JP2011083454A - Electronic endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress influence of cable loss and EMC in an electronic endoscope by shortening substantial power transmission distance. <P>SOLUTION: An imaging element 23 is mounted on a distal end 11A of an insertion unit of an endoscope. A relay unit 26 is mounted on an operation unit of the endoscope. A dividing circuit 28 and a second power supply circuit 29 working as a switching regulator are arranged in the relay unit 26. An imaging element driving signal is divided by the dividing circuit 28 and is outputted to the second power supply circuit 29 as a reference clock signal. The second power supply circuit 29 generates power supply for driving the imaging element 23 from power supplied from an endoscope proximal unit 13 via a first power supply transmission pathway 30, and supplies the power supply to the imaging element 23 via a second power supply transmission pathway 31. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electronic endoscope apparatus in which a scope main body and a processor device that performs main video signal processing are provided separately from each other.

  In an electronic endoscope, a video signal from an image sensor provided at the distal end of an insertion portion is sent to a camera control unit (processor device) connected to a scope base end portion, subjected to predetermined video signal processing, and then monitored. To display. Since the space at the distal end of the insertion portion is extremely limited, the drive circuit for driving the image sensor and the main device for processing the video signal are suitable for the processor device and the appropriate location on the base end side of the scope (to the processor device). Such as an endoscope base including a connector for connection. For this reason, the drive signal is sent to the image sensor through a signal cable connecting the distal end of the insertion portion and the processor device, and the obtained video analog signal is also sent to the processor device and the scope base end portion via the signal cable. It is sent to a front end circuit or the like (Patent Document 1).

JP 2000-342531 A

  For example, in a medical electronic endoscope, electric power is supplied from the processor device side to the imaging device, and therefore, a power transmission path is provided over several meters from the endoscope base to the endoscope distal end. For this reason, a decrease in power supply voltage due to cable loss, a problem of EMC in which the power transmission path becomes an antenna, and the like occur.

  An object of the present invention is to shorten a substantial power transmission distance in an electronic endoscope apparatus and suppress the influence of cable loss and EMC.

  An electronic endoscope according to the present invention includes an insertion portion in which an imaging element is provided at a distal end portion, an operation portion provided at a proximal end portion of the insertion portion, an endoscope base portion including a connector coupled to a processor device, An electronic endoscope having a universal cord that communicates between the head portion and the endoscope base portion, wherein the relay portion is disposed from the proximal end portion than the insertion portion and from the distal end portion than the endoscope base portion. The relay unit is provided with a power supply circuit that is supplied with power from the endoscope base side via the first power transmission path and applies a power supply voltage to the image sensor via the second power transmission path, and The element drive signal is used as an output enable signal of the power supply circuit.

  For example, the relay unit is provided in the operation unit. It is preferable that the relay unit includes a frequency dividing circuit that divides the imaging element driving signal, the power supply circuit is a switching regulator, and an output from the frequency dividing circuit is used as a reference clock signal for the switching regulator.

  According to the present invention, in the electronic endoscope apparatus, a substantial power transmission distance can be shortened, and the influence of cable loss and EMC can be suppressed.

1 is a schematic external view showing a configuration of an electronic endoscope (scope body) that is an embodiment of the present invention. It is a block diagram which shows typically the electric constitution of the scope main body of this embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic external view showing the configuration of the electronic endoscope according to the first embodiment of the present invention.

  The electronic endoscope system includes a scope main body (electronic endoscope) 10 and a processor device (not shown) that is connected to the scope main body 10 and performs various types of image processing and supplies illumination light to the scope main body 10. It is generally composed of a monitor device (not shown) that is connected to the processor device and displays an image taken by the scope body 10. FIG. 1 shows an appearance of a scope body (electronic endoscope) 10.

  The scope body 10 includes a flexible tubular insertion portion 11 to be inserted into a body or a tube hole, an operation portion 12 provided at a proximal end portion of the insertion portion 11 and held and operated by a user, It is comprised from the endoscope base 13 for connecting the operation part 12 to a processor apparatus (not shown), and the universal cord 14 which connects between the operation part 12 and the endoscope base 13. As is well known in the art, an imaging element (see FIG. 2) is provided at the distal end portion 11A of the insertion portion 11, and an image of the subject is captured by the imaging element with illumination light emitted from the distal end portion 11A. The illumination light is normally supplied from the processor device through a light guide disposed in the scope body 10.

  FIG. 2 is a block diagram schematically showing an electrical configuration of the scope main body 10 shown in FIG. Although not shown, the optical configuration related to the illumination light is, for example, a conventionally well-known one using a light guide. In the case of this embodiment, an insertion portion is inserted from the light source provided in the processor device via the light guide. The light is transmitted to 11 tip portions 11A. However, a configuration in which a separate light source device is provided outside the processor device or a configuration in which a light source such as an LED is provided at the distal end portion 11A and illumination light is directly irradiated can be employed.

  The endoscope base 13 of the present embodiment includes, for example, an I / O port 15, a control circuit 16, a system clock generator 17, a signal processing circuit (DSP) 18, a first power supply circuit 19, a sensor clock transmission driver 21, An analog front end 22 and the like are provided. The endoscope base 13 is electrically connected to a processor device (not shown) via an I / O port 15 including a connector. A control circuit 16, a system clock generator 17, a signal processing circuit (DSP) 18, a first power supply circuit 19 and the like are connected to the I / O port 15.

