WO2023008213A1

WO2023008213A1 - Lighting device and endoscope device

Info

Publication number: WO2023008213A1
Application number: PCT/JP2022/027732
Authority: WO
Inventors: 俊明竹中; 真太郎林; 史也八木; 省吾茂手木
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2021-07-29
Filing date: 2022-07-14
Publication date: 2023-02-02
Also published as: JP2023019546A

Abstract

A lighting device (1) is equipped with: an excitation source (6) which emits excitation light (L1): a fluorescent body (4a) which emits fluorescence upon receiving the excitation light (L1); an optical sensor (61) which uses the excitation light (L1) and/or the fluorescence as detection light (L3), and outputs a detection signal (s0) based on the detection light (L3); a mirror device (62) for outputting a plurality of output signals (s1-s3) on the basis of the detection signal (s0); a plurality of amplifiers (63) for amplifying the plurality of output signals (s1-s3) at different gains and outputting the plurality of amplified signals (sa-sc); and an abnormality determination unit (56) for determining whether an abnormality exists on the basis of the amplified signal among the plurality of amplified signals (sa-sc) which has the largest signal level, from among the amplified signals for which the signal level of the amplified signals (sa-sc) is no more than a prescribed threshold (Vth1) relative to the detection light (L3) amount.

Description

Lighting device and endoscope device

The present disclosure relates to a lighting device using a semiconductor light emitting device and an endoscope device.

Conventionally, lighting devices using semiconductor light-emitting elements are known (see, for example, Patent Document 1). The lighting device described in Patent Document 1 includes a detection circuit having a photoelectric conversion element that converts light into an electric signal and an amplifier that amplifies and outputs the electric signal, and an amplification factor switching that changes the amplification factor of the amplifier. and an abnormality determination unit that determines whether there is an abnormality based on the amplified electrical signal. In this lighting device, when the amplification factor is changed by the amplification factor switching unit, if the amount of change in the magnitude of the amplified electric signal is smaller than the determination threshold value, it is determined that an abnormality has occurred.

JP 2020-194679 A

In the lighting device described in Patent Literature 1, when the amplification factor of the amplifier is switched, there occurs a period during which an abnormality in the lighting device cannot be detected. Therefore, there is a problem that it is impossible to determine whether or not there is an abnormality in the lighting device.

Therefore, the present disclosure provides a lighting device or the like that can timely determine whether there is an abnormality.

In order to solve the above problems, the lighting device of the present disclosure includes an excitation source that emits excitation light, a phosphor that receives the excitation light and emits fluorescence, and at least one of the excitation light and the fluorescence. a photosensor for outputting a detection signal based on the detection light as detection light; a mirror device for outputting a plurality of output signals based on the detection signal; and amplifying the plurality of output signals with different gains, a plurality of amplifiers for outputting signals; and among the plurality of amplified signals, among the amplified signals, the signal level of the plurality of amplified signals with respect to the light amount of the detected light is equal to or lower than a predetermined threshold, and the signal level is the maximum. an abnormality determination unit that determines the presence or absence of an abnormality based on a certain amplified signal.

In order to solve the above problems, an endoscope apparatus according to the present disclosure includes the illumination device described above and an observation device for observing a subject.

According to the lighting device and the like of the present disclosure, it is possible to timely determine whether there is an abnormality.

FIG. 1 is a schematic diagram showing the configuration of a lighting device of a comparative example. FIG. 2 is a schematic diagram showing the configuration of the lighting device according to the embodiment. FIG. 3 is an external view showing the configuration of the lighting device according to the embodiment. FIG. 4 is a circuit diagram showing the configuration of the excitation source of the lighting device according to the embodiment. FIG. 5 is a block diagram showing the configuration of the optical sensor, mirror device, and amplifier of the lighting device according to the embodiment. FIG. 6 is a diagram showing the relationship between the amount of light detected by the optical sensor and the signal level of the amplified signal. FIG. 7 is a schematic diagram showing the configuration of an endoscope apparatus including the illumination device according to the embodiment.

(Summary of this disclosure)
An overview of the present disclosure will be described with reference to comparative examples.

FIG. 1 is a schematic diagram showing a lighting device 101 of a comparative example.

