Patent Publication Number: US-2016220095-A1

Title: Processor device for endoscope, endoscope system, and contactless power supply method for endoscope system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2015-019000, filed on Feb. 3, 2015. The above application(s) is hereby expressly incorporated by reference, in its entirety, into the present application. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a processor device for an endoscope, an endoscope system, and a contactless power supply method for an endoscope system, and particularly, to the technique of supplying power in a contactless manner to an endoscope. 
     2. Description of the Related Art 
     Endoscope systems are constituted of an imaging unit, such as a charge coupled device (CCD) image sensor, which images the inside of a body cavity, an endoscope including a connector section provided at an end of the universal cord, a connector section on which the connector section of the endoscope is detachably mounted, a control unit that performs image processing or the like on image signals output from the endoscope, and a processor device for an endoscope including a light source. 
     In the endoscope systems, supply of power from the processor device for an endoscope to the endoscope, and transmission of image signals and control signals between the processor device for an endoscope and the endoscope are performed by connecting the connector section of the endoscope, and the connector section of the processor device for an endoscope by electrical contacts. 
     In the endoscope systems, it is necessary to perform cleaning or disinfection of the endoscope after use. Therefore, it is necessary to attach a waterproofing cap that protects the electrical contacts to the connector section of the endoscope. However, not only is substantial time and effort required for attachment and detachment of the waterproofing cap, but also there is a problem that the electrical contacts may be damaged when attachment of the waterproofing cap is forgotten. 
     In order to cope with such problems, an endoscope system described in JP2013-208187A makes the connector section of the endoscope a waterproof structure, provides a communication unit that performs short-distance radio communication of image signals between the endoscope and the processor device for an endoscope, and provides a power supply unit that supplies power in a contactless manner from the processor device for an endoscope to the endoscope. 
     Additionally, the processor device for an endoscope described in JP2013-208187A is provided with a connector support part that detachably supports the connector section of the endoscope, a locking mechanism that performs switching between a locked state in which a support state of the connector section by the connector support part is held and an unlocked state where holding is released, and a short-distance contactless power transmission control unit that enables power supply of power in a contactless manner from a power supply unit when the locking mechanism is in the locked state and disables supply of power when the locking mechanism is in the unlocked state. Accordingly, the processor device for an endoscope can supply power in a contactless manner only when the connector section of the endoscope is mounted on the connector support part of the processor device for an endoscope. 
     SUMMARY OF THE INVENTION 
     Meanwhile, the processor device for an endoscope is unable to immediately ascertain the power situation of the endoscope when power is supplied in a contactless manner from the processor device for an endoscope to the endoscope, and there is a problem in that power becomes insufficient or excessive due to the load of the endoscope when constant power is supplied. 
     The invention has been made in view of such circumstances, and an object thereof is to provide a processor device for an endoscope, an endoscope system, and a contactless power supply method for an endoscope system that can excellently perform contactless supply of power to the endoscope. 
     In order to achieve the above object, a processor device for an endoscope according to an aspect of the invention includes a power supply unit including a power transmitting coil that supplies power to an endoscope in a contactless manner; a first optical communication unit that performs optical communication with the endoscope; an external trigger receiving unit that receives an external trigger showing a start instruction for power supply to the endoscope; and a power supply control unit that controls the power supply unit. The power supply control unit starts power supply from the power supply unit to the endoscope in the case where the external trigger receiving unit receives the external trigger. The first optical communication unit starts optical communication with a second optical communication unit provided in the endoscope and receives power reception information corresponding to an excess or deficiency in the amount of received power of the endoscope through optical communication from the second optical communication unit, in the case where the power supply is started. The power supply control unit controls the power supply unit on the basis of the power reception information received by the first optical communication unit, and adjusts the power to be transmitted from the power supply unit. 
     According to the aspect of the invention, if the external trigger is received and the power supply to the endoscope is started, optical communication with the endoscope is allowed. As a result, the power reception information corresponding to an excess or deficiency in the amount of received power of the endoscope is received through the optical communication from the endoscope. The power supply control unit controls the power supply unit on the basis of the received power reception information, and adjusts the power to be transmitted from the power supply unit. Accordingly, supply of the power required by the endoscope to the endoscope can be excellently performed through contactless power supply irrespective of the load fluctuation of the endoscope. 
     In the processor device for an endoscope according to another aspect of the invention, it is preferable that the external trigger receiving unit includes a mounting detection unit that detects whether or not the endoscope has been mounted on the processor device for an endoscope, and receives the time when the mounting of the endoscope has been detected as the external trigger in the case where the mounting detection unit detects the mounting of the endoscope. Accordingly, in the case where the endoscope is mounted on the processor device for an endoscope, contactless supply of power can be automatically performed. 
     In the processor device for an endoscope according to still another aspect of the invention, it is preferable that the external trigger receiving unit includes a test start switch that makes an instruction for the start of endoscopy, and receives a manual operation time of the test start switch as the external trigger if the test start switch is manually operated. Accordingly, if the test start switch is manually operated according to a user&#39;s intention, contactless supply of power can be performed. 
     In the processor device for an endoscope according to still another aspect of the invention, it is preferable that the power supply unit supplies power to the endoscope in a contactless manner using an electromagnetic resonance method, and the power supply control unit controls the frequency of an electric current made to flow to the power transmitting coil of the power supply unit, on the basis of the power reception information received by the first optical communication unit, and adjusts the power to be transmitted from the power supply unit. 
