JPH02264912A - Endoscope device - Google Patents

Abstract

PURPOSE:To prevent the burn of the body cavity observing part of a patient and the breakage of a light guide even when a solid-state image pickup element is in a fault or a signal line is disconnected by detecting that the output signal of the solid-state image pickup element is lowered to a fixed level or below when it occurs and outputting the control signal to a light quantity attenuating means. CONSTITUTION:An endoscope device 20 is constituted of an endoscope 21, a light source part 4, a control part 22, and a monitor 23, etc. An object is irradiated with an illuminating light from a light source lamp 58 through a light guide fiber 43. The reflected light is guided to the solid-state image pickup element 38 and converted into an electric signal. When the signal from the solid-state image pickup element 38 is inputted to the controller 22, the irradiating light is controlled by a first compara tor 49, and the object is irradiated with the illuminating light. When the signal is not obtained by the fault of the solid-state image pickup element 38, etc., the first comparator 49 decides that the illuminating light is decreased. Although the signal which increases light quantity is inputted, the signal is interrupted by the signal from an AND circuit 52. Consequently, a standard signal Vr3 which full closes a diaphragm 61 is supplied to a galvanomotor 57 to prevent the increase of irradiating light quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an endoscope apparatus having a light 1 adjustment means for adjusting the amount of light.

[Prior Art and Problems to be Solved by the Invention] In recent years, treatment instruments have been developed that allow observation of internal organs, etc. in body cavities by inserting an elongated insertion portion into body cavities, and that are inserted through treatment instrument channels as necessary. Endoscopes (fiberscopes) that can perform various treatments are widely used.

Furthermore, recently, electronic endoscopes using fixed image carriers such as charge-coupled devices (CODs) as imaging means have been proposed.

Inside this electron? The i4 mirror has advantages such as higher resolution than a fiberscope, easier recording and reproduction of images, and easier image processing such as image enlargement and comparison of two screens.

By the way, the endoscope described above is generally used together with a light source device that outputs illumination light, and this light source device is provided with a light control section. A conventional example having such a light source device is shown in FIG. 11 disclosed in Japanese Patent Laid-Open No. 61-61588.

In FIG. 11, the output signal from the solid-state image sensor 3 built in the distal end 2 of the endoscope 1t1 is taken out from the first signal detection end 4, and is detected for each R, G, and B by the timing signal from the timing generator 6. The signal is guided to an analog switch 7 which is sequentially switched. Then, from the obtained sequential signal, only low frequency components are extracted by a low pass filter 8, and the reference potential vr
1 is input to the negative terminal of the comparator 9 which has the positive terminal added.

Next, the output signal S1 of the comparator 9 is outputted as a drive signal for the aperture member 11, and the light b1 from the lamp 12 is controlled.

By the way, in the above conventional technology, for example, the solid-state image sensor 3
If an accident occurs such as a failure in the signal line, a break in the signal line, or a failure in the circuit up to the first signal detection terminal 4, the negative terminal input signal of the comparator 9 will be Since it is always constant (OV) and is lower than the standard voltage Vr1, the output signal S1 of the comparator 9
is always at the L level, and the aperture member 11 is in an open state. If such an accident occurs during diagnosis, the throttle member 1
Since the condition described in No. 1 continues, a large amount of light is emitted from the tip of the endoscope, and there is a risk of burning the patient's stomach wall or burning and damaging the light guide, for example.

Moreover, although the image transport method has been described above with respect to the frame sequential method, the same applies to the color mosaic method.

In this case, for example, an RGB color filter is pasted on the surface of the solid-state Il carrier, and unlike the field sequential method, an RGB rotation filter is not necessary, so the illumination light emitted from the light source run is attenuated by the RG8 rotation filter. It is more dangerous because it is directly irradiated onto the stomach wall.

The present invention has been made in view of the above-mentioned circumstances, and is capable of preventing burns to the observation site in the patient's body cavity and burnout of the light guide even in the event of failure of the solid-state electronic device, disconnection of the signal line, or failure of the circuit. The purpose is to provide a viewing device.

[Means and effects for solving the problem] The endoscope apparatus of the present invention includes a detection means that outputs a control signal when the signal level of an output signal from a solid-state image sensor becomes a predetermined level or less, and a t11 control. and a light amount attenuation means for attenuating the illumination target set output from the illumination means in response to a signal.