The lighting device 101 of the comparative example is a device that converts the wavelength of the excitation light L1 and emits the illumination light L2. As shown in the figure, the illumination device 101 includes a light source device 102 that outputs excitation light L1, a light guide member 103, and phosphors 104a.

The light guide member 103 guides the excitation light L1 output from the light source device 102 and emits it to the phosphor 104a. The phosphor 104a converts the excitation light L1 into light of a different wavelength and emits it. Specifically, the phosphor 104a fluoresces when the excitation light L1 is input, and diffuses and radiates, for example, light of a plurality of wavelengths that appears white as a whole. This radiated light is emitted as illumination light L2.

The lighting device 101 includes a detection circuit 160 that detects an abnormality in the phosphor 104a, and an abnormality determination unit 156 that determines whether the phosphor 104a is abnormal based on the detection result of the detection circuit 160. The detection circuit 160 includes an optical sensor 161 that receives part of the light emitted from the phosphor 104a as the detection light L3 and outputs a detection signal s0, and amplifies and outputs the detection signal s0 that is output from the optical sensor 161. and an amplifier circuit 163 for

Since the light emitted from the phosphor 104a has a wide dynamic range, if the scale (measure) of the detection circuit 160 is too small or too large, the amount of the detection light L3 may not be detected accurately. Therefore, in the comparative example, by switching the gain (amplification factor) of the amplifier circuit 163 when amplifying the detection signal s0 output from the optical sensor 161, the light amount of the detection light L3 can be read over a wide range. In the comparative example, the abnormality determination unit 156 reads the signal amplified by switching the gain, and determines whether or not the phosphor 104a is abnormal.

However, in the lighting device 101 of the comparative example, since the level of the amplified signal changes greatly when switching the gain of the amplifier circuit 163, it takes time for the signal level to stabilize after switching the gain. Therefore, in the comparative example, there is a period during which an abnormality of the phosphor 104a cannot be detected, and there is a problem that the presence or absence of an abnormality cannot be determined.

On the other hand, the illumination device of the present embodiment has a configuration in which the light amount of the detection light L3 can be read without switching the gain of the amplifier circuit. For example, in the lighting device of this embodiment, a plurality of output signals are generated from the detection signal s0 output from the photosensor, and each of the plurality of output signals is amplified with different gains. Then, among a plurality of amplified signals amplified with different gains, an amplified signal suitable for determining the presence or absence of an abnormality is used to determine the presence or absence of an abnormality. As a result, it is possible to suppress the occurrence of a period in which an abnormality of the lighting device cannot be detected, and it is possible to timely determine whether or not there is an abnormality.

Hereinafter, embodiments of the present disclosure will be described in detail using the drawings.

It should be noted that the embodiments described below all show one comprehensive or specific example of the present disclosure. Numerical values, shapes, materials, components, arrangement positions and connection forms of components, steps, order of steps, and the like shown in the following embodiments are examples, and are not intended to limit the present disclosure. In addition, among the constituent elements in the following embodiments, constituent elements that are not described in independent claims representing the highest concept will be described as arbitrary constituent elements.

(Embodiment)
A lighting device according to an embodiment will be described.

[1. Configuration of lighting device]
The configuration of the illumination device according to this embodiment will be described with reference to FIGS. 2 to 6. FIG.

2 and 3 are a block diagram and an external view, respectively, showing the configuration of the lighting device 1 according to the embodiment. FIG. 2 also shows the input power supply P1 together with the illumination device 1. The input power supply P<b>1 is a system power supply that supplies AC power to the lighting device 1 . The input power supply P1 is, for example, a commercial AC power supply.

The illumination device 1 is a device that emits illumination light L2, and as shown in FIGS. 2 and 3, includes a light source device 2, a light guide member 3, and a phosphor 4a. In addition, each component of the lighting device 1 may be integrated or may not be integrated. For example, the lighting device 1 may be arranged in one housing, or may be a combination of a plurality of distributed devices.

The light source device 2 is a device that emits excitation light L1. As shown in FIG. 2 , the light source device 2 has a lighting device 5 , an excitation source 6 and an optical member 7 . In this embodiment, the light source device 2 emits excitation light L1. The light source device 2 has a housing 2a as shown in FIG. 3, and the lighting device 5, the excitation source 6 and the optical member 7 shown in FIG. 2 are accommodated in the housing 2a.

