JP2020194677A - Photodetector, lighting device, and lighting system - Google Patents

Abstract

To provide a photodetector capable of detecting an abnormality of an optical sensor, and an illumination lighting device, and an illumination system.SOLUTION: A photodetector 5b includes a first optical sensor 53 and a second optical sensor 54 for detecting signal light L3. A second received amount which is the received amount of the signal light L3 received by the second optical sensor 54 is smaller than the amount of light of the first received amount which is a received amount of the signal light L3 received by the first optical sensor 53.SELECTED DRAWING: Figure 1

Description

The present disclosure generally relates to photodetectors, lighting devices, and lighting systems. More specifically, the present disclosure relates to a photodetector, a lighting device, and a lighting system having a photosensor that detects light emitted from a light source.

In the solid-state lighting device of Patent Document 1, the light source unit emits blue laser light, and the blue laser light is guided to the light emitting unit by the optical fiber and absorbed by the wavelength conversion layer of the light emitting unit. The wavelength conversion layer absorbs the blue laser light and emits the yellow wavelength conversion light. The light emitting unit emits white light, which is a mixture of blue laser light and yellow wavelength conversion light. A part of the white light becomes return light, propagates in the optical fiber, and is incident on the light receiving portion. The light receiving unit is composed of a first light receiving unit that detects the return light transmitted through the blue light cut filter and a second light receiving unit that detects the return light transmitted through the yellow light cut filter.

The solid-state lighting device of Patent Document 1 has a function of self-diagnosing an abnormality of white light, and the ratio of the output electric signal of the first light receiving unit and the output electric signal of the second light receiving unit is out of a predetermined range. When becomes, the drive of the light source unit is stopped.

Japanese Unexamined Patent Publication No. 2013-97033

The solid-state lighting device of Patent Document 1 described above includes two optical sensors (a first light receiving unit and a second light receiving unit) for detecting light. However, it was not possible to detect an abnormality in the optical sensor.

The present disclosure has been made in view of the above points, and an object of the present disclosure is to provide a photodetector, a lighting device, and a lighting system capable of detecting an abnormality of an optical sensor.

The photodetector according to one aspect of the present disclosure includes a first photosensor and a second photosensor that detect light, and the second photodetector, which is the amount of light received by the second photosensor, is the above. It is smaller than the light amount of the first light receiving amount, which is the light receiving amount of the light received by the first light sensor.

The photodetector according to one aspect of the present disclosure includes a first photosensor that detects light and outputs a first electrical signal, and a second photosensor that detects the light and outputs a second electrical signal. The first electric signal is an analog signal that continuously changes with respect to a change in the amount of light, and the second electric signal is a binary digital signal that switches according to the amount of light.

The illumination lighting device according to one aspect of the present disclosure includes the above-mentioned photodetector and a drive device for supplying electric power to a light source.

The lighting system according to one aspect of the present invention includes the above-mentioned lighting lighting device, the light source, and a lamp that emits illumination light using the light source light emitted by the light source.

The photodetector, the lighting device, and the lighting system according to the above aspect of the present disclosure can detect an abnormality of the optical sensor.

FIG. 1 is a schematic view of a lighting system including a photodetector according to an embodiment. FIG. 2 is an external view of the same lighting system. FIG. 3 is a block diagram of the same photodetector. FIG. 4A is an output characteristic diagram of the first optical sensor of the same photodetector. FIG. 4B is an output characteristic diagram of the second optical sensor. FIG. 5 is a flowchart illustrating the operation of the same photodetector.

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

As shown in FIG. 1, the lighting system 1 includes a light source device 2, a light guide member 3, and a lamp 4. The light source device 2 emits the laser beam L1. The laser light L1 enters the first end 31 of the light guide member 3, passes through the inside of the light guide member 3, and emits light from the second end 32 of the light guide member 3. The laser light L1 emitted from the second end 32 is converted into wavelength conversion light by the wavelength conversion member 4a of the lamp 4, and most of the wavelength conversion light is irradiated from the lamp 4 to the illumination space as illumination light L2. A part of the wavelength conversion light is incident on 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 from the first end 31 of the light guide member 3. Exit.

The light source device 2 includes an illumination lighting device 5, a light source 6, an optical member 7, and a condenser lens 8. The lighting lighting device 5 lights the light source 6 by supplying a direct current drive current I1 to the light source 6. The light source 6 emits the laser beam L1 when the drive current I1 is supplied. The laser beam L1 emitted from the light source 6 is incident on 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, the optical member 7, and the condenser lens 8. The light source device 2 is used together with the light guide member 3 and the lamp tool 4.

The illumination lighting device 5 includes a drive device 5a and a light detection device 5b. The drive device 5a receives an AC voltage from the AC power supply P1 and supplies the 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 is incident on the second end 32 of the light guide member 3, passes through the inside of the light guide member 3, and is emitted from the first end 31 of the light guide member 3.

The lighting system 1 is used, for example, in an underwater luminaire that radiates light from underwater, or in a headlight of an automobile.

(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 to which the drive current I1 is supplied from the drive device 5a radiate, for example, blue laser light L1 as light source light. The electrical connection relationship between the plurality of light emitting elements 6a is a series connection, but the connection relationship is not limited to this. The electrical connection relationship of the plurality of light emitting elements 6a may be a parallel connection or a connection relationship in which a series connection and a parallel connection are combined. Further, the light source 6 may include one light emitting element 6a. Each of the plurality of light emitting elements 6a included in the light source 6 is not limited to the laser diode, but is another solid light emitting element (semiconductor light emitting element) such as an LED (Light Emitting Diode) and an organic EL (Organic ElectroLuminescence, OEL). You may.

(3) Optical member The optical member 7 includes a half mirror 7a as shown in FIG. 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. Then, the optical member 7 collects the laser beam L1 and causes it to enter the first end 31 of the light guide member 3. In addition to the half mirror 7a, the optical member 7 may include other optical components such as a mirror and a lens. 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 the condenser lens 8 and reaches the photodetector 5b.

The half mirror 7a has a function of spatially separating the optical paths of the laser light L1 and the signal light 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 the present embodiment, the half mirror 7a is configured to reflect the laser light L1 and transmit the signal light L3, but it may be configured to transmit the laser light L1 and reflect the signal light L3.

(4) Drive device The drive device 5a receives an AC voltage from the AC power supply P1 and supplies the drive 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. The AC power supply P1 is, for example, a commercial power supply having 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 improving function. For example, the switching power supply circuit has an AC / DC conversion circuit and a DC / DC conversion circuit. The AC / DC conversion circuit is preferably a boost chopper circuit or a buck-boost chopper circuit having a power factor improving function. In particular, the AC / DC conversion circuit is preferably an isolated flyback type converter circuit. The DC / DC conversion circuit is preferably a chopper circuit that is controlled by a constant current. When the voltage of the light source 6 is lower than the output voltage of the AC / DC conversion circuit, the DC / DC conversion circuit uses a step-down type circuit such as a step-down chopper circuit. On the other hand, when the voltage of the light source 6 is higher than the output voltage of the AC / DC conversion circuit, a step-up type circuit such as a step-up chopper circuit is used. When the voltage of the light source 6 is higher or 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 composed of a single stage converter (SS converter). The SS converter is a one-converter type (one-time voltage conversion) converter having a power factor improving circuit function and an AC / DC converter function.

The output control circuit 52 adjusts the drive current I1 by controlling the power supply circuit 51. It is preferable that the drive device 5a has a dimming function for adjusting the amount of light of the laser beam 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 tool 4. The core diameter of the light guide member 3 is, for example, 400 μm. The core diameter of the light guide member 3 may be 5 mm or less. Then, the laser beam L1 radiated from the light source 6 and focused by the optical member 7 is incident on the first end 31 of the light guide member 3. The laser light L1 is transmitted from the first end 31 of the light guide member 3 to the inside 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 is incident on the lamp 4. The lamp 4 houses a wavelength conversion member 4a inside a tubular lamp body 4b having both ends open.

The wavelength conversion member 4a is a member in which a phosphor is mixed with a translucent material. The phosphor is, for example, a yellow phosphor. The yellow fluorophore 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 part of the blue laser beam L1 and emits yellow light. The wavelength conversion member 4a generates white light, which is a mixed color of the remaining blue laser light L1 and yellow light, as wavelength conversion light. The lamp 4 further includes at least one optical component, controls the distribution of white light generated by the wavelength conversion member 4a, and most of the white light is emitted from the lamp 4 as illumination light L2 into the illumination space. ..

Further, a part of the white light is incident on the second end 32 of the light guide member 3 as the signal light L3. The signal light L3 incident on the second end 32 is transmitted inside the light guide member 3 and emitted from the first end 31 of the light guide member 3. The signal light L3 is a mixed light of a blue laser light L1 and a yellow light, and is light including the laser light L1.

(7) Condensing Lens The condensing lens 8 is arranged between the optical member 7 and the light detection device 5b, and converges the signal light L3 transmitted through the half mirror 7a of the optical member 7 to cause the light detection device. It is a condensing member that irradiates 5b.

Further, it is preferable that the condensing lens 8 has a function of an optical filter that transmits white light and attenuates light other than white light in combination with the above-mentioned condensing function. Due to the function of the optical filter of the condenser lens 8, the white signal light L3 can be received with almost no light other than the light detection device 5b and the white signal light L3.

(8) Photodetector The photodetector 5b includes a first optical sensor 53, a second optical sensor 54, and an abnormality detection unit 55.

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 the condenser lens 8 and reaches the first optical sensor 53 and the second optical sensor 54. The first optical sensor 53 outputs an electric signal Y1 according to the amount of light of the signal light L3. The second optical sensor 54 outputs an electric signal Y2 according to the amount of light of the signal light L3. That is, the first optical sensor 53 and the second optical sensor 54 detect the light emitted by the laser beam L1 emitted from the light source 6 through the light guide member 3 and reflected by the lamp 4 as the signal light L3, respectively.

As shown in FIG. 3, the first optical sensor 53 includes a photoelectric conversion element 531 and an amplification unit 532. The photoelectric conversion element 531 is an optical detection element such as a photodiode, and outputs a detection current corresponding to the amount of light of the signal light L3. The amplification unit 532 has a current amplifier, a resistor, and the like, amplifies the detection current, converts the amplified detection current into a voltage, and outputs the converted voltage as the first electric signal Y1. That is, the first electric signal Y1 is a voltage signal. The first optical sensor 53 is electrically connected to the abnormality detection unit 55, and the first electric signal Y1 is output to the abnormality detection unit 55.

