JP2008289711A - Endoscope apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope apparatus capable of accurately detecting abnormality of illumination light emitted by illuminating means without being influenced by entering external light. <P>SOLUTION: The endoscope apparatus 1 includes: the illuminating means 10 for emitting illumination light; photodetecting means 30 disposed so as to detect light quantity of the illumination light; and a control section 40 for switching the illuminating means between an illumination state for emitting the illumination light and a non-illumination state for not emitting the light. The control section 40 detects the light quantity in the illumination state and the non-illumination state by the photodetecting means 30, and monitors a difference in light quantity between the illumination state and the non-illumination state. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an endoscope apparatus that is inserted into a subject to illuminate and observe the inside.

  In recent years, laser light has been used for various purposes such as processing, measurement, and illumination of a subject. For example, there is a laser knife that irradiates a predetermined portion with laser light with a predetermined amount of light for the purpose of excising a predetermined portion of a patient. Such a laser knife has a light detection means for detecting the amount of the irradiated laser beam so that the laser beam is not irradiated with a high output when the configuration for outputting the laser beam fails. Has been proposed (see, for example, Patent Document 1). More specifically, the light detection means of the laser knife detects the amount of reflected laser light that has been reflected from the light exit surface and returned from the laser light emitted from the light source and incident on the light guide that is the light transmission member. By doing so, it is supposed that the amount of the laser beam to be output can be detected.

On the other hand, as for using laser light for illumination, for example, laser light is used as excitation light, and the fluorescent member is excited by being guided by a light guide and irradiated on the fluorescent member. There is an illumination device that emits illumination light. Such an illuminating device is small and power-saving, and can obtain high-output illumination light, and thus is also used for an endoscope device or the like (see, for example, Patent Document 2).
Japanese Patent Publication No.3-3174 JP 2006-288535 A

  However, in the endoscope apparatus of Patent Document 2, when any configuration of the illumination device that uses the laser light as excitation light fails, it becomes impossible to irradiate white light with a desired light amount. There was a case. For example, when an abnormality occurs in the fluorescent member, the laser beam may pass through the fluorescent member and be irradiated to the outside with a large amount of light, which may damage the subject. For this reason, it is necessary to detect the amount of illumination light emitted from the fluorescent member and to monitor the presence or absence of abnormality. However, in the case where the laser light is detected in place of the illumination light by the method as described in Patent Document 1, or the illumination light irradiated from the fluorescent member is directly detected, the external light entering from the outside Will also be detected. For this reason, there has been a problem that the abnormality of the illumination light cannot be accurately detected because it is obstructed by the external light. In particular, when the amount of laser light is increased and illuminated, it affects the subject, so it is necessary to detect at a stage where the change in the amount of laser light is small. If the amount of light is large, there is a possibility that the abnormality cannot be detected until the amount of laser light increases and the subject is affected.

  The present invention has been made in view of the above-described circumstances, and can accurately detect an abnormality of illumination light irradiated by the illumination means without being affected by incident external light. An endoscope apparatus is provided.

In order to solve the above problems, the present invention proposes the following means.
The present invention is an endoscope apparatus that has an insertion portion that is inserted into a subject, and that observes the inside of the subject by observation means provided on a distal end side of the insertion portion, and that includes illumination light. Illuminating means for irradiating, a light detecting means arranged to detect the amount of illumination light, and a controller for switching the illuminating means between an illumination state in which the illumination light is illuminated and a non-illuminated state in which the illumination light is not illuminated. The control unit detects the light amount by the light detection means in each of the illumination state and the non-illumination state, and monitors a difference between the light amount in the illumination state and the light amount in the non-illumination state. It is characterized by that.

