JP2013013494A - Electronic endoscope device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic endoscope device capable of achieving excellent EMC(electro-magnetic compatibility) without forming a core in the inside of a processor.SOLUTION: A processor 20 to which a video scope 10 is connected includes buffer circuits 22, 24 on the side of a connector 20C serving as a scope connecting portion. In a state where the video scope 10 is connected to the processor, a maximum power supply voltage Vm is supplied to the buffer circuits 22, 24 via a DC/DC converter 36. When the video scope 10 is disconnected, a minimum power supply voltage Vz is supplied to the buffer circuits 22, 24.

Description

  The present invention relates to an electronic endoscope apparatus that images a subject such as an inner wall of an organ using a video scope and displays an observation image on a monitor, and more particularly, electromagnetic wave noise emitted through a connector (connector) between a scope and a processor. Related to the shield.

  In an electronic endoscope apparatus, a video scope having an image sensor such as a CCD is connected to a processor that performs image processing and the like so that the video endoscope and the processor are driven. Signals, control signals, image signals, data signals, etc. are transmitted. Therefore, electromagnetic noise is likely to be emitted through the connector of the scope and the processor.

  Since the electronic endoscope apparatus is a medical device, it is strongly required to shield electromagnetic wave noise emission. That is, excellent EMC (Electro-Magnetic Compatibility) is required. In particular, it is necessary to sufficiently suppress noise emission from the connector portion of the processor even when the video scope is disconnected when the processor is powered on.

  A cylindrical core made of a magnetic material may be used as a member that blocks electromagnetic noise emission. Since the videoscope and processor have a structure in which connectors such as plugs and receptacles are in direct contact with each other, a configuration in which a core is provided near the connection of a signal cable for connection as in a computer system is not adopted. A core is provided (see Patent Document 1).

JP 2003-204931 A

  In the vicinity of the connector of the video scope and the processor, parts such as a circuit mechanism, a light source device, and a light guide mechanism are densely packed and space is limited. It is difficult to insert the core into this dense part. In particular, the heat from the light source device arranged near the connector is likely to concentrate on the dense portion, and the arrangement of the core may destabilize the operation of the processor.

  Therefore, it is necessary to be able to provide a high EMC sufficiently, regardless of whether the videoscope is connected or disconnected, without providing an electromagnetic shield member such as a core.

  An endoscope apparatus according to the present invention includes a processor connector (herein referred to as a processor side connector) connected to a video scope connector (herein referred to as a scope side connector), and a buffer circuit connected to the processor side connector through wiring. And a power supply voltage control means for adjusting a power supply voltage (drive voltage) supplied to the buffer circuit, and a scope connection detection means for detecting connection / removal of the videoscope.

  The scope side connector and the processor side connector can be configured by, for example, a plug, a receptacle, etc., respectively, and the electrical connection (signal transmission, power supply, etc.) between the video scope and the processor is realized by directly connecting to each other. The

  A buffer circuit that can operate as a buffer circuit is a circuit that is connected to a processor side connector through wiring, and when configured as an input side buffer circuit, a circuit (image signal, data, etc.) from the scope side is input first. It becomes. On the other hand, when functioning as an output side buffer circuit, a signal (drive signal, control signal, power supply voltage signal, etc.) sent to the scope side is finally input / output immediately before the connector.

  Regarding the configuration of the power supply voltage control means, for example, a DC / DC converter that converts a DC power supply and supplies a predetermined drive voltage to the buffer circuit, and a converter voltage control circuit that controls the drive voltage supplied to the DC / DC converter. Can be provided. As the drive voltage of the converter changes, the supply voltage to the buffer circuit changes.

  Then, when the removal of the videoscope is detected, the power supply voltage control means of the present invention lowers the power supply voltage to the buffer circuit compared to the power supply voltage when the videoscope is connected. Due to the power supply voltage drop, electromagnetic noise emission from the buffer circuit closest to the processor side connector is suppressed.

  The amplitude of the electromagnetic noise depends on the level of the power supply voltage of the buffer circuit. When the drive voltage of the buffer circuit is lowered, the electromagnetic noise emission during the operation is also reduced. As a result, the electromagnetic noise emitted to the outside from the processor-side connector is automatically suppressed as the videoscope is removed. That is, the emission of electromagnetic noise can be suppressed without providing a member such as a core between the connector and the buffer circuit.