     In the processor device for an endoscope according to still another aspect of the invention, it is preferable that the power reception information is voltage information showing a direct current voltage corresponding to the load state of the endoscope, and the power supply control unit controls the frequency of the electric current made to flow to the power transmitting coil such that the electric current moves in a direction approaching a resonant frequency at which the power supply unit and the power receiving unit of the endoscope magnetically resonate with each other, in the case where the voltage information received by the first optical communication unit is lower than a first threshold value, and controls the frequency of the electric current made to flow to the power transmitting coil such that electric current moves in a direction away from the resonant frequency, in the case where the voltage information received by the first optical communication unit is higher than a second threshold value. 
     In the processor device for an endoscope according to still another aspect of the invention, it is preferable that the first threshold value is a value that is smaller than the second threshold value by a hysteresis width. Accordingly, the searching when the frequency of the electric current made to flow to the power transmitting coil is adjusted can be prevented. 
     In the processor device for an endoscope according to still another aspect of the invention, it is preferable to further include an image signal receiving unit that receives an image signal, which has been captured by the endoscope, in a contactless manner from an image signal transmitting unit provided in the endoscope; an image processing unit that performs image processing on the image signal received by the image signal receiving unit; and an output unit that outputs the image signal, which has been subjected to image processing by the image processing unit, to a display. Accordingly, the image signal can be received in a contactless manner from the endoscope, and the connector section of the endoscope can be made to have a waterproof structure. 
     In the processor device for an endoscope according to another aspect of the invention, it is preferable to further include a light source that supplies light for illumination to a light guide of the endoscope via a mounting unit on which the endoscope is mounted. 
     An endoscope system according to still another aspect of the invention includes the above processor device for an endoscope; and an endoscope connected to the processor device for an endoscope. The endoscope includes a power receiving unit including a power receiving coil that performs power reception in a contactless manner from the processor device for an endoscope; and a second optical communication unit that starts optical communication with the first optical communication unit provided in the processor device for an endoscope and transmits the power reception information corresponding to an excess or deficiency in the amount of received power of the endoscope through optical communication, in the case where power is supplied via the power receiving unit. 
     In the endoscope system according to still another aspect of the invention, it is preferable that the processor device for an endoscope includes a control unit that controls an imaging operation of the endoscope, and the control unit transmits a control signal for controlling the imaging operation of the endoscope from the first optical communication unit to the second optical communication unit. 
     In the endoscope system according to still another aspect of the invention, it is preferable that the endoscope includes an image signal transmitting unit that transmits an image signal, which has been captured by the endoscope, in a contactless manner to the image signal receiving unit provided in the processor device for an endoscope. 
     A contactless power supply method for an endoscope system according to still another aspect of the invention includes, in an endoscope system including a processor device for an endoscope having a power supply unit including a power transmitting coil, and a first optical communication unit, and an endoscope having a power receiving unit including a power receiving coil, and a second optical communication unit, a step of starting power supply from the power supply unit to the power receiving unit of the endoscope in the case where an external trigger receiving unit of the processor device for an endoscope receives an external trigger showing a start instruction for power supply to the endoscope; a step of causing, in the case where power supply is performed via the power receiving unit, the second optical communication unit to start optical communication with the first optical communication unit provided in the processor device for an endoscope and receive power reception information corresponding to an excess or deficiency in the amount of received power of the endoscope through optical communication; and a step of causing a power supply control unit provided in the processor device for an endoscope to control the power supply unit on the basis of the power reception information received via the first optical communication unit, and adjust the power to be transmitted from the power supply unit. 
     In the contactless power supply method for an endoscope system according to still another aspect of the invention, it is preferable that the professor device for an endoscope supplies power to the endoscope in a contactless manner using an electromagnetic resonance method, and in the case where the external trigger receiving unit receives the external trigger, the power supply control unit starts power supply from the power supply unit to the power receiving unit of the endoscope, acquires the power reception information from the second optical communication unit via the first optical communication, controls the frequency of an electric current made to flow to the power transmitting coil of the power supply unit on the basis of the acquired power reception information, and adjusts the power to be transmitted from the power supply unit. 
     According to the invention, the power reception information corresponding to an excess or deficiency in the amount of received power of the endoscope is received through optical communication with the endoscope, and the power to be transmitted in a contactless manner from the power supply unit to the endoscope using the received power reception information as feedback information is adjusted. Therefore, irrespective of the load fluctuation of the endoscope, supply of the power required by the endoscope to the endoscope can be excellently performed by contactless power supply. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an appearance view illustrating an endoscope system. 
         FIG. 2  is a block diagram illustrating the internal configuration of the endoscope system. 
         FIG. 3  is an appearance view of a connector section of an endoscope. 
         FIG. 4  is a view illustrating an embodiment of a mounting detection unit that detects mounting of the connector section of the endoscope. 
         FIG. 5  is a configuration view illustrating a power receiving unit of the endoscope and a power supply unit of a processor device for an endoscope, which are illustrated in  FIG. 1 . 
         FIG. 6  is a flowchart illustrating a contactless power supply method for the endoscope system. 
         FIG. 7A  and  FIG. 7B  are a graph illustrating the relationship between the frequencies of electric currents made to flow to a power transmitting coil and direct current voltages corresponding to the load states of the endoscope, with respect to time. 