  According to the endoscope apparatus according to the present invention, the inside of the subject can be observed by the observation unit using the reflected light reflected from the illumination light irradiated from the illumination unit. Here, the control unit switches between the illumination state in which the illumination unit irradiates the illumination light and the non-illumination state in which the illumination unit does not irradiate as described above, detects the light amount by the light detection unit in each state, and monitors the difference between them. . Here, in the illumination state, the light detection unit detects a light amount obtained by synthesizing the illumination light irradiated by the illumination unit and the external light incident from the outside. On the other hand, in the non-illuminated state, since the illumination light is not irradiated by the illumination means, only the amount of external light is detected. For this reason, the control part can detect the light quantity of illumination light correctly by the said difference.

  In the endoscope apparatus, the illumination unit may include a light source unit that emits excitation light according to a supplied current, and a fluorescent member that is excited by the excitation light and emits the illumination light. More preferred.

  According to the endoscope apparatus according to the present invention, when the excitation light emitted from the light source unit is irradiated onto the fluorescent member, the fluorescent member is excited and emits illumination light having a light amount corresponding to the light amount of the excitation light. It will be injected outside.

  In the endoscope apparatus, the control unit switches from the illumination state to the non-illumination state at a timing not affected by the observation by the observation unit, and detects the light amount in the non-illumination state. Is more preferable.

  According to the endoscope apparatus according to the present invention, the control unit performs the detection between the illumination state and the non-illumination state so that the light amount detection by the light detection unit in the non-illumination state is performed at a timing not affected by the observation by the observation unit. By switching between, the object can be suitably observed by the observation means while accurately detecting the amount of illumination light.

  Furthermore, in the above endoscope apparatus, the observation unit is provided on a distal end side of the insertion portion, and photoelectrically converts the received image and outputs it as an image signal, and the output from the imaging element A video signal processing circuit that generates and outputs a video signal from the image signal by a method having a blanking period, and the control unit detects the light amount in the non-illuminated state during the blanking period. Is more preferable.

  According to the endoscope apparatus according to the present invention, the image received by the image sensor is photoelectrically converted and output as an image signal, and the video signal is output from the image signal by the video signal processing circuit, whereby the subject is converted into an image. Can be observed. Here, the control unit switches from the illumination state to the non-illumination state and detects the amount of light during the blanking period of the observation unit, so that the image obtained by the observation unit is affected by the non-illumination state. The subject can always be observed by the image in the illumination state.

  In the endoscope apparatus, the control unit may illuminate the subject when a difference between the light amount in the illumination state and the light amount in the non-illumination state exceeds a preset threshold value. It is more preferable to stop the light irradiation.

  According to the endoscope apparatus according to the present invention, when the difference between the light amount in the illumination state and the light amount in the non-illumination state exceeds the threshold, the illumination light is abnormal by stopping the irradiation of the illumination light to the subject. It is possible to automatically prevent the subject from being irradiated in such a state.

  The endoscope apparatus includes a light source driving unit that supplies current to the light source unit, and the control unit switches between supply and non-supply of current by the light source driving unit, so that the illumination state and the light source unit are switched. It is more preferable to switch to the non-illuminated state.

  According to the endoscope apparatus according to the present invention, the control unit automatically switches between the illumination state and the non-illumination state by switching between the supply and non-supply of the current to the light source unit. Thus, the amount of light entering the light detecting means can be detected and the difference can be monitored.

  In the endoscope apparatus, the excitation light emitted from the light source unit or shielding means for shielding the illumination light emitted from the fluorescent member, and the excitation light or the illumination light by the shielding means Switching means for switching between shielding and non-shielding, and the control unit drives the switching means to switch between the illumination state and the non-illumination state by switching between shielding and non-shielding by the shielding means. Is more preferable.

  According to the endoscope apparatus according to the present invention, the switching unit is driven by the control unit, and switching between the illumination state and the non-illumination state is performed automatically by switching between shielding and non-shielding by the shielding unit, In response to this, the amount of light entering the light detecting means can be detected, and the difference can be monitored.

In the above endoscope apparatus, it is more preferable to include an external light shielding unit that shields light incident on the light detection unit from the outside.
According to the endoscope apparatus according to the present invention, the light incident on the light detection means from the outside is shielded by the external light shielding means, thereby minimizing the light other than the illumination light entering the light detection means. The amount of illumination light can be detected more accurately based on the difference.