  The power supply voltage control means may reduce the power supply voltage supplied to the buffer circuit while the videoscope is detached. When connection of the video scope is detected again, the power supply voltage to the buffer circuit returns to the power supply voltage when the video scope is connected.

  The power supply voltage control means can appropriately set the drive voltage within the voltage range in which the buffer circuit can operate. During videoscope connection, the maximum voltage can be set within the operable drive voltage range in order to fully function as a buffer circuit. On the other hand, when the video scope is not connected, noise emission can be suppressed to the maximum by setting the minimum voltage.

  In the case of a buffer circuit to which an image signal is first input, if the drive voltage to the buffer circuit is lowered immediately after removal of the video scope, the video signal is disturbed due to the voltage change, and the image is disturbed on the monitor. In order to prevent this, it is preferable that the power supply voltage control means first outputs a reset signal to the buffer circuit to stop video output, and then lowers the power supply voltage supplied to the buffer circuit.

  A buffer circuit can be provided near a signal output connector such as a video signal output terminal of the processor. For example, a buffer circuit is provided immediately before an output terminal to which a signal cable capable of transmitting a video signal is connected. In this case, it is desirable to adjust the power supply voltage (drive voltage) supplied to the buffer circuit as in the buffer circuit provided in the vicinity of the video scope connection connector.

  For example, external device connection detection means for detecting connection of an external device to the video signal output unit of the processor is provided, and the power supply voltage control means supplies power to the external device buffer circuit when removal of the external device is detected. Reduce the voltage compared to the power supply voltage when an external device is connected.

  An endoscope power supply voltage control device according to the present invention includes a power supply voltage control means for adjusting a power supply voltage supplied to a buffer circuit connected through a wiring to a processor side connector connected to a scope side connector of a videoscope, and a videoscope Scope connection detection means for detecting connection / disconnection, and when the power supply voltage control means detects removal of the videoscope, the power supply voltage supplied to the buffer circuit is lower than the power supply voltage when the videoscope is connected. It is characterized by making it.

  The program of the present invention includes a power supply voltage control means for adjusting a power supply voltage supplied to a buffer circuit connected through wiring to a processor side connector for connecting an electronic endoscope apparatus to a scope side connector of a videoscope, and a videoscope A program that functions as a scope connection detection unit that detects connection / disconnection, and when the removal of the videoscope is detected, the power supply voltage supplied to the buffer circuit is reduced compared to the power supply voltage when the videoscope is connected. To function as power supply voltage control means.

  As described above, according to the present invention, an excellent EMC can be realized without providing a core inside the processor.

It is a block diagram of the electronic endoscope apparatus which is this embodiment. It is a schematic block diagram of a buffer circuit. It is the flowchart which showed the drive voltage control process of the input side buffer circuit performed by a system control circuit. It is a timing chart of a drive voltage control process. It is a flowchart of the drive voltage control process with respect to a video signal output side buffer circuit.

  Hereinafter, the electronic endoscope apparatus according to the present embodiment will be described with reference to the drawings.

  FIG. 1 is a block diagram of an electronic endoscope apparatus according to this embodiment.

  The electronic endoscope apparatus includes a video scope 10 provided with an image sensor 12 at a distal end thereof, and a processor 20, and the video scope 10 is detachably connected to the processor 20. A monitor 50 is connected to the processor 20.

  The processor 20 includes a light source device 30 such as a xenon lamp, and illumination light emitted from the light source device 30 is incident on a light guide 11 provided in the video scope 10 via a condenser lens (not shown). Is incident on the subject (observation target) from the scope tip 10B through the light guide 11. A diaphragm (not shown) is provided between the light source device 30 and the light guide 11, and the amount of light is automatically adjusted by opening and closing the diaphragm.

  The illumination light reflected by the subject is imaged by an objective lens (not shown) provided at the scope tip 10B, and the subject image is formed on the light receiving surface of the image sensor 12, such as a CCD. In the image sensor 12, pixel signals for one frame are read from the image sensor 12 at predetermined frame time intervals (eg, 1/30 second intervals). The image sensor 12 is provided with a complementary color filter in which color elements composed of Cy, Ye, G, Mg or R, G, B are arranged in a mosaic pattern.

  The read series of pixel signals are digitized by the pre-stage image signal processing circuit 14 and image signal processing such as white balance processing and gamma correction processing is performed on the digitized pixel signals. As a result, R, G, and B image signals are generated. The generated R, G, B image signals are sent to the processor 20 through the buffer circuit 17.

