JP7426584B2 - Light source devices, lighting devices, and lighting systems - Google Patents

Description

The present disclosure generally relates to a light source device, a lighting device, and a lighting system. More specifically, the present disclosure relates to a light source device, a lighting device, and a lighting system in which light is transmitted through a light guide member.

The lighting device (conventional lighting device) of Patent Document 1 is a lighting device using a semiconductor laser.

In a conventional illumination device, laser light emitted from a semiconductor laser is guided by a light guiding section to an imaging lens, and is focused by the imaging lens onto a wavelength conversion section. The laser light excites the wavelength converter and is scattered by the surface of the wavelength converter. Then, white light, which is a mixture of the yellow light emitted by the wavelength converter and the blue light scattered by the surface of the wavelength converter, is emitted to the outside of the lighting device by passing through the convex lens.

The above-mentioned light guide section extends from one end to the other end, and a semiconductor laser is disposed at one end of the light guide section, and a semiconductor laser is disposed at the other end of the light guide section. In this case, a wavelength conversion section and a photodetection section are arranged via an imaging lens.

The light detection unit receives white light, which is a mixture of the yellow light and blue laser light, including the yellow light emitted by the wavelength conversion unit, and generates electricity according to the amount of the received light. A detection signal, which is a signal, is output to the drive circuit. The drive circuit controls the laser beam based on the detection signal.

JP2017-213980A

In the conventional lighting device described above, the light emitting element (semiconductor laser) is arranged at the first end (one end) of the light guide member (light guide part), and the light emitting element (semiconductor laser) is arranged at the second end (the other end) of the light guide member. An optical sensor (light detection section) is arranged at the. That is, the light emitting element and the optical sensor are separated from each other with the light guide member in between, which causes the configuration to become complicated.

The present disclosure has been made in view of the above points, and an object of the present disclosure is to provide a light source device, a lighting device, and a lighting system that are equipped with an optical sensor and can have a simplified configuration. There is a particular thing.

A light source device according to an aspect of the present disclosure includes a light guide member that guides light between a first end and a second end, and a first light that enters the first end and exits from the second end. It is used together with a wavelength conversion member that converts the first light into second light having a different wavelength. The light source device includes a plurality of light emitting elements, an optical sensor, a driving device, and an abnormality detection section. The plurality of light emitting elements emit the first light incident on the first end by being supplied with a driving current. The optical sensor detects, of the second light, signal light that is incident on the second end and transmitted to the first end. The drive device supplies the drive current to the plurality of light emitting elements, and controls the drive current using a detection result of the signal light. The abnormality detection unit detects abnormalities in the wavelength conversion member, the light guide member, and the plurality of light emitting elements based on a rate of decrease in the amount of the signal light. The abnormality detection unit detects each abnormality of the wavelength conversion member, the light guide member, and the plurality of light emitting elements by comparing the rate of decrease with a first threshold value and a second threshold value. The first threshold value and the second threshold value are less than 100%, and the first threshold value is a value smaller than the second threshold value. The abnormality detection unit detects an abnormality in some of the plurality of light emitting elements if the rate of decrease is greater than or equal to the first threshold and less than or equal to the second threshold, and if the rate of decrease is greater than the second threshold. , detecting an abnormality in at least one of the wavelength conversion member and the light guide member.

An illumination lighting device according to one aspect of the present disclosure is used together with a light guide member, a wavelength conversion member, and a plurality of light emitting elements. The light guide member guides light between a first end and a second end. The wavelength conversion member converts the first light that enters the first end and exits from the second end into second light that has a different wavelength from the first light. The plurality of light emitting elements emit the first light by being supplied with a driving current. The lighting device includes an optical sensor, a drive device, and an abnormality detection section. The optical sensor detects the second light that is incident on the second end and transmitted to the first end as signal light. The drive device supplies the drive current to the light emitting element and controls the drive current using the detection result of the signal light. The abnormality detection unit detects abnormalities in the wavelength conversion member, the light guide member, and the plurality of light emitting elements based on a rate of decrease in the amount of the signal light. The abnormality detection unit detects each abnormality of the wavelength conversion member, the light guide member, and the plurality of light emitting elements by comparing the rate of decrease with a first threshold value and a second threshold value. The first threshold value and the second threshold value are less than 100%, and the first threshold value is a value smaller than the second threshold value. The abnormality detection unit detects an abnormality in some of the plurality of light emitting elements if the rate of decrease is greater than or equal to the first threshold and less than or equal to the second threshold, and if the rate of decrease is greater than the second threshold. , detecting an abnormality in at least one of the wavelength conversion member and the light guide member.

An illumination system according to one aspect of the present disclosure includes a light guide member, a wavelength conversion member, a plurality of light emitting elements, an optical sensor, a drive device, and an abnormality detection section. The light guide member guides light between a first end and a second end. The wavelength conversion member converts the first light that enters the first end and exits from the second end into second light that has a different wavelength from the first light. The plurality of light emitting elements emit the first light by being supplied with a driving current. The optical sensor detects, of the second light, signal light that is incident on the second end and transmitted to the first end. The drive device supplies the drive current to the light emitting element and controls the drive current using the detection result of the signal light. The abnormality detection unit detects abnormalities in the wavelength conversion member, the light guide member, and the plurality of light emitting elements based on a rate of decrease in the amount of the signal light. The abnormality detection unit detects each abnormality of the wavelength conversion member, the light guide member, and the plurality of light emitting elements by comparing the rate of decrease with a first threshold value and a second threshold value. The first threshold value and the second threshold value are less than 100%, and the first threshold value is a value smaller than the second threshold value. The abnormality detection unit detects an abnormality in some of the plurality of light emitting elements if the rate of decrease is greater than or equal to the first threshold and less than or equal to the second threshold, and if the rate of decrease is greater than the second threshold. , detecting an abnormality in at least one of the wavelength conversion member and the light guide member.