The lighting device 5 is a device that lights by supplying power to the excitation source 6, and includes a driving device 5a, a light source switching section 54, a detection circuit 60, and an abnormality determination section 56. The driving device 5 a is a device for controlling power supplied to the excitation source 6 and has a power supply circuit 51 and an output control circuit 58 . The abnormality determination unit 56 and the output control circuit 58 are configured by the controller 5c.

Each component of the lighting device 1 will be described below.

[Excitation source]
The excitation source 6 includes one or more light emitting elements and emits excitation light L1. The configuration of the excitation source 6 according to this embodiment will be described below with reference to FIG.

4 is a circuit diagram showing the configuration of the excitation source 6 of the lighting device 1. FIG. 4 also shows a circuit diagram of the light source switching unit 54. As shown in FIG.

As shown in FIG. 4, the excitation source 6 includes four light emitting elements 6a-6d connected in series. Each of the light emitting elements 6a to 6d is not particularly limited as long as it is an element that emits light according to the power supplied. In the present embodiment, each of light emitting elements 6a to 6d is a semiconductor laser element that emits blue excitation light. As a result, the excitation source 6 emits excitation light L1, which is laser light. The electrical connection mode of the plurality of light emitting elements included in the excitation source 6 is not limited to series connection, and may be parallel connection or a combination of series connection and parallel connection. good. Further, the number of light emitting elements included in the excitation source 6 is not limited to four, and may be one or more. Moreover, each of the light-emitting elements included in the excitation source 6 is not limited to a semiconductor laser element, and may be another solid-state light-emitting element such as an LED (Light Emitting Diode) or an organic EL (Electro Luminescence) element.

[Light source switching part]
The light source switching unit 54 is a circuit that short-circuits both ends of each light emitting element included in the excitation source 6 . The light source switching section 54 has a plurality of switches 821 to 824 connected in parallel to the plurality of light emitting elements 6a to 6d, respectively. Each of the plurality of switches 821-824 is, for example, a semiconductor relay (in other words, solid state relay), and has a light emitting diode 82a as a light emitting element and a phototransistor 82b as a light receiving element.

In each switch, when the phototransistor 82b is in the off state, the driving current I1 flows through the corresponding light emitting element. On the other hand, when the phototransistor 82b is on, both ends of the corresponding light emitting element are short-circuited, so that the drive current I1 does not flow through the corresponding light emitting element.

[Power supply circuit]
The power supply circuit 51 is a circuit that supplies power to the excitation source 6 . The power supply circuit 51 converts and outputs the voltage of the power output from the input power supply P1. In this embodiment, the switching power supply circuit converts AC power output from the input power supply P1 into DC power. The power supply circuit 51 may be a switching power supply circuit having a power factor correction function.

[Optical member]
As shown in FIG. 2, the optical member 7 is a member that guides the excitation light L1 output from the excitation source 6 to the optical system. The optical member 7 may be composed of optical components such as mirrors and lenses. In this embodiment, the optical system is the light guide member 3 , and the optical member 7 reflects the excitation light L<b>1 output from the excitation source 6 toward the first end 3 a of the light guide member 3 . The optical member 7 further converges the excitation light L<b>1 to enter the first end 3 a of the light guide member 3 .

[Light guide member]
The light guide member 3 is an example of an optical system that receives the excitation light L1 and irradiates the phosphor 4a with the excitation light L1. In this embodiment, the light guide member 3 is an optical fiber that guides the excitation light L1, and optically connects the light source device 2 and the phosphor 4a. The core diameter of the light guide member 3 is, for example, 400 μm. In addition, the core diameter of the light guide member 3 should be 5 mm or less. The excitation light L<b>1 emitted from the excitation source 6 and condensed by the optical member 7 is incident on the first end 3 a of the light guide member 3 . The excitation light L1 is transmitted through the interior of the light guide member 3 from the first end 3 a of the light guide member 3 and emitted from the second end 3 b of the light guide member 3 .

[Phosphor]
The phosphor 4a is a wavelength conversion member that converts the excitation light L1 into illumination light L2 having a wavelength different from that of the excitation light L1 and emits the illumination light L2. In the present embodiment, the excitation light L1 emitted from the second end 3b of the light guide member 3 is applied to the phosphor 4a. In this embodiment, the phosphor 4a is a member in which a fluorescent material is mixed with a translucent material. The phosphor 4a 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 4a is excited by part of the blue excitation light L1 and emits yellow light as the illumination light L2. The phosphor 4a generates white light, which is mixed color light of the remaining blue excitation light L1 and yellow light. Most of the white light generated by the phosphor 4a is irradiated to the illumination space as the illumination light L2. A portion of the white light, excluding most of the white light, enters a detection circuit 60, which will be described later.