FIG. 4A is an output characteristic diagram of the first optical sensor 53, showing the relationship between the light amount Q0 of the signal light L3 and the first voltage value Vy1 which is the voltage value of the first electric signal Y1. As the amount of light Q0 increases from 0 (zero), the first voltage value Vy1 also increases linearly from 0. When the light amount Q0 exceeds the saturated light amount Qa, the first voltage value Vy1 becomes constant at the saturated voltage value Va. That is, the amplification unit 532 functions as an analog amplifier, and if the light intensity Q0 is between 0 and Qa, the first optical sensor 53 operates in a linear region in which the first voltage value Vy1 is proportional to the light intensity Q0. The larger the amount of light Q0, the higher the first voltage value Vy1. However, when the light amount Q0 exceeds the saturated light amount Qa, the first optical sensor 53 operates in the saturated region where the output of the first light sensor 53 is saturated, and the first voltage value Vy1 reaches a plateau (constant) at the saturated voltage value Va. become. By operating the first optical sensor 53 not only in the linear region but also in the saturated region in this way, the dynamic range of the light amount Q0 of the signal light L3 can be widened. In FIG. 4A, the minimum saturated light amount Qa1 and the standard saturated light amount Qa2 are exemplified as the saturated light amount Qa, and the minimum saturated voltage value Va1 and the standard saturated voltage value Va2 are exemplified as the saturated voltage value Va. The minimum saturated light amount Qa1, the standard saturated light amount Qa2, the minimum saturated voltage value Va1, and the standard saturated voltage value Va2 will be described in detail in (10-1) Anomaly detection.

As shown in FIG. 3, the second optical sensor 54 includes a photoelectric conversion element 541 and an amplification unit 542. The photoelectric conversion element 541 is an optical detection element such as a photodiode, and outputs a detection current according to the amount of light of the signal light L3. The amplification unit 542 has a current amplifier, a resistor, and the like, amplifies the detection current, converts the amplified detection current into a voltage, and outputs the converted voltage as a second electric signal Y2. That is, the second electric signal Y2 is a voltage signal. The second optical sensor 54 is electrically connected to the abnormality detection unit 55, and the second electric signal Y2 is output to the abnormality detection unit 55.

FIG. 4B is an output characteristic diagram of the second optical sensor 54, showing the relationship between the light amount Q0, which is the light amount of the signal light L3, and the second voltage value Vy2, which is the voltage value of the second electric signal Y2. If the amount of light Q0 is 0 or more and less than the threshold value Qb, the second voltage value Vy2 becomes the L (Low) level. If the amount of light Q0 is equal to or greater than the threshold value Qb, the second voltage value Vy2 becomes the H (High) level. That is, the amplification unit 542 functions as a comparator, and switches the second voltage value Vy2 to either of two values (H, L) according to the magnitude relationship between the light amount Q0 and the threshold value Qb.

The abnormality detection unit 55 receives the first electric signal Y1 and the second electric signal Y2, and performs an abnormality detection process for determining the presence or absence of an abnormality in the lighting system 1. The abnormality of the lighting system 1 includes an abnormality of the light guide member 3 and an abnormality of the first optical sensor 53. If there is no abnormality, the abnormality detection unit 55 generates a lighting permission signal.

When the output control circuit 52 receives the lighting permission signal from the abnormality detection unit 55, the output control circuit 52 can drive the power supply circuit 51 to emit the laser beam L1. If the output control circuit 52 does not receive the lighting permission signal from the abnormality detection unit 55, the output control circuit 52 stops the power supply circuit 51 and stops the radiation of the laser beam L1. That is, if the output control circuit 52 receives the lighting permission signal, the emission of the laser light L1 (driving the power supply circuit 51) is permitted, and if the output control circuit 52 does not receive the lighting permission signal, the emission of the laser light L1 (driving the power supply circuit 51) is permitted. ) Is prohibited.

(9) The controller output control circuit 52 and the abnormality detection unit 55 are composed of the controller 5c. The controller 5c may be any of at least one control IC (Integrated Circuit) and a computer system.

A computer system includes a processor that operates according to a program as a main hardware configuration. The type of processor does not matter as long as it can realize each function of the output control circuit 52 and the abnormality detection unit 55 by executing the program. The processor is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or an LSI (large scale integration). Here, it is called an IC or an LSI, but the name changes depending on the degree of integration, and it may be called a system LSI, a VLSI (very large scale integration), or a ULSI (ultra large scale integration). Field programmable gate arrays (FPGAs), which are programmed after the LSI is manufactured, or reconfigurable logical devices that can reconfigure the junction relationships inside the LSI or set up circuit partitions inside the LSI should also be used for the same purpose. Can be done. The 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 in one device, or may be provided in a plurality of devices. The program is recorded on a non-temporary recording medium such as a computer-readable ROM, optical disc, or hard disk drive. The program may be stored in a non-temporary recording medium in advance, or may be supplied to the non-temporary recording medium via a wide area communication network including the Internet or the like.

In a computer system, the functions of the output control circuit 52 and the abnormality detection unit 55 in the present disclosure are realized by the processor executing the program.

