltage value indicated by the detection signal as the current voltage value (the voltage value acquired by the current execution of the dip / recovery detection process) (step S815).

[0230] The processor of the power supply control board 210 determines whether the judgment reference voltage value is greater than the current voltage value (step S817). When a dip occurs, the judgment reference voltage value is the current voltage value immediately before the dip occurs. When no dip occurs, the judgment reference voltage value is the current voltage value acquired in step S815 and updated in step S835 by execution of the previous dip / recovery detection process. In this way, when a dip occurs, the judgment reference voltage value is maintained without being updated, and is updated in step S835 when the voltage recovers from the dip.

[0231] When the processor of the power supply control board 210 determines that the reference voltage value is greater than the current voltage value (YES), that is, when it determines that a drop has occurred, it determines whether the value of the drop detection flag is 1 or not (step S819). The drop detection flag is a flag indicating that a drop has been detected and that the voltage has not yet recovered from the drop. In other words, the drop detection flag is a flag indicating that a drop is occurring. When a drop is occurring, the value of the drop detection flag is 1, and when a drop is not occurring, the value of the drop detection flag is 0.

[0232] When the processor of the power supply control board 210 determines that the value of the drop detection flag is not 1 (NO), that is, immediately after the drop has occurred, it sets the value of the drop detection flag to 1 (step S821).

[0233] The processor of the power supply control board 210 stores the resistance instruction value immediately before the drop occurs in the RAM as the starting resistance instruction value (step S823), and ends this subroutine. The starting resistance instruction value is used later when executing a process for calibrating the resistance instruction value of the dimming value table.

[0234] When the processor of the power supply control board 210 determines in the process of step S819 that the value of the drop detection flag is 1 (YES), that is, when a further drop occurs during a drop, it immediately ends this subroutine. Since a drop has already been detected, this subroutine ends without executing any process. Note that in this embodiment, even if a further drop occurs during a drop, it is not treated as the occurrence of a new drop.

[0235] When the processor of the power supply control board 210 determines in the processing of step S817 that the judgment reference voltage value is equal to or lower than the current voltage value (NO), that is, when a drop has not occurred or when a drop has occurred and then recovered, it determines whether or not the judgment reference voltage value is equal to or lower than the current voltage value (step S825).

[0236] When the processor of the power supply control board 210 determines in the judgment process of step S825 that the judgment reference voltage value is equal to or lower than the current voltage value (YES), that is, when a drop has not occurred or when a drop has occurred and then recovered, it determines whether the value of the drop detection flag is 1 or not (step S827).

[0237] When the processor of the power supply control board 210 determines that the value of the dip detection flag is 1 (YES), that is, when the voltage value has recovered from the dip, it stores the resistance command value immediately before the voltage value recovered as the end-point resistance command value (step S829). The end-point resistance command value is also used when executing a process to calibrate the resistance command value in the dimming value table later. A dip occurs in the range of resistance command values ​​between the above-mentioned starting point resistance command value and this end-point resistance command value, and the resistance command value in the dimming value table between the starting point resistance command value and the end-point resistance command value can be calibrated later.

[0238] The processor of the power supply control board 210 sets the value of the drop detection flag to 0 (step S831). That is, since the power supply has recovered from the drop, the value of the drop detection flag is set to 0 to indicate that the power supply is not currently dropping.

[0239] The processor of the power supply control board 210 updates the value of the drop counter (step S833). The drop counter stores the number of times that a drop occurs while the resistance instruction value reaches from the minimum resistance instruction value to the maximum resistance instruction value. For example, in the example of Fig. 8, when the maximum resistance instruction value is reached, the value of the drop counter becomes 2. The value of the drop counter is used when calibrating the resistance instruction value in the dimming value table.

[0240] When the processor of the power supply control board 210 executes step S833 (when the voltage has recovered from a voltage drop) or when it determines in the process of step S827 that the value of the voltage drop detection flag is not 1 (NO) (when no voltage drop has occurred and the voltage drop is normal), it updates the judgment reference voltage value to the current voltage value (step S835) and ends this subroutine. When no voltage drop has occurred, including immediately after recovery from a voltage drop, the current voltage value is set to the judgment reference voltage value, so that it is possible to determine whether or not a new voltage drop has occurred the next time the voltage drop / recovery detection process is called and executed. Note that when a voltage drop is occurring, the processes of steps S825 to S835 are not executed and the judgment reference voltage value is not updated.