Further, in the above endoscope apparatus, the light detection means detects a return light that is part of the illumination light emitted from the illumination means, and guides the return light to the light sensor. It is more preferable to have an optical transmission member for detection.
According to the endoscope apparatus according to the present invention, the light detection means guides the return light, which is part of the illumination light, by the detection light transmission member, and detects the return light by the optical sensor, thereby illuminating. The amount of illumination light emitted from the means can be accurately detected.

  According to the endoscope apparatus of the present invention, the illumination that is irradiated by the illuminating means without being affected by the incident external light is detected by switching between the illumination state and the non-illumination state by the control unit. Optical anomalies can be detected accurately.

(First embodiment)
A first embodiment according to the present invention will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1, an endoscope apparatus 1 according to the present embodiment performs inspection and diagnosis work on a target part inside a subject such as a pipe, and is an elongated insertion inserted into the subject. Unit 2, an operation unit 3 provided at the proximal end of the insertion unit 2, and an apparatus main body unit 4 connected to the operation unit 3 by a universal cord 3 a and having a monitor 4 a. The insertion portion 2 is a flexible type that is flexible, and in order from the distal end, a hard distal end portion 2a, a bending portion 2b that can be bent by an operation by the operation portion 3, and a flexibility that can be bent according to the shape of the subject. Flexible tube portion 2c. The operation portion 3 is provided with a bending knob 3b, and the bending portion 2b can be bent in a predetermined direction by operating the bending knob 3b.

  FIG. 2 shows details of the internal configuration of the endoscope apparatus 1. As shown in FIG. 2, the insertion unit 2 and the apparatus main body unit 4 include an observation unit 6 for observing a target portion of a subject located on the distal end side of the insertion unit 2, and an illumination unit 10 for illuminating the target portion. There are provided a light detection means 30 for detecting the amount of light entering from the distal end of the insertion section 2 and a control section 40 for switching the illumination by the illumination means 10 and monitoring the illumination light. The apparatus main body 4 is also provided with a CPU for controlling the entire apparatus and an operation section for performing various operations and settings, but is omitted. The observation means 6 includes an objective optical system 6a provided at the distal end portion 2a of the insertion section 2, a CCD (Charge Coupled Device) 6b that is an image pickup element provided at an image forming position of the objective optical system 6a, and an apparatus main body. It includes an NTSC encoder 6c that is a video signal processing circuit built in the unit 4, and a signal cable 6d that is disposed in the insertion unit 2 and connects the CCD 6b and the NTSC encoder 6c. Then, by driving the CCD 6b, the observation image formed by the objective optical system 6a is converted into an electrical signal by the CCD 6b and output as an image signal. The output image signal is input to the NTSC encoder 6c via the signal cable 6d. Thus, a video signal such as a composite video signal is generated by the NTSC encoder 6c and output to the monitor 4a, so that the target region of the subject can be displayed as an image on the monitor 4a. The NTSC encoder 6c outputs a video signal to the monitor 4a and correspondingly outputs a video synchronization signal to a microcomputer 43 (to be described later) of the control unit 40.

  The illuminating means 10 includes a laser diode 11 that is built in the apparatus main body 4 and emits laser light as excitation light, a light source driving unit 12 that supplies current to the laser diode 11, and an insertion unit 2. An illumination light guide 13 that is an illumination light transmission member disposed from the proximal end side to the distal end side, and a fluorescent member 14 provided in the insertion portion 2 are provided. The laser diode 11 can emit laser light having a specific wavelength with a light amount corresponding to the amount of current supplied. In the present embodiment, for example, blue laser light can be emitted. Further, the laser diode 11 is connected to the base end of the illumination light guide 13 via the condensing optical system 15, so that the laser light emitted from the laser diode 11 is condensed by the condensing optical system 15. Then, the light enters the proximal end of the illumination light guide 13 and is guided to the distal end of the illumination light guide 13, that is, the distal end side of the insertion portion 2. The fluorescent member 14 is connected to the tip of the illumination light guide 13, and the laser light guided by the illumination light guide 13 is irradiated to the fluorescent member 14. As a result, the fluorescent member 14 is excited to generate white light having a light amount corresponding to the light amount of the laser light, and this is emitted as illumination light. The emitted illumination light is irradiated to the distal end side via the illumination optical system 16 provided on the distal end side of the illumination light guide 13 to illuminate the target portion of the subject.