According to the light source device, illumination lighting device, and illumination system of the present disclosure, it is possible to include an optical sensor and to simplify the configuration.

FIG. 1 is a block diagram of a lighting system including a light source device according to an embodiment. FIG. 2 is an external view of the above lighting system. FIG. 3 is a block diagram of a light detection device of the above illumination system. FIG. 4A is a waveform diagram illustrating the operation of the above lighting system. FIG. 4B is another waveform diagram illustrating the operation of the above lighting system. FIG. 5 is a block diagram of a light source device according to a first modification. FIG. 6 is a circuit diagram of the abnormal element identifying section same as above.

Hereinafter, a light source device, a lighting device, and a lighting system according to embodiments will be described with reference to the drawings. Each figure described in the following embodiments and the like is a schematic diagram, and the ratio of the size and thickness of each component in the figure does not necessarily reflect the actual size ratio.

(Embodiment)
(1) Overall configuration of lighting system The overall configuration of the lighting system according to the embodiment will be described with reference to the drawings.

The lighting system 1 includes a light source device 2, a light guide member 3, and a lamp 4, as shown in FIG. The light source device 2 emits laser light L1 (first light). The laser beam L1 enters the first end 31 of the light guide member 3, passes through the inside of the light guide member 3, and exits from the second end 32 of the light guide member 3. The laser beam L1 emitted from the second end 32 is converted into wavelength-converted light (second light) by the wavelength conversion member 4a of the lamp 4, and most of the wavelength-converted light is irradiated from the lamp 4 into the illumination space as illumination light L2. be done. A part of the wavelength-converted light enters the second end 32 of the light guide member 3 as the signal light L3, and the signal light L3 passes through the inside of the light guide member 3 and exits from the first end 31 of the light guide member 3. Emits light.

The light source device 2 includes an illumination lighting device 5, a light source 6, and an optical member 7. The illumination lighting device 5 lights up the light source 6 by supplying a DC drive current I1 to the light source 6. The light source 6 emits a laser beam L1 when supplied with the drive current I1. Laser light L1 emitted from the light source 6 enters the first end 31 of the light guide member 3 via the optical member 7. As shown in FIG. 2, the light source device 2 includes a housing 2a. The housing 2a houses the lighting device 5, the light source 6, and the optical member 7. The light source device 2 is used together with a light guide member 3 and a lamp 4.

The lighting device 5 includes a drive device 5a and a photodetector 5b. The drive device 5a receives an AC voltage from the AC power source P1 and supplies a drive current I1 to the light source 6. The photodetector 5b detects the signal light L3 emitted from the first end 31 of the light guide member 3. The signal light L3 enters the second end 32 of the light guide member 3, passes through the interior of the light guide member 3, and exits from the first end 31 of the light guide member 3.

The lighting system 1 is used, for example, as an underwater lighting device that emits light from underwater, or as a headlight of a car.

(2) Light Source The light source 6 includes a plurality of light emitting elements 6a. Each of the plurality of light emitting elements 6a is a laser diode (laser element). The plurality of light emitting elements 6a supplied with the drive current I1 from the drive device 5a emit, for example, blue laser light L1. Although the electrical connection relationship of the plurality of light emitting elements 6a is a series connection, the connection relationship is not limited to this connection relationship. The electrical connection relationship between the plurality of light emitting elements 6a may be a parallel connection or a combination of series connection and parallel connection. Further, the light source 6 may include one light emitting element 6a. Note that each of the plurality of light emitting elements 6a included in the light source 6 is not limited to a laser diode, but may be another solid state light emitting element (semiconductor light emitting element) such as an LED (Light Emitting Diode) or an organic EL (Organic Electro Luminescence, OEL). There may be.

(3) Optical member As shown in FIG. 1, the optical member 7 includes a half mirror 7a. The half mirror 7a reflects the laser beam L1 emitted from the light source 6 toward the first end 31 of the light guide member 3. The optical member 7 then focuses the laser beam L1 and makes it enter the first end 31 of the light guide member 3. Note that the optical member 7 may include other optical components such as a mirror and a lens in addition to the half mirror 7a. Further, the signal light L3 emitted from the first end 31 of the light guide member 3 passes through the half mirror 7a of the optical member 7 and reaches the photodetector 5b.

The half mirror 7a has a function of spatially separating the optical paths of the laser beam L1 and the signal beam L3. As a specific example, the half mirror 7a can be configured by a dichroic mirror that switches between transmission and reflection depending on the wavelength band. In this embodiment, the half mirror 7a is configured to reflect the laser beam L1 and transmit the signal beam L3, but it may also be configured to transmit the laser beam L1 and reflect the signal beam L3.

(4) Driving device The driving device 5a receives an AC voltage from the AC power source P1 and supplies a driving current I1 to the light source 6. Specifically, the drive device 5a includes a power supply circuit 51 that converts an AC voltage into a DC voltage and outputs a drive current I1, and an output control circuit 52 that controls the power supply circuit 51. Note that the AC power source P1 is, for example, a commercial power source with a nominal voltage of 100 V or 200 V and a frequency of 50 Hz or 60 Hz.

The power supply circuit 51 is preferably a switching power supply circuit having a power factor correction function. For example, a switching power supply circuit includes an AC/DC conversion circuit and a DC/DC conversion circuit. The AC/DC conversion circuit is preferably a step-up chopper circuit or a buck-boost chopper circuit having a power factor correction function. In particular, the AC/DC conversion circuit is preferably an isolated flyback type converter circuit. The DC/DC conversion circuit is preferably a constant current controlled chopper circuit. Note that the DC/DC conversion circuit uses a step-down type circuit such as a step-down chopper circuit when the voltage of the light source 6 is lower than the output voltage of the AC/DC conversion circuit. On the other hand, if the voltage of the light source 6 is higher than the output voltage of the AC/DC conversion circuit, a boost type circuit such as a boost chopper circuit is used. Further, if the voltage of the light source 6 is sometimes higher and sometimes lower than the output voltage of the AC/DC conversion circuit, a buck-boost type circuit such as a buck-boost chopper circuit is used.