[0241] When the processor of the power supply control board 210 determines in the process of step S825 that the reference voltage value is not equal to or lower than the current voltage value (NO), it immediately ends this subroutine.

[0242] Fig. 10 is a table showing an example of a dimming value table. Fig. 10(a) is a dimming value table when a drop occurs, and Fig. 10(b) is a dimming value table when the resistance indication value in the section where the drop occurs is calibrated to a constant value when the drop occurs.

[0243] The dimming value table is a table that defines the relationship between the dimming value and the resistance instruction value. As described above, the operator operates the operation unit to determine the dimming value, and the power supply control board 210 refers to the dimming value table, reads out the resistance instruction value corresponding to the dimming value, and transmits it to the power supply adjustment board 220. The ladder resistor unit 222 of the power supply adjustment board 220 generates a dimming voltage signal from the received resistance instruction value, and the current detection unit 228 receives the dimming voltage signal via the buffer circuit 224, generates a constant current having a value corresponding to the voltage value indicated by the dimming voltage signal, and supplies the constant current to the LED 322.

[0244] By executing the drop / recovery detection process shown in FIG. 9, all of the start point resistance instruction values ​​and end point resistance instruction values ​​are stored in the RAM of the power supply control board 210.

[0245] <First starting point resistance indication, first ending point resistance indication> FIG. 10 is a table showing an example of the dimming value table.

[0246] For example, Fig. 10(a) shows a dimming value table before change. In the dimming value table shown in Fig. 10(a), as shown by dashed line A1, resistance command value 404 corresponding to dimming value 13 is the starting resistance command value, and resistance command value 420 corresponding to dimming value 17 is the end-point resistance command value. In this case, power supply control board 210 calibrates by changing all resistance command values ​​from the starting resistance command value to the end-point resistance command value to starting resistance command value 404.

[0247] Fig. 10(b) shows the dimming value table after the change. In the dimming value table shown in Fig. 10(b), as shown by dashed line A2, all resistance command values ​​corresponding to dimming value 13 to dimming value 17 are set to starting resistance command value 404. By calibrating in this way, for example, in the graph of Fig. 8, the current value from the first starting resistance command value to the first end resistance command value becomes a dashed line extending horizontally. In this way, by making the brightness of LED 322 constant from the first starting resistance command value to the first end resistance command value, it is possible to prevent a drop in brightness and prevent the user from feeling uncomfortable.

[0248] <Second starting point resistance indication, second ending point resistance indication> 10(a), as indicated by dashed line B1, a resistance command value 4389 corresponding to a dimming value 1010 is a starting resistance command value, and a resistance command value 4406 corresponding to a dimming value 1015 is an end point resistance command value. In this case, the power supply control board 210 performs calibration by changing all resistance command values ​​from the starting point resistance command value to the end point resistance command value to the starting point resistance command value 4389.

[0249] In the dimming value table shown in Fig. 10(b), as shown by dashed line B2, all resistance command values ​​corresponding to dimming value 1010 to dimming value 1015 are the starting resistance command value 4389. By calibrating in this way, for example, in the graph of Fig. 8, the current value from the second starting resistance command value to the second end resistance command value also becomes a dashed line extending horizontally. In this way, by making the brightness of LED 322 constant from the second starting resistance command value to the second end resistance command value, it is possible to prevent a drop in brightness and prevent the user from feeling uncomfortable.

[0250] In the above example, the resistance indication value from the starting resistance indication value to the end resistance indication value is calibrated to a constant value, but it may be calibrated to gradually increase. For example, the resistance indication value may be calibrated to gradually increase in a range from a resistance indication value smaller than the starting resistance indication value to a resistance indication value larger than the end resistance indication value. The resistance indication value may be calibrated to gradually increase in a linear manner or a curved manner. It is sufficient to calibrate so as not to cause the user to feel uncomfortable.

[0251] <<Auto voltage processing>> The lighting system 10 has a plurality of power supply units 100. For this reason, it is desirable to reduce power consumption as much as possible. Reducing power consumption also reduces heat generation.