  The light source driving unit 12 also includes a power source 20 that supplies power to the laser diode 11, a regulator 21 that switches power supply from the power source 20 to the laser diode 11, and a constant current that supplies a constant current to the laser diode 11. Circuit 22. The constant current circuit 22 includes an operational amplifier 22a, a transistor 22b, and voltage dividing resistors 22c and 22d. A light source output adjustment circuit 17 is connected to the operational amplifier 22 a of the constant current circuit 22, and the light source driver 12 can adjust the amount of current supplied to the laser diode 11 under the control of the light source output adjustment circuit 17. It has become. Note that a switch circuit 17a is connected between the light source drive unit 12 and the light source output adjustment circuit 17, and the light source drive unit 12 can be switched on and off by switching the switch circuit 17a. Further, the light source driving unit 12 includes current abnormality detection means 23 that detects an abnormality in the current of the constant current circuit 22. The current abnormality detection means 23 detects a voltage value divided by the voltage dividing resistors 22c and 22d of the constant current circuit 22 and amplifies the voltage value output from the current detection voltage amplification circuit 23a. A comparison circuit 23c for comparing with a preset reference voltage 23b is provided. The comparison circuit 23 c is connected to a microcomputer 43 (described later) of the regulator 21 and the control unit 40. The reference voltage 23b is set to a magnitude that serves as a criterion for determining the abnormality of the constant current circuit 22, whereby the comparison circuit 23c stops the regulator 21 and stops the irradiation of the laser light from the laser diode 11. In addition, it is possible to output the determination of whether there is an abnormality in the constant current circuit 22 to the microcomputer 43 of the control unit 40.

  The light detection means 30 includes a detection light guide 31 that is a detection light transmission member disposed in the insertion portion 2 from the proximal end side to the distal end side, and a detection light guide in the device main body portion 4. And an RGB sensor 32 which is an optical sensor provided at the base end of the reference numeral 31. The tip of the detection light guide 31 is disposed so as to face a part of the illumination optical system 16 of the illumination means 10, and the illumination light that enters the illumination optical system 16 from the fluorescent member 14 and is internally reflected. It is possible to guide a part of the light as return light. In the illumination optical system 16, the outside optical surface 16 a exposed to the outside is shielded from external light entering the illumination optical system 16 in a range facing the detection light guide 31. An external light shielding plate 30a is provided. The RGB sensor 32 can detect the light guided by the light guide 31 for detection, and the first optical sensor 33a capable of detecting the red wavelength region in the illumination light, detects the green wavelength region. A second optical sensor 33b, a third optical sensor 33c capable of detecting a blue wavelength region, and amplification circuits 34a, 34b, 34c for amplifying detection signals output from the respective optical sensors; Have The first optical sensor 33a, the second optical sensor 33b, and the third optical sensor 33c detect, for example, a color filter that can transmit only the corresponding wavelength region and a light amount that has transmitted through the color filter. It consists of a photodiode that converts it into an electrical signal.

  The control unit 40 also detects an abnormality detection circuit 41 that monitors the state of the illumination light based on the detection result of the light detection unit 30, and from the light source driving unit 12 to the laser diode 11 based on a control signal from the abnormality detection circuit 41. A light source on / off control circuit 42 that switches between supply and non-supply of the current. The abnormality detection circuit 41 includes AD converters 41a, 41b, and 41c that AD-convert detection signals in the respective wavelength regions output from the RGB sensor 32 of the light detection means 30, and a microcomputer 43 that receives the AD-converted detection signals. And have. The light source on / off control circuit 42 includes a resistor 42a and a diode 42b. Based on a control signal from the microcomputer 43, the light source output adjustment circuit 17 to the constant current circuit 22 of the light source driver 12 is provided. It is possible to switch on and off the adjustment signal to the light source, thereby switching between supply and non-supply of current from the light source driving unit 12 to the laser diode 11, and illumination state in which illumination light is irradiated from the fluorescent member 14 It is possible to switch to a non-illuminated state that is not irradiated.