  The image signal transmitted to the processor 20 is transmitted to the subsequent image processing circuit 28 via the buffer circuit 32. In the post-stage image processing circuit 28, outline enhancement processing, superimposition processing, and the like are performed on the image signal. Then, the image signal is output as a video signal to the monitor 50, whereby the observation image is displayed on the monitor 50 in real time.

  A system control circuit 25 including a CPU, a RAM, and the like outputs a control signal to the subsequent image signal processing circuit 28 and the like, and controls the entire operation when the processor 20 is in a power-on state. The operation control program is stored in the ROM 26 in advance.

  When the video scope 10 is connected to the processor 20, the system control circuit 25 communicates with the scope controller 16 via the buffer circuits 19 and 22 and acquires data relating to the scope characteristics (resolution, scope type) stored in the ROM 18. To do. Further, the system control circuit 25 outputs a drive signal to a CCD drive circuit (not shown) provided in the scope controller 16. The scope controller 16 performs scope operation control based on color information data and the like sent from the processor 20.

  The power supply unit 34 converts AC power into DC power and supplies power to the processor 20 and further to the electric circuit of the video scope 10 through the DC / DC converter 36. The converter voltage control circuit 38 supplies a drive voltage to the DC / DC converter 36 and adjusts the value of the drive voltage for the DC / DC converter 36 based on a control signal from the system control circuit 25.

  The video scope 10 is formed with a plug-shaped connector 10C, and the processor 20 is formed with a receptacle-shaped connector 20C. The connector 10C and the connector 20C are directly coupled to each other, whereby electrical connection between the video scope 10 and the processor 20 is achieved. Connection is realized. That is, a series of signals such as a drive signal, a control signal, a power supply voltage signal, and an image signal can be transmitted between the video scope 10 and the processor 20.

  The buffer circuit 24 to which R, G, and B image signals are input is connected to the connector 20C through the wiring 21A. Here, the buffer circuit 24 is a buffer circuit constituted by a buffer IC (Integrated Circuit). In order to prevent the buffer circuit 24 from being affected by the operation of the preceding circuit, that is, the video scope side circuit, the image signal is first buffered. 24.

  Another buffer circuit 22 provided in the vicinity of the connector 20C is a buffer circuit provided between the system control circuit 25 and the connector 20C, and a drive signal, control signal, and data sent from the system control circuit 25. The signal and the power supply voltage signal pass through the buffer circuit 22 and are output from the connector 20C through the wiring 21B. Therefore, it functions as an output side buffer circuit.

  On the other hand, a control signal or data signal sent from the scope controller 16 is first input to the buffer circuit 22 through the wiring 21B. Therefore, the buffer circuit 22 functions as a buffer circuit on both the input side and the output side.

  The processor 20 is provided with a connector 20D having a video signal output terminal on the side opposite to the connector 20C. A buffer circuit 32 is connected to the connector 20D through a wiring 32A. The video signal output from the post-stage image signal processing circuit 28 finally passes through the buffer circuit 32 and is output to an external device such as the monitor 50.

  Thus, the buffer circuits 22, 24, and 32 of the processor 20 are directly connected to the connectors 10C, 20C, and 20D through the wirings 21A, 21B, and 32A, and the signal input / output is the first / last circuit. The internal configuration of this buffer circuit will be described below.

  FIG. 2 is a schematic block diagram of the buffer circuit 24.

  The buffer circuit 24 is configured by a buffer IC 24A, and a power supply voltage is supplied as a drive voltage by a DC / DC converter 36. The DC / DC converter 36 reduces the voltage of the DC power supply to a voltage range (voltage band) in which the buffer IC 24A can operate.

  The converter voltage control circuit 38 operates by supplying power from the power supply unit 34 and supplies a drive voltage to the DC / DC converter 36. The converter voltage control circuit 38 can operate the DC / DC converter 36 with different drive voltages, and the power supply voltage supplied from the DC / DC converter 36 to the buffer circuit 24 is applied to the DC / DC converter 36. It changes according to the value of the driving voltage.

  The system control circuit 25 can output a control signal to the converter voltage control circuit 38 and adjust the drive voltage for the DC / DC converter 36. Therefore, the power supply voltage to the buffer circuit 24 is adjusted according to the control signal sent from the system control circuit 25 to the converter voltage control circuit 38.