[Detection circuit]
The detection circuit 60 is a circuit that detects an abnormality in the lighting device 1 . The detection circuit 60 is arranged on the side of the phosphor 4a. The detection circuit 60 includes a photosensor 61 , a mirror device 62 and a plurality of amplifiers 63 .

FIG. 5 is a block diagram showing the configuration of the optical sensor 61, mirror device 62, and amplifier 63 of the illumination device 1. FIG.

The optical sensor 61 detects part of the light emitted from the phosphor 4a as detection light L3, and outputs a detection signal s0. The optical sensor 61 is, for example, a photodetector element such as a photodiode, and outputs a detection signal s0 corresponding to the light amount of the received detection light L3.

As shown in FIG. 5, the optical sensor 61 is arranged on the side of the phosphor 4a and receives light emitted in a direction different from the emission direction of the illumination light L2. For example, the detection light L3 is light leaked in a direction perpendicular to the incident direction when the light is input to the phosphor 4a. An optical filter or the like that attenuates light in a wavelength band other than the wavelength band of the detection light L3 may be arranged on the optical path of the detection light L3 from the phosphor 4a to the optical sensor 61. FIG. The optical sensor 61 outputs a detection signal s0 to the mirror device 62 according to the light amount of the detection light L3.

The mirror device 62 outputs a plurality of output signals s1, s2 and s3 based on the detection signal s0 output from the optical sensor 61. Mirror device 62 is a current mirror circuit that uses active elements to replicate the current. The mirror device 62 outputs a plurality of output signals s1 to s3 having the same current value as the detection signal s0. In the example shown in FIG. 5, one detection signal s0 is input to the mirror device 62, and the mirror device 62 outputs three output signals s1 to s3.

The amplifier 63 is a circuit that amplifies the output signals s1 to s3 output by the mirror device 62. In this embodiment, the amplifier 63 has a current amplifier, a resistor, and the like. The amplified signal that is received is a voltage signal, and the larger the light amount of the detection light L3, the larger the value of the photocurrent and the higher the voltage value of the amplified signal. In the example shown in FIG. 5, three

amplifiers

63a, 63b and 63c are shown as the amplifier 63. In FIG.

Each of the plurality of amplifiers 63a-63c has a different gain. A plurality of amplifiers 63a-63c amplify the plurality of output signals s1-s3 with different gains and output a plurality of amplified signals sa, sb and sc. A first amplifier 63a of the plurality of amplifiers 63 has a first gain, a second amplifier 63b has a second gain lower than the first gain, and a third amplifier 63c has a second gain. has a third gain that is lower than the gain of . In other words, the second gain is higher than the third gain and the first gain is higher than the second gain.

FIG. 6 is a diagram showing the relationship between the light amount of the detection light L3 detected by the optical sensor 61 and the signal levels of the amplified signals sa to sc. The horizontal axis of FIG. 6 indicates the light amount of the detection light L3, and the vertical axis indicates the signal levels of the amplified signals sa to sc. The unit of signal level is a voltage value.

As shown in FIG. 6, the signal level of the amplified signal sa linearly increases from 0 as the light amount of the detection light L3 increases from 0 (zero). Then, when the light intensity of the detection light L3 exceeds a predetermined light intensity, the signal level becomes constant at the saturation voltage value. The same is true for the amplified signals sb and sc.

For example, the first gain of the first amplifier 63a and the second gain of the second amplifier 63b are equal to the gain of the signal sb amplified by the second amplifier 63b when the signal sa amplified by the first amplifier 63a is saturated. is set to vary linearly. Further, the second gain of the second amplifier 63b and the third gain of the third amplifier 63c are equal to the signal sc amplified by the third amplifier 63c when the signal sb amplified by the second amplifier 63b is saturated. is set to vary linearly.