More specifically, the microcomputer 43 of the control unit 40 outputs a low-level voltage value to the light source on / off control circuit 42 as a control signal in the illumination state, thereby adjusting the light source output. An adjustment signal is output from the circuit 17 to the light source driving unit 12, and illumination light is emitted from the fluorescent member 14. On the other hand, the microcomputer 43 of the control unit 40 outputs a high-level voltage value as a control signal to the light source on / off control circuit 42 in the non-illuminated state. The output of the adjustment signal to the light source driving unit 12 is stopped, and the irradiation of the illumination light from the fluorescent member 14 is stopped. The microcomputer 43 of the control unit 40 is normally in an illumination state and is not in a blanking period, which is a timing that does not affect the observation by the observation means 6 based on the video synchronization signal input from the NTSC encoder 6c. The illumination state is monitored, and the detection result from the RGB sensor 32 is compared between the illumination state and the non-illumination state to monitor the illumination light state.
Hereinafter, the operation of the endoscope apparatus 1 of the present embodiment and the details of the illumination light monitoring by the control unit 40 will be described.

  As shown in FIG. 2, when a power switch (not shown) of the endoscope apparatus 1 is turned on, the light source output adjustment circuit 17 adjusts the light source drive unit 12 according to the setting by the light amount adjustment knob of the operation panel (not shown). A signal is output. For this reason, a current having a magnitude corresponding to the adjustment signal is supplied from the light source driving unit 12 to the laser diode 11. At this time, if an abnormality is found in the current value supplied to the laser diode 11 by the current abnormality detecting means 23, the supply of current to the laser diode 11 is forcibly stopped by stopping the regulator 21. Be made.

  In addition, when the amount of current supplied to the laser diode 11 is normal, the laser diode 11 emits a laser beam having a light amount corresponding to the amount of current supplied, and the fluorescent member 14 is excited to emit illumination light. The illumination light illuminates the outside through the illumination optical system 16. Then, the target portion of the subject can be observed by the observation means 6 using the external light including the reflected light reflected by the target portion of the subject. At this time, the illumination light from the fluorescent member 14 incident on the illumination optical system 16 and reflected from the inner surface and a part of external light from the outside are input to the tip of the detection light guide 31 of the light detection means 30. Will be. In addition, since the external light shielding plate 30a is provided in a range facing the detection light guide 31 in the outer surface 16a of the illumination optical system 16, the external light passes through the illumination optical system 16 and is directly detected. The light guide 31 does not enter the light guide 31, and only the external light that has entered from the other range of the illumination optical system 16 and reflected from the inner surface enters the light guide 31 for detection. Then, these input lights are guided to the base end side by the light guide 31 for detection, and the light quantity is detected by the RGB sensor 32. In the RGB sensor 32, the light amount of the input light is separated into each wavelength region by the first optical sensor 33a, the second optical sensor 33b, and the third optical sensor 33c and detected as a voltage value. Output to the microcomputer 43. At this time, in a normal state, a low level voltage value control signal is continuously output from the microcomputer 43 of the control unit 40 to the light source on / off control circuit 42, so that the light source output adjustment circuit 17 outputs the light source drive unit 12. The adjustment signal is output and current is continuously supplied from the light source driving unit 12 to the laser diode 11. That is, an illumination state in which illumination light is irradiated to the outside from the fluorescent member 14 of the illumination unit 10 is maintained, and an image of the subject can be suitably acquired by the observation unit 6 under illumination by the illumination light.