  Similarly, the drive voltages of the other buffer circuits 22 and 32 are adjusted by the DC / DC converter 36 and the converter voltage control circuit 38. However, since a plurality of signals such as a drive signal, a control signal, and a data signal are input and output in the buffer circuit 22, buffer ICs are provided according to the number of signal lines.

  As described above, the buffer circuits 22, 24, and 32 are the first circuit on the input side or the last circuit on the output side of the processor 20, respectively, and electromagnetic noise is emitted from the connectors 20C and 20D to the outside through these buffer circuits. In this embodiment, operation control of an electric circuit capable of suppressing emission of electromagnetic noise is performed without providing a shield member such as a core. Hereinafter, circuit operation control in the buffer circuit 24 will be described.

  FIG. 3 is a flowchart showing a drive voltage control process of the buffer circuit 24 executed by the system control circuit 25. FIG. 4 is a timing chart of the drive voltage control process.

  While the power of the processor 20 is ON, it is detected whether or not the video scope 10 is connected to the processor 20 (S101). Here, the connection / disconnection of the video scope 10 is detected by pin bonding.

  If it is determined that the video scope 10 is connected, a control signal is sent to the converter voltage control circuit 38 so that the drive voltage for the DC / DC converter 36 is set to V0 (for example, 5V) (S102). As a result, the buffer IC 24A operates with the drive voltage (power supply voltage) Vm supplied from the DC / DC converter 36 (see FIG. 4). The drive voltage Vm is the maximum voltage in the voltage range R in which the buffer IC 24A can operate. Further, the reset signal for stopping the video signal is not sent to the buffer circuit 24 (S103).

  On the other hand, if it is determined that the video scope 10 has been removed, first, a reset signal for stopping video signal output is sent to the buffer circuit 24 (S104). The image signal is blacked out by the reset signal, and the output of the video signal to the monitor 50 is stopped. After the reset signal is output, in order to change the drive voltage of the buffer IC 24A from Vm to Vz, the control signal is converted to the converter voltage so that the drive voltage of the DC / DC converter 36 is set to V1 (eg, 3.3V). It is sent to the circuit 38 (S105). The drive voltage Vz is the minimum voltage in the operable voltage range R.

  The amplitude of the electromagnetic wave noise emitted from the buffer circuit 24 varies depending on the level of the drive voltage supplied to the buffer circuit 24. The smaller the drive voltage, the smaller the noise amplitude. Therefore, while the buffer circuit 24 is operated by the drive voltage Vz, the electromagnetic wave noise emitted becomes small. Further, since the drive voltage of the buffer circuit 24 is lowered after the output of the video signal is stopped, it is possible to prevent an image in which noise generated when the drive voltage is changed from being disturbed on the image signal is displayed.

  When the video scope 10 is connected to the processor 20 again, first, the drive voltage of the DC / DC converter 36 is changed from V1 to V0. As a result, the drive voltage of the buffer circuit 24 returns to Vm. Further, the reset signal is canceled and the video signal is sent to the monitor 50 (S102, S103).

  Similarly, the drive voltage of the buffer circuit 22 is controlled. That is, while the video scope 10 is detached, the buffer circuit 22 is supplied with the power supply voltage Vz. However, reset signal output control is not performed.

  Next, a drive voltage control process for the buffer circuit 32 provided near the connector 20D on the video signal output terminal side will be described with reference to FIG. FIG. 5 is a flowchart of the drive voltage control process for the buffer circuit 32.

  While the processor power is on, it is determined whether an external device such as a monitor is connected to the processor 20 through a cable (S201). Here, the connection is detected when the cable is inserted into the output terminal of the connector 20D.

  While the external device is connected, the drive voltage of the buffer circuit 32 is set to Vm (S203). On the other hand, when the external device is not connected, the drive voltage of the buffer circuit 32 is set to Vz (S202). Thereby, noise emission from the buffer circuit 32 is reduced.

  As described above, according to the present embodiment, the buffer circuits 22 and 24 are provided on the connector 20C side of the processor 20, and when the video scope 10 is connected to the processor, the buffer circuit 22 is passed through the DC / DC converter 36. , 24 is supplied with the maximum power supply voltage Vm. When the video scope 10 is removed, the minimum power supply voltage Vz is supplied to the buffer circuits 22 and 24.

  By controlling the driving voltage for such a buffer circuit, it is possible to suppress the emission of electromagnetic noise during removal of the video scope without providing a core for the buffer circuits 22 and 24 and the connector 20C or the buffer circuit 32 and the connector 20D. . As a result, the EMC required for the medical device can be sufficiently satisfied.