Further, the switching power supply circuit may be configured with a single stage converter (SS converter). The SS converter is a one-converter type converter (voltage conversion is performed once) that has the functions of a power factor correction circuit and an AC/DC converter.

The output control circuit 52 adjusts the drive current I1 by controlling the power supply circuit 51. That is, the drive device 5a has a dimming function that adjusts the amount of laser light L1 by making the drive current I1 variable.

(5) Light Guide Member The light guide member 3 is, for example, an optical fiber, and optically connects the light source device 2 and the lamp 4. The core diameter of the light guide member 3 is, for example, 400 μm. Note that the core diameter of the light guide member 3 may be 5 mm or less. Laser light L1 emitted from the light source 6 and condensed by the optical member 7 enters the first end 31 of the light guide member 3. The laser beam L1 is transmitted from the first end 31 of the light guide member 3 through the interior of the light guide member 3, and is emitted from the second end 32 of the light guide member 3.

(6) Lamp The laser beam L1 emitted from the second end 32 of the light guide member 3 enters the lamp 4. The lamp 4 houses a wavelength conversion member 4a inside a cylindrical lamp main body 4b with both ends open.

The wavelength conversion member 4a is a member in which a phosphor is mixed into a translucent material. The phosphor is, for example, a yellow phosphor. The yellow phosphor is, for example, Y ₃ Al ₅ O ₁₂ activated with Ce or Ba ₂ SiO ₄ activated with Eu. The phosphor is excited by a portion of the blue laser light L1 and emits yellow light. The wavelength conversion member 4a generates white light, which is a mixed color light of the remaining blue laser light L1 and yellow light, as wavelength converted light. The lamp 4 further includes at least one optical component, and controls the distribution of the white light generated by the wavelength conversion member 4a, and most of the white light is irradiated from the lamp 4 into the illumination space as illumination light L2. .

Further, a part of the white light enters the second end 32 of the light guide member 3 as the signal light L3. The signal light L3 that has entered the second end 32 is transmitted through the light guide member 3 and exits from the first end 31 of the light guide member 3.

(7) Photodetection device The photodetection device 5b includes an optical sensor 53 and an abnormality detection section 54.

The signal light L3 emitted from the first end 31 of the light guide member 3 passes through the half mirror 7a of the optical member 7 and reaches the optical sensor 53. The optical sensor 53 outputs an electrical signal Y1 according to the amount of the received signal light L3. That is, the optical sensor 53 detects the laser light L1 emitted from the light source 6 through the light guide member 3 and reflected by the lamp 4 as the signal light L3.

As shown in FIG. 3, the optical sensor 53 includes a photoelectric conversion element 531 and a current-voltage conversion section (hereinafter referred to as an IV conversion section) 532. The photoelectric conversion element 531 is, for example, a photodetection element such as a photodiode, and outputs a detection current according to the amount of received signal light L3. The IV converter 532 includes a current amplifier, a resistor, and the like, amplifies the detected current, converts the amplified detected current into a voltage, and outputs the converted voltage as an electrical signal Y1. That is, the electrical signal Y1 is a voltage signal, and the larger the amount of signal light L3, the larger the value of the detected current and the higher the voltage value of the electrical signal Y1. The optical sensor 53 is electrically connected to the abnormality detection section 54, and the electrical signal Y1 is output to the abnormality detection section 54.

The light receiving path of the optical sensor 53 is provided with an optical filter that transmits white light and attenuates light other than white light. Therefore, the optical sensor 53 can receive the white signal light L3 while hardly receiving any light other than the white signal light L3.

The abnormality detection unit 54 receives the electrical signal Y1 and detects an abnormality in the lighting system 1. Abnormalities in the illumination system 1 include abnormalities in the light guide member 3, abnormalities in the light source 6 (light emitting element 6a), and abnormalities in the wavelength conversion member 4a. The output control circuit 52 controls the power supply circuit 51 based on the abnormality detection result.

(8) Controller The output control circuit 52 and the abnormality detection section 54 are configured by the controller 5c. The controller 5c may be at least one control IC (Integrated Circuit) or a computer system.

A computer system includes, as its main hardware configuration, a processor that operates according to a program. The type of processor does not matter as long as it can implement the functions of the output control circuit 52 and the abnormality detection section 54 by executing a program. A processor is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or a large scale integration (LSI). Here, they are called IC or LSI, but the name changes depending on the degree of integration, and may also be called system LSI, VLSI (very large scale integration), or ULSI (ultra large scale integration). Field programmable gate arrays (FPGAs), which are programmed after the LSI is manufactured, or reconfigurable logic devices that can reconfigure the interconnections within the LSI or set up circuit sections within the LSI, may also be used for the same purpose. I can do it. A plurality of electronic circuits may be integrated on one chip or may be provided on a plurality of chips. A plurality of chips may be integrated into one device, or may be provided in a plurality of devices. The program is recorded on a computer-readable non-transitory storage medium such as a ROM, optical disk, or hard disk drive. The program may be stored in advance on a non-transitory recording medium, or may be supplied to the non-transitory recording medium via a wide area communication network including the Internet.

In the computer system, each function of the output control circuit 52 and the abnormality detection unit 54 in the present disclosure is realized by a processor executing a program.

(9) Feedback Control The operation of the lighting system 1 will be described below.