[0252] In general, even if the brightness of light emitted from the LEDs 322 is the same, the current value required for each LED 322 differs due to variations in the characteristics of the LEDs 322. Furthermore, because of voltage drops caused by the length of the harness and the like, the power supply voltage required for each of the multiple power supply units 100 differs. For this reason, it is preferable to optimize the power supply voltage output from each of the multiple power supply units 100, rather than making the power supply voltage values ​​output from the multiple power supply units 100 the same.

[0253] In the following example, for simplicity, the lighting system 10 has the configuration shown in Fig. 11. That is, the lighting device 300 has eight LED boards 320-1 to 320-8. That is, the channel numbers are 1 to 16. The lighting system 10 has four power supply adjustment boards 220-1 to 220-4. The lighting system 10 has three power supply units 100-1 to 100-3.

[0254] Furthermore, as described above, in this embodiment, the power supply voltage supplied to the odd-numbered LED boards 320 among the LED boards 320 is detected. In the example shown in Fig. 11, the power supply voltage is detected only for the four LED boards 320-1, 320-3, 320-5, and 320-7.

[0255] FIG. 12 is a flowchart showing the auto-voltage process.

[0256] First, the processor of the power supply control board 210 turns on the LEDs 322 of 1 to 8CH at maximum illuminance (step S1211). That is, all the LEDs 322 mounted on the LED boards 320-1 to 320-4 are turned on at maximum illuminance. The LED boards 320-1 to 320-2 correspond to the power supply adjustment board 220-1, and the LED boards 320-3 to 320-4 correspond to the power supply adjustment board 220-2. The LED boards 320-1 to 320-3 correspond to the power supply unit 100-1, and the LED board 320-4 corresponds to the power supply unit 100-2.

[0257] As described above, all the LEDs 322 mounted on the LED boards 320-1 to 320-4 are turned on at maximum illuminance. Therefore, the maximum power supply voltage is supplied from the power supply unit 100-1 and the power supply unit 100-2 to the LED boards 320-1 to 320-4. This makes it possible to determine the state in which the power consumption is the highest.

[0258] Next, the processor of the power supply control board 210 acquires the power supply voltage supplied from the power supply unit 100-1 to the LED board 320-1 with the power supply adjustment board 220-1 (step S1213). As described above, the power supply voltage supplied from the power supply unit 100-1 is also supplied to the LED board 320-3 and can also be acquired by the power supply adjustment board 220-2, but since it is the power supply voltage supplied from the same power supply unit 100-1, the power supply voltage supplied to the LED board 320-1 is acquired as a representative.

[0259] Next, the processor of the power supply control board 210 determines whether the power supply voltage acquired in step S1213 is within a predetermined range (step S1215).

[0260] Here, the predetermined range is determined by assuming a voltage drop caused by the length of the harness, a margin for ensuring stability, and the like. As described above, in the longest state of the lighting device 300, 20 LED boards 320-1 to 320-20 are mounted. Among them, the LED board 320-19 is supplied with a power supply voltage with a margin from each of the power supply units 100-1 to 100-3. The LED board 320-20 is supplied with a power supply voltage with a margin from each of the power supply units 100-4 to 100-6. The predetermined range used in the determination process of step S1215 is determined by assuming a margin including the power supply voltage in the longest state of the lighting device 300. In the present embodiment, the value of the margin of the power supply voltage is set to a constant value, but may be changed according to the number of connected LED boards 320. The power supply voltage can be appropriately controlled without excess or deficiency. The predetermined range used in step S1215 is stored in an EEPROM. (Registered Trademark) The default value for the given range is 43.2 to 43.6 volts.

[0261] When the processor of the power supply control board 210 determines in the determination process of step S1215 that the power supply voltage is not within the predetermined range (NO), it sets the power supply voltage for both power supply units 100-1 and 100-2 (step S1217) and returns to the process of step S1213. By repeating the processes of steps S1213 to S1217, it is possible to optimally adjust the power supply voltage for both power supply units 100-1 and 100-2. The power supply voltage is set for the power supply unit 100. For example, as a setting method, a power supply voltage setting command is sent via RS232C.