In the present invention, the detection means detects that the output signal of the solid-state image sensor becomes below a certain level, and the detection means outputs a control signal to the light amount attenuation means. The light quantity attenuation means receives the ibl control signal and attenuates the light quantity.

[Example] Hereinafter, an example of the present invention will be specifically described with reference to the drawings.

Figures 1 to 3 relate to the first embodiment of the present invention.
FIG. 2 is an explanatory diagram showing the configuration of the endoscope device, FIG. 2 is an explanatory diagram of the operation of the detection means, and FIG. 3 is an external view of the endoscope device.

In FIG. 3, the endoscope device 20 includes an endoscope 1I 21, a control device W122 having a light source section that supplies illumination light to the private celebration 5fi 21, and a signal processing section that processes the output signal of the endoscope 21.
and a monitor 23 that displays the inner mm*.

The endoscope 121 includes an elongated insertion section 24 and an elongated insertion section 24.
It includes a large-diameter operating section 26 connected to the rear end side, and a universal cable 27 extending from the side of the operating section 26.

A hard distal end portion 28 is provided on the distal end side of the insertion portion 24, and a bendable curved portion 29 is provided on the rear side adjacent to this distal end portion 28. Furthermore, a flexible part 31 is connected to the rear of the curved part 29. The bending portion 29 can be bent vertically and horizontally by operating a bending operation knob 32 provided on the operating portion 26.

A light source connector 33 is provided at the rear end of the universal cable 27, and a control device! ! It is connected to a connector receiver 34 provided at 22.

The control device 22 is connected to the monitor 2 by a signal cable 36.
3 is connected.

In FIG. 1, an objective lens system 37 is provided at the tip 28 of the inner lA1!21, and this objective lens system 37
A decoy image plane of the solid-state image sensor 38 is provided at the imaging position. A preamplifier 39 is connected to this solid-state ms element 38, which furthermore controls @[22
It is connected to the circuit section 40 inside.

Further, a light distribution lens system 42 is provided at the distal end portion 28, and an output end face of a light guide fiber 43 for transmitting illumination light is provided behind the light distribution lens system 42. This light guide fiber 43 is guided to a light source section 44 within the control device 22.

The preamplifier 39 is connected to a video amplifier 41 of a circuit section 40, and the video amplifier 41 is further connected to a memory 46 and resistors R1 and R2.

It is connected to one end of a series circuit consisting of R3.

The other ends of the series resistors R1, R2, and R3 are connected to a ground point, and the one end PG and each intersection PR and PB are connected to a three-way analog switch 47. Each PG, PR,
The signal level of PB is set in order to a level that matches the relative luminous efficiency characteristics of green light, red light, and blue light, so that independent dimming can be performed in each of the three primary color signal periods.

Note that the memory 46 stores RGB data amplified by the video amplifier 41.
After sequentially storing the signals, they are simultaneously read out and output to the monitor 23 to display an endoscopic image on the monitor 23.

The output terminal of the analog switch 47 is connected to a first comparator 49 as a light amount adjusting means via a low-pass filter 48.
and the positive terminal of the second comparator 51. The reference potential Vrl is connected to the positive terminal of the first comparator 49.
A reference potential Vr2 is connected to the negative terminal of the second comparator 51. The relationship between this reference potential Vrl and Vr2 is Vr2
<<Vrl.

In the first comparator 49, the average value (luminance signal) of the signal from the analog switch 47 during each of the three primary color periods is set to the reference potential Vr1.
When the light level decreases further, a dimming control signal $1 is output.

The output terminal of the second comparator 51 is connected to the three-person AND circuit 5.
2 at one end. Other terminals of the AND circuit 52 include a scope detection circuit 53 that detects that the endoscope 21 is connected to the control device 22, and a lamp lighting detection circuit 54 that detects that the lamp 58 of the light source section 44 is lit. is connected.

Note that the second comparator 51 and the three-man AND circuit 52 form an abnormality detection circuit 50 as a detection means.

Further, the output terminal of the first comparator 49 is connected to one input terminal 56a of the changeover switch 56, and the other input terminal 56b is connected to the reference potential Vr3.

Further, this selector switch 56 is connected to the three-person group circuit 5.
The output signal of 2 is used as a switching control signal, and the AND circuit 5
When the signal from No. 2 is 1-level, the input terminal 56a is selected, and when the signal is at L level, the input terminal 56b is selected.

An output terminal 56G of the changeover switch 56 is connected to a galvano motor 57 constituting the light source section 44. This galvano motor 57 is provided between a light source lamp 58 and a parallel light lens 59 that converts the illumination light outputted from the light source lamp 58 into parallel light, and drives an aperture 61 that adjusts the amount of illumination light. It is. In addition, the galvano motor 57
The aperture 61 constitutes a light quantity attenuation means.

The light transmitted through the parallel light lens 59 passes through a color separation filter (not shown) provided on a rotary filter 63 rotationally driven by a motor 62, and is separated into red (R) and green (G), for example.
) and blue (B) color light. This colored light is condensed by a condensing lens 64 and irradiated onto the incident end face of the light guide fiber 43.

The rotary filter 63 is configured such that a rotation detector 66 detects one pulse indicating its rotation start position. This detector 66 is connected to a timing generator 67 and outputs a control signal to the timing generator 67.

The timing generator "a67" is connected to the three-person analog switch 47 and controls switching of the analog switch 47.

That is, the timing generator 67 that receives the pulses detected by the rotation detector 66 is configured to generate the switching pulse S2 every 1/3 rotation of the rotating filter 63, and this switching pulse S2 generates the switching pulse S2. analog switch 4
7 positions can be switched and selected.

The operation of the endoscope device 20 configured as described above will be explained.

When the signal from the solid-state m-image element 38 is first output, the illumination light output from the light source lamp 58 passes through the aperture 61.
The light is then converted into parallel light by a parallel light lens 59, sequentially separated into R, G, and B color lights by a rotating filter 63, and irradiated onto the incident end face of the light guide fiber 43 by a condenser lens 64. The illumination light transmitted through the light guide fiber 43 reaches the tip 28 of the family gift 11121, and is irradiated onto the subject by the light distribution lens system 42. The reflected light of this light is reflected by the objective lens system 37 into a solid IIIi! The image is formed on the image carrying plane of the element 38 and converted into an electrical signal, and the preamplifier 39
and the video amplifier 41, and the RGB three primary color signals as shown in FIG. 2(a) are supplied to the memory 46 and the series resistors R1, R2, and R3. Note that although the RjU diagram shows that the rotating filter 63 is rotating at 30H7, it may be rotated at other than 30H2.

The signal levels of PG, PR, and PB of series resistors R1, R2, and R3 are set in order to levels that match the relative luminous efficiency characteristics of green light, nasal color light, and blue light, and are passed through a low-pass filter 48 as shown in FIG. Obtain an output signal like a). This output signal is input to the positive terminal of the second comparator 51 and compared with the reference potential Vr2 connected to the negative terminal. This reference potential V
Since r2 is even smaller than the output signal of the low-pass filter 48, the a signal, which is the output signal of the second comparator 51, becomes a torque signal and is input to the AND circuit 52.

The AND circuit 52 also receives the Trubel's b signal from the Shubbe detection circuit 53 which indicates that the endoscope 1!21 is connected, and the indicator lamp lighting detection circuit 54 which indicates that the light source lamp 58 is lit. The d signal, which is the output signal, becomes the trubel, and
The signal is supplied to the changeover switch 56. The selector switch 56 is connected to the input terminal 56 by inputting the Trubel d signal.
Select a.

On the other hand, the first comparator 49 has the low-pass filter 48
The output signal is input to the negative terminal and compared with the reference potential Vr1 connected to the positive terminal, and if the input signal is larger than the reference potential r1, the dimming control signal S1 is output as a torque signal. This dimming i control signal S1 is supplied to the changeover switch 56, but since the input terminal 56a side is selected, the trubel dimming I control signal @S1 is supplied to the galvano motor 57. The galvano motor 57 drives the diaphragm 61 using this signal S1 so that the amount of light decreases. Further, when the input signal is smaller than the reference potential Vr1, the dimming control signal S1 is output as a torque signal, and the galvano motor 57 drives the diaphragm 61 to increase the amount of light as described above.

In this way, when the signal from the solid-state Il image element 38 is input, the first comparator 49 performs dimming.

On the other hand, if the illumination light is being irradiated onto the subject but no signal is generated manually due to a failure of the solid-state image sensor 38 or a poor connection of the signal line, the following will occur.

In FIG. 2(b), when the signal from the solid-state image sensor 38 is not input, the output of the low-pass filter 48 becomes a signal at a level lower than the reference potential Vr2, and the negative terminal of the first comparator 49 and the It is input to the positive terminal of comparator 51 of No. 2. Since the level of the second comparator 51 is lower than the reference potential Vr2, the output signal a signal becomes a torque signal and is input to the AND circuit 52. The d signal, which is the output signal of the AND circuit 52', becomes a torque level because the a signal becomes a torque level. The changeover switch 56 selects the input terminal 56b side because the d signal becomes the torque level.

On the other hand, in the 19th comparator 49, since the output signal of the low-pass filter 48 has become lower than the reference potential Vr1 (Vr2<<Vrl), the dimming control signal S1 is set as a torque level even though lighting is being performed, and the selector switch is switched. 56. However, since the input terminal 56b side is selected in the changeover switch 56, the dimming control signal S1 is not supplied to the galvano motor 57, but the reference potential vr3 connected to the input terminal 56b is supplied. The reference potential Vr3 is supplied to the galvano motor 57 to fully open the diaphragm 61.

Table 1 summarizes the above operations.

Table 1 In Table 1, the b signal controls the endoscope 21 from the control device 2.
When connected to 2, it becomes H level, and when it is disconnected, it becomes L level.
level. Furthermore, in the C signal, the light source lamp 58
When it lights up, it becomes H level, and when it goes out, it becomes H level.

In this embodiment, when a signal cannot be obtained due to a failure of the solid-state Al element image 38 or a poor signal line connection, the first comparator 49 determines that the illumination light has decreased and increases the light amount. However, this signal is blocked by the signal from the AND circuit 52, and a reference potential Vr3 for fully opening the diaphragm 61 is instead supplied to the galvano motor 57. Therefore, the solid-state image sensor 38
Even when no signal is input from the device, the amount of illumination light can be prevented from increasing, and burns in the patient's body cavity and burnout of the light guide fiber can be prevented.

4 and 5 relate to a second embodiment of the present invention, in which FIG. 4 is an explanatory diagram showing the configuration of an endoscope apparatus, and FIG. 5 is an explanatory diagram of a turret plate.

This embodiment uses a light source lamp 58 and a light guide fiber 43.
A turret plate 71 is provided on the optical path connecting the incident end face of the light beam. As shown in FIG. 5, this turret plate 71 has a disk shape and is arranged around a halogen lamp 7 as an auxiliary light source.
2, an opening 73, a light shielding part 74, and a mesh filter 76
and is provided. The halogen lamp 72 is inserted on the optical path to output illumination light when the light source lamp 58 fails, and the opening 73 is placed on the optical path in the case of normal illumination so that the illumination light passes through. It has become. The mesh filter 76 is inserted on the optical path to attenuate the illumination light, and the light shielding section 74 is inserted on the optical path to shield the illumination light when a signal from the solid-state image sensor 38 cannot be obtained. This turret plate 71 is driven by a turret plate driving motor 78, and this motor 78 is
It is connected to U77 and its rotation is controlled by 111 degrees.

The CPLJ 77 is connected to the output terminal of the three-person AND circuit 52 described in the first embodiment, and it is determined whether a signal from the solid-state Illll elementary image 38 is being obtained or not.

The other configurations are the same as in the first embodiment.

In this embodiment, when the signal from the solid-state image sensor 38 cannot be obtained, the d signal of the output signal of the abnormality detection circuit 50 becomes L level and is input to the CPU 77 as in the first embodiment.

When the CPU 77 receives the L signal d signal, it drives the turret plate driving motor 78 so that the illumination light output from the light source lamp 58 is blocked by the light blocking portion 74 . Note that the light a irradiated onto the light guide fiber 43 can be reduced by inserting not only the light shielding part 74 but also a mesh filter 76 and a halogen lamp 72 for emergency lighting on the optical path.
You may dim the light.

Further, the CPU 77 may receive an abnormality signal and display a message on the monitor 23 to notify the patient of danger, thereby protecting the safety of the patient.

The above is summarized and shown in Table 2.

Table 2 Other functions and effects are similar to those of the first embodiment.

6 to 8 relate to the third embodiment of the present invention, and FIG.
7 is an explanatory diagram of the configuration of the abnormality detection circuit, FIG. 7 is a circuit diagram of the timer, and FIG. 8 is a timing chart diagram illustrating the operation of the timer.

In this embodiment, an abnormality detection circuit 81 is provided with a timer 82 and a changeover switch 83 in addition to the configuration described in the first embodiment.

The low-pass filter 48 is connected to the positive terminal of the second comparator 51 of the abnormality detection circuit 81, and the reference potential Vr2 is connected to the negative terminal of the second comparator 51.
They are connected in the same way as in the embodiment. The output terminal of the second comparator 51 is connected to a timer 82;
2 is connected to one input terminal 83a of the changeover switch 83. The other input terminal 83b of the changeover switch 83 is always at H level.

The output terminal 83c of the changeover switch 83 is connected to the input terminal of the three-man AND circuit 52, and the other input terminals are connected to the scope detection circuit 53 and lamp lighting detection circuit 54 as in the first embodiment. .

The switching of the changeover switch 83 is controlled by a control signal from the diagnostic detection circuit 84. For example, in the diagnostic detection circuit 84? JHI! Diagnosis is being performed by any one or a combination of actions performed during diagnosis, such as bending the bending portion 29 of 21, supplying air or water, or freezing or releasing the camera. If it is determined that a diagnosis is in progress, the terminal 83a on the timer 82 side is switched to, and if the diagnosis is not in progress, the terminal 83b is switched to set the α signal to H level.

Further, the timer 82 is provided to prevent the diaphragm 61 from being fully closed in response to an extremely low level signal due to the subject.

The operation of the timer 82 will be explained using FIGS. 7 and 8.

In the case of an abnormality in which the output signal from the solid-state Jllll elementary image 38 cannot be obtained, the α signal from the second comparator 51 becomes L level and is input to the inverter 89 and the OR circuit 88 . The α signal is inverted by an inverter 89, and this inverted signal is input to the CCLR terminal of the counter 86.

A signal obtained by dividing the vertical synchronization signal VD from the timing generator 67 by a frequency divider 87 is input to the CK terminal of the counter 86. This signal is used as the clock for the counter 86 to start counting, and Ts After counting, an H level signal is input from the output terminal Q to the CCKEN terminal and the inverter 91. The CCKEN terminal is disabled by inputting this signal, and the output signal from the output terminal Q is held at H level. Therefore, the "a" signal of the inverter 91 becomes TS from the time it becomes abnormal (the time when the L level signal is input to the OR circuit 88).
It becomes ill and becomes L level. The a# signal at the L level is logically summed with the α signal in the OR circuit 88, and the a' signal at the L level is sent to the AND circuit 5 via the terminal 83a of the changeover switch 83.
2 is input.

Here, if a signal that is even slightly larger than the reference potential Vr2 is input to the second comparator 51 before the counter 86 counts TS, the α signal becomes H level and the a of the reor circuit 88
'The signal becomes H level and the abnormal state is canceled. Therefore, it is possible to prevent a signal of a minimum level from being mistakenly determined to be "abnormal."

Note that when the changeover switch 83 is determined to be under diagnosis by the diagnosis detection circuit 84, the input terminal 83b side is selected and the H level signal is input to the AND circuit 52, and the signal from the second comparator 51 is set to the L level. Even if the level reaches that level, it will not be considered abnormal.

The output of the AND circuit 52 is the changeover switch 56 of the first embodiment.
The data may be input to the CPU 77 of the second embodiment.

In this embodiment, a timer 82 is provided to allow time to pass before determining that there is an abnormality, so that even if a minimal level signal is input to the abnormality detection circuit 81, the aperture 61 will not operate.

Other configurations, operations, and effects are the same as those in the first and second embodiments.

9 and 10 relate to the fourth embodiment of the present invention, and FIG.
The figure is a circuit diagram of the comparator, and FIG. 10 is an explanatory diagram of the operation of the comparator.

In this embodiment, the second comparator 96 is a Schmitt trigger circuit.

The input signal VIN containing noise is input to the negative terminal of the second comparator 96 via the resistor R3, and the positive terminal is connected to one end of the resistor R2 as well as one end of the resistor R1. The other end of the resistor R1 is connected to the reference potential Vr2 and to a series-connected Zener diode 97°98 with reversed polarity. The positive and negative terminals of the comparator 96 are connected by a diode 99.degree. 101 whose polarity is reversed. The output terminal of the comparator 96 is connected to one end of the resistor R4, and the other end of the resistor R4 is connected to the other end of the resistor R2 and the Zener diode 97.98.

In this embodiment, since the comparator 96 is a Schmitt trigger circuit, it is resistant to noise and has stable operation.

That is, if only the comparator 96 is used for the input signal VIN containing noise as shown in FIG. 10, the noise component will be applied to the reference potential ■r2, resulting in malfunction and instability. On the other hand, in the case of a Schmitt trigger, the resistor R1,
To obtain the hysteresis voltage χIVP-P set by R2, tS?
! It is stable without causing movement.

In this embodiment, it is possible to construct an abnormality detection circuit that is stable against input signals containing noise.

Other configurations, operations, and effects are the same as those in the first and second embodiments.

Although each of the above embodiments has been described with respect to an endoscope device that uses a field-sequential image conveyance method and has a rotating filter, the present invention can also be applied to a color mosaic type endoscope device. . In this case, the same effect can be obtained by switching the switching control signal S2 from the timing generator 67 to the three-person analog switch 47 on a field or frame basis.

Furthermore, the present invention may also be applied to an optical endoscope having an image guide, which is externally attached to an optical endoscope of the above-mentioned field sequential type or color mosaic type image conveyance type, and is connected to a television camera.

[Effect of the Invention 1] As explained above, according to the present invention, the solid-state image sensor It is possible to prevent burns in the patient's body cavity observation section and burnout of the light guide even if the sensor is out of order, the signal line is disconnected, or the circuit is out of order.

[Brief explanation of drawings]

Figures 1 to 3 relate to the first embodiment of the present invention.
FIG. 2 is an explanatory diagram showing the configuration of the endoscope device, FIG. 2 is an explanatory diagram of the operation of the detection means, FIG. 3 is an external view of the endoscope device, and FIGS. 4 and 5 are the second diagram of the present invention. 4 is an explanatory diagram showing the configuration of the endoscope device, FIG. 5 is an explanatory diagram of the turret plate, and FIGS. 6 to 8 are related to the third actual droplet example of the present invention, and FIG. 6 is an explanatory diagram of the configuration of the abnormality detection circuit, FIG. 7 is a circuit diagram of the timer, FIG. 8 is a timing chart diagram explaining the operation of the timer, and FIGS. 9 and 10 are a fourth embodiment of the present invention. 9 is a circuit diagram of a comparator, FIG. 10 is an explanatory diagram of the operation of the comparator, and FIG. 11 is an explanatory diagram showing the configuration of an endoscope apparatus according to the prior art. 20... Endoscope device 2.1... Inside? JltA22
...Control bag V1 23...Monitor 38...Fixed image sensor 40...Circuit section 44...Light source section 46.
... Memory 50 ... Abnormality detection circuit 51 ... Second comparator 52 ... Three-person AND circuit 56 ... Changeover switch 57 ... Galvano motor 61
...Aperture 8th drawing 9th drawing Vrz Procedure Nefusho (spontaneous)

Claims (1)

[Scope of Claims] An illumination means for illuminating the inside of a cavity, a solid-state image sensor that converts a subject image obtained by the illumination means into an electrical signal, and the illumination means based on an output signal from the solid-state image sensor. a light amount adjustment means for adjusting the light amount of the illumination device, the endoscope apparatus comprising: a detection means for outputting a control signal when the output signal level from the solid-state image sensor becomes a predetermined level or less; An endoscope apparatus comprising: a light amount attenuation means for attenuating the amount of illumination light outputted by the means.