  On the other hand, the microcomputer 43 of the control unit 40 controls the high-level voltage value every time the video acquired by the observation means 6 enters the vertical blanking period, based on the video synchronization signal input from the NTSC encoder 6c. Output a signal. For this reason, while the video is in the vertical blanking period, the output of the adjustment signal from the light source output adjustment circuit 17 to the light source driving unit 12 is stopped, and the current from the light source driving unit 12 to the laser diode 11 is not supplied. Switch to non-supply. That is, when the laser diode 11 does not emit light, the illumination member 10 is in a non-illuminated state where illumination light is not emitted from the fluorescent member 14 to the outside. Here, by setting the non-illuminated state only during the vertical blanking period, even if the input to the CCD 6b of the observation means 6 is changed, there is no influence on the acquired image.

  Even in this non-illuminated state, the microcomputer 43 of the control unit 40 acquires the detection result of the RGB sensor 32 of the light detection means 30, and calculates the difference between the light amount in each wavelength region and the detection result in the immediately previous illumination state. Calculate. Then, the calculated difference in each wavelength region is compared with a threshold value set in advance corresponding to each wavelength region. The threshold value includes a lower limit value and an upper limit value, and either one or both of them may be set. Here, in the non-illuminated state, since the illumination light is not irradiated from the fluorescent member 14, only the external light is incident on the detection light guide 31 of the light detection means 30 and detected by the RGB sensor 32. is there. For this reason, by calculating the difference between the amount of light detected by the RGB sensor 32 in the illumination state and the amount of light detected in the non-illumination state by the microcomputer 43 of the control unit 40, the illumination optical system 16 reflects the inner surface. Thus, the amount of illumination light entering the detection light guide 31 is obtained by subtracting the change component of the amount of light (detection voltage) due to external light, and the amount of illumination light is compared by comparing the difference with the threshold value. It is possible to accurately evaluate whether or not is abnormal.

  More specifically, the microcomputer 43 of the control unit 40 obtains a difference for each detection result of the first optical sensor 33a, the second optical sensor 33b, and the third optical sensor 33c of the RGB sensor 32, and corresponds to each of the detection results. Compare with threshold. For example, if the difference between all detection results of the first optical sensor 33a, the second optical sensor 33b, and the third optical sensor 33c is less than the corresponding lower limit value, the illumination light guide 13 is damaged. Therefore, it is considered that a part of the laser light from the laser diode 11 leaks from the illumination light guide 13 and is not irradiated to the fluorescent member 14. Further, when the detection results of the first optical sensor 33a and the second optical sensor 33b are respectively lower than the corresponding lower limit value and the detection result of the third optical sensor 33c exceeds the corresponding upper limit value, that is, blue Is detected as a large amount of light, it is considered that the fluorescent member 14 is broken and the blue laser light from the laser diode 11 is directly irradiated to the outside. Here, since the light quantity change component due to external light can be subtracted as described above and the amount of illumination light can be accurately evaluated, even if a large amount of external light is emitted from the subject side, A slight change in the illumination light can be accurately detected. In particular, the external light shielding plate 30a regulates the amount of illumination light more accurately by restricting external light from directly passing through the illumination optical system 16 and entering the detection light guide 31. can do. If it is recognized that the amount of illumination light is in an abnormal state, the microcomputer 43 of the control unit 40 continues to output a high-level control signal to the light source on / off control circuit 42 thereafter. Therefore, it is possible to prevent the illumination light from being irradiated to the outside in an abnormal state.

  As described above, in the endoscope apparatus 1 according to the present embodiment, the microcomputer 43 of the control unit 40 is detected by switching between the illumination state and the non-illumination state, thereby being influenced by the incident external light. Without abnormality, it is possible to accurately detect an abnormality in the illumination light emitted from the fluorescent member 14 by the laser light. Based on the detection result, when the illumination light is abnormal, illumination of the illumination light to the subject can be automatically stopped to prevent the subject from being affected by the illumination light. In the endoscope apparatus 1 of the present embodiment, the amount of light in the non-illuminated state is detected during the vertical blanking period of the image acquired by the observation unit 6, thereby affecting the observation by the observation unit 6. The illumination state and the non-illumination state can be switched at a timing when the light is not received to detect an abnormality of the illumination light, and the subject can be preferably observed. Note that the detection of the amount of light in the non-illuminated state is performed every vertical blanking period, but is not limited thereto. For example, the non-illumination state is set at a rate of once for a plurality of vertical blanking periods to detect the light amount, and based on this, the difference in the light amount between the illumination state and the non-illumination state is monitored. Also good.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. FIG. 3 shows a second embodiment of the present invention. In this embodiment, members that are the same as those used in the above-described embodiment are assigned the same reference numerals, and descriptions thereof are omitted.

  As shown in FIG. 3, the endoscope apparatus 50 of this embodiment is provided between the laser diode 11 and the condensing optical system 15 and can shield the laser light from the laser diode 11. And a drive unit 52 that is a switching unit that switches between shielding and non-shielding of the laser beam by moving the shielding member 51 forward and backward. The drive unit 52 is connected to the microcomputer 43 of the control unit 40 and can be driven based on a shielding control signal output from the microcomputer 43.

  In the case of the present embodiment, in the illumination state, the microcomputer 43 of the control unit 40 causes the laser light from the laser diode 11 to reach the condensing optical system 15 by setting the shielding member 51 in the retracted state. It is possible to irradiate the fluorescent member 14 through the illumination light guide 13 and thereby generate illumination light for illumination. On the other hand, in the non-illumination state, the microcomputer 43 of the control unit 40 drives the drive unit 52 to advance the shielding member 51, thereby shielding the laser light from the laser diode 11 and transmitting the illumination light. Stop irradiation. And the microcomputer 43 of the control part 40 drives the drive part 52, and detects the shielding member 51, when abnormality of illumination light is detected based on the difference of the light quantity detected by the illumination state and the non-illumination state. The state in which the laser beam is shielded by the shielding member 51 can be maintained by moving forward, and thereby the illumination light can be prevented from being irradiated onto the subject.

  As in the present embodiment, the switching between the illumination state and the non-illumination state, and the stop of illumination light irradiation at the time of abnormality may be mechanically performed instead of being electrically performed. In the above description, the shielding member 51 serving as the shielding means is provided between the laser diode 11 and the condensing optical system 15 and shields the laser light. However, the present invention is not limited to this, and the fluorescent member 14 is not limited thereto. It is good also as what shields the illumination light from.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

  In each of the above embodiments, the insertion portion 2 of the endoscope apparatus is a flexible type, but is not limited to this, and is a rigid type provided with a rigid tube instead of the flexible tube portion 2c. Also good. Further, the observation means 6 has the CCD 6b as an image pickup device, but is not limited to this. For example, a CMOS (Complementary Metal Oxide Semiconductor) image sensor may be used as the imaging device. Even in this case, by setting the non-illumination state between the transfer of the signal charge of the last scanning line of one frame and the end of the vertical blanking period, the illumination state and non-illumination are not affected without affecting the image. It is possible to detect an abnormality in illumination light by switching between states.

  Further, in each of the embodiments described above, the illumination unit 10 includes the laser diode 11 that is a light source unit and the fluorescent member 14, but is not limited thereto. For example, even in an illumination unit such as a lamp light source that directly emits white illumination light, it is possible to detect an abnormality in the illumination light without being affected by external light. However, by applying to the illumination means having the laser diode 11 and the fluorescent member 14, it is possible to accurately detect the illumination light so that it is not irradiated to the outside in an abnormal state while providing a small and power-saving illumination means. It has the advantage of being able to.