[0262] In step S1217 described above, the voltage value of the power supply voltage is gradually changed to determine whether it is within the predetermined range. When it is determined that the voltage value of the power supply voltage is within the predetermined range, the process of step S1217 ends. The voltage value to which the voltage is gradually changed may be constant or variable. For example, the voltage value may be changed significantly at first, and then gradually decreased. The voltage value of the power supply voltage may also be changed so as to eventually approach the median value of the predetermined range.

[0263] In this way, the power supply voltages of both the power supply units 100-1 and 100-2 are set by only the power supply voltage supplied to the LED board 320-1. By performing the process in this way, the process can be completed easily and in a short time.

[0264] When the processor of the power supply control board 210 determines in the determination process of step S1215 that the power supply voltage is within the predetermined range (YES), it turns off the LEDs 322 of 1 to 8CH (the LEDs 322 of the four LED boards 320-1 to 320-4) (step S1219).

[0265] When the 1st to 8th CH LEDs 322, that is, only the four LED boards 320-1 to 320-4, are mounted on the lighting device 300, the process ends at step S1219.

[0266] Next, the processor of the power supply control board 210 lights up the LEDs 322 of CH7 to CH12 at maximum illuminance (step S1221). That is, all the LEDs 322 mounted on the LED boards 320-4 to 320-6 are turned on at maximum illuminance. The LED board 320-4 corresponds to the power supply adjustment board 220-2, and the LED boards 320-5 to 320-6 correspond to the power supply adjustment board 220-3. The LED boards 320-4 to 320-6 correspond to the power supply unit 100-2. By lighting them at maximum illuminance, it is possible to determine that the state is the highest in terms of power consumption.

[0267] Next, the processor of the power supply control board 210 acquires the power supply voltage supplied from the power supply unit 100-2 to the LED board 320-5 by the power supply adjustment board 220-3 (step S1223). As described above, the power supply voltage supplied from the power supply unit 100-2 is supplied to the LED board 320-5 and can be acquired by the power supply adjustment board 220-3.

[0268] Next, the processor of the power supply control board 210 judges whether the power supply voltage acquired in step S1223 is within a predetermined range (step S1225). This predetermined range may be determined in the same manner as the predetermined range in step S1215.

[0269] When the processor of power supply control board 210 determines in the determination process of step S1225 that the power supply voltage is not within the predetermined range (NO), it sets the power supply voltage of power supply unit 100-2 (step S1227) and returns the process to step S1223. By repeating the processes of steps S1223 to S1227, the power supply voltage of power supply unit 100-3 can be optimally adjusted.

[0270] The power supply voltages of both power supply units 100-1 and 100-2 are adjusted in the processing of steps S1211 to S1219 described above. Thereafter, the power supply voltage of power supply unit 100-2 is adjusted again by executing the processing of steps S1221 to S1229. That is, the power supply voltage of power supply unit 100-2 is roughly adjusted in the processing of steps S1211 to S1219, and is finely adjusted in the processing of steps S1221 to S1229. In this way, it is possible to simplify the configuration, facilitate the processing, and achieve more appropriate adjustment of the power supply voltage.

[0271] When the processor of the power supply control board 210 determines in the determination process of step S1225 that the power supply voltage is within a predetermined range (YES), it turns off the LEDs 322 of 7 to 12CH (the LEDs 322 of the two LED boards 320-5 to 320-6) (step S1229).

[0272] When the LEDs 322 for 1 to 12CH, that is, the six LED boards 320-1 to 320-6, are mounted on the lighting device 300, the process ends at step S1229.

[0273] Next, the processor of the power supply control board 210 turns on the LEDs 322 of CH13 to CH16 at maximum illuminance (step S1231). That is, all the LEDs 322 mounted on the LED boards 320-7 to 320-8 are turned on at maximum illuminance. The LED boards 320-7 to 320-8 correspond to the power supply adjustment board 220-4. The LED boards 320-7 to 320-8 correspond to the power supply unit 100-3. By turning on the LEDs at maximum illuminance, it can be determined that the state is the highest in power consumption.

[0274] Next, the processor of the power supply control board 210 acquires the power supply voltage supplied from the power supply unit 100-3 to the LED board 320-7 by the power supply adjustment board 220-4 (step S1233). As described above, the power supply voltage supplied from the power supply unit 100-3 is supplied to the LED board 320-7 and can be acquired by the power supply adjustment board 220-4.

[0275] Next, the processor of the power supply control board 210 judges whether the power supply voltage acquired in step S1233 is within a predetermined range (step S1235). This predetermined range may be determined in the same manner as the predetermined range in step S1215.

[0276] When the processor of power supply control board 210 determines in the determination process of step S1235 that the power supply voltage is not within the predetermined range (NO), it sets the power supply voltage of power supply unit 100-3 (step S1237) and returns the process to step S1233. By repeating the processes of steps S1233 to S1237, the power supply voltage of power supply unit 100-3 can be optimally adjusted.

[0277] If the processor of the power supply control board 210 determines in the judgment process of step S1235 that the power supply voltage is within a predetermined range (YES), it turns off the LEDs 322 of CH13 to CH16 (the LEDs 322 of the two LED boards 320-7 to 320-8) (step S1239) and terminates this subroutine.

[0278] <<<Power supply voltage monitoring with auto voltage processing>>> FIG. 13 is a table showing the power supply adjustment board 220 that monitors the power supply voltage in the auto voltage process from the shortest state to the longest state of the lighting device 300.

[0279] 11 and 12, the auto-voltage process when the lighting device 300 is in a state between the shortest state and the longest state has been described. Below, the power supply adjustment board 220 that monitors the power supply voltage of the lighting device 300 from the shortest state to the longest state will be described.

[0280] <When turning on LED322 for 1 to 4CH> When lighting the LEDs 322 of 1st to 4th channels (LED boards 320-1 to 320-2), they are controlled as follows: The power supply unit 100-1 supplies a power supply voltage to the LED boards 320-1 to 320-2. The power supply adjustment board 220-1 controls the power supply voltage supplied to the LED boards 320-1 to 320-2.

[0281] In this case, the power supply adjustment board 220-1 monitors the power supply voltage supplied from the power supply unit 100-1.

[0282] <When turning on LED322 for 1 to 6CH> When lighting the LEDs 322 of 1 to 6CH (LED boards 320-1 to 320-3), they are controlled as follows. The power supply unit 100-1 supplies power supply voltage to the LED boards 320-1 to 320-3. The power supply adjustment board 220-1 controls the power supply voltage supplied to the LED boards 320-1 to 320-2. The power supply adjustment board 220-2 controls the power supply voltage supplied to the LED board 320-3.

[0283] In this case, the power supply adjustment board 220-1 monitors the power supply voltage supplied from the power supply unit 100-1. As described above, the power supply voltage supplied from the power supply unit 100-1 is also supplied to the LED board 320-3 and can be acquired by the power supply adjustment board 220-2, but since it is the power supply voltage supplied from the same power supply unit 100-1, the power supply voltage supplied to the LED board 320-1 is acquired as a representative.

[0284] <When turning on LED322 for 1 to 8CH> When lighting the LEDs 322 of 1 to 8CH (LED boards 320-1 to 320-4), they are controlled as follows. Power supply unit 100-1 supplies power supply voltage to LED boards 320-1 to 320-3. Power supply unit 100-2 supplies power supply voltage to LED board 320-4. Power supply adjustment board 220-1 controls the power supply voltage supplied to LED boards 320-1 to 320-2. Power supply adjustment board 220-2 controls the power supply voltage supplied to LED boards 320-3 to 320-4.

[0285] In this case, the power supply adjustment board 220-1 monitors the power supply voltage supplied from the power supply unit 100-1. As described above, the power supply voltage supplied from the power supply unit 100-1 is also supplied to the LED board 320-3 and can be acquired by the power supply adjustment board 220-2, but since it is a power supply voltage supplied from the same power supply unit 100-1, the power supply voltage supplied to the LED board 320-1 is acquired as a representative. In addition, the power supply unit 100-2 supplies a power supply voltage to the LED board 320-4. However, in this embodiment, the power supply voltage supplied to the LED board 320-4 is not a target for monitoring. Therefore, only the power supply adjustment board 220-1 monitors the power supply voltage supplied from the power supply unit 100-1.

