JP4887063B2 - Electronic endoscope - Google Patents

Description

  The present invention relates to an electronic endoscope that transmits a signal representing an image of an observation site of a subject to a processor device by radio waves.

  Conventionally, medical diagnosis using an electronic endoscope has been actively performed in the medical field. An imaging element such as a CCD is built in the distal end of the insertion portion that is inserted into the subject of the electronic endoscope. An image in the subject (hereinafter sometimes referred to as an endoscopic image) is generated by performing signal processing on the imaging signal acquired by the CCD with a processor device. While observing the endoscopic image on a monitor, the surgeon operates the electronic endoscope to make a diagnosis.

  Conventionally, an electronic endoscope and a processor device are connected by a signal cable, but recently, a so-called wireless electronic endoscope system in which the signal cable is removed has been devised (see Patent Documents 1 and 2). In this system, a modulation unit that modulates a signal into radio waves, a transmission unit that transmits radio waves to an electronic endoscope, a reception unit that receives radio waves, and a demodulation unit that demodulates radio waves into original signals It is provided so that signals can be exchanged by radio waves.

  In the wireless electronic endoscope system, when the electronic endoscope is used, the operation restriction by the signal cable is eliminated, and the operability is improved. In addition, in a conventional electronic endoscope system using a signal cable, it is essential to maintain a dielectric breakdown voltage of about 4 kV between a patient circuit on the electronic endoscope side and a secondary circuit on the processor device side. In the wireless electronic endoscope system, since there is no electrical connection by a signal cable between the electronic endoscope and the processor device, a configuration for maintaining a high withstand voltage as described above becomes unnecessary.

JP 60-48011 A JP 2001-46334 A

  In a wireless electronic endoscope, a tuning circuit is required to transmit radio waves at a specific frequency. However, in Patent Documents 1 and 2, the tuning circuit is not specifically described, and measures against radio wave interference are provided. Has not been made.

  The present invention has been made in view of the above problems, and an object thereof is to provide an electronic endoscope that can prevent radio wave interference with an inexpensive configuration.

  In order to achieve the above object, the present invention provides an electronic endoscope that acquires an image of an observation site of a subject and transmits a signal representing the image to a processor device by radio waves, and is inserted into the subject. An inductor of a tuning circuit for transmitting at least a portion of the flexible tube at a specific frequency, the flexible tube being formed of a spirally wound metal that forms a flexible portion of the insertion portion It is used as.

  It is preferable to provide first switching means for changing the frequency by connecting a plurality of taps to the portion of the flexible tube used as the inductor and selectively switching the connection to the plurality of taps. Alternatively, it is preferable that a capacitor of the tuning circuit connected in parallel to the inductor is a capacitance variable capacitor, and a second switching unit that changes the frequency by selectively switching the capacitance of the capacitance variable capacitor is provided.

  It is preferable that the portion of the flexible tube used as the inductor is electrically insulated from other members constituting the flexible portion excluding wiring connected to the tuning circuit.

  It is preferable that two flexible tubes having opposite spiral directions are arranged on the outer side and the inner side, and one flexible tube is used as the inductor and is electrically insulated from the other flexible tube.

  According to the electronic endoscope of the present invention, at least a part of a spirally wound metal flexible tube that forms a flexible portion of an insertion portion to be inserted into a subject is subjected to radio waves at a specific frequency. Therefore, it is possible to prevent radio wave interference with an inexpensive configuration.

  In FIG. 1, the electronic endoscope system 2 includes an electronic endoscope 10 and a processor device 11. The electronic endoscope 10 and the processor device 11 exchange signals with radio waves 12 (for example, transmission / reception frequency band 300 to 400 MHz).

  The electronic endoscope 10 includes an insertion portion 13 that is inserted into a subject, and an operation portion 14 that is connected to a proximal end portion of the insertion portion 13. The distal end portion 13a connected to the distal end of the insertion portion 13 is provided with an objective lens 15 for capturing image light of an observed site image in the subject, a CCD 16 for imaging the image light, an irradiation lens 17 and the inside of the subject. The LED 18 for illumination (both see FIG. 4) is incorporated. The image in the subject acquired by the CCD 16 is displayed as an endoscopic image on the monitor 19 connected to the processor device 11.