(10) Lighting control The lighting control by the controller 5c will be described below.

First, when the AC power of the AC power supply P1 is applied to the lighting system 1, the output control circuit 52 controls the power supply circuit 51 to drive the power supply circuit 51 and 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 the drive 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 conversion light) from the blue laser light L1. The lamp 4 irradiates the illumination space with most of the white light as the illumination light L2. A part of the white light passes through the light guide member 3, the optical member 7, and the condenser lens 8 as the signal light L3, and reaches the first optical sensor 53 and the second optical sensor 54 of the photodetector 5b.

The signal light L3 is the same white light as the illumination light L2 that is actually irradiated to the illumination space, and includes information on the amount of the illumination light L2. That is, the larger the amount of illumination light L2, the larger the amount of light Q0 of the signal light L3. That is, the information on the amount of light of the illumination light L2 is fed back to the illumination lighting device 5 as the signal light L3.

Then, the abnormality detection unit 55 performs the abnormality detection process based on the first electric signal Y1 and the second electric signal Y2. The output control circuit 52 controls the power supply circuit 51 based on the result of the abnormality detection process.

(10-1) Abnormality detection The abnormality detection unit 55 performs abnormality detection processing at the initial stage of lighting of the light source 6 including when the power is turned on and at the steady time when the light source 6 is lit. The abnormality detection unit 55 detects the abnormality of the light guide member 3 and the abnormality of the first optical sensor 53 by monitoring the voltage values Vy1 and Vy2 of the first electric signal Y1 and the second electric signal Y2.

The abnormality of 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 the light guide member 3 is abnormal, the signal light L3 may leak to the outside from the disconnection 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 light Q0 at the time of abnormality of the light guide member 3 is significantly reduced as compared with the case of normal. As a result, the first voltage value Vy1 when the light guide member 3 is abnormal is significantly lower than the first voltage value Vy1 when the light guide member 3 is normal.

Therefore, the controller 5c stores the data of the first voltage value Vy1 (hereinafter referred to as the first normal voltage value) at the normal time in the memory or the like in advance for each dimming level. The abnormality detection unit 55 reads the data of the first normal voltage value corresponding to the current dimming level from the memory, and compares the first voltage value Vy1 with the first normal voltage value. If the first voltage value Vy1 is 50% or less of the first normal voltage value, the abnormality detection unit 55 detects an abnormality in the light guide member 3. Hereinafter, the decrease of the first voltage value Vy1 to 50% or less of the first normal voltage value may be referred to as "50% down" of the first voltage value Vy1.

However, the first voltage value Vy1 of the first electric signal Y1 may be fixed to the saturation voltage value Va regardless of the magnitude of the light amount Q0 due to electrostatic destruction of the first optical sensor 53, a failure mode, or the like. .. If the first voltage value Vy1 is fixed to the saturation voltage value Va, the abnormality detecting unit 55 cannot detect the abnormality of the light guide member 3. Therefore, the abnormality detection unit 55 detects the electrostatic breakdown of the first optical sensor 53, the failure mode, and the like as an abnormality of the first optical sensor 53 based on both the first electric signal Y1 and the second electric signal Y2. ..

Specifically, if the light amount Q0 of the signal light L3 is sufficiently small enough to operate in the linear region if it is a normal first optical sensor 53, but if the first voltage value Vy1 is the saturation voltage value Va, then There is a possibility that the first optical sensor 53 has an abnormality. Therefore, in the abnormality detection unit 55, the first voltage value Vy1 of the first electric signal Y1 is equal to or higher than the saturation voltage value Va (first value), and the second voltage value Vy2 of the second electric signal Y2 is L level ( If it is less than or equal to (second value), it is determined that the first optical sensor 53 may have an abnormality.

Therefore, the threshold value Qb is set as shown in FIGS. 4A and 4B.

First, the saturation voltage value Va varies from individual to individual of the first optical sensor 53. In FIG. 4A, the output characteristic of the first optical sensor 53 at which the saturation voltage value Va is the minimum saturation voltage value Va1 is defined as the output characteristic C1. The output characteristic of the first optical sensor 53 in which the saturation voltage value Va is the standard saturation voltage value Va2 is defined as the output characteristic C2. The magnitude relationship between the minimum saturation voltage value Va1 and the standard saturation voltage value Va2 is Va1 <Va2. Further, assuming that the saturated light amount Qa corresponding to the minimum saturated voltage value Va1 is the minimum saturated light amount Qa1 and the saturated light amount Qa corresponding to the standard saturated voltage value Va2 is the standard saturated light amount Qa2, the minimum saturated light amount Qa1 and the standard saturated light amount Qa2 The magnitude relationship is Qa1 <Qa2. In addition, in FIG. 4A and FIG. 4B, the saturated light amount Qa is represented by the ratio of the light amount Q0 to the maximum value.

Specifically, the variation in the power supply voltage of the first optical sensor 53 is ± 2%, the variation in the saturation voltage of the photoelectric conversion element 531 is -13% to 0%, and the accuracy of AD conversion of the first voltage value Vy1 is ± 0. Assuming 15V, the minimum saturation voltage value Va1 is represented by Equation 1, and the minimum saturation light amount Qa1 is represented by Equation 2. Then, the threshold value Qb is set to a value slightly smaller than the minimum saturated light amount Qa1. That is, the threshold value Qb is set to a value less than the minimum saturated light amount Qa1 in consideration of the variation in the saturated light amount Qa.
Va1 = Va2 ・ (4.11 / 5) ……… Equation 1
Qa1 = Qa2 ・ (21/25) ……… Equation 2
For example, assuming that the standard saturation voltage value Va2 is 5V, the minimum saturation voltage value Va1 is 4.11V based on Equation 1. Assuming that the standard saturated light amount Qa2 is 25%, the minimum saturated light amount Qa1 is 21% based on the equation 2. The threshold Qb is set to 20%, which is slightly smaller than the minimum saturated light amount Qa1 (21%). In this case, the correspondence between the light guide member 3, the first optical sensor 53, the second optical sensor 54, and the amount of light Q0 and the first voltage value Vy1 and the second voltage value Vy2 is as follows from the first mode to the first mode. It becomes one of 16 modes. In the second optical sensor 54, the second voltage value Vy2 of the second electric signal Y2 may be fixed at the H level regardless of the magnitude of the light amount Q0 due to electrostatic breakdown, an abnormality such as a failure mode, or the like. is there.

(1st mode) If "light guide member 3: normal, 1st optical sensor 53: normal, 2nd optical sensor 54: normal, light amount Q0: 20% or more", "1st voltage value Vy1: 4V or more, In addition, it becomes "Va or less, second voltage value Vy2: H level".

(Second mode) If "light guide member 3: normal, first light sensor 53: normal, second light sensor 54: normal, light amount Q0: less than 20%", "first voltage value Vy1: 0.3V" Above, and less than 4V, the second voltage value Vy2: L level ”.

(Third mode) If "light guide member 3: normal, first optical sensor 53: abnormal, second optical sensor 54: normal, light amount Q0: 20% or more", "first voltage value Vy1: Va constant, The second voltage value Vy2: H level ”.

(Fourth mode) If "light guide member 3: normal, first light sensor 53: abnormal, second light sensor 54: normal, light amount Q0: less than 20%", "first voltage value Vy1: Va constant, Second voltage value Vy2: L level ”.

(Fifth mode) If "light guide member 3: normal, first optical sensor 53: normal, second optical sensor 54: abnormal, light amount Q0: 20% or more", "first voltage value Vy1: 4V or more, In addition, it becomes "Va or less, second voltage value Vy2: H level".

(6th mode) If "light guide member 3: normal, first optical sensor 53: normal, second optical sensor 54: abnormal, light amount Q0: less than 20%", "first voltage value Vy1: 0.3V" Above, and less than 4V, the second voltage value Vy2: H level ”.

(7th mode) If "light guide member 3: normal, first optical sensor 53: abnormal, second optical sensor 54: abnormal, light amount Q0: 20% or more", "first voltage value Vy1: Va constant, The second voltage value Vy2: H level ”.

(8th mode) If "light guide member 3: normal, first optical sensor 53: abnormal, second optical sensor 54: abnormal, light amount Q0: less than 20%", "first voltage value Vy1: Va constant, The second voltage value Vy2: H level ”.

(9th mode) If "light guide member 3: abnormal, first optical sensor 53: normal, second optical sensor 54: normal, light amount Q0: 20% or more", "first voltage value Vy1: 50% down" , Second voltage value Vy2: L level ”.

(10th mode) If "light guide member 3: abnormal, first optical sensor 53: normal, second optical sensor 54: normal, light amount Q0: less than 20%", "first voltage value Vy1: 50% down" , Second voltage value Vy2: L level ”.

(11th mode) If "light guide member 3: abnormal, first optical sensor 53: abnormal, second optical sensor 54: normal, light amount Q0: 20% or more", "first voltage value Vy1: Va constant, Second voltage value Vy2: L level ”.

(12th mode) If "light guide member 3: abnormal, first optical sensor 53: abnormal, second optical sensor 54: normal, light amount Q0: less than 20%", "first voltage value Vy1: Va constant, Second voltage value Vy2: L level ”.

(13th mode) If "light guide member 3: abnormal, first optical sensor 53: normal, second optical sensor 54: abnormal, light amount Q0: 20% or more", "first voltage value Vy1: 50% down" , Second voltage value Vy2: H level ”.

(14th mode) If "light guide member 3: abnormal, first optical sensor 53: normal, second optical sensor 54: abnormal, light amount Q0: less than 20%", "first voltage value Vy1: 50% down" , Second voltage value Vy2: L level ”.

(15th mode) If "light guide member 3: abnormality, first light sensor 53: abnormality, second light sensor 54: abnormality, light amount Q0: 20% or more", "first voltage value Vy1: Va constant, The second voltage value Vy2: H level ”.

(16th mode) If "light guide member 3: abnormality, first light sensor 53: abnormality, second light sensor 54: abnormality, light amount Q0: less than 20%", "first voltage value Vy1: Va constant, The second voltage value Vy2: H level ”.

Then, the abnormality detection process by the abnormality detection unit 55 is performed as shown in FIG.