  In particular, various components such as a light source device and a condensing optical system are concentrated on the connector serving as a connection portion with the video scope, and space is limited. In this embodiment, since it is not necessary to provide a core in that portion, there is a margin in space, and heat from the light source device does not spread near the connector, and heat is dissipated to increase the temperature of the entire processor. It becomes possible to suppress.

  In addition, a shield member that absorbs noise, such as a core, is very expensive due to its material and is heavy. By eliminating such a shield member, a simple, inexpensive and lightweight processor can be realized.

  In the present embodiment, the core is not provided in the processor at all. However, the core may be provided in an area having a sufficient internal space other than between the buffer circuit and the connector described above. In this case, the external emission of noise can be suppressed completely.

  In addition, the drive voltage control is not particularly performed on the buffer circuit on the video signal output side, and only the drive voltage control on the buffer circuit on the scope connection side may be performed. By suppressing electromagnetic radiation noise on the scope connection side that affects the human body, it is possible to satisfy EMC as a medical device.

DESCRIPTION OF SYMBOLS 10 Videoscope 10C Connector 20 Processor 20C Connector 20D Connector 22 Buffer circuit 24 Buffer circuit 25 System control circuit 32 Buffer circuit 36 DC / DC converter 38 Converter voltage control circuit

Claims (10)

A processor side connector to be connected to the scope side connector of the video scope;
A buffer circuit connected to the processor-side connector through wiring;
Power supply voltage control means for adjusting the power supply voltage supplied to the buffer circuit;
Scope connection detection means for detecting connection / detachment of the video scope,
The electronic endoscope apparatus, wherein when the videoscope is detected to be detached, the power supply voltage control means lowers the power supply voltage supplied to the buffer circuit as compared with the power supply voltage when the videoscope is connected. Processor.   The electronic endoscope apparatus according to claim 1, wherein the power supply voltage control unit reduces the power supply voltage supplied to the buffer circuit while the videoscope is detached.   3. The processor of the electronic endoscope apparatus according to claim 1, wherein the buffer circuit is a buffer circuit to which an image signal from the videoscope is first input on the processor side.   4. The electronic endoscope apparatus according to claim 3, wherein the power supply voltage control means lowers a power supply voltage supplied to the buffer circuit after outputting a reset signal to the buffer circuit to stop video output. Processor.   3. The processor of an electronic endoscope apparatus according to claim 1, wherein the buffer circuit is a buffer circuit to which a drive signal or a control signal to be sent to the video scope is input or output.   6. The power supply voltage control means according to claim 1, wherein when the videoscope is detached, the power supply voltage control means supplies the lowest voltage as a power supply voltage within a voltage range in which the buffer circuit can operate. The processor of the electronic endoscope apparatus as described. The power supply voltage control means is
A DC / DC converter that converts a voltage of a DC power source and supplies a predetermined drive voltage to the buffer circuit;
A processor of an electronic endoscope apparatus according to claim 1, further comprising: a converter voltage control circuit that controls a drive voltage supplied to the DC / DC converter. A video signal output unit to which a signal cable capable of transmitting video signals is connected;
An external device buffer circuit connected to the video signal output unit through wiring;
An external device connection detecting means for detecting that the external device is connected to the video signal output unit;
2. The power supply voltage control means, when the removal of the external device is detected, reduces the power supply voltage supplied to the external device buffer circuit as compared with the power supply voltage when the external device is connected. The processor of the electronic endoscope apparatus in any one of thru | or 6. Power supply voltage control means for adjusting the power supply voltage supplied to the processor side connector connected to the scope side connector of the video scope and the buffer circuit connected through wiring;
Scope connection detection means for detecting connection / detachment of the video scope,
The power supply for an endoscope, wherein when the videoscope is detected to be detached, the power supply voltage control means lowers the power supply voltage supplied to the buffer circuit as compared with the power supply voltage when the videoscope is connected. Voltage control device. Electronic endoscope device
Power supply voltage control means for adjusting the power supply voltage supplied to the processor side connector connected to the scope side connector of the video scope and the buffer circuit connected through wiring;
A program for functioning as scope connection detection means for detecting connection / disconnection of the video scope,
When the removal of the videoscope is detected, the program functions as the power supply voltage control means so as to lower the power supply voltage supplied to the buffer circuit as compared with the power supply voltage when the videoscope is connected. .

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