  A bending portion 13b connecting a plurality of bending pieces is provided behind the tip portion 13a. The bending portion 13b is bent in the vertical and horizontal directions when the angle knob 14a provided in the operation portion 14 is operated and a wire inserted in the insertion portion 13 is pushed and pulled. Thereby, the front-end | tip part 13a is orient | assigned to the desired direction in a subject.

  A flexible soft part 13c is provided behind the curved part 13b. In order to keep the distal end portion 13a reachable to the site to be observed and to keep the distance from the patient to the extent that the surgeon does not interfere with the operation portion 14 when operating it, It has a length of several meters.

  A cartridge 23 containing a water storage tank 21 in which water is stored and an air cylinder 22 in which air is stored is detachably attached below the operation unit 14. The water and air stored in the water storage tank 21 and the air cylinder 22 are linked to the operation of the water supply / air supply button 14b of the operation unit 14, and the water supply pipe and the air supply provided in the electronic endoscope 10 are operated. It is jetted toward the objective lens 15 through a pipe from a cleaning nozzle (not shown) formed at the tip 13a. As a result, it is possible to remove dirt attached to the surface of the objective lens 15 and to feed air into the subject. Here, the cartridge 23 is attached at a position where the base of the operator's hand abuts when the electronic endoscope 10 is used, and also plays a role of stabilizing the operability of the electronic endoscope 10. Reference numeral 24 denotes a forceps port through which the treatment tool is inserted.

  As shown in FIG. 2, the flexible portion 13 c is composed of an outer skin layer 30, a cylindrical net body 31, and flexible tubes 32 and 33. The outer skin layer 30 is formed by molding a soft resin, and has a smooth surface so as to be suitable when the soft portion 13c slides in the subject. The cylindrical net 31 is formed by braiding a wire made of an insulator such as an aramid fiber with a predetermined number and number of strikes, and is bonded to the outer skin layer 30 with an adhesive or the like.

  The flexible tubes 32 and 33 are arranged so as to overlap the outside and the inside. The flexible tubes 32 and 33 are formed by winding a band-shaped elastic metal having a predetermined width in a spiral shape at a predetermined pitch, and the directions of the spirals are opposite to each other. In particular, the flexible tube 33 is made of, for example, alumite-treated aluminum or heat-treated special stainless steel (product name KCF, manufactured by Nakano Hagane Co., Ltd., Internet URL <http://www.nakano-steel.co.jp/ kcf.html>). An oxide film 34 is formed on the surface of the flexible tube 33 by alumite treatment or heat treatment. The flexible tube 33 is electrically insulated from the flexible tube 32 by the oxide film 34.

  In FIG. 3, the tap 40 is connected to the flexible tube 32 at the lengths d1 to d3 from the end on the distal end portion 13a side. A capacitor 43 constituting a tuning circuit 42 of the transmitter 57 (see FIG. 4) is connected in parallel to the portion 32a of the length d1 to d3 of the flexible tube 32 via the tap 40 and the changeover switch 41. . The changeover switch 41 selectively switches the tap 40 connected to the capacitor 43 in conjunction with the operation of the hand switch 14 c of the operation unit 14. As a result, the length 32 to the length d <b> 3 of the flexible tube 32 function as an inductor of the tuning circuit 42, and the transmission frequency of the radio wave 12 is changed by selectively switching the tap 40 with the changeover switch 41. Is done. Note that the values of d1 to d3 are determined by the transmission frequency of the radio wave 12 and the capacity of the capacitor 43, and are values that give a certain range to the transmission frequency to be changed, such as 300 MHz, 350 MHz, and 400 MHz. Yes.

  An insulating ring 44 is disposed on the flexible tube 32 at a length d3 from the end on the distal end portion 13a side. In the flexible tube 32, the insulating ring 44 electrically isolates the portion 32a having the length d3 from the other portion 32b and mechanically connects them.

  In FIG. 4, the CPU 50 comprehensively controls the operation of the entire electronic endoscope 10. Connected to the CPU 50 is a ROM 51 that stores various programs and data for controlling the operation of the electronic endoscope 10. The CPU 50 reads out necessary programs and data from the ROM 51 and controls the operation of the electronic endoscope 10.

  Further, a timing generator (TG) 52 is connected to the CPU 50. The TG 52 is connected to the CCD 16, an AFE 54, which will be described later, and a parallel / serial conversion unit (P / S) 55, and transmits timing signals (clock pulses) to these units. The CCD 16, the AFE 54, and the P / S 55 operate based on the timing signal transmitted from the TG 52.