  The control circuit 16 controls the scope body 10 as a whole, and exchanges data with each device as necessary. The system clock generator 17 generates various clock signals required in the scope body 10. For example, a necessary signal is output from the system clock generator 17 to the drive circuit 21 and the signal processing circuit (DSP) 18.

  An imaging element 23 such as a CCD or CMOS is provided at the distal end portion 11A of the insertion portion 11 (see FIG. 1). The image sensor 23 is driven by an image sensor drive signal (V drive signal or H drive signal) output from a drive circuit 21 provided in the endoscope base 13, and the image sensor drive signal passes through the sensor clock transmission path 27. Via the image sensor 23.

  The subject image is captured by the image sensor 23 via the imaging lens 24. The imaging device 23 is connected to an analog front end (AFE) 22 provided in the endoscope base 13 through a signal cable (video signal transmission path) 25 wired through the insertion unit 11, the operation unit 12, and the universal cord 14. The analog video signal from the image pickup device 23 is sent to the signal processing circuit 18 via the analog front end 22, subjected to predetermined image processing, and then to the processor device via the I / O port 15. Sent out.

  The analog front end 22 includes, for example, a first-stage amplifier circuit, a correlated double sampling circuit, and an AD converter. The analog video signal from the video signal transmission path 25 is amplified with a predetermined gain by the first-stage amplifier circuit and then correlated. The signal is sampled in the double sampling circuit, converted into a digital video signal in the AD converter, and sent to the signal processing circuit 18.

  Further, the scope main body 10 of the first embodiment includes a relay unit 26 between the distal end portion 11A and the endoscope base unit 13, for example, the operation unit 12 (see FIG. 1). The relay unit 26 is provided with a frequency dividing circuit 28 and a second power supply circuit 29. The frequency dividing circuit 28 is connected to the sensor clock transmission path 27 and receives an image sensor driving signal output from the drive circuit 21. In the frequency divider circuit 28, frequency division is performed at a predetermined ratio with respect to the image sensor drive signal, and the frequency is output to the second power supply circuit 29.

  The second power supply circuit 29 is, for example, a switch regulator, and is supplied with power from the first power supply circuit 19 provided in the endoscope base 13 via the first power transmission path 30 and is supplied from the frequency dividing circuit 28. For example, a power supply voltage for the image sensor 23 is generated based on the signal (reference clock signal). The power supply voltage generated in the second power supply circuit 29 is transmitted to the insertion portion distal end 11 </ b> A through the second power supply transmission path 31 and applied to the power supply terminal of the image sensor 23. The voltage output from the first power supply circuit 19 is, for example, + 5V, and the power supply voltage output from the second power supply circuit 29 is, for example, ± 15V. Further, the second power supply circuit may be configured to further supply power of different voltages to other circuits provided in the operation unit 12 and the distal end portion 11A.

  As described above, according to the present embodiment, since the power line is relayed at the relay unit, the substantial power transmission distance is shortened, and the cable loss can be reduced. In addition, the portion that becomes an antenna with respect to disturbance is shortened, and the influence of EMC can be suppressed.

  Furthermore, in this embodiment, since the image sensor driving signal is used as the output enable signal of the power supply, the power supply to the image sensor can be stopped when the driving signal is not output. In addition, since the image sensor driving signal is used as a reference clock for the second power supply circuit (switching regulator), the number of elements in the relay unit can be reduced. In this embodiment, a switching regulator is used for the second power supply circuit, and the image sensor driving signal is used as a reference clock signal. However, the image sensor driving signal (presence) is simply used as an output enable signal of the power source. You can also.

  In the present embodiment, the relay unit is provided in the operation unit of the scope main body. However, as the installation location of the relay unit, for example, in a position where it is not actually inserted into the body (a position closer to the base end than the insertion unit). A location closer to the tip than the endoscope base is selected. Moreover, it is preferable that the housing | casing which accommodates the circuit installed in a relay part is equipped with the structure which directly heat-radiates from the device package on a circuit board to a housing | casing. Further, it is possible to provide an EMC countermeasure filter in the power supply circuit of the relay unit.

10 Scope body (electronic endoscope)
DESCRIPTION OF SYMBOLS 11 Insertion part 11A Tip part 12 Operation part 13 Endoscope base 14 Universal cord 19 1st power supply circuit 21 Drive circuit 22 Analog front end (AFE)
DESCRIPTION OF SYMBOLS 23 Image pick-up element 26 Relay part 27 Sensor clock transmission path 28 Frequency dividing circuit 29 2nd power supply circuit 30 1st power supply transmission path 31 2nd power supply transmission path

Claims (3)

An insertion portion provided with an imaging element at a distal end portion, an operation portion provided at a proximal end portion of the insertion portion, an endoscope base portion including a connector coupled to a processor device, the operation portion, and the endoscope base portion An electronic endoscope having a universal code for communicating with
A relay portion disposed from the proximal end portion than the insertion portion and from the distal end portion than the endoscope base portion;
The relay unit is provided with a power supply circuit that is supplied with power from the endoscope base side via the first power transmission path and applies a power supply voltage to the imaging element via the second power transmission path, An electronic endoscope, wherein an image sensor driving signal is used as an output enable signal of the power supply circuit.   The electronic endoscope according to claim 1, wherein the relay unit is provided in the operation unit.   The relay unit includes a frequency dividing circuit that divides the imaging element driving signal, the power supply circuit is a switching regulator, and an output from the frequency dividing circuit is used as a reference clock signal for the switching regulator. The electronic endoscope according to claim 2, characterized in that:

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