The abnormality detection unit 55 determines whether or not the first voltage value Vy1 is reduced by 50% while the light source 6 is lit (whether or not the first voltage value Vy1 is reduced to 50% or less of the first normal voltage value). Is determined (S1). If the first voltage value Vy1 is reduced by 50%, the abnormality detection unit 55 determines that the light guide member 3 is abnormal, does not generate a lighting permission signal, and stops the radiation of the laser beam L1. (S2). If the first voltage value Vy1 does not decrease by 50%, the abnormality detection unit 55 determines whether the first voltage value Vy1 is equal to or higher than the first value K1 and the second voltage value Vy2 is less than the second value K2. (S3). If the first voltage value Vy1 is equal to or higher than the first value K1 and the second voltage value Vy2 is less than the second value K2, the abnormality detection unit 55 is at least one of the first optical sensor 53 or the light guide member 3. It is determined that one of them is abnormal (the abnormality is detected), the lighting permission signal is not generated, and the lighting disabling process for stopping the radiation of the laser beam L1 is performed (S2). If the first voltage value Vy1 is less than the first value K1 or the second voltage value Vy2 is the second value K2 or more, the abnormality detection unit 55 repeats the process of step S1.

That is, if the first voltage value Vy1 is 50% down, the abnormality detection unit 55 determines that the light guide member 3 is abnormal and does not generate a lighting permission signal. That is, the abnormality detection unit 55 detects an abnormality in the light guide member 3 if the first voltage value Vy1 is reduced by 50% regardless of the second voltage value Vy2.

Further, the abnormality detection unit 55 compares the first voltage value Vy1 with the first value K1 and the second voltage value Vy2 with the second value K2. For example, the first value K1 is a value “Va1-α” obtained by subtracting the constant α from the minimum saturation voltage value Va1. The second value K2 is a voltage value lower than the H level and higher than the L level. If the first voltage value Vy1 is equal to or higher than the first value K1 and the second voltage value Vy2 is less than the second value K2, the abnormality detection unit 55 causes an abnormality in at least one of the first optical sensor 53 and the light guide member 3. As is, the lighting permission signal is not generated.

Therefore, if the first voltage value Vy1: 4V or more and Va or less and the second voltage value Vy2: H level as in the first mode and the fifth mode, the first voltage value Vy1 is the first value K1. As described above, the second voltage value Vy2 becomes the second value K2 or more. At this time, the abnormality detection unit 55 generates a lighting permission signal. In the fifth mode, the second optical sensor 54 is abnormal, but the abnormality detecting unit 55 can detect the abnormality of the light guide member 3 by the first optical sensor 53, so that it is not necessary to stop the radiation of the laser beam L1. ..

If the first voltage value Vy1: 0.3V or more and less than 4V and the second voltage value Vy2: L level as in the second mode, the first voltage value Vy1 is less than the first value K1 and the second. The voltage value Vy2 is less than the second value K2. At this time, the abnormality detection unit 55 generates a lighting permission signal.

If the first voltage value Vy1: Va is constant and the second voltage value Vy2: H level, as in the third mode, the seventh mode, the eighth mode, the fifteenth mode, and the sixteenth mode, the first voltage value Vy1 has a first value of K1 or more, and a second voltage value of Vy2 has a second value of K2 or more. At this time, the abnormality detection unit 55 generates a lighting permission signal. In the seventh mode and the eighth mode, the second optical sensor 54 is abnormal, but the abnormality detection unit 55 can detect the abnormality of the light guide member 3 by the first optical sensor 53, so that the emission of the laser beam L1 is stopped. There is no need to let it. In the 15th mode and the 16th mode, the light guide member 3, the first optical sensor 53, and the second optical sensor 54 are abnormal, but it is unlikely that all of them become abnormal at the same time, and the light guide member 3 or the first When the optical sensor 53 becomes abnormal, the lighting permission signal is not generated. That is, it is unlikely that the 15th mode and the 16th mode will be set.

If the first voltage value Vy1: Va is constant and the second voltage value Vy2: L level as in the fourth mode, the eleventh mode, and the twelfth mode, the first voltage value Vy1 is the first value K1 or more. Moreover, the second voltage value Vy2 is less than the second value K2. At this time, the abnormality detection unit 55 does not generate a lighting permission signal. In the fourth mode, the first optical sensor 53 is abnormal, and in the eleventh and twelfth modes, the light guide member 3 is abnormal.

If the first voltage value Vy1: 0.3V or more and less than 4V and the second voltage value Vy2: H level as in the sixth mode, the first voltage value Vy1 is less than the first value K1 and the second. The voltage value Vy2 becomes the second value K2 or more. At this time, the abnormality detection unit 55 generates a lighting permission signal.

If the first voltage value is Vy1: 50% down as in the 9th mode, the 10th mode, the 13th mode, and the 14th mode, it is determined that the light guide member 3 is abnormal, and a lighting permission signal is generated. do not do. That is, the abnormality detection unit 55 detects an abnormality in the light guide member 3 if the first voltage value Vy1 is reduced by 50% regardless of the second voltage value Vy2.

As described above, in the 4th mode and the 9th to 14th modes, the abnormality detection unit 55 detects the abnormality of the first optical sensor 53 or the abnormality of the light guide member 3 and does not generate a lighting permission signal. .. If the output control circuit 52 does not receive the lighting permission signal, the power supply circuit 51 is stopped (the drive current I1 is set to 0), and the radiation of the laser beam L1 is stopped (prohibited).

(10-2) Light Received Amount In the present embodiment, the second light received amount which is the received signal amount of the signal light L3 by the second optical sensor 54 is the first received light amount which is the received light amount of the signal light L3 by the first light sensor 53. Smaller. This configuration can be realized as follows.

As shown in FIG. 3, the condenser lens 8 converges the incident signal light L3 at the focal position X1 and irradiates the photodetector 5b. The first optical sensor 53 is arranged at a position closer to the focal position X1 than the second optical sensor 54. In FIG. 3, the first optical sensor 53 and the second optical sensor 54 are arranged side by side in a direction orthogonal to the incident direction of the signal light L3. The first optical sensor 53 is positioned so as to overlap the focal position X1, and the second optical sensor 54 is located away from the focal position X1. Therefore, the second light receiving amount of the second optical sensor 54 far from the focal position X1 is smaller than the first light receiving amount of the first light sensor 53 near the focal position X1.

Further, as the light amount Q0 of the signal light L3 increases, the first light receiving amount and the second light receiving amount increase. Therefore, as the first light receiving amount increases, the second light receiving amount increases. In particular, the second light receiving amount is preferably proportional to the first light receiving amount.

As described above, the photodetector 5b detects an abnormality in the first photosensor 53 by using the first photosensor 53 and the second photosensor 54 (two photosensors). At this time, by making the second light receiving amount of the second optical sensor 54 smaller than the first light receiving amount of the first light sensor 53, the output of the second light sensor 54 is less likely to be saturated. As a result, the abnormality detection process using the output of the second optical sensor 54 is easy not only when the second optical sensor 54 functions as a comparator but also when the second optical sensor 54 functions as an analog amplifier. become.

Further, as an optical spec required for the signal light L3, there is an SN ratio (Signal Noise Ratio) of the signal light L3. In the present embodiment, the signal intensity of the noise contained in the signal light L3 is preferably 20% or less of the signal intensity of the signal light L3. This optical spec is required for the first optical sensor 53 and the second optical sensor 54 which are arranged apart as described above.

(Modification example)
The photoelectric conversion elements 531 and 541 may be photodetector elements other than the photodiode. The photoelectric conversion elements 531 and 541 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 by the laser light L1. Further, the wavelength conversion light may be other than white light. Further, the light emitted by the light emitting element 6a is not limited to the laser light.

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

Further, the abnormality of the lighting system 1 detected by the abnormality detection unit 55 includes the abnormality of the light guide member 3, the abnormality of the first optical sensor 53, the abnormality of the light source 6 (light emitting element 6a), and the wavelength conversion member. At least one of the anomalies of 4a may be included. The abnormality of the light source 6 is not only a defect that the light emitting element 6a does not radiate the laser beam L1 because the driving current I1 does not flow through the light emitting element 6a, but also that the driving current I1 is flowing through the light emitting element 6a. It also includes an oscillation failure in which the light emitting element 6a does not emit the laser beam L1 due to a problem in the oscillation operation of the 6a. 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 light L1 at all, but also a state in which the light emitting element 6a emits light other than the assumed laser light L1. The abnormality of the wavelength conversion member 4a is, for example, breakage, chipping, peeling, or dropping of the wavelength conversion member 4a.

In each of the above modifications, the same effect as that of the embodiment is obtained.

The embodiments and modifications described above are only a part of the various embodiments and modifications of the present disclosure. Further, the embodiments and modifications can be variously changed according to the design and the like as long as the object of the present disclosure can be achieved.

(Aspect)
The following aspects are disclosed from the embodiments and modifications described above.

The photodetector (5b) according to the first aspect includes a first photosensor (53) and a second photosensor (54) that detect light (L3). The second light reception amount, which is the light reception amount of the light (L3) received by the second light sensor (54), is the light amount of the first light reception amount, which is the light reception amount of the light (L3) received by the first light sensor (53). Smaller.

The above-mentioned photodetector (5b) can detect an abnormality in the first optical sensor (53).

The photodetector (5b) according to the second aspect detects a first optical sensor (53) that detects light (L3) and outputs a first electric signal (Y1), and detects light (L3). It has a second optical sensor (54) that outputs two electrical signals (Y2). The first electric signal (Y1) is an analog signal that continuously changes with respect to a change in the amount of light (L3). The second electric signal (Y2) is a binary digital signal that switches according to the amount of light (L3).

The above-mentioned photodetector (5b) can detect an abnormality in the first optical sensor (53).

It is preferable that the photodetector (5b) according to the third aspect further includes an abnormality detection unit (55) in the second aspect. In the abnormality detection unit (55), the magnitude (Vy1) of the first electrical signal (Y1) is equal to or larger than the first value (K1), and the magnitude (Vy2) of the second electrical signal (Y2) is the second. If it is less than the value (K2), an abnormality is detected.

The above-mentioned photodetector (5b) is configured to use the first photosensor (53) and the second photosensor (54), and can detect an abnormality in the first photosensor (53).

In the photodetector (5b) according to the fourth aspect, in the second or third aspect, the second received amount, which is the received amount of the light (L3) received by the second optical sensor (54), is the first. It is preferably smaller than the first light receiving amount, which is the light receiving amount of the light (L3) received by the optical sensor (53).