[0286] <When turning on LED322 for CH7 to CH12> When lighting the LEDs 322 of CH7 to CH12 (LED boards 320-4 to 320-6), they are controlled as follows. The power supply unit 100-2 supplies power supply voltage to the LED boards 320-4 to 320-6. The power supply adjustment board 220-2 controls the power supply voltage supplied to the LED board 320-4. The power supply adjustment board 220-3 controls the power supply voltage supplied to the LED boards 320-5 to 320-6.

[0287] In this case, the power supply adjustment board 220-5 monitors the power supply voltage supplied from the power supply unit 100-3. The power supply unit 100-3 supplies the power supply voltage to the LED boards 320-4 and 320-6. However, in this embodiment, the power supply voltage supplied to the LED boards 320-4 and 320-6 is not subject to monitoring. Therefore, only the power supply adjustment board 220-5 monitors the power supply voltage supplied from the power supply unit 100-3.

[0288] <When turning on LED322 for 13-16CH, 13-18CH, 13-20CH, 19-24CH, 25-28CH, 25-30CH, 25-32CH, and 30-36CH> These are monitored in the same manner as when the LEDs 322 for 1-4CH, 1-6CH, 1-8CH, and 7-12CH are lit up as described above. Specifically, 13-16CH and 25-28CH are monitored in the same manner as 1-4CH as described above. 13-18CH and 25-30CH are monitored in the same manner as 1-6CH as described above. 13-20CH and 25-32CH are monitored in the same manner as 1-8CH as described above. 19-24CH and 30-36CH are monitored in the same manner as 7-12CH as described above.

[0289] <When turning on LED322 for 1 to 40CH> When the LEDs 322 of 1 to 40CH are turned on, the maximum number of LED boards 320-1 to 320-20 is mounted.

[0290] As described above, the LEDs 322 of CH37 to CH38 are mounted on the LED board 320-19. The power supply voltages are distributed and supplied to the LEDs 322 of the LED board 320-19 from the power supply units 100-1 to 100-3.

[0291] The LEDs 322 of CH39 to CH40 are mounted on an LED board 320-20. Power supply voltages are distributed and supplied to the LEDs 322 of the LED board 320-20 from the power supply units 100-4 to 100-6.

[0292] 11 and 12, optimization of the power supply voltages of all of the power supply units 100-1 to 100-6 is completed by monitoring CH1 to CH4 to CH30 to CH36. Therefore, when the LED boards 320-19 and 320-20 are connected to the maximum length, the optimization process of the power supply voltages for the LED boards 320-19 and 320-20 is not executed, and the power supply voltage can be immediately supplied to the LED boards 320-19 and 320-20.

[0293] <<<Modification Example 1 (Circuit configuration 1 other than ladder resistor)>>> In the above example, the combined resistance value of the ladder resistors determines the current value of the current supplied to the LED 322. However, the present invention is not limited to this, and any other configuration may be used as long as the current value of the current supplied to the LED 322 can be determined by changing the total resistance value by switching the combination of multiple resistors.

[0294] <<<Modification Example 2 (Circuit configuration 2 other than ladder resistor)>>> In the above example, a configuration using a ladder resistor was shown. However, the present invention is not limited to this, and any configuration may be used as long as the control value is determined by dividing the current and controlling the direction of each divided current. For example, the present invention may be a circuit including a combination of impedance elements (capacitors and coils) and rectifying elements. Any configuration may be used as long as the control value is determined by dividing the current and controlling the direction of each divided current using various passive and active elements.

[0295] <<<Change Example 3 (Light Control Value Table)>>> In the above example, a configuration was shown in which a dimming value table was used to determine a control value from an adjustment value. However, the present invention is not limited to this, and an approximation formula such as a polynomial may be used to determine a control value from an adjustment value. By determining the coefficient value of the approximation formula and referring to the approximation formula, it is possible to determine one control value from one adjustment value. Any relationship may be used as long as it allows the adjustment value to be uniquely determined from the control value.

[0296] <<<Modification 4 (Number of LEDs 322 mounted on LED board 320)>>> In the above example, a configuration has been shown in which 72 (=2×36) LEDs 322 for two channels are always mounted on one LED board 320. However, the present invention is not limited to this, and one LED board 320 may be equipped with only 36 LEDs 322 for one channel, or with any number of LEDs 322 less than 72. Also, one LED board 320 may be equipped with LEDs 322 for three or more channels.

[0297] <<<Modification 5 (Correspondence between power supply adjustment board 220 and LED board 320)>>> 1 and 6, one power supply adjustment board 220 corresponds to two LED boards 320, but the present invention is not limited to this. One power supply adjustment board 220 may be configured to correspond to one or three or more LED boards 320. This may be determined appropriately depending on the wiring, wiring, arrangement, etc.

[0298] <<<Modification 6 (Correspondence between LED board 320 and channel (LED 322 belonging to))>>> 1, 4, and 6, a configuration in which LEDs 322 for two channels are mounted on one LED board 320 has been shown, but this is not limited thereto. One LED board 320 may be configured to mount LEDs 322 for one, three or more channels. This may be determined appropriately depending on the number, size, specifications, arrangement, and control method of the LEDs 322 mounted on one LED board 320.

[0299] <<<Change Example 7 (Correspondence between channels and LED322)>>> Although the configuration in which 36 LEDs 322 are assigned to one channel has been shown, this is not limiting. Another number of LEDs 322 may be assigned to one channel. This may be determined appropriately depending on the number, size, specifications, etc. of the LEDs 322.

[0300] <<<Modification Example 8 (Correspondence between channels and board areas)>>> As shown in Fig. 4, a configuration in which three board regions are associated with one channel is shown, but this is not limited thereto. One or three or more board regions may be associated with one channel. The number of board regions associated with one channel may be appropriately determined depending on the magnitude of the power supply voltage that can be applied to the LEDs 322 belonging to one board region, the number of LEDs 322 belonging to one board region, etc.

[0301] <<<Modification Example 9 (Relationship between ladder resistor section 222 and channel)>>> Although a configuration in which one ladder resistor unit 222 adjusts the brightness of the LEDs 322 belonging to one channel to be common has been shown, the present invention is not limited to this. A configuration in which one ladder resistor unit 222 adjusts the brightness of the LEDs 322 belonging to multiple channels to be common may also be used. With this configuration, the number of ladder resistor units 222 can be reduced, simplifying the circuit configuration. By reducing the number of ladder resistor units 222, heat generation by the ladder resistor units 222 can be suppressed.

[0302] <<<Modification 10 (Relationship between ladder resistor portion 222 and substrate area)>>> In the illustrated configuration, one ladder resistor unit 222 is shared by the LEDs 322 in three board regions included in one channel, and calibration for dips occurring in the one ladder resistor unit 222 is also shared for adjusting the brightness of the LEDs 322 in the three board regions. However, the present invention is not limited to this, and one ladder resistor unit 222 may be used only for the LEDs 322 in one board region, and calibration for dips occurring in the one ladder resistor unit 222 may also be used only for adjusting the brightness of the LEDs 322 in the one board region. Calibration can be reflected according to the characteristics of the LEDs 322 belonging to one board region.

[0303] <<<Modification Example 11 (Power supply voltage detection)>>> A configuration is shown in which the power supply voltage supplied to the odd-numbered LED boards 320-1 to 320-20 (LED boards 320-1, 320-3, ..., 320-19) is detected. However, this is not limiting, and the power supply voltages of all the LED boards 320-1 to 320-20 may be detected. In this way, the states of the connection lines and the contacts can be determined separately.

[0304] <<<Modification 12 (Configuration of power supply control board 210)>>> A configuration has been shown in which a single power supply control board 210 detects the power supply voltage (Vpp1 to Vppm) (see FIG. 1) supplied from the power supply unit 100 to the LED board 320 in an integrated manner, or detects the current generated by the constant current circuit 226 (V11, V13 in FIG. 6, V11 in FIG. 7, etc.). This is not limiting, and a configuration may be provided in which a plurality of power supply control boards 210 are provided to separately detect the power supply voltage supplied from the power supply unit 100 and the current generated by the constant current circuit 226. When a plurality of power supply control boards 210 are provided, they may be made to be able to communicate with each other, and one of the power supply control boards 210 may be controlled as the main power supply control board and the other power supply control boards 210 may be controlled as the sub power supply control board. In addition, all of the plurality of power supply control boards 210 may be configured to be able to communicate with each other on an equal basis. For example, even if a malfunction occurs in any of the power supply control boards 210, the remaining power supply control boards 210 can supplement and control each other.