Further, each gain of the plurality of amplifiers 63 is set when the signal level of the amplified signals sa to sc is equal to or lower than a first threshold Vth1, which is a predetermined threshold, so that the amplified signals sa to sc are not too far apart from each other in the horizontal axis direction. , it is set so that at least two amplified signals exist with respect to a predetermined light quantity x1 of the detection light L3. For example, in FIG. 6, the first gain and the second gain are set so that the amplified signals sa and sb exist with respect to the light amount x1 of the predetermined detection light L3. The first threshold value Vth1 is a value set from a signal level within a range in which the amplified signals sa to sc linearly change with respect to the light amount of the detection light L3. That is, the first threshold Vth1 is set to a value smaller than the saturation voltage value shown in FIG.

The gains of the plurality of amplifiers 63 are set when the signal levels of the amplified signals sa to sc are equal to or lower than the first threshold Vth1 and equal to or higher than the second threshold Vth2, which is smaller than the first threshold Vth1. , that is, when the signal level is within a predetermined range, at least two amplified signals are present for a predetermined light amount of the detection light L3.

The detection signal s0 output from the optical sensor 61 in this manner is duplicated by the mirror device 62 into a plurality of output signals s1 to s3, and is converted into a plurality of amplified signals sa to sc with different magnifications by the amplifier 63. output to

[Abnormality determination unit]
The abnormality determination unit 56 determines whether or not the lighting device 1 is abnormal. The abnormality determination unit 56 monitors the amplified signals sa to sc output from the detection circuit 60 and determines whether or not at least one of the phosphor 4a and the excitation source 6 is abnormal. In the example shown in FIG. 5, a plurality of amplified signals sa to sc generated by a plurality of amplifiers 63a to 63c are constantly output to the abnormality determining section 56. In the example shown in FIG. Therefore, there is no need to switch the gain of the amplifier circuit as in the prior art.

The abnormality determining unit 56 of the present embodiment selects the amplified signal having the maximum signal level among the amplified signals sa to sc whose signal level is equal to or lower than the first threshold value Vth1 with respect to the light amount of the detection light L3. The presence or absence of an abnormality is determined based on. In the example shown in FIG. 6, the abnormality determination unit 56 selects the amplified signal sa having the maximum signal level with respect to the light amount x1 of the detected light L3, and determines whether there is an abnormality based on this amplified signal sa.

The abnormality determination unit 56 uses the amplified signal when the light in the wavelength band of the excitation light L1 as the detection light L3, and the light in the wavelength band of the fluorescence obtained by wavelength-converting the excitation light L1 with the phosphor 4a as the detection light L3. The presence or absence of an abnormality may be determined based on the signal level ratio of the amplified signal in each case. For example, when the amplified signal when the excitation light L1 is the detection light L3 is the denominator, and the amplified signal when the fluorescence is the detection light L3 is the numerator, the abnormality determination unit 56 determines the signal levels of the two amplified signals. If the ratio is smaller than a predetermined ratio range, it may be determined that the phosphor 4a is abnormal. Further, the abnormality determination unit 56 may determine that the excitation source 6 has an abnormality when the ratio of the signal levels of the two amplified signals is greater than a predetermined range. Using the excitation light L1 as the detection light L3 is realized, for example, by arranging an optical filter that transmits the wavelength of the excitation light L1 on the optical path between the phosphor 4a and the optical sensor 61. FIG. Fluorescence can be used as the detection light L3, for example, by arranging an optical filter that transmits the wavelength of the fluorescence on the optical path between the phosphor 4a and the optical sensor 61. FIG.

In addition, the abnormality determination unit 56 may determine the presence or absence of an abnormality based on whether the rate of decrease in the signal level of the selected amplified signal is greater than a predetermined threshold. For example, the abnormality determination unit 56 compares the signal level calculated based on the current detected light L3 and the signal level acquired immediately before that, and if the rate of decrease in the signal level is equal to or less than a predetermined threshold, , the excitation source 6 or the phosphor 4a may be determined to be abnormal. A predetermined threshold as the rate of decrease in the signal level of the amplified signal may be, for example, about 50%.

[Output control circuit]
The output control circuit 58 controls the current supplied to each light emitting element of the excitation source 6 by controlling the power supply circuit 51 and the light source switching section 54 . More specifically, the output control circuit 58 controls the power supply circuit 51 to adjust the driving current I1. That is, the output control circuit 58 has a dimming function that adjusts the light amount of the excitation light L1 by making the drive current I1 variable.