         FIG. 8  is a side view of main parts of the processor device for an endoscope used in order to explain another embodiment of the mounting detection unit that detects the mounting of the connector section of the endoscope. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, embodiments of a processor device for an endoscope, an endoscope system, and a contactless power supply method for an endoscope system according to the invention will be described with reference to the accompanying drawings. 
     [Endoscope System] 
       FIG. 1  is an appearance view of the endoscope system according to the invention. 
     As illustrated in  FIG. 1 , the endoscope system  2  is constituted of an endoscope  10  and a processor device  11  for an endoscope. 
     The endoscope  10  is illustrated as a flexible mirror, and includes a flexible insertion section  13  inserted into a patient&#39;s body cavity, an operation section  15  disposed at a base end of the insertion section  13 , a universal cord  17  disposed at the operation section  15 , and a connector section  18  provided at an end of the universal cord  17  and connected to a connector section  12  that functions as a mounting unit of the processor device  11  for an endoscope. However, the endoscope  10  is not limited to the flexible mirror, and the invention can be applied to any other types of endoscopes, such as a hard mirror. 
     An observation window, an illumination window, and the like are provided at a tip surface of the insertion section  13 . An objective optical system that focuses photographic subject light from a part to be observed taken in by the observation window as an optical image, an imaging unit that converts the optical image focused by the objective optical system into electrical signals, and the like are arranged in a tip part  14  that constitutes the tip of the insertion section  13 . 
     Image signals output from the imaging unit are transmitted to an image signal transmitting unit  42  ( FIG. 2 ) by a transmission cable arranged to be inserted through the endoscope to the connector section  18  via the insides of the insertion section  13 , the operation section  15 , and the universal cord  17 . The image signals are converted into light signals by the image signal transmitting unit  42 , and are optically transmitted to the processor device  11  for an endoscope in a contactless manner. 
     Additionally, a light emitting part of a light guide  52  ( FIG. 2 ) that transmits light for irradiating a part to be observed from the illumination window is arranged at the tip part  14 . The light guide  52  is arranged to be inserted through the endoscope to the connector section  18  via the insides of the insertion section  13 , the operation section  15 , and the universal cord  17 . Additionally, a light guide rod  20  coupled to the light guide  52  protrudes from the connector section  18 . 
     A release button for recording an endoscope image as a still image, and the like, other than an angle knob for adjusting the orientation of the tip surface of the insertion section  13  in vertical and horizontal directions and a gas and water supply button for jetting air or water from the tip surface of the insertion section  13 , are provided in the operation section  15 . The orientation of the tip surface of the insertion section  13  is adjusted by bending a bending part provided in the vicinity of a base end side of the tip part  14 . 
     The universal cord  17  is covered with an outer wall part that is tubular, elongated, and flexible, and the transmission cable arranged to be inserted through cavity parts inside the insertion section  13  and the operation section  15 , the light guide  52 , a gas and water supply tube, and the like are arranged in a lumen inside the outer wall part so as to be inserted therethrough. 
       FIG. 2  is a block diagram illustrating the internal configuration of the endoscope system  2  of  FIG. 1 . 
     The connector section  18  of the endoscope  10  is connected to the connector section  12  of the processor device  11  for an endoscope. Power reception and power supply of power, transmission and reception of image signals, and transmission and reception of various kinds of control signal are performed in a contactless manner between the connector section  18  of the endoscope  10  and the connector section  12  of the processor device  11  for an endoscope. 
     Therefore, the connector section  18  of the endoscope  10  is provided with a power receiving unit  36  that receives power in a contactless manner, an image signal transmitting unit  42  that optically transmits image signals of an imaging unit  30  in a contactless manner, and a signal transmission/reception unit  50  that optically transmits and receives control signals that control the imaging unit  30 , and power reception information used for control of contactless power supply in a contactless manner and that functions as a second optical communication unit. 
     As described above, the connector section  18  of the endoscope  10  is connected to the connector section  12  of the processor device  11  for an endoscope. The processor device  11  for an endoscope performs supply (power supply) of power to the endoscope  10  connected (mounted) to the connector section  12 , and transmission and reception of various signals to and from the endoscope  10 . 
     The processor device  11  for an endoscope includes a light source  68 . Light for illumination from the light source  68  is supplied to the light guide  52  via the light guide rod  20 , and the light is transmitted from the light guide  52  to the tip part  14 . 
     The connector section  12  of the processor device  11  for an endoscope connected to the connector section  18  of the endoscope  10  is provided with a power supply unit  62  that supplies power to the power receiving unit  36  of the endoscope  10  in a contactless manner, an image signal receiving unit  64  that receives the image signals from the image signal transmitting unit  42  of the endoscope  10  in a contactless manner, and a signal transmission/reception unit  66  that transmits and receives signals in a contactless manner to and from the signal transmission/reception unit  50  of the endoscope  10  and that functions as a first optical communication unit. 
     Additionally, the processor device  11  for an endoscope takes in the image signals output from the imaging unit  30  of the tip part  14  of the endoscope  10 , performs various kinds of signal processing on the taken-in image signals, and generates image data that constructs a video (dynamic image) or a still image of a part to be observed. Then, the generated image data is output to a display (monitor)  19  connected by a cable, and the image or the like of the part to be observed is displayed on the monitor  19 . Additionally, the generated image data is recorded on a recording medium if necessary. 