The above-mentioned photodetector (5b) can detect an abnormality in the first optical sensor (53).

In the photodetector (5b) according to the fifth aspect, it is preferable that the second light receiving amount increases as the first light receiving amount increases in the fourth aspect.

The above-mentioned photodetector (5b) can accurately detect an abnormality in the first optical sensor (53).

In the photodetector (5b) according to the sixth aspect, in the fifth aspect, the second light receiving amount is preferably proportional to the first light receiving amount.

The above-mentioned photodetector (5b) can accurately detect an abnormality in the first optical sensor (53).

In any one of the first to sixth aspects of the photodetector (5b) according to the seventh aspect, the first optical sensor (53) and the second optical sensor (54) are arranged side by side. Is preferable.

The above-mentioned photodetector (5b) can accurately detect an abnormality in the first optical sensor (53).

The photodetector (5b) according to the eighth aspect has, in any one of the first to seventh aspects, a light collecting member (8) that concentrates the light (L3) at the focal position (X1). Further, the position of the first optical sensor (53), which is preferably provided, is preferably closer to the focal position (X1) than the position of the second optical sensor (54).

In the above-mentioned photodetector (5b), the light receiving amount of the second optical sensor (54) can be made smaller than the light receiving amount of the first light sensor (53).

In any one of the first to eighth aspects of the photodetector (5b) according to the ninth aspect, the light (L3) preferably includes a laser beam (L1).

The above-mentioned photodetector (5b) can detect an abnormality of the first photosensor (53) in the device that generates the laser beam (L1).

In the ninth aspect of the photodetector (5b) according to the tenth aspect, the light (L3) is wavelength-converted light obtained by subjecting the laser beam (L1) to wavelength conversion processing by the wavelength conversion member (4a). It is preferable to have.

The above-mentioned photodetector (5b) can detect an abnormality of the first optical sensor (53) in a device that generates wavelength-converted light.

The illumination lighting device (5) according to the eleventh aspect includes a light detection device (5b) according to any one of the first to tenth aspects, a drive device (5a) for supplying electric power to the light source (6), and the like. To be equipped.

The above-mentioned lighting device (5) can detect an abnormality in the first optical sensor (53).

The illumination system (1) according to the twelfth aspect uses the illumination lighting device (5) of the eleventh aspect, the light source (6), and the light source light (L1) emitted by the light source (6). It is provided with a lighting tool (4) that emits L2).

The above-mentioned lighting system (1) can detect an abnormality of the first optical sensor (53).

In the twelfth aspect, the lighting system (1) according to the thirteenth aspect may further include a light guide member (3) that guides the light (L3) from the lamp (4) to the photodetector (5b). preferable.

The above-mentioned lighting system (1) can detect an abnormality in the light guide member (3).

1 Lighting system 3 Light guide member 4 Lighting tool 4a Frequency conversion member 5 Lighting lighting device 5a Drive device 5b Photodetector 53 First light sensor 54 Second light sensor 55 Abnormality detection unit 6 Light source 8 Condensing lens (condensing member)
Y1 1st electric signal Y2 2nd electric signal Vy1 1st voltage value (magnitude of 1st electric signal)
Vy2 2nd voltage value (magnitude of 2nd electric signal)
Va saturation voltage value (first value)
X1 Focus position L1 Laser light (light source light)
L2 Illumination light L3 Signal light (light)

Claims (13)

It is equipped with a first optical sensor and a second optical sensor that detect light.
The second photodetector, which is the amount of light received by the second photosensor, is smaller than the amount of light received by the first photosensor, which is the amount of light received by the first photosensor. It has a first optical sensor that detects light and outputs a first electric signal, and a second optical sensor that detects the light and outputs a second electric signal.
The first electric signal is an analog signal that continuously changes with respect to a change in the amount of light, and the second electric signal is a binary digital signal that switches according to the amount of light. Detection device. The light of claim 2, further comprising an abnormality detection unit for detecting an abnormality if the magnitude of the first electrical signal is equal to or greater than the first value and the magnitude of the second electrical signal is less than the second value. Detection device. The second photodetection amount, which is the light reception amount of the light received by the second optical sensor, is smaller than the first light reception amount, which is the light reception amount of the light received by the first light sensor, according to claim 2 or 3. apparatus. The photodetector according to claim 4, wherein when the first light receiving amount increases, the second light receiving amount increases. The second light receiving amount is proportional to the first light receiving amount.
The optical detection device according to claim 5. The photodetector according to any one of claims 1 to 6, wherein the first optical sensor and the second optical sensor are arranged side by side. A condensing member that collects the light at the focal position is further provided.
The photodetector according to any one of claims 1 to 7, wherein the position of the first optical sensor is closer to the focal position than the position of the second optical sensor. The photodetector according to any one of claims 1 to 8, wherein the light includes laser light. The light detection device according to claim 9, wherein the light is wavelength conversion light obtained by subjecting the laser light to wavelength conversion processing by a wavelength conversion member. The photodetector according to any one of claims 1 to 10 and
A lighting device including a driving device that supplies electric power to a light source. The lighting device according to claim 11 and
With the light source
A lighting system including a lamp that emits illumination light using the light source light emitted by the light source. The lighting system according to claim 12, further comprising a light guide member that guides the light from the lamp to the light detection device.

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