  Further, in each of the above embodiments, the light detecting means 30 detects light reflected from the inner surface of the illumination optical system 16 among the illumination light from the fluorescent member 14 by the light guide 31 for detection. However, it is not limited to this. For example, a configuration may be adopted in which an optical sensor is provided on the tip side of the fluorescent member 14, that is, the side irradiated with the illumination light, and the detection is performed directly. In addition, the light detection means 30 is configured by the first light sensor 33a, the second light sensor 33b, the third light sensor 33c, and the three light sensors, but is not limited thereto. You may make it detect the light quantity only in a specific wavelength area | region, or the whole wavelength area | region by any one optical sensor. However, as described above, it is possible to detect the abnormality of the illumination light in more detail by detecting and monitoring the amount of light separated into different wavelength regions by a plurality of optical sensors.

It is a whole lineblock diagram showing the external composition of the endoscope apparatus of a 1st embodiment of the present invention. 1 is an overall configuration diagram showing an internal configuration of an endoscope apparatus according to a first embodiment of the present invention. It is a whole block diagram which shows the internal structure of the endoscope apparatus of the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 50 Endoscope apparatus 2 Insertion part 6 Observation means 6b CCD (imaging element)
6c NTSC encoder (video processing circuit)
10 Illumination means 11 Laser diode (light source part)
DESCRIPTION OF SYMBOLS 12 Light source drive part 14 Fluorescent member 30 Light detection means 30a External light shielding plate 31 Light guide for detection (Light transmission member for detection)
32 RGB sensor (light sensor)
40 control part 51 shielding member (shielding means)
52 Drive unit (switching means)

Claims (9)

An endoscope apparatus that has an insertion portion that is inserted into a subject, and that observes the inside of the subject by observation means provided on a distal end side of the insertion portion,
Illumination means for illuminating illumination light;
A light detecting means arranged to detect the amount of the illumination light; and
A control unit that switches the illumination means between an illumination state in which the illumination light is irradiated and a non-illumination state in which the illumination light is not irradiated;
The control unit detects the light amount by the light detection means in the illumination state and the non-illumination state, respectively, and monitors a difference between the light amount in the illumination state and the light amount in the non-illumination state. An endoscope apparatus characterized by the above. The endoscope apparatus according to claim 1, wherein
The illumination means includes a light source unit that emits excitation light in accordance with a supplied current;
An endoscope apparatus comprising: a fluorescent member that is excited by the excitation light and emits the illumination light The endoscope apparatus according to claim 1 or 2,
The endoscope apparatus, wherein the control unit switches from the illumination state to the non-illumination state at a timing not affected by the observation by the observation unit, and detects the light amount in the non-illumination state. The endoscope apparatus according to claim 3, wherein
The observation means is provided on the distal end side of the insertion portion, and an image sensor that photoelectrically converts the received image and outputs it as an image signal;
A video signal processing circuit that generates and outputs a video signal from the image signal output from the imaging device by a method having a blanking period;
The endoscope apparatus, wherein the control unit detects the light amount in the non-illuminated state during the blanking period. The endoscope apparatus according to any one of claims 1 to 4,
The control unit stops irradiation of illumination light to a subject when a difference between the light amount in the illumination state and the light amount in the non-illumination state exceeds a preset threshold value. Endoscope device. The endoscope apparatus according to claim 2, wherein
A light source driving unit for supplying current to the light source unit;
The endoscope apparatus, wherein the control unit switches between the illumination state and the non-illumination state by switching between supply and non-supply of current by the light source driving unit. The endoscope apparatus according to claim 2, wherein
Shielding means for shielding the excitation light emitted from the light source unit or the illumination light emitted from the fluorescent member;
Switching means for switching between shielding and non-shielding of the excitation light or the illumination light by the shielding means,
The said control part drives this switching means, and switches to the said illumination state and the said non-illumination state by switching between shielding and non-shielding by the said shielding means, The endoscope apparatus characterized by the above-mentioned. The endoscope apparatus according to any one of claims 1 to 7,
An endoscope apparatus comprising external light shielding means for shielding light incident on the light detection means from outside. The endoscope apparatus according to any one of claims 1 to 8,
The light detection means includes a light sensor that detects return light that is part of the illumination light emitted from the illumination means;
An endoscope apparatus comprising: a detection light transmission member that guides the return light to the optical sensor.

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