     The endoscope  10  is detachably mounted (connected) to the connector section  12  of the processor device  11  for an endoscope by the connector section  18 . In the endoscope system  2  of the present embodiment, by virtue of the mounting between the connector section  18  of the endoscope  10  and the connector section  12  of the processor device  11  for an endoscope, an internal circuit of the endoscope  10  and an internal circuit of the processor device  11  for an endoscope are connected together by a contactless device, such as a transformer or a photo-coupler, via these connector sections. Accordingly, the electrical insulation between the internal circuit of the endoscope  10  and the internal circuit of the processor device  11  for an endoscope is ensured. That is, the invention is configured so that optical communication of control signals, contactless power supply of power, and optical communication of image signals can be realized. 
     Power required for driving of the internal circuit of the endoscope  10  is supplied from the processor device  11  for an endoscope by contactless power supply means consisting of the power supply unit  62  in the processor device  11  for an endoscope and the power receiving unit  36  in the endoscope  10 . The power receiving unit  36  is arranged at the connector section  18  of the endoscope  10 , and the power supply unit  62  is arranged at the connector section  12  of the processor device  11  for an endoscope. 
     The contactless power supply means is means for transmitting and receiving power in a contactless manner using electromagnetic coupling. If the connector section  18  of the endoscope  10  is mounted on the connector section  12  of the processor device  11  for an endoscope, the power supply unit  62  and the power receiving unit  36  are arranged close to each other at a distance allowing electromagnetic coupling, and are brought into a state where contactless power supply from the power supply unit  62  to the power receiving unit  36  is allowed. A commercial power source  100  is connected to the power supply unit  62  via the stabilized power control unit  63  outside the processor device  11  for an endoscope. The power supplied from the commercial power source  100  and stabilized by the stabilized power control unit  63  is supplied to the power supply unit  62 . By the power supplied from the stabilized power control unit  63  to the power supply unit  62 , the power is supplied from the power supply unit  62  to the power receiving unit  36  in a contactless manner. The power receiving unit  36  receives the power in a contactless manner from the power supply unit  62 . In addition, the details of this contactless supply of power will be described below. 
     The endoscope  10  includes a power generating unit  32  connected to the power receiving unit  36 , and the power generating unit  32  generates various kinds of driving power required by an internal circuit including the imaging unit  30  and the like, and supplies the generated power. For example, the power generating unit  32  has an electric current induced in the power receiving unit  36  inputs thereto, and generates the driving power to be supplied to an internal circuit including the imaging unit  30 , a central processing unit (CPU)  46 , and the like from the input electric current. 
     The imaging unit  30  is arranged at the tip part  14  of the endoscope  10 . The imaging unit  30  is a device that converts the light of the optical image of the part to be observed, which has been taken in by the observation window and focused by the objective optical system, into electrical signals, and outputs the converted electrical signals as image signals, as described above. As the imaging unit  30 , for example, a solid-state imaging element, such as a charge coupled device (CCD) image sensor or a complementary metal oxide semiconductor (CMOS) image sensor, can be included. 
     In the present embodiment, transmission and reception of image signals between the endoscope  10  and the processor device  11  for an endoscope are performed by contactless optical communication means. The image signals output from the imaging unit  30  are transmitted by contactless optical transmission via the connector section  12  of the processor device  11  for an endoscope from the connector section  18  of the endoscope  10 . In the present embodiment, an analog/digital converter (A/D converter)  34 , a digital signal processor (DSP)  38 , and a timing signal generator (TSG)  44 , and the like are provided in order to process the image signals from the imaging unit  30 . The image signals from the imaging unit  30  are changed from analog signals to digital signals by the A/D converter  34 . Image signals output from the A/D converter  34  are transmitted to the DSP  38 . The DSP  38  performs required processing, such as amplification, gamma correction, white balance processing, and the like on the image signals from the A/D converter  34 . 
     For example, the following configuration is provided in order to perform contactless optical transmission between the endoscope  10  and the processor device  11  for an endoscope. The endoscope  10  includes an endoscope-side digital interface (DI)  40  connected to the DSP  38 , and the image signal transmitting unit  42  connected to endoscope-side DI  40 . The image signals processed by the DSP  38  is transmitted to the image signal transmitting unit  42  via the endoscope-side DI  40 . Processing is performed on the image signals from the imaging unit  30 , and light signals are transmitted from the image signal transmitting unit  42  to the processor device  11  for an endoscope according to the processed image signals. The image signal transmitting unit  42  may be a light emitting device that can radiate light for optical communication, and can include a laser light emitting element, a light emitting diode, or the like. The laser light emitting element means an element that radiates laser light that is coherent light, and includes a gas laser, a solid-state laser, a semiconductor laser, or the like. 
     The processor device  11  for an endoscope includes the image signal receiving unit  64  that receives the light signals from the image signal transmitting unit  42 , a processor-side DI  70  connected to the image signal receiving unit  64 , and a signal processing circuit  72  that functions as an image processing unit and an output unit that are connected to the processor-side DI  70 . The image signal receiving unit  64  is a light receiving device that converts the received light signals into electrical signals, and can include, for example, a light-receiving element, such as a photodiode or a semiconductor device such as a phototransistor. The image signals, which have been optically received by the image signal receiving unit  64  and converted into electrical signals, are converted into image signals for display by the signal processing circuit  72  via the processor-side DI  70 , and are output to the monitor  19 . In addition, signal processing, such as gamma correction and white balance processing, may be performed by the signal processing circuit  72  of the processor device  11  for an endoscope, without being limited to a case where the signal processing is performed by the DSP  38  of the endoscope  10 . 