Further, the output control circuit 58 according to the present embodiment, when the abnormality determination unit 56 determines that an abnormality has occurred in the lighting device 1, more specifically, detects an abnormality in the phosphor 4a or the excitation source 6. If it is determined that the current is supplied to the excitation source 6, the current supply is stopped.

As described above, the output control circuit 58 and the abnormality determination section 56 are configured by the controller 5c. The controller 5c includes, for example, a control IC (Integrated Circuit), a computer system, and the like. A computer system has a processor that operates according to a program as a main hardware configuration. The type of the processor is not limited as long as it can implement each function of the controller 5c by executing a program.

Thus, the illumination device 1 according to the present embodiment includes the excitation source 6 that emits the excitation light L1, the phosphor 4a that receives the excitation light L1 and emits fluorescence, and at least one of the excitation light L1 and the fluorescence. light as detection light L3, a photosensor 61 that outputs a detection signal s0 based on the detection light L3, a mirror device 62 that outputs a plurality of output signals s1 to s3 based on the detection signal s0, a plurality of output signals s1 to s3 with different gains and output a plurality of amplified signals sa to sc; and an abnormality determination unit 56 that determines the presence or absence of an abnormality based on the amplified signal having the maximum signal level among the amplified signals whose level is equal to or lower than the predetermined threshold value Vth1.

According to this configuration, it is possible to determine the presence or absence of an abnormality by using an amplified signal suitable for determining the presence or absence of an abnormality among a plurality of amplified signals amplified with different gains. Therefore, it becomes unnecessary to switch the gain of the amplifier, and it is possible to suppress the occurrence of a period in which an abnormality of the lighting device 1 cannot be detected due to the switching of the gain. As a result, it is possible to timely determine whether or not there is an abnormality in the lighting device 1 .

[2. Operation of lighting device]
The operation of the illumination device 1 will be described.

First, when the AC power of the input power supply P1 is applied to the lighting device 1, the output control circuit 58 controls the power supply circuit 51 to supply the drive current I1 to the excitation source 6. A plurality of light emitting elements 6a to 6d of excitation source 6 emit blue excitation light L1 by drive current I1. The excitation light L1 passes through the optical member 7 and the light guide member 3 and reaches the phosphor 4a. The phosphor 4a generates white light (wavelength-converted light) from the blue excitation light L1. The phosphor 4a irradiates the illumination space with most of the white light as the illumination light L2. Part of the white light reaches the optical sensor 61 of the detection circuit 60 as detection light L3.

The detection light L3 is the same white light as the illumination light L2 that is actually applied to the illumination space, and contains information about the light amount of the illumination light L2. That is, the greater the light intensity of the illumination light L2, the greater the light intensity of the detection light L3. Therefore, the larger the light intensity of the illumination light L2, the higher the voltage value of the amplified signal sa, and the smaller the light intensity of the illumination light L2, the lower the voltage value of the amplified signal sa. That is, information on the amount of light of the illumination light L2 is fed back to the lighting device 5 as the detected light L3.

The output control circuit 58 monitors the light intensity of the excitation light L1 emitted by the excitation source 6 based on the voltage value of the amplified signal sa. The output control circuit 58 controls the power supply circuit 51 so that the voltage value of the amplified signal sa matches the target voltage value, thereby performing feedback control to match the drive current I1 to the target current. 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 58 can perform dimming control by making the target voltage value variable.

Further, in the present embodiment, a plurality of output signals s1 to s3 are generated based on the detection signal s0 output from the optical sensor 61 by receiving the detection light L3. Then, the plurality of output signals s1 to s3 are amplified with different gains to generate a plurality of amplified signals sa to sc. Then, the presence or absence of an abnormality is determined based on the amplified signal having the maximum signal level among the amplified signals sa to sc whose signal level is equal to or lower than a predetermined threshold value Vth1 with respect to the light amount of the detection light L3.

According to this configuration, the presence or absence of an abnormality can be determined by using an amplified signal suitable for determining the presence or absence of an abnormality from among the plurality of amplified signals sa to sc amplified with different gains. Therefore, it becomes unnecessary to switch the gain of the amplifier, and it is possible to suppress the occurrence of a period in which an abnormality of the lighting device 1 cannot be detected due to the switching of the gain. As a result, it is possible to timely determine whether or not there is an abnormality in the lighting device 1 .