[0305] <<<Modification Example 13 (Auto Voltage Processing)>>> In the above example, the power supply voltages of the two power supply units 100, 100-1 and 100-2, are roughly adjusted and set in the process of step S1217. However, the present invention is not limited to this, and the power supply voltages of three or more installed power supply units 100, for example, all of the power supply units 100, may be set in the process of step S1217. For example, in the configuration of the lighting system 10 shown in FIG. 11, the power supply voltages of the four power supply units 100, 100-1 to 100-4, may be set in the process of step S1217. In this way, the power supply voltages of the multiple power supply units 100 can be easily adjusted in a short time.

[0306] <<<<Scope of embodiment>>>> As described above, the present embodiment has been described. However, the description and drawings forming a part of this disclosure should not be understood as being limiting. Various embodiments not described here are included. [Explanation of symbols]

[0307] 10. Lighting System 100 Power Supply Units 200 Power supply control unit 210 Power supply control board 220 Power adjustment board 222 Ladder resistor section 226 Constant current circuit 300 Lighting Equipment 320 LED board 322 LED < / fpga> < / ram> < / rom>

Claims

1. A plurality of light source substrates, each of which is equipped with at least one light source body; a plurality of power supply units, each of which is associated with at least two of the plurality of light source boards, and which supplies a power supply voltage to a light source body mounted on the associated at least two light source boards; a voltage detection unit that detects a power supply voltage supplied to the light source body for a selected one of the at least two light source boards; A control unit that adjusts the power supply voltages of the power supply units corresponding to the at least two light source boards according to a detection result of the voltage detection unit.

2. The lighting system according to claim 1 , wherein the control unit adjusts a power supply voltage of one of the plurality of power supply units and a power supply voltage of at least one other power supply unit different from the one power supply unit, and then adjusts the power supply voltage of the other power supply unit.

3. In each of the plurality of light source boards, the mounted light source bodies are grouped in units of a predetermined number, and each of the plurality of light source boards has a plurality of light source body groups for each of the plurality of light source boards; In each of the plurality of light source substrates, the plurality of light source body groups are configured in parallel, The lighting system according to claim 1 , wherein a power supply voltage is supplied to the light source elements belonging to the light source element group.

4. The lighting system according to claim 3 , wherein each of the plurality of power supply units is connected in parallel to the plurality of light source body groups on the associated light source board, and supplies a power supply voltage to the light source elements belonging to each of the plurality of light source body groups.

5. The lighting system according to claim 3 , wherein at least two light source bodies belong to each of the plurality of light source body groups, and in each of the plurality of light source body groups, the at least two light source bodies are electrically connected in series.

6. The light source substrate may further include a housing having a first housing area capable of housing the plurality of light source substrates and a second housing area different from the first housing area; the second accommodation area is an accommodation area used when adding light source substrates in excess of a first maximum accommodation number that can be accommodated in the first accommodation area, 5. The lighting system of claim 4, wherein when a light source board is accommodated in the second accommodation area, one of the plurality of power supply units supplies a power supply voltage to a light source body mounted on the light source board accommodated in the first accommodation area and also supplies a power supply voltage to a light source body mounted on the one light source board.

7. The lighting system according to claim 6 , wherein in addition to the one power supply unit, a power supply voltage is supplied to the light source body mounted on the one light source board from another power supply unit different from the one power supply unit among the plurality of power supply units.

8. a plurality of power supply units each associated with at least two of the plurality of light source boards, each of which has at least one light source body mounted thereon, the plurality of power supply units supplying a power supply voltage to the light source bodies mounted on the at least two associated light source boards; a voltage detection unit that detects a power supply voltage supplied to the light source body for a selected one of the at least two light source boards; A control unit that adjusts the power supply voltage of the power supply units corresponding to the at least two light source boards in accordance with the detection result of the voltage detection unit.

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