     In the present embodiment, image signal transmission/reception means based on contactless optical communication is constituted of the image signal transmitting unit  42  and the image signal receiving unit  64 . In the image signal transmitting unit  42  that transmits the image signals of the imaging unit  30  in a contactless manner, and the image signal receiving unit  64  that receives signals from the image signal transmitting unit  42  in a contactless manner, a wireless communication method can be used, without being limited to the contactless optical communication (optical wireless communication method). The optical wireless communication method means a method that transmits and receives signals using infrared rays or the like and the wireless communication method means a method that transmits and receives signals using wireless communication (electromagnetic waves). 
     If the connector section  18  of the endoscope  10  is mounted on the connector section  12  of the processor device  11  for an endoscope, the image signal transmitting unit  42  and the image signal receiving unit  64  are arranged close to each other at a distance allowing optical communication, and are set to a state where contactless optical communication from the image signal transmitting unit  42  to the image signal receiving unit  64  is allowed. 
     Transmission and reception of control signals between the endoscope  10  and the processor device  11  for an endoscope are performed through contactless optical communication. The TSG  44  and the CPU  46  are connected to the imaging unit  30 . The TSG  44  and the CPU  46  output a driving signal for allowing the imaging unit  30  to acquire the image signals to the imaging unit  30 . An endoscope-side communication interface (CI)  48  and the signal transmission/reception unit  50  are connected to the CPU  46 . The signal transmission/reception unit  50  is a device that performs contactless optical transmission and reception of the control signals between the endoscope  10  and the processor device  11  for an endoscope, and includes a light emitting device that optically transmits the control signals to the processor device  11  for an endoscope as light signals, and a light receiving device that receives the control signals from the processor device  11  for an endoscope as light signals. The signal transmission/reception unit  50  can include, for example, contactless optical data communication based on Infrared Data Association (IrDA) provided with an infrared light emitting element that optically transmits signals (infrared rays), and a light receiving element (a photodiode, a phototransistor, or the like) that optically receives signals. At least the signal transmission/reception unit  50  is arranged at the connector section  18  of the endoscope  10 . Other devices, for example, the endoscope-side CI  48  and the like, may be arranged at the connector section  18  of the endoscope  10 . 
     The processor device  11  for an endoscope includes the signal transmission/reception unit  66  that optically transmits and receives the control signals between the signal transmission/reception unit  50  of the endoscope  10  and a processor-side CI  74  connected to the signal transmission/reception unit  66 . The signal transmission/reception unit  66  is a device that can optically transmit and receive the control signals between the endoscope  10  and the processor device  11  for an endoscope, and includes a light emitting device that optically transmits the control signals to the endoscope  10  as light signals, and a light receiving device that receives the control signals from the endoscope  10  as light signals. The signal transmission/reception unit  66  of the processor device  11  for an endoscope can include, for example, contactless optical data communication based on IrDA provided with an infrared light emitting element that optically transmits signals different from those of the signal transmission/reception unit  50  of the endoscope  10  (infrared rays), and a light receiving element (a photodiode, a phototransistor, or the like) that optically receives signals different from those of the signal transmission/reception unit  50 . Generally, infrared rays mean electromagnetic waves that have a wavelength of 0.7 μm to 1 mm. 
     If the connector section  18  of the endoscope  10  is mounted on the connector section  12  of the processor device  11  for an endoscope, the signal transmission/reception units  50  and  66  are arranged close to each other at a distance allowing optical communication, and are set to a state where contactless optical transmission and reception are allowed between the signal transmission/reception units  50  and  66 . 
     The processor device  11  for an endoscope includes the light source  68 . The light source  68  can include, for example, a xenon lamp, or a semiconductor device, such as a laser diode or a light emitting diode. The endoscope  10  includes the light guide  52 . The light guide rod  20  connected to the light guide  52  is provided at an end of the light guide  52 . The light guide rod  20  protrudes from the connector section  18 , and is connected to the connector section  12  of the processor device  11  for an endoscope. If the connector section  18  of the endoscope  10  is mounted on the connector section  12  of the processor device  11  for an endoscope, the light guide rod  20  and the light source  68  are aligned with each other, and the light from the light source  68  is transmitted to the tip part  14  via the light guide rod  20  and the light guide  52 . 
     Additionally, the processor device  11  for an endoscope includes a control unit  76 , and an input unit  80  including an operation switch, a test start switch, a keyboard, a mouse, and the like, and the control unit  76  controls the entire endoscope system  2  generally according to operator&#39;s the operations input from the input unit  80 . In addition, the test start switch included in the input unit  80  and the control unit  76  function as an external trigger receiving unit. 
     For example, the control unit  76  controls the power supply unit  62 , the light source  68 , the processor-side DI  70 , and the like, sends control signals for controlling imaging operation and the like to the CPU  46  and the like that constitute the internal circuit of the endoscope  10 , and controls the entire endoscope system  2 . 
     Moreover, the control unit  76  transmits control signals or the like based on a user&#39;s instruction input in which the user indicates power ON or OFF of the processor device  11  for an endoscope by the input unit  80 , to the CPU  46  of the endoscope  10  through the signal transmission/reception units  66  and  50 . 