[3. Endoscope device equipped with illumination device]
An endoscope apparatus including the lighting device 1 described above will be described.

FIG. 7 is a schematic diagram showing the configuration of an endoscope device 90 including the illumination device 1 of the embodiment.

The endoscope device 90 includes an illumination device 1 and an observation device 91. The illumination device 1 has a configuration similar to that of the above embodiment.

The observation device 91 is a device for observing the subject. The observation device 91 includes an objective optical system 92 that is exposed near the phosphor 4a, a CCD (Charge Coupled Device) 93 that is an imaging element provided at an image forming position of the objective optical system 92, and a light source device. 2 and a signal cable 95 connecting the CCD 93 and the video signal processing circuit 94 . In the observation device 91 , an observation image of the subject formed by the objective optical system 92 is converted into an electric signal by the CCD 93 and transmitted as an image signal by the signal cable 95 . The transmitted image signal is converted into a video signal by the video signal processing circuit 94 and displayed as a video on a monitor (not shown) connected to the observation device 91 . Also in this endoscope device 90, the same effects as those of the illumination device 1 can be obtained.

Although FIG. 7 shows an example in which the excitation light L1 is guided to the vicinity of the tip of the endoscope device 90 by the light guide member 3 and then converted into the illumination light L2, the present invention is not limited to this. For example, the illumination light L2 converted from the excitation light L1 can be guided to the distal end of the endoscope device 90 by the light guide member 3 . By adopting a structure for guiding the illumination light L2, there is no need to install a sensor or the like near the distal end of the endoscope device 90, and the diameter of the endoscope can be reduced.

[4. effects, etc.]
As described above, the illumination device 1 according to the present embodiment includes the excitation source 6 that emits the excitation light L1, the phosphor 4a that receives the excitation light L1 and emits fluorescence, and at least one of the excitation light L1 and the fluorescence. A photosensor 61 that outputs a detection signal s0 based on the detection light L3, a mirror device 62 that outputs a plurality of output signals s1 to s3 based on the detection signal s0, and a plurality of output signals. A plurality of amplifiers 63 that amplify s1 to s3 with different gains and output a plurality of amplified signals sa to sc, and among the plurality of amplified signals sa to sc, a plurality of amplified signals sa to sc with respect to the light amount of the detection light L3. and an abnormality determination unit 56 that determines whether there is an abnormality based on the amplified signal having the maximum signal level among the amplified signals having the signal level equal to or lower than the predetermined threshold value Vth1.

Further, the abnormality determination unit 56 may determine whether or not at least one of the excitation source 6 and the phosphor 4a is abnormal based on the amplified signal with the maximum signal level.

According to this configuration, it is possible to suppress the occurrence of a period during which an abnormality in the excitation source 6 or the phosphor 4a cannot be detected due to switching of the gain of the amplifier. As a result, it is possible to timely determine whether or not there is an abnormality in the lighting device 1 .

Further, the abnormality determination unit 56 may determine the presence or absence of an abnormality based on the signal level ratio of the amplified signal when the excitation light L1 is used as the detection light L3 and the amplified signal when fluorescence is used as the detection light L3. good.

According to this configuration, it is possible to timely determine whether or not there is an abnormality in both the excitation source 6 and the phosphor 4a.

Also, the mirror device 62 is a current mirror circuit, and may output a plurality of output signals s1 to s3 having the same current value as the detection signal s0.

According to this configuration, the presence or absence of an abnormality can be determined using a plurality of output signals s1 to s3. Therefore, it becomes unnecessary to switch the gain of the amplifier, and it is possible to suppress the occurrence of a period in which an abnormality of the lighting device 1 cannot be detected due to the switching of the gain. As a result, it is possible to timely determine whether or not there is an abnormality in the lighting device 1 .

A first amplifier 63a of the plurality of amplifiers 63 has a first gain, a second amplifier 63b has a second gain lower than the first gain, and the first gain and the second amplifier 63b have a second gain lower than the first gain. A gain of 2 may be set so that when the signal sa amplified by the first amplifier 63a is saturated, the signal sb amplified by the second amplifier 63b changes linearly.