First, when AC power from the AC power supply P1 is input to the lighting system 1, the output control circuit 52 controls the power supply circuit 51 to supply the drive current I1 to the light source 6. The plurality of light emitting elements 6a of the light source 6 emit blue laser light L1 by driving current I1. The laser beam L1 passes through the optical member 7 and the light guide member 3 and reaches the wavelength conversion member 4a of the lamp 4. The wavelength conversion member 4a generates white light (wavelength converted light) from the blue laser light L1. The lamp 4 irradiates most of the white light into the illumination space as illumination light L2. A part of the white light passes through the light guide member 3 and the optical member 7 and reaches the optical sensor 53 of the optical detection device 5b as the signal light L3.

The signal light L3 is the same white light as the illumination light L2 that is actually irradiated into the illumination space, and includes information regarding the amount of light of the illumination light L2. That is, the larger the amount of illumination light L2, the larger the amount of signal light L3. Therefore, the larger the amount of illumination light L2, the higher the voltage value of electrical signal Y1, and the smaller the amount of illumination light L2, the lower the voltage value of electrical signal Y1. That is, information on the amount of illumination light L2 is fed back to the lighting device 5 as signal light L3.

The output control circuit 52 monitors the amount of illumination light L2 emitted by the light source 6 based on the voltage value of the electrical signal Y1. Then, the output control circuit 52 performs feedback control to make the drive current I1 match the target current by controlling the power supply circuit 51 so that the voltage value of the electric signal Y1 matches the target voltage value. The target voltage value may be a predetermined fixed value or a variable value corresponding to a dimming signal received from the outside. The output control circuit 52 can perform dimming control by making the target voltage value variable.

In this embodiment, the optical sensor 53 is located on the first end 31 side with respect to the light guide member 3. On the other hand, the wavelength conversion member 4a is located on the second end 32 side with respect to the light guide member 3. That is, the optical sensor 53 and the wavelength conversion member 4a are respectively positioned with the light guide member 3 in between. Then, the laser beam L1 passes through the inside of the light guide member 3 from the first end 31 and is emitted from the second end 32. The signal light L3 passes through the inside of the light guide member 3 from the second end 32 and exits from the first end 31. Therefore, the optical sensor 53 can detect the state of the illumination light L3 (white light) generated apart from the optical sensor 53 with the light guide member 3 in between, not in the vicinity of the lamp 4 but in the vicinity of the driving device 5a. Therefore, even if the total length of the light guide member 3 becomes longer, the optical sensor 53 can be placed near the drive device 5a, and furthermore, the signal line for transmitting the electric signal Y1 can be made shorter. As a result, the lighting system 1, the light source device 2, and the lighting device 5 of this embodiment can include the optical sensor 53 and have a simplified configuration.

(10) Abnormality Detection The abnormality detection unit 54 detects an abnormality in the lighting system 1 based on the electrical signal Y1. Abnormalities in the illumination system 1 include abnormalities in the light guide member 3, abnormalities in the wavelength conversion member 4a, and abnormalities in the light source 6 (light emitting element 6a). The output control circuit 52 controls the power supply circuit 51 based on the abnormality detection result.

The abnormality detection unit 54 performs abnormality detection processing at the initial stage when the light source 6 is turned on, including when the power is turned on, and during the steady state when the light source 6 is turned on. The abnormality detection unit 54 monitors the voltage value of the electrical signal Y1.

An abnormality in the light guide member 3 means, for example, that the light guide member 3 is disconnected, the light guide member 3 is detached from the light source device 2, or the light guide member 3 is detached from the lamp 4. When such an abnormality occurs in the light guide member 3, the signal light L3 may leak out from the disconnected portion of the light guide member 3, or the signal light L3 may not be transmitted to the light source device 2. Therefore, the amount of signal light L3 that reaches the optical sensor 53 when the light guide member 3 is abnormal is greatly reduced compared to when it is normal. As a result, the voltage value of the electric signal Y1 when the light guide member 3 is abnormal is lower than the voltage value of the electric signal Y1 when the light guide member 3 is normal.

The abnormality of the wavelength conversion member 4a is, for example, damage, chipping, peeling, or falling off of the wavelength conversion member 4a. When the wavelength conversion member 4a is abnormal, the amount of signal light L3 that enters the second end 32 of the light guide member 3 is significantly reduced compared to when it is normal. That is, the voltage value of the electrical signal Y1 when the wavelength conversion member 4a is abnormal is much lower than the voltage value of the electrical signal Y1 when the wavelength conversion member 4a is normal.

An abnormality in the light source 6 is not only a defect in which the light emitting element 6a does not emit the laser beam L1 because the driving current I1 does not flow through the light emitting element 6a, but also a failure in which the driving current I1 flows through the light emitting element 6a, but the light emitting element 6a does not emit the laser beam L1. This also includes an oscillation failure in which a problem occurs in the oscillation operation of the light emitting element 6a and the light emitting element 6a does not emit the laser beam L1. Furthermore, the state in which the light emitting element 6a does not emit light includes not only a state in which the light emitting element 6a does not emit any laser light L1, but also a state in which the light emitting element 6a emits light other than the expected laser light L1. An abnormality in the light source 6 is caused by an abnormality in at least one light emitting element 6a among the plurality of light emitting elements 6a. When the light source 6 is abnormal, the amount of signal light L3 emitted from the first end 31 of the light guide member 3 is lower than when it is normal. However, when the light source 6 is abnormal, there is a low possibility that all of the plurality of light emitting elements 6a will become abnormal, and a high possibility that some of the plurality of light emitting elements 6a will become abnormal. For example, when the light source 6 includes four light emitting elements 6a, there is a relatively high possibility that one or two of the four light emitting elements 6a will become abnormal.

Therefore, the voltage value of the electric signal Y1 when the light guide member 3, the wavelength conversion member 4a, or the light source 6 is abnormal is lower than the voltage value of the electric signal Y1 when the light guide member 3, the wavelength conversion member 4a, or the light source 6 is normal. However, as described above, the voltage value of the electric signal Y1 when the light guide member 3 or the wavelength conversion member 4a is abnormal is lower than the voltage value of the electric signal Y1 when the light source 6 is abnormal. In other words, if the ratio of the amount of decrease in the voltage value to the voltage value (normal value) of the electrical signal Y1 during normal times is defined as the rate of decrease, then the rate of decrease when the light source 6 is abnormal is equal to the rate of decrease when the light source 6 is abnormal. The rate of decline is smaller than that at the time of the change.

Specifically, FIG. 4A shows the voltage waveform of the electrical signal Y1 before and after an abnormality occurs in the light guide member 3 or the wavelength conversion member 4a. Before time t1 when an abnormality occurs in the light guide member 3 or the wavelength conversion member 4a, the voltage value of the electric signal Y1 is a normal value Va. When an abnormality occurs in the light guiding member 3 or the wavelength converting member 4a at time t1, the voltage value of the electric signal Y1 decreases from the normal value Va by a reduction amount ΔV1 to become an abnormal value V1. At this time, the voltage value decrease rate R1 becomes ΔV1/Va. On the other hand, FIG. 4B shows the voltage waveform of the electrical signal Y1 before and after the occurrence of an abnormality in the light source 6. Before time t2 when an abnormality occurs in the light source 6, the voltage value of the electric signal Y1 is a normal value Va. When an abnormality occurs in the light source 6 at time t2, the voltage value of the electrical signal Y1 decreases from the normal value Va by a reduction amount ΔV2 to become an abnormal value V2. At this time, the voltage value decrease rate R2 becomes ΔV2/Va. The amount of decrease ΔV2 is smaller than the amount of decrease ΔV1, and the rate of decrease R2 is smaller than the rate of decrease R1. In this embodiment, it is assumed that the reduction rate R1 exceeds 50% and the reduction rate R2 becomes 50% or less. For example, when the light source 6 includes four light emitting elements 6a, if one light emitting element 6a becomes abnormal, the reduction rate R2 becomes 25%, and if two light emitting elements 6a become abnormal, the reduction rate R2 becomes 50%.

The abnormality detection unit 54 periodically determines the rate of decrease in the voltage value of the electrical signal Y1. The abnormality detection unit 54 can grasp the dimming level of the light source 6 based on the dimming signal received from the outside, and stores data of a normal value Va corresponding to the dimming level in a data table or the like in advance in a memory or the like. Read from. The higher the dimming level, the larger the normal value Va. The abnormality detection unit 54 determines the rate of decrease from the voltage value of the electrical signal Y1 and the normal value Va.

The abnormality detection unit 54 then determines a first threshold value of the reduction rate used to determine the presence or absence of an abnormality, and a reduction rate used to determine between an abnormality in the light guide member 3 or the wavelength conversion member 4a and an abnormality in the light source 6. Each data of the second threshold value is stored in advance in a memory or the like. The first threshold is a value smaller than the second threshold. The abnormality detection unit 54 determines that an abnormality has occurred when the rate of decrease is equal to or higher than the first threshold, and then compares the rate of decrease with the second threshold. The abnormality detection unit 54 detects an abnormality in the light source 6 if the rate of decrease is less than or equal to the second threshold. The abnormality detection unit 54 detects an abnormality in the light guide member 3 or the wavelength conversion member 4a if the rate of decrease exceeds the second threshold value. For example, the first threshold value is set to about several percent to 10%, and the second threshold value is set to about 50%.

In this way, the abnormality detection unit 54 can detect an abnormality in the light guide member 3, an abnormality in the wavelength conversion member 4a, and an abnormality in the light source 6 (light emitting element 6a) based on the voltage value of the electric signal Y1. . Then, the abnormality detection section 54 delivers the abnormality detection result to the output control circuit 52.

The output control circuit 52 controls the power supply circuit 51 based on the abnormality detection result, and reduces the drive current I1 when an abnormality occurs. For example, if an abnormality in the light guide member 3 or the wavelength conversion member 4a is detected, the output control circuit 52 sets the drive current I1 to zero and stops the light source 6 from emitting the laser light L1. For example, if an abnormality in the light source 6 (light emitting element 6a) is detected, the output control circuit 52 reduces the drive current I1 to reduce the amount of laser light L1 emitted from the light source 6. Further, if an abnormality is detected in either the light guide member 3 or the wavelength conversion member 4a, or the light source 6, the output control circuit 52 sets the drive current I1 to zero and stops the light source 6 from emitting the laser beam L1. It may be stopped.

Further, if an abnormality is detected in either the light guide member 3, the wavelength conversion member 4a, or the light source 6, the output control circuit 52 intermittently outputs the drive current I1 to blink the laser light L1. It's okay. At this time, the output control circuit 52 can tell the surroundings whether an abnormality has occurred in the light guide member 3 or the wavelength conversion member 4a or the light source 6 by changing the blinking pattern depending on the content of the detected abnormality. Can be reported.

In this way, the light source device 2 can reduce the light intensity of the laser beam L1, blink or stop outputting the laser beam L1 when an abnormality is detected. Moreover, since the illumination light L2 is reduced, blinked, or stopped when the light intensity of the laser beam L1 is reduced, blinks, or the output of the laser beam L1 is stopped, it is possible to notify the surroundings of the occurrence of an abnormality.

(First modification)
FIG. 5 shows the configuration of the light source device 2 of this modification. The illumination lighting device 5 of the light source device 2 of this modification further includes an abnormal element identifying section 8, and this point differs from the above-described embodiment. In this modification, the same components as those in the above-described embodiment are given the same reference numerals, and the description thereof will be omitted.

The abnormal element identification unit 8 is provided between the power supply circuit 51 and the light source 6, as shown in FIG. As shown in FIG. 6, the abnormal element identifying section 8 includes a processing section 81 and a plurality of (four in the illustrated example) switches 82. The abnormal element identifying unit 8 identifies an abnormal light emitting element 6a from the plurality of light emitting elements 6a.

(11-1) Switches The plurality of switches 82 are respectively connected in parallel to the plurality of light emitting elements 6a. Each switch 82 is, for example, a semiconductor relay (solid state relay), and includes a light emitting diode 82a as a light emitting element and a phototransistor 82b as a light receiving element. The phototransistors 82b of the plurality of switches 82 are connected in series between the output terminals of the power supply circuit 51. Further, in each switch 82, a light emitting diode 82a is connected to the processing section 81, and a phototransistor 82b is connected in parallel to the light emitting element 6a. The anode of the light emitting diode 82a is connected to the processing section 81, and the cathode of the light emitting diode 82a is electrically connected to the low voltage side output end of the power supply circuit 51. Each switch 82 turns on and off the phototransistor 82b under the control of the processing unit 81 for the light emitting diode 82a. Hereinafter, turning on and off the phototransistor 82b may be referred to as turning on and off the switch 82.

The plurality of switches 82 have one-to-one correspondence with the plurality of light emitting elements 6a, and are connected in parallel to the corresponding light emitting elements 6a. In the example of FIG. 6, the plurality of light emitting elements 6a are composed of a first light emitting element 61, a second light emitting element 62, a third light emitting element 63, and a fourth light emitting element 64. The plurality of switches 82 include a first switch 821, a second switch 822, a third switch 823, and a fourth switch 824. The first switch 821 corresponds to the first light emitting element 61 and the second switch 822 corresponds to the second light emitting element 62. The third switch 823 corresponds to the third light emitting element 63, and the fourth switch 824 corresponds to the fourth light emitting element 64.

In each switch 82, when the phototransistor 82b is in an off state, a drive current I1 flows through the corresponding light emitting element 6a. On the other hand, when the phototransistor 82b is in the on state, both ends of the corresponding light emitting element 6a are short-circuited, so that the drive current I1 does not flow through the corresponding light emitting element 6a. For example, when the phototransistor 82b of the first switch 821 is in an off state, the drive current I1 flows through the first light emitting element 61. On the other hand, when the phototransistor 82b of the first switch 821 is in the on state, the drive current I1 does not flow through the first light emitting element 61. Regarding each relationship between the second switch 822 and the second light emitting element 62, the third switch 823 and the third light emitting element 63, and the fourth switch 824 and the fourth light emitting element 64, the above-mentioned first switch 821 and the first light emitting element The relationship is the same as that with element 61.

(11-2) Processing Unit The processing unit 81 is, for example, a microcontroller, and controls a plurality of switches 82. More specifically, the processing unit 81 individually controls on/off of the plurality of switches 82 to control current supply to each of the plurality of light emitting elements 6a.

When the abnormality detection unit 54 detects an abnormality in the light source 6, the processing unit 81 sequentially turns on the plurality of switches 82 one by one from the off state for a certain period of time. The processing unit 81 monitors changes in the amount of signal light L3 received by the optical sensor 53 based on the electrical signal Y1. Then, when the switch 82 is turned on, if the light intensity of the signal light L3 does not change (if the voltage value of the electric signal Y1 does not decrease), the processing unit 81 responds to the switch 82 that corresponds to the turned on state. It is determined that the light emitting element 6a is abnormal. The details will be explained below.

When the abnormality detection unit 54 detects an abnormality in the light source 6, the processing unit 81 turns on the plurality of switches 82 one by one for a certain period of time, and monitors the voltage value of the electric signal Y1. When the light emitting element 6a corresponding to the switch 82 in the on state is normal, the light emitting element 6a does not emit laser light. Therefore, the amount of laser light L1 emitted by the light source 6 decreases, the amount of signal light L3 also decreases, and the voltage value of the electrical signal Y1 decreases. On the other hand, the abnormal light emitting element 6a does not emit laser light regardless of whether the corresponding switch 82 is on or off. Therefore, the amount of laser light L1 does not change before and after the switch 82 corresponding to the abnormal light emitting element 6a is turned on. As a result, the amount of signal light L3 does not change, and the voltage value of electrical signal Y1 does not change. Therefore, the processing unit 81 identifies the light emitting element 6a in which the voltage value of the electric signal Y1 does not change before and after the switch 82 is turned on, as an abnormal light emitting element 6a.

In this way, by turning on the plurality of switches 82 corresponding to the plurality of light emitting elements 6a one by one and monitoring the voltage value of the electric signal Y1, an abnormal light emitting element is detected from among the plurality of light emitting elements 6a. 6a can be specified.

In this modification, the processing unit 81 detects a light emission failure when the amount of change in the voltage value of the electric signal Y1 is within the third threshold before and after the switch 82 is turned on. The data of the third threshold value is stored in advance in a memory or the like.

Further, when detecting an abnormality in any of the light emitting elements 6a, the processing unit 81 turns on the switch 82 corresponding to the abnormal light emitting element 6a to short-circuit both ends of the abnormal light emitting element 6a. For example, when the processing unit 81 detects a light emission failure of the second light emitting element 62, it turns on the second switch 822 corresponding to the second light emitting element 62 to short-circuit both ends of the second light emitting element 62. The drive current I1 flows through the first light emitting element 61, the phototransistor 82b of the second switch 822, the third light emitting element 63, and the fourth light emitting element 64. In other words, the drive current I1 does not flow through the second light emitting element 62.

As a result, the abnormal light emitting element 6a among the plurality of light emitting elements 6a is turned off, and use can be continued with the abnormal light emitting element 6a electrically removed from the plurality of light emitting elements 6a. Further, it is possible to notify the surroundings which light emitting element 6a is abnormal among the plurality of light emitting elements 6a. Furthermore, since the drive current I1 no longer flows to the abnormal light emitting element 6a, the heat generation of the abnormal light emitting element 6a can be reduced.