     Additionally, the control signals from the CPU  46  of the endoscope  10  are transmitted to the control unit  76  of the processor device  11  for an endoscope through signal transmission/reception units  66  and  50  and the processor-side CI  74 , and the control unit  76  controls the processor device  11  for an endoscope according to the control signals. 
       FIG. 3  is an appearance view illustrating the connector section  18  of the endoscope  10 . As described above, the endoscope  10  and the processor device  11  for an endoscope perform power reception and power supply of power, transmission and reception of image signals, and transmission and reception of control signals in both directions, in a contactless manner. It is not necessary to provide the connector section  18  with an electrical contact directly connected to the processor device  11  for an endoscope. 
     Therefore, it is possible to provide a waterproof structure in which the connector section  18  of the endoscope  10  is covered with resin that has electrical insulation and has excellent chemical resistance. By making the connector section  18  into a waterproof structure, electrical components or the like inside the connector section  18  can be protected from cleaning water or the like, it is not necessary to attach a separate waterproofing cap in the case of cleaning or disinfection, and it is suitable particularly when the endoscope  10  is cleaned and sterilized by a high-pressure steam sterilizer (autoclave device). 
     As illustrated in  FIG. 3 , the connector section  18  of the endoscope  10  includes the light guide rod  20  that protrudes from the connector section  18 , and a shaft  22 . 
     The connector section  18  has a tubular shape, and the above-described power receiving unit  36 , image signal transmitting unit  42 , and signal transmission/reception unit  50  are arranged in a space inside the connector section. 
     The shaft  22  is used for the alignment between the image signal transmitting unit  42  of the endoscope  10  and the image signal receiving unit  64  of the processor device  11  for an endoscope. Particularly, the image signal transmitting unit  42  is arranged in an extending direction of a central axis of the shaft  22 . A window  22 A is provided at the tip of the shaft  22  in order to allow light to be transmitted therethrough. Image signals are optically transmitted and received in a contactless manner between the image signal transmitting unit  42  and the image signal receiving unit  64  via the window  22 A. 
     Additionally, a window  23  is provided at a position corresponding to the signal transmission/reception unit  50  in a connecting surface of the connector section  18 . Control signals are optically transmitted and received in a contactless manner between the signal transmission/reception units  50  and  66  via the window  23 . 
     The power receiving unit  36  is arranged at a position near the connecting surface of the connector section  18 . The power receiving unit  36  is arranged inside the connector section  18 , and is not exposed to the outside. 
     Additionally, a gas and water supply connector  24 , a balloon connector  25 , a ventilation connector  26 , a connector  27  used when an electrosurgical unit (electric scalpel) or the like is used, a suction connector  28 , and a sub-water supply connector  29  are arranged on a side surface of the connector section  18 . 
       FIG. 4  is a view illustrating an embodiment of a mounting detection unit that detects mounting of the connector section  18  of the endoscope  10 , and is a side view of main parts of the connector section of the processor device  11  for an endoscope. 
     As illustrated in  FIG. 4 , a light guide (LG) detection switch  90  is disposed in the vicinity of the connector section of the processor device  11  for an endoscope on which the connector section  18  of the endoscope  10  is mounted. 
     The LG detection switch  90  detects electrical connection with the light guide rod  20  covered with metal, thereby detecting that the light guide rod  20  has been inserted (that is, that the connector section  18  of the endoscope  10  has been mounted on the processor device  11  for an endoscope). If insertion of the light guide rod  20  is detected, the LG detection switch  90  outputs the detection signal to a power supply control unit  62 C or a control unit  76  (to be described below) as an external trigger. 
     In addition, as the LG detection switch  90 , a microswitch that detects mechanical contact with the light guide rod  20  without being limited to the electrical connection with the light guide rod  20 , a photointerrupter that detects the presence/absence of the light guide rod  20  optically, or the like may be used. 
       FIG. 5  is a configuration view illustrating the power receiving unit  36  of the endoscope  10  and the power supply unit  62  of the processor device  11  for an endoscope that are illustrated in  FIG. 1 . 
     The power supply unit  62  is constituted of a power transmitting coil  62 A, a power transmitting integrated circuit (IC)  62 B, and a power supply control unit  62 C. 
     The stabilized power from the stabilized power control unit  63  is supplied to the power transmitting IC  62 B, and the power transmitting IC  62 B supplies a variable frequency current (high-frequency current) to the power transmitting coil  62 A by using the power input from the stabilized power control unit  63  as power. 
     The power supply control unit  62 C controls the power transmitting IC  62 B that constitutes the power supply unit  62  and that adjusts the power transmitted from the power supply unit  62 . If a detection signal (external trigger) showing mounting of the endoscope  10  is applied from the LG detection switch  90 , the test start switch that makes an instruction for the start of endoscopy of the input unit  80  is manually operated, and if an instruction input (external trigger) is applied via the control unit  76 , the power supply unit  62  is actuated to start power supply to the endoscope  10 . 
     Additionally, the power supply control unit  62 C controls the power transmitting IC  62 B on the basis of power reception information that is applied via the control unit  76  and corresponds to an excess or deficiency in the amount of received power of the endoscope  10 , and adjusts the power transmitted from the power supply unit  62 . In the present embodiment, a voltage value (voltage information) V rect  showing a direct current voltage rectified after power has been received by the power receiving unit  36  of the endoscope  10  and a direct current voltage fluctuating in response to the load state of the endoscope  10  are used as the above power reception information, and the power supply control unit  62 C controls the frequency of an electric current made to flow from the power transmitting IC  62 B to the power transmitting coil  62 A such that the voltage value V rect  falls within a desired voltage range. 