  A drive unit 53 is connected to the LED 18. The drive unit 53 drives the LED 18 on / off under the control of the CPU 50. Light emitted from the LED 18 is irradiated to an observation site in the subject through the irradiation lens 17. In addition, it is good also as a structure which arrange | positions LED18 inside the operation part 14 instead of the front-end | tip part 13a, and guides it to the front-end | tip part 13a with a light guide.

  The CCD 16 forms an image of the observation site incident from the objective lens 15 on the imaging surface, and outputs an imaging signal corresponding to the image light from each pixel. The AFE 54 performs correlated double sampling, amplification, and A / D conversion on the imaging signal input from the CCD 16 to convert the imaging signal into a digital image signal.

  The P / S 55 converts the digital image signal input from the AFE 54 from parallel data to serial data. The P / S 55 serially converts the vertical and horizontal synchronizing signals of the image signal based on the timing signal from the TG 52.

  The modulation unit 56 performs digital quadrature modulation on the serial data output from the P / S 55 using, for example, a four-value PSK (QPSK) method, and modulates the RF data representing the radio wave 12. The transmitter 57 feeds the antenna 58 with a high frequency current corresponding to the RF signal modulated by the modulator 56. As a result, the radio wave 12 is transmitted from the antenna 58 to the processor device 11.

  A battery 60 is connected to the connector 59. The power of the battery 60 is supplied to each part of the electronic endoscope 10 from a power supply unit 61 controlled by the CPU 50. Although not shown in FIG. 1, a battery storage chamber for storing the battery 60 is provided at the rear portion of the operation unit 14, and the connector 59 is disposed therein.

  In FIG. 5, the CPU 70 comprehensively controls the operation of the entire processor device 11. The CPU 70 is connected to a ROM 71 that stores various programs and data for controlling the operation of the processor device 11. The CPU 70 reads out necessary programs and data from the ROM 71 and controls the operation of the processor device 11.

  The antenna 72 receives the radio wave 12 from the antenna 58. The receiving unit 73 demodulates the radio wave 12 received by the antenna 72 into an RF signal and amplifies it. The receiving unit 73 is provided with a tuning circuit (not shown) similar to the tuning circuit 42, and the reception frequency of the radio wave 12 is tuned to the transmission frequency set by the tuning circuit 42.

  The demodulation unit 74 performs digital quadrature detection on the RF signal and demodulates the RF signal into an image signal before being modulated by the modulation unit 56. Under the control of the CPU 70, the synchronization separation unit 75 separates the synchronization signal from the image signal demodulated by the demodulation unit 74 by amplitude separation, and then separates the horizontal synchronization signal and the vertical synchronization signal by frequency separation.

  The image signal processing unit 76 generates a digital video signal from the image signal. The video signal processing unit 77 performs various image processing such as mask generation and character information addition on the video signal generated by the image signal processing unit 76. The buffer 78 temporarily stores a video signal that is subjected to various image processing by the video signal processing unit 77 and displayed as an endoscopic image on the monitor 19.

  When observing the inside of the subject with the electronic endoscope system 2 configured as described above, the insertion unit 13 is inserted into the subject, and the LED 16 is turned on to illuminate the inside of the subject. An endoscopic image is observed on the monitor 19.

  At this time, the image light of the observation site incident from the objective lens 15 is imaged on the imaging surface of the CCD 16, and an imaging signal is output from the CCD 16. The imaging signal output from the CCD 16 is subjected to correlated double sampling, amplification, and A / D conversion by the AFE 54, and is converted into a digital image signal.

  The digital image signal output from the AFE 54 is converted into serial data by the P / S 55. The serial data output from the P / S 55 is subjected to digital quadrature modulation by the modulation unit 56 and becomes an RF signal. The RF signal is tuned by the tuning circuit 42 using the portion 32a of the flexible tube 32 as an inductor in the transmission unit 57, and is transmitted as the radio wave 12 from the antenna 58 at the transmission frequency selected by the changeover switch 41.

  On the other hand, in the processor device 11, when the radio wave 12 transmitted from the antenna 58 is received by the antenna 72, the radio wave 12 is demodulated into an RF signal by the receiving unit 73 and amplified. In the demodulation unit 74, digital quadrature detection is performed on the RF signal amplified by the reception unit 73, and the RF signal is demodulated into an image signal before being modulated by the modulation unit 56.