(Second modification)
The optical sensor 53 may be a photodetecting element other than a photodiode. The optical sensor 53 may be, for example, a phototransistor, a solar cell, a CdS cell, or the like.

The light emitting element 6a may emit laser light L1 of a color other than blue, and the wavelength conversion member 4a may emit light of a color other than yellow using the laser light L1. Further, the wavelength-converted light may be other than white light. Furthermore, the light emitted by the light emitting element 6a is not limited to laser light.

The circuit configuration of the power supply circuit 51 is not limited to a specific circuit configuration as long as it can output the DC drive current I1.

Each of the above-mentioned modifications also provides the same effects as the embodiment.

The embodiments and modifications described above are only some of the various embodiments and modifications of the present disclosure. Furthermore, the embodiments and modifications can be modified in various ways depending on the design, etc., as long as the objective of the present disclosure can be achieved.

(mode)
The embodiments and modifications described above disclose the following aspects.

The light source device (2) according to the first aspect is used together with a light guide member (3) that guides light between a first end (31) and a second end (32), and a wavelength conversion member (4a). It will be done. The wavelength conversion member (4a) converts the first light (L1) that has entered the first end (31) and exited from the second end (32) into second light (L1) having a different wavelength from the first light (L1). wavelength converted light). The light source device (2) includes one or more light emitting elements (6a), an optical sensor (53), and a drive device (5a). The one or more light emitting elements (6a) are supplied with a driving current (I1) and thereby emit first light (L1) that is incident on the first end (31). The optical sensor (53) detects the signal light (L3) of the second light that is incident on the second end (32) and transmitted to the first end (31). The drive device (5a) supplies a drive current (I1) to one or more light emitting elements (6a), and controls the drive current (I1) using the detection result of the signal light (L3).

The light source device (2) described above includes the optical sensor (53) and can have a simplified configuration.

In the light source device (2) according to the second aspect, in the first aspect, the driving device (5a) controls the driving current (I1) so that the amount of light of the signal light (L3) becomes a predetermined value. is preferred.

In the light source device (2) described above, feedback control of the drive current (I1) is possible.

In the light source device (2) according to the third aspect, the one or more light emitting elements (6a) in the first or second aspect are preferably a plurality of light emitting elements (6a).

The light source device (2) described above includes a plurality of light emitting elements (6a) and a light sensor (53), and can have a simplified configuration.

In the third aspect, the light source device (2) according to the fourth aspect includes a wavelength conversion member (4a), a light guide member (3), and a plurality of It is preferable to further include an abnormality detection section (54) that detects each abnormality of the light emitting element (6a).

The light source device (2) described above can detect two or more abnormalities with a simple configuration.

In the light source device (2) according to the fifth aspect, in the fourth aspect, the abnormality detection unit (54) detects the wavelength conversion member (4a) and the light guide member when the decrease rate exceeds the threshold (second threshold). It is preferable to detect an abnormality in at least one of (3). Further, it is preferable that the abnormality detection unit (54) detects abnormality in some of the plurality of light emitting elements (6a) if the rate of decrease is equal to or less than a threshold value.

The light source device (2) described above can distinguish between an abnormality in at least one of the wavelength conversion member (4a) and the light guide member (3) and an abnormality in a part of the plurality of light emitting elements (6a).

In the light source device (2) according to the sixth aspect, in the fifth aspect, when the abnormality detection unit (54) detects an abnormality in a part of the plurality of light emitting elements (6a), the light source device (2) It is preferable to further include an abnormal element identifying section (8) that identifies an abnormal light emitting element (6a) from ). The abnormal element identification unit (8) turns off the abnormal light emitting element (6a).

The light source device (2) described above can notify the surroundings of an abnormal light emitting element (6a) among the plurality of light emitting elements (6a). Moreover, abnormal heat generation of the light emitting element (6a) can be reduced.

In the light source device (2) according to the seventh aspect, in the sixth aspect, the abnormal element identifying section (8) includes a plurality of switches (82) and a processing section (81). The plurality of switches (82) have one-to-one correspondence with the plurality of light emitting elements (6a), and are connected in parallel to the corresponding light emitting elements (6a). If the signal light (L3) does not change when the plurality of switches (82) are sequentially turned on one by one, the processing section (81) turns one of the plurality of light emitting elements (6a) into the on state. It is determined that the light emitting element (6a) corresponding to the switch (82) is an abnormal light emitting element.

The light source device (2) described above can detect an abnormal light emitting element (6a) among the plurality of light emitting elements (6a).

In the light source device (2) according to the eighth aspect, in the fifth aspect, the drive device (5a) is configured such that the abnormality detection section (54) is connected to at least one of the wavelength conversion member (4a) and the light guide member (3). It is preferable to control the drive current (I1) so that all of the plurality of light emitting elements (6a) are turned off when an abnormality is detected.

The light source device (2) described above can notify the surroundings of an abnormality. Moreover, abnormal heat generation of the light emitting element (6a) can be reduced.

The lighting device (5) according to the ninth aspect is used together with a light guide member (3), a wavelength conversion member (4a), and one or more light emitting elements (6a). The light guide member (3) guides light between a first end (31) and a second end (32). The wavelength conversion member (4a) converts the first light (L1) that has entered the first end (31) and exited from the second end (32) into second light (L1) having a different wavelength from the first light (L1). wavelength converted light). One or more light emitting elements (6a) emit first light (L1) by being supplied with a drive current (I1). The lighting device (5) includes an optical sensor (53) and a drive device (5a). The optical sensor (53) detects the second light that is incident on the second end (32) and transmitted to the first end (31) as signal light (L3). The drive device (5a) supplies a drive current (I1) to the light emitting element (6a) and controls the drive current (I1) using the detection result of the signal light (L3).

The above-described lighting device (5) includes the optical sensor (53) and can have a simplified configuration.

The illumination system (1) according to the tenth aspect includes a light guide member (3), a wavelength conversion member (4a), one or more light emitting elements (6a), a light sensor (53), and a drive device ( 5a). The light guide member (3) guides light between a first end (31) and a second end (32). The wavelength conversion member (4a) converts the first light (L1) that has entered the first end (31) and exited from the second end (32) into second light (L1) having a different wavelength from the first light (L1). wavelength converted light). One or more light emitting elements (6a) emit first light (L1) by being supplied with a drive current (I1). The optical sensor (53) detects the signal light (L3) of the second light that is incident on the second end (32) and transmitted to the first end (31). The drive device (5a) supplies a drive current (I1) to the light emitting element (6a) and controls the drive current (I1) using the detection result of the signal light (L3).

The above-described lighting system (1) includes the optical sensor (53) and can have a simplified configuration.

1 illumination system 2 light source device 3 light guide member 31 first end 32 second end 4a wavelength conversion member 5 illumination lighting device 5a drive device 53 optical sensor 54 abnormality detection section 6a light emitting element 8 abnormal element identification section 81 processing section 82 switch L1 Laser light (first light)
I1 Drive current L3 Signal light

Claims (7)

A light guide member that guides light between a first end and a second end, and a light guide member that guides light between a first end and a second end, and a second light having a wavelength different from the first light. A light source device used together with a wavelength conversion member that converts into light,
a plurality of light emitting elements that emit the first light incident on the first end by being supplied with a drive current;
an optical sensor that detects signal light that is incident on the second end and transmitted to the first end of the second light;
a drive device that supplies the drive current to the plurality of light emitting elements and controls the drive current using a detection result of the signal light;
an abnormality detection unit that detects each abnormality of the wavelength conversion member, the light guide member, and the plurality of light emitting elements based on the rate of decrease in the amount of light of the signal light,
The abnormality detection section includes:
Detecting each abnormality in the wavelength conversion member, the light guide member, and the plurality of light emitting elements by comparing the rate of decrease with a first threshold value and a second threshold value,
The first threshold value and the second threshold value are less than 100%,
The first threshold is a value smaller than the second threshold,
If the rate of decline is greater than or equal to the first threshold and less than or equal to the second threshold, detecting an abnormality in some of the plurality of light emitting elements;
If the rate of decrease exceeds the second threshold, an abnormality in at least one of the wavelength conversion member and the light guide member is detected.
Light source device. The light source device according to claim 1, wherein the drive device controls the drive current so that the amount of light of the signal light becomes a predetermined value. further comprising an abnormal element identifying unit that identifies an abnormal light emitting element from the plurality of light emitting elements when the abnormality detecting unit detects an abnormality in a part of the plurality of light emitting elements,
The abnormal element identification unit turns off the abnormal light emitting element.
The light source device according to claim 1 or 2. The abnormal element identification unit is
a plurality of switches in one-to-one correspondence with the plurality of light emitting elements and connected in parallel to the corresponding light emitting elements;
If the signal light does not change when the plurality of switches are sequentially turned on one by one, the light emitting element corresponding to the switch turned on among the plurality of light emitting elements emits the abnormal light. a processing unit that determines that the device is an element;
The light source device according to claim 3. The driving device controls the driving current so as to turn off all of the plurality of light emitting elements when the abnormality detection section detects an abnormality in at least one of the wavelength conversion member and the light guide member. The light source device according to any one of items 1 to 4. A light guide member that guides light between a first end and a second end, converts the first light that is incident on the first end and exits from the second end into second light that has a different wavelength from the first light. An illumination lighting device used with a wavelength conversion member that converts to
an optical sensor that detects the second light incident on the second end and transmitted to the first end as signal light;
a drive device that supplies the drive current to the light emitting element and controls the drive current using a detection result of the signal light;
an abnormality detection unit that detects each abnormality of the wavelength conversion member, the light guide member, and the plurality of light emitting elements based on the rate of decrease in the amount of light of the signal light,
The abnormality detection section includes:
Detecting each abnormality in the wavelength conversion member, the light guide member, and the plurality of light emitting elements by comparing the rate of decrease with a first threshold value and a second threshold value,
The first threshold value and the second threshold value are less than 100%,
The first threshold is a value smaller than the second threshold,
If the rate of decline is greater than or equal to the first threshold and less than or equal to the second threshold, detecting an abnormality in some of the plurality of light emitting elements;
If the rate of decrease exceeds the second threshold, an abnormality in at least one of the wavelength conversion member and the light guide member is detected.
Lighting device. a light guide member that guides light between a first end and a second end;
a wavelength conversion member that converts first light that enters the first end and exits from the second end into second light that has a different wavelength from the first light;
a plurality of light emitting elements that emit the first light by being supplied with a drive current;
an optical sensor that detects signal light that is incident on the second end and transmitted to the first end of the second light;
a drive device that supplies the drive current to the light emitting element and controls the drive current using a detection result of the signal light;
an abnormality detection unit that detects each abnormality of the wavelength conversion member, the light guide member, and the plurality of light emitting elements based on the rate of decrease in the amount of light of the signal light,
The abnormality detection section includes:
Detecting each abnormality in the wavelength conversion member, the light guide member, and the plurality of light emitting elements by comparing the rate of decrease with a first threshold value and a second threshold value,
The first threshold value and the second threshold value are less than 100%,
The first threshold is a value smaller than the second threshold,
If the rate of decline is greater than or equal to the first threshold and less than or equal to the second threshold, detecting an abnormality in some of the plurality of light emitting elements;
If the rate of decrease exceeds the second threshold, an abnormality in at least one of the wavelength conversion member and the light guide member is detected.
lighting system.

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