     The power receiving unit  36  of the endoscope  10  is constituted of a power receiving coil  36 A and a power receiving IC  36 B. The power receiving coil  36 A supplies power to the endoscope  10  in a contactless manner using an electromagnetic resonance method, and is magnetically coupled with a power transmitting coil  62 A, and an induced current resulting from an alternating field (magnetic flux) caused by a high-frequency current that flows into the power transmitting coil  62 A is generated in the power receiving coil  36 A. 
     The power receiving IC  36 B includes a rectifier circuit, and rectifies the induced current caused in the power receiving coil  36 A using the rectifier circuit and then outputs the rectified current to the power generating unit  32 . 
     The power generating unit  32  illustrated in  FIG. 2  generates various kinds of driving power required by the internal circuit of the endoscope  10 , using the power received by the power receiving unit  36  as mentioned above as power, and supplies the generated power. 
     The CPU  46  acquires the voltage value V rect  for a reference power in the power generating unit  32  as voltage information from the power generating unit  32 , and notifies the processor device  11  for an endoscope of the acquired voltage information as feedback information via the endoscope-side CI  48  and the signal transmission/reception unit  50  that performs contactless optical communication. 
     In addition, the voltage value V rect  fluctuates in response to the load state of the endoscope  10 , and fluctuates depending on the power transmitted from the power supply unit  62 . 
     [Contactless Power Supply Method for Endoscope System] 
     Next, the contactless power supply method for the endoscope system  2  having the above configuration will be described. 
       FIG. 6  is a flowchart illustrating the contactless power supply method for the endoscope system, and illustrating mainly the operation of the processor device  11  for an endoscope. 
     In  FIG. 6 , if the power supply control unit  62 C determines whether or not an external trigger showing a start instruction for power supply to the endoscope  10  has been input (Step S 10 ), and the external trigger has been input (when the determination result is “Yes”), the power supply to the endoscope  10  is started (Step S 12 ). 
     Here, the external trigger is applied from the LG detection switch  90  to the power supply control unit  62 C when the LG detection switch  90  has detected insertion of the light guide rod  20  (namely, when mounting of the endoscope  10  has been detected). 
     Additionally, the power supply when the power supply to the endoscope  10  is started, as illustrated in  FIG. 7A , is performed by raising (sweeping) the frequency of an electric current made to flow to the power transmitting coil  62 A of the power supply unit  62  slowly from a frequency sufficiently lower than a resonant frequency at which the power supply unit  62  and the power receiving unit  36  magnetically resonate with each other from the time when the external trigger has been input. Accordingly, the power supplied from the power supply unit  62  to the power receiving unit  36  becomes slowly larger. As a result, as illustrated in  FIG. 7B , the voltage value V rect  showing the direct current voltage caused in the endoscope  10  also becomes larger in accordance with the supplied power. 
     If the power supply to the endoscope  10  is started, the endoscope  10  is automatically powered on, or is powered on by a control signal applied through optical communication from the processor device  11  for an endoscope, and supply of power to the internal circuit of the processor device  11  for an endoscope is started. 
     If the endoscope  10  is powered on, the CPU  46 , the signal transmission/reception unit  50 , and the like become operable. As a result, the endoscope  10  and the processor device  11  for an endoscope start bidirectional optical communication via the signal transmission/reception units  50  and  66  (Step S 14 ). Then, voltage information showing a current voltage value V rect  from the endoscope  10  is transmitted to the processor device  11  for an endoscope through optical communication as feedback information, and the control unit  76  of the processor device  11  for an endoscope receives voltage information showing the current voltage value V rect  (acquisition), and outputs the acquired voltage information to the power supply control unit  62 C (Step S 14 ). 
     The power supply control unit  62 C determines whether or not the current voltage value V rect  is smaller than a first threshold value TH 1  (5.2 V in the present embodiment) using the voltage information acquired via the control unit  76  (Step S 16 ). In Step S 16 , if it is determined that the voltage value V rect  is smaller than 5.2 V (in the case of “Yes”), the power supply control unit  62 C controls the frequency of the electric current made to flow to the power transmitting coil  62 A of the power supply unit  62 , and raises the frequency in a direction approaching the resonant frequency (Step S 18 ). Accordingly, the power supplied to the endoscope  10  can be increased, and the voltage value V rect  of the power of the endoscope  10  can be raised. 
     Meanwhile, if the power supply control unit  62 C determines that the current voltage value V rect  is equal to or more than 5.2 V (in the case of “No”), it is further determined whether or not the current voltage value V rect  is larger than a second threshold value TH 2  (5.3 V in the present embodiment) (Step S 20 ). In Step S 20 , if it is determined that the voltage value V rect  is larger than 5.3 V (in the case of “Yes”), the power supply control unit  62 C controls the frequency of the electric current made to flow to the power transmitting coil  62 A of the power supply unit  62 , and lowers the frequency in a direction away the resonant frequency (Step S 22 ). Accordingly, the power supplied to the endoscope  10  can be decreased, and the voltage value V rect  of the power of the endoscope  10  can be lowered. 