  The image signal demodulated by the demodulator 74 is subjected to synchronization separation by the synchronization separation unit 75 under the control of the CPU 70. Then, the image signal processing unit 76 outputs the digital video signal. The video signal output from the image signal processing unit 76 is subjected to various types of image processing by the video signal processing unit 77, temporarily stored in the buffer 78, and displayed on the monitor 19 as an endoscopic image.

  As described above, since the portion 32a of the flexible tube 32 embedded in the flexible portion 13c is used as the inductor of the tuning circuit 42, the radio wave 12 can be reliably tuned. Further, the flexible tube 32 is an existing component in the electronic endoscope 10, and it is not necessary to separately provide an inductor, so that the component cost can be reduced.

  Since the tap 40 is connected to the portion 32a of the flexible tube 32 and is selectively switched by the changeover switch 41, when a plurality of electronic endoscopes 10 are used in a limited space such as an examination room. In addition, a dedicated channel of the radio wave 12 can be assigned to each electronic endoscope 10, and interference between devices can be prevented.

  In the above-described embodiment, the tap 40 is connected to the portion 32a of the flexible tube 32 and selectively switched by the changeover switch 41, so that the μ-tuning example of changing the transmission frequency of the radio wave 12 has been described. The present invention is not limited to this, and a variable capacitance capacitor 81 is used as a capacitor without providing the tap 40 in the portion 32a of the flexible tube 32 as in the tuning circuit 80 shown in FIG. A C-tuned type in which the transmission frequency of the radio wave 12 is changed by switching with a knob or the like provided in FIG.

  As the flexible tube 33, a metal having an insulating resin coated on the surface may be used instead of the metal having the oxide film 34 formed on the surface. In short, the portion 32a of the flexible tube 32 used as the inductor is electrically insulated from other members constituting the flexible portion 13c such as the cylindrical net 31 and the flexible tube 33 except for the wiring connected to the tuning circuit 42. The oxide film 34 may be formed on the surface of the portion 32a of the flexible tube 32 used as the inductor, or an insulating resin may be coated.

  In the above embodiment, the flexible tubes 32 and 33 having a double structure have been described as an example. However, the present invention can be applied to a case where the flexible tube is single. Further, the flexible portion 13c corresponding to the portion 32a of the flexible tube 32 used as the inductor is detachably unitized with other portions, and the unitized portion is replaced according to the transmission / reception frequency of the radio wave 12. Also good.

It is the schematic which shows the structure of an electronic endoscope system. It is the schematic which shows the structure of a soft part. It is explanatory drawing which shows typically a mode that the flexible tube was used as an inductor of a tuning circuit. It is a block diagram which shows the structure of an electronic endoscope. It is a block diagram which shows the structure of a processor apparatus. It is explanatory drawing which shows another embodiment.

Explanation of symbols

2 Electronic Endoscope System 10 Electronic Endoscope 11 Processor Device 12 Radio Wave 13 Insertion Unit 13c Soft Part 19 Monitor 32, 33 Flexible Tube 42, 80 Tuning Circuit 43 Capacitor 50 CPU
56 Modulator 57 Transmitter 70 CPU
73 Receiver 74 Demodulator 81 Capacitance variable capacitor

Claims (5)

In an electronic endoscope that acquires an image of an observation site of a subject and transmits a signal representing the image to a processor device by radio waves,
A spirally wound metal flexible tube that forms a flexible portion of the insertion portion to be inserted into the subject;
Using at least a portion of the flexible tube as an inductor of a tuning circuit for transmitting the radio wave at a specific frequency ;
An electronic endoscope characterized in that a portion of the flexible tube used as the inductor is electrically insulated from other members constituting the flexible portion excluding wiring connected to the tuning circuit . The electronic endoscope according to claim 1, wherein the portion of the flexible tube used as the inductor and the other portion are connected by an insulating ring. Connecting a plurality of taps to the portion of the flexible tube used as the inductor;
The connections to multiple taps in selectively switching the electronic endoscope according to claim 1 or 2, characterized by providing the first switching means for changing the frequency. The capacitor of the tuning circuit connected in parallel to the inductor is a variable capacitance capacitor,
The capacity variable capacitance of the capacitor is selectively switching the electronic endoscope according to claim 1 or 2, characterized by providing a second switching means for changing the frequency. Two flexible tubes with opposite spiral directions are arranged on the outside and inside,
5. The electronic endoscope according to claim 1, wherein one flexible tube is used as the inductor and is electrically insulated from the other flexible tube.

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