According to this configuration, the abnormality determination unit 56 can acquire a plurality of amplified signals without interruption, and among the acquired amplified signals, an amplified signal suitable for reading for determining the presence or absence of an abnormality. can be selected to determine whether there is an abnormality. As a result, it is possible to timely determine whether or not there is an abnormality in the lighting device 1 .

Also, the predetermined threshold Vth1 may be set from a signal level within a range in which each of the plurality of amplified signals sa to sc linearly changes with respect to the light amount of the detection light L3.

According to this configuration, the amplified signal can be acquired with high accuracy, and the amplified signal suitable for reading for determining the presence or absence of an abnormality is selected from among the plurality of acquired amplified signals, and the determination of the presence or absence of an abnormality is performed. It can be carried out. As a result, it is possible to timely determine whether or not there is an abnormality in the lighting device 1 .

Also, the optical sensor 61 may detect light emitted in a direction different from that of the illumination light L2 emitted from the phosphor 4a as the detection light L3.

According to this, the detection light L3 can be easily obtained with little attenuation. This makes it possible to easily determine whether or not there is an abnormality in the lighting device 1 .

Also, the excitation source 6 may be a laser element.

According to this, it is possible to determine whether or not there is an abnormality in the illumination device 1 by using the light emitted from the laser element as the excitation light L1.

Also, the endoscope apparatus 90 according to the present embodiment may include the illumination device 1 described above and an observation device 91 for observing the subject.

According to this, it is possible to provide the endoscope device 90 having the illumination device 1 capable of timely determining whether or not there is an abnormality.

(Other embodiments)
As described above, the illumination device and the like according to the multiple aspects of the present disclosure have been described based on the embodiments, but the present disclosure is not limited to these embodiments. As long as it does not deviate from the spirit of the present disclosure, various modifications that can be conceived by those skilled in the art are applied to the present embodiment, and forms constructed by combining the components of different embodiments are also included within the scope of the present disclosure. may

For example, in the embodiment, the light guide member 3 is used as the optical system. is not limited to For example, optical elements such as mirrors and lenses may be used as the optical system.

1 illumination device 4a phosphor 6 excitation source 56 abnormality determination unit 61 optical sensor 62

mirror devices

63, 63a, 63b, 63c amplifier 90 endoscope device 91 observation device L1 excitation light L2 illumination light L3 detection light s0 detection signals s1 and s2 , s3 output signals sa, sb, sc amplified signals Vth1, Vth2 threshold

Claims

an excitation source that emits excitation light;
a phosphor that receives the excitation light and emits fluorescence;
an optical sensor that uses at least one of the excitation light and the fluorescence as detection light and outputs a detection signal based on the detection light;
a mirror device that outputs a plurality of output signals based on the detection signal;
a plurality of amplifiers for amplifying the plurality of output signals with different gains and outputting a plurality of amplified signals;
Among the plurality of amplified signals, the presence or absence of an abnormality is determined based on the amplified signal having the maximum signal level among the amplified signals having a signal level equal to or lower than a predetermined threshold with respect to the light amount of the detected light. an abnormality determination unit that determines;
A lighting device.
The lighting device according to claim 1, wherein the abnormality determination section determines whether or not at least one of the excitation source and the phosphor is abnormal based on the amplified signal having the maximum signal level.
2. The abnormality determination unit determines whether there is an abnormality based on a signal level ratio of the amplified signal when the excitation light is used as the detection light and the amplified signal when the fluorescence is used as the detection light. The lighting device according to
The lighting device according to any one of claims 1 to 3, wherein the mirror device is a current mirror circuit and outputs the plurality of output signals having the same current value as the detection signal.
a first amplifier of the plurality of amplifiers having a first gain and a second amplifier having a second gain lower than the first gain;
The first gain and the second gain are set so that the signal amplified by the second amplifier changes linearly when the signal amplified by the first amplifier is saturated. The lighting device according to any one of .
The lighting device according to any one of claims 1 to 5, wherein the predetermined threshold is set from the signal level in a range in which each of the plurality of amplified signals linearly changes with respect to the light amount of the detected light. .
The illumination device according to any one of claims 1 to 6, wherein the optical sensor detects light emitted in a direction different from that of the illumination light emitted from the phosphor as the detection light.
The illumination device according to any one of claims 1 to 7, wherein the excitation source is a laser element.
a lighting device according to claim 8;
an observation device for observing a subject;
An endoscope device comprising: