An endoscope of the invention includes: an LED for supplying illumination light to illuminate a subject; an image pickup device for picking up an image of a region to be inspected of the subject; a video display device provided with a monitor portion on which an endoscope image of the region to be inspected picked up by the image pickup device is displayed and an exterior member for holding the monitor portion; a power supply control circuit for supplying electric power to drive the LED and cause the LED to emit illumination light; and a heat radiation portion for radiating heat generated by the power supply control circuit formed on a rear surface opposing to a disposition surface of the exterior member on which the monitor portion of the video display device is provided.

CROSS REFERENCE TO RELATED ART

This application claims the benefit of Japanese Application No. 2006-184784 filed in Japan on Jul. 4, 2006, the contents of which are incorporated herein by this reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an endoscope including an operation portion to which a display device for displaying an endoscope image picked up by image pickup portion is connected.

2. Description of Related Art

Conventionally, as a light source of an endoscope, well-known is a light source lamp built in a light source device as a peripheral device to which an endoscope is connected. When illumination light is supplied to an endoscope from a light source device, the illumination light emitted from a light source lamp is transmitted to a distal end of an insertion portion via from a universal cord to an operation portion of the endