JP2716754B2 - Endoscope device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an endoscope apparatus, in particular, an optical endoscope such as a fiberscope, which is equipped with an external TV camera,
The present invention relates to an endoscope apparatus that converts at least a part of an electric signal from a TV camera into an optical signal and transmits the optical signal through an optical cable.

[Prior Art] In recent years, an electronic endoscope using a solid-state imaging device such as a charge-coupled device (CCD) instead of an image guide for transmitting an optical image has been put into practical use. Attaching an external TV camera with built-in CCD or other imaging means to the eyepiece of an optical endoscope such as a fiberscope using a conventional image guide with the ability to display on a monitor In addition, the taken endoscope image is displayed on a TV monitor.

However, in order to display an endoscope image with such a configuration, a plurality of electric cables are required to connect the endoscope, an external camera, and a light source device that supplies illumination light to the endoscope. Thus, the kinks of the plurality of electric cables and the weight of the cables are increased, and the operability of the endoscope is significantly reduced.

Therefore, the applicant of the present application has previously filed Japanese Patent Application No. 63-2043,
A proposal has been made to eliminate the above drawbacks.

Next, the means proposed in Japanese Patent Application No. 63-2043 will be described with reference to the block diagram of FIG. This prior art endoscope apparatus 1 supplies a fiber scope 2, an external TV camera 3 attached to an eyepiece 15 of the fiber scope 2, and illumination light connected to the fiber scope 2. A light source device 4, a camera control unit (hereinafter, referred to as a CCU) 5 connected to the light source device 4 and performing signal processing, and a TV monitor 6 that displays a video signal output from the CCU 5 as an endoscope image It is configured.

The fiber scope 2 includes an elongated insertion portion 7, a large-diameter operation portion 10 provided continuously behind the insertion portion 7, and a universal cable extending from a side portion of the large-diameter operation portion 10.
It has 16 and.

A light guide 8 for transmitting illumination light is inserted into each of the insertion section 7 and the universal cable 16, and a connector section 10 provided at a distal end of the universal cable 16.
a is connected to the light source device 4 so that the light guide 8
The light amount of white light emitted from a light source lamp 9 such as a xenon lamp is adjusted by a dimming light-shielding member 11, and the white light emitted from a light source lamp 9 is condensed and irradiated by a condenser lens 12.

The light guide 8 allows the illumination light to pass through the insertion section 7.
The light is transmitted toward the target object through the light distribution lens 13. The object illuminated by the illumination light forms an image on the incident end face of the image guide 17 inserted through the insertion section 7 by the objective lens 14. The exit end face of the image guide 17 is disposed opposite to the imaging lens 18 of the external TV camera 3 which is detachably attached to the eyepiece 15 provided on the rear end side of the operation section 10 for transmission. The formed optical image is formed on the imaging surface of a solid-state imaging device (CCD) 19 by the imaging lens 18. On the imaging surface of the CCD 19, for example, an RGB mosaic filter 21 for color is provided.

The CCD 19 outputs an image signal (video signal) photoelectrically converted by application of a drive signal from a CCD drive circuit 22 provided in the external TV camera 3, and this image signal is output to a CDS circuit (correlated double). 1 / f noise and the like generated from the CCD 19 after being input to the sampling circuit 23 and double-sampled. The output of the CDS circuit 23 is a video information signal, which is input to the FM modulator 24 and is FM-modulated. Then, the FM-modulated video signal is input to the mixer 27.

The video information signal from the CDS circuit 23 is also input to a video level detection circuit (DET) 26, where the video signal output from the CDS circuit 23 is detected and a DC signal having a magnitude proportional to the photoelectric conversion output level of the CCD 19 Is converted to This DC signal is input to the mixer 27 as an automatic dimming signal, and is superimposed on the video signal. Note that the output of the FM modulator 24 does not include a DC component because it is modulated. Therefore, even if the DC component of the signal for automatic light control is superimposed, no obstacle such as interference occurs.

The external TV camera 3 is provided with a microphone 28 through which a voice can be input by an operator. The output of the microphone 28 is amplified by an audio amplifier 29, input to an audio FM modulator 31 dedicated to audio, and FM-modulated. The FM modulated wave output from the audio FM modulator 31 is input to the mixer 27.

The output of the mixer 27 is applied to a connector terminal provided at a position facing the eyepiece 15. This connector terminal is connected to a connector pin 32 of the fiberscope 2 when the external TV camera 3 is attached to the eyepiece 15 of the fiberscope 2.
The output of the mixer 27 is transmitted to a signal line 33 as a dimming control signal supply line, through which the operation unit 10 and the universal cable 16 are inserted, via the 32. This signal line 33 is connected to a connector pin 34 provided in the connector section 10a,
When the connector section 10a is connected to the light source device 4, an FM modulated wave can be input to a low-pass filter (LPF) 36 in the light source device 4.

The cutoff frequency of the LPF 36 is designed to separate and extract 0-100 Hz, and the extracted automatic dimming signal is input to the dimming circuit 37. The dimming circuit 37 controls the dimming light shielding member 11 to adjust the amount of illumination light.

A power supply circuit 49 is provided in the light source device 4. The power supply circuit 49 supplies power to the light source lamp, and connects the universal cable 16 and the operating unit via a connector pin 51 provided in the connector unit 10a. 10 is connected to the signal line 52 inserted. This signal line 52 is connected to a connector pin 53 provided on the eyepiece 15 and an external pin connected to the same pin 53.
Through a connector terminal on the TV camera 3 side, it is connected to a circuit power supply 54 for supplying power to electric accessories in the external TV camera 3, thereby supplying power.

The FM modulated wave input to the light source device 4 is input to the LPF 36 and is branched therefrom.
Is output to

By the way, the FM modulation wave input to the CCU 5 is converted into a high-pass filter (HPF) and a band-pass filter (BPF) (not shown).
Entered as In the HPF, a video FM modulated wave is separated and extracted, and input to a video demodulator (not shown) to demodulate the video signal. The demodulated video signal is subjected to addition of a synchronization signal, color signal processing, and the like by a video processing circuit (not shown).
For example, it outputs an NTSC composite video signal.

On the other hand, the BPF separates and extracts a frequency band representing a voice FM modulation wave, inputs the extracted voice component to a voice demodulator (not shown), demodulates and outputs the voice component. Then, the NTSC composite video signal and the audio signal are input to the TV monitor, and the endoscope image of the object is displayed on the screen, and the audio is reproduced.

The light source device 4 has a built-in air supply and suction pump 44. The pipe line 46 connected to the air supply and suction pump 44 is connected to a pipe line 47 in which the insertion section 7 and the universal cable 16 are inserted and a connection section 4 provided in the connector section 10a.
It is detachably connected by 8 and serves to supply air to the distal end surfaces of the light distribution lens 13 and the objective lens 14 or to suction an object.

As described above, according to the means proposed in Japanese Patent Application No. 63-2043, the signal line 33 for dimming control of the external TV camera 3 is provided.
To transmit FM modulated wave and external TV camera 3
By supplying power to the circuit power supply 54 through a signal line 52 as a power supply line for the automatic light control circuit, the external TV camera 3
Thus, the operability can be greatly improved without directly connecting a signal cable to the CCU 5 and without modifying the fiberscope 2.

[Problems to be Solved by the Invention] However, in the means of Japanese Patent Application No. 63-2043, since an electric signal is transmitted through a signal line, there is a problem that noise is generated from the signal line. In addition, as the number of peripheral devices increases, noise increases accordingly, and this noise adversely affects other signal lines,
There is a possibility that the radiation noise exceeds the limit value of the radiation noise defined for the entire endoscope apparatus, and that the scope may be leaked.

The present invention has been made in view of the above circumstances,
An object of the present invention is to provide an endoscope apparatus in which one signal line does not adversely affect other signal lines, the entire endoscope apparatus does not exceed the limit of radiation noise, and the scope does not leak. I do.

[Means for Solving the Problems] An endoscope apparatus according to the present invention includes an optical endoscope and an external TV having an image pickup means and detachably attachable to an eyepiece of the optical endoscope. An endoscope apparatus comprising: a camera, a light source that supplies illumination light to the optical endoscope, and a camera control unit that processes an image signal obtained by the imaging unit. Electro-optical conversion means for converting at least a part of the electrical instruction signal to an optical signal, and selecting means for selecting a luminance level of the optical signal,
An optical cable for transmitting the optical signal, and an optical-electrical conversion unit for converting the optical signal transmitted by the optical cable into an electric instruction signal again and transmitting the same to the camera control unit are provided.

[Operation] That is, in the endoscope apparatus of the present invention, after at least a part of the electric signal output from the external TV camera is converted into an optical signal after selecting a luminance level and transmitted through an optical cable, Are again converted into electric signals and applied to the camera control unit.

[Embodiment] Each embodiment of the present invention will be described below with reference to the accompanying drawings.

1 and 2 relate to a first embodiment of the present invention. FIG. 1 is a block diagram showing an endoscope apparatus, and FIG. 2 is a block diagram showing an optical receiving circuit.

As shown in FIG. 1, an endoscope apparatus according to the present embodiment includes a light source device 60, a fiberscope 70, and an external TV camera 80.
And a CCU 120 and a monitor 130.

The light source device 60 includes a light emitting lamp 61 and a condenser lens 62, and the light source device 60 and the fiberscope 70
Is connected, the light emitted from the lamp 61 is applied to the incident end face of the light guide 71 of the fiberscope 70 via the condenser lens 62.

This illumination light is guided to the distal end of the fiber scope 70 by the light guide 71. At the tip, an illumination lens 72 and an objective lens 73 are provided, so that light emitted from the emission end of the light guide 71 is directed toward a subject via the illumination lens 72. Has become.

The reflected light from the subject is imaged by the objective lens 73 on the incident end face of the image guide 74 inserted into the fiber scope 70. An imaging lens 75 is provided on the emission end face of the image guide 74, and the optical image transmitted through the image guide 74 is transmitted to the CCD 82 in the external TV camera 80 by the imaging lens 75. An image is formed on an imaging surface. Note that a mosaic filter 81 such as R, G, B for color is provided on the imaging surface of the CCD.

The image signal photoelectrically converted by the CCD 82 is input to a signal processing circuit 83, and the signal processing circuit 83
, Various signal processings are performed. The processed image signal is transmitted through a signal line 84. The signal line 84 is connected to the signal line 78 of the fiberscope 70 via the connector 77 of the fiberscope 70 that is in contact with the connector 85 of the external TV camera 80.

On the other hand, the external TV camera 80 is provided with a freeze switch 86 for generating an electric instruction signal for stopping an image on a monitor and a release switch 87 for generating an electric instruction signal for recording a still image. ing.

When the freeze switch 86 is pressed, a resistor 88 is pressed, and when the release switch 87 is pressed, a resistor 89 is pressed.
And a photodiode 91 such as an LED. The light emitted from the optical cable light source is
To be incident on.

The optical cable 92 is connected to the optical cable 76 in the fiberscope 70. The optical cable 76 is connected to the optical cable 69 in the light source device 60.

An optical receiving circuit 63 is provided at the emission end of the optical cable 69. The light receiving circuit 63 has a configuration as shown in FIG. 2, and the light emitted from the emitting end of the optical cable 69 is applied to the base of the photo transistor 141.

A current corresponding to the luminance level of the light is passed through the collector of the photon transistor 141, and a voltage is applied to the inverting input terminal of the comparator 147 and the non-inverting input terminal of the comparator 148. I have.

The emitter of the photo-transistor 141 is grounded, and the collector is connected to, for example, a 5V power supply through a resistor 142. A voltage of, for example, 3 V is applied to a non-inverting input terminal of the comparator 147 by a voltage dividing circuit of a resistor 143 and a resistor 144.
The inverting input terminal of the comparator 148 has a resistor 145 and a resistor 146.
, A voltage of, for example, 1.5 V is applied.

Then, a 2-bit signal output from the output terminal of each of the comparators 147 and 148 is output from the output terminals 63a and 63b as a signal indicating the operation state of the freeze switch 86 or the release switch 87.

The 2-bit signal is transmitted to the signal line 115 via the connector 65 and the connector 114 in contact therewith, and further transmitted to the CCU 120 via the connector 116 and the connector 121. After various processes are performed by the CCU 120, an image is displayed on the monitor 130.

The connector 79 of the fiberscope 70 connected to the signal line 78 contacts the connector 66 of the light source device 60, and the other end of the signal line 67, one end of which is connected to the connector 66, is connected to the connector 68. Have been. The signal line 1 having one end connected to the connector 111 that contacts the connector 68
12, the other end is connected to a connector 113, and the connector 113 is connected to an input terminal 122 of the CCU 120.

Next, the operation of the endoscope apparatus of the present embodiment configured as described above will be described below.

The light emitted from the lamp 61 into the light source device 60 is transmitted to the light guide 71 inserted through the scope 70 by the condenser lens 62.
Is condensed on the incident end face of. Then, the illumination light is guided to the distal end of the fiber scout 70 through the light guide 71, and is emitted toward the subject.

Then, the reflected light image from the subject is formed on the incident end face of the image guide 74 by the objective lens 73. This image is
The light is transmitted through the image guide 74, is emitted from the emission end face thereof, and is transmitted by the imaging lens to the CCD 82 in the external TV camera 80.
Is imaged on the imaging surface of. This image is decomposed into three color signals by a mosaic filter 81 provided on the front surface of the CCD 82, photoelectrically converted by the CCD 82, and then processed by a signal processing circuit 83.

Then, the signal line 84 in the external TV camera 80 and the connector
85, a connector 77, a signal line 78 and a connector 79 in the fiberscope 70, and a connector 66 and a signal line 67 in the light source device 60.
The signal is sent to the CCU 120 by the connector 122 through the connector 68, the connector 111, the signal line 112, and the connector 113. Then, an observation image is displayed on the monitor 130 based on the signal controlled by the CCU 120.

When performing such image display, the external TV
When the freeze switch 86 and / or the release switch 87 of the camera 80 are pressed, the resistors 88 and / or 89 are respectively connected to the light source for the optical cable. This light source for an optical cable includes the resistor 90 and the LED 91 as described above.

The values of these resistors 88, 89 and 90 are 500Ω, 300Ω and 500Ω in the present embodiment, respectively.

Here, assuming that the freeze switch 86 is SW1 and the release switch 87 is SW2, the LED 91 has a fleece switch
According to the on / off state of the switch 86 and the release switch 87, a current having a value as shown in the following Table 1 flows. That is The luminance level of the light emitted from the LED 91 changes depending on the magnitude of the current flowing through the LED 91. In other words, an optical signal having a different luminance level is emitted from the LED 91 in accordance with the on / off state of the freeze switch 86 and the release switch 87. This optical signal is transmitted to the optical receiving circuit 63 through the optical cable 92, the optical cable 76 in the fiber scope 70, and the optical cable 69 in the light source device 60. In the optical receiving circuit 63, as shown in FIG. 2, a phototransistor 141 converts an optical signal into an electric signal, and
Send to 8.

Here, assuming that the voltage of the electric signal is Vs, the comparator
The voltage applied to the non-inverting input of 147 and the comparator 1
The voltages applied to the 48 inverting inputs are 3V and 1.5V, respectively.
Therefore, the level states at the output terminals 63a and 63b of the optical receiving circuit 63 are as shown in the following Table 2 depending on the on / off states of the freeze switch 86 (SW1) and the release switch 87 (SW2). .

Such a level signal is output from the output terminals 63a, 63a of the optical receiving circuit 63.
Since the signal is output from b, the state of the freeze switch 86 or the release switch 87 can be determined based on this signal. Then, this signal is transmitted to the connector 65 and the connector 114.
Is transmitted to the CCU 120 through the signal line 115, the connector 116, and the connector 121. The CCU 120 performs a freeze operation and / or a release operation based on the determination signal to display a still image on the monitor 130 or to record a still image.

As described above, according to the present embodiment, when the freeze switch and / or the release switch are pressed, light having different luminance levels is transmitted via the optical fiber, and the freeze switch and / or the Alternatively, the pressed state of the release switch is identified. As described above, since the freeze instruction signal and the release instruction signal are transmitted through the optical cable, noise due to the signal line can be reduced.

FIG. 2 is a block diagram showing an endoscope apparatus according to a second embodiment of the present invention. The second embodiment is different from the first embodiment in that the signal processing circuit 83 transmits the signal through the signal line 84.
Are converted into optical signals by the LEDs 96a, 96b, and 96c, and the optical cables 97a, 97b, and 97c, and the optical cables 101a and 101c.
The light signal is transmitted to the light source device 60 through the light emitting devices b and 101c, and the light signal is received by the phototransistors 102, 103 and 104, and is amplified. In addition, resistors 105, 106, and 107 are connected to the phototransistors 102, 103, and 104, respectively. In addition, a click-type freeze / release switch 93 is provided in place of the freeze switch 86 and the release switch 87. At the tip of the freeze / release switch 93, three types of filters 94a, 94b, A light 94c is provided so that the light emitted from the LED 91 is changed to light having a different luminance level depending on the operation state of the freeze / release switch 93.
The subsequent signal flow is the same as in the first embodiment.
A power supply 95 for the signal processing circuit 83 is also provided.

The other configuration of the second embodiment is the same as that of the first embodiment, so that the same operation and effect as those of the first embodiment can be obtained. In addition, in the second embodiment, since the signal from the signal processing circuit is also transmitted through the optical cable, noise can be further reduced as compared with the first embodiment.

[Effects of the Invention] As described above, according to the present invention, at least a part of the signal from the external TV camera is converted into an optical signal after selecting a luminance level, and is transmitted through the optical cable. In addition to transmitting a plurality of signals through one signal line, noise from the signal line can be reduced, adversely affecting other signal lines, and reducing the radiation level of the entire endoscope apparatus. It is possible to provide an endoscope apparatus that does not exceed the limit value and does not cause a leak in the scope.

[Brief description of the drawings]

1 and 2 relate to a first embodiment of the present invention.
FIG. 2 is a block diagram showing an endoscope apparatus, FIG. 2 is a block diagram showing an optical receiving circuit, FIG. 3 is a block diagram showing an endoscope apparatus according to a second embodiment of the present invention. FIG. 4 is a block diagram showing an endoscope apparatus according to the prior art of the present invention. 60 Light source device 63 Optical receiving circuit 70 Fiberscope 69, 76, 92, 97a, 97b, 97c, 101a, 101b, 101c Optical cable 91, 96a, 96b, 96c LED 102, 103, 104, 141 Photo Transistor 120 …… CCU 130 …… Monitor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Atsushi Kibaru, Inventor 2-43-2, Hatagaya, Shibuya-ku, Tokyo Inside O-Limpus Optical Industry Co., Ltd. (72) Yoshinao Daiaki 2-43-2, Hatagaya, Shibuya-ku, Tokyo O-Limpus Optical Co., Ltd. (72) Inventor Shigeru Nakajima 2-43-2, Hatagaya, Shibuya-ku, Tokyo O-Limpus Optical Co., Ltd. (72) Inventor Shinsho Yasukuya 2-43-2, Hatagaya, Shibuya-ku, Tokyo No. Oh-Limpus Optical Industry Co., Ltd. (72) Inventor Shinichiro Hattori 2-43-2 Hatagaya, Shibuya-ku, Tokyo In-Olympus Optical Industry Co., Ltd. (72) Inventor Akihiko Miyazaki 2-43-2, Hatagaya, Shibuya-ku, Tokyo No. Olympus Optical Co., Ltd.

Claims (1)

(57) [Claims] 1. An optical endoscope, an external TV camera having an image pickup means and detachably attached to an eyepiece of the optical endoscope, and illuminating light to the optical endoscope. In an endoscope apparatus including a light source to be supplied and a camera control unit that processes an image signal obtained by the imaging unit, at least a part of an electric instruction signal output from the external TV camera is converted into an optical signal. Electro-optical conversion means for converting; selecting means for selecting a luminance level of the optical signal; an optical cable for transmitting the optical signal; and an optical signal transmitted by the optical cable, which is again converted to an electric instruction signal and the camera An endoscope apparatus, comprising: a light-to-electric conversion unit that transmits the light to the control unit.