     In Step S 20 , if it is determined that the voltage value V rect  is equal to or smaller than 5.3 V (in the case of “No”), the power supply control unit  62 C maintains the frequency of the electric current made to flow to the power transmitting coil  62 A of the power supply unit  62  (Step S 24 ). Accordingly, the power supplied to the endoscope  10  is also maintained. 
     The processing of the above Step S 14  to Step S 24  is continuously performed at given time intervals. 
     Next, the control of power (the frequency of the electric current made to flow to the power transmitting coil  62 A of the power supply unit  62 ) supplied in a contactless manner from the power supply unit  62  will be described referring to  FIGS. 7A and 7B . 
     If an external trigger is input as illustrated in  FIGS. 7A and 7B , the power supply control unit  62 C slowly raises the frequency of the electric current made to flow to the power transmitting coil  62 A from a frequency sufficiently lower than the resonant frequency. The voltage value V rect  rises with the rise of this frequency. At a time t 1 , if the voltage value V rect  reaches the first threshold value TH 1 , the frequency at the time t 1  is maintained. 
     Thereafter, at a time t 2 , if the voltage value V rect  exceeds the second threshold value TH 2 , the frequency is lowered slowly from the maintained frequency, and at a time t 3 , if the voltage value V rect  reaches the second threshold value TH 2 , the frequency at the time t 3  is maintained. 
     Subsequently, the load of the endoscope  10  becomes larger due to the start of imaging by the endoscope  10 , or the like. As a result, at a time t 4 , if the voltage value V rect  becomes smaller than the first threshold value TH 1  due to a voltage drop resulting from the load, the frequency is slowly raised from the maintained frequency. 
     In this way, by adjusting the frequency (supplied power) of the electric current made to flow to the power transmitting coil  62 A of the power supply unit  62  corresponding to a change (particularly a change exceeding the range between the first threshold value TH 1  and the second threshold value TH 2 ) in the voltage value V rect  of the endoscope  10 , an excess or deficiency in power can be prevented from occurring with respect to the load fluctuation of the endoscope  10 . 
     In addition, the hysteresis width (0.1 V in the present embodiment) is set between the first threshold value TH 1  and the second threshold value TH 2 , and this prevents searching when the frequency of the electric current made to flow to the power transmitting coil  62 A is adjusted. Here, the hysteresis width is a dead band, and when the voltage value V rect  of the endoscope  10  falls within a range of the hysteresis width, switching of adjustment of the frequency of the electric current made to flow to the power transmitting coil  62 A is not performed. 
       FIG. 8  is a view illustrating another embodiment of the mounting detection unit that detects the mounting of the connector section  18  of the endoscope  10 , and a side view of main parts of the processor device  11  for an endoscope. 
     As illustrated in  FIG. 8 , a return light detecting unit  92  is disposed in the vicinity of the light source  68  of the processor device  11  for an endoscope on which the connector section  18  of the endoscope  10  is mounted. 
     The return light detecting unit  92  detects illumination light, which enters an end surface of the light guide rod  20  from the light source  68 , as the return light from the tip of the light guide  52  or the reflected light from the end surface of the light guide rod  20 . The return light detecting unit  92  detects the return light of the illumination light, which has entered the end surface of the light guide rod  20 , thereby detecting that the light guide rod  20  has been inserted (that is, that the connector section  18  of the endoscope  10  has been mounted on the processor device  11  for an endoscope). In addition, when the light guide rod  20  is not inserted, the return light detecting unit  92  cannot receive return light, and accordingly can detect the presence/absence of insertion of the light guide rod  20 . 
     If insertion of the light guide rod  20  is detected, the return light detecting unit  92  outputs the detection signal to the aforementioned power supply control unit  62 C or control unit  76  as an external trigger. 
     [Others] 
     In the present embodiment, a case where contactless power supply is started by using the detection time of mounting of the endoscope detected by the mounting detection unit represented by the LG detection switch  90 , the return light detecting unit  92 , and the like as an external trigger, and a case where contactless power supply is started by using the manual operation time of the test start switch that makes an instruction for the start of the endoscopy of the input unit  80  as an external trigger have been described. However, the external trigger from the mounting detection unit and the external trigger from the test start switch may be separately used as follows. 
     When the processor device  11  for an endoscope is powered on in a state where the endoscope  10  is mounted on the processor device  11  for an endoscope, only the external trigger from the test start switch is validated. This is because contactless power supply is automatically started in a state where the mounting of the endoscope  10  is incomplete. On the other hand, when the endoscope  10  is mounted on the processor device  11  for an endoscope in a state where the processor device  11  for an endoscope is powered on, only the external trigger from the mounting detection unit is validated. This is because, wasted contactless power supply resulting from the operation of the test start switch in a state where the endoscope  10  is not mounted can be prevented, and contactless power supply can be started in conjunction with the mounting of the endoscope  10 . 
     Additionally, as well as a case where supplied power is controlled by controlling the frequency of the electric current made to flow to the power transmitting coil of the power supply unit, the supplied power may be controlled by adjusting the duty ratio of switching on and off of an inverter connected to the power transmitting coil. 
     Moreover, in the present embodiment, the voltage information showing the direct current voltage (voltage value V rect ) in response to the load state of the endoscope is received from the endoscope as the feedback information when controlling supplied power. However, the invention is not limited to this. For example, the endoscope may determine an excess or deficiency in power, and may transmit the determination result to the processor device for an endoscope through optical communication from the endoscope. 
     Additionally, it is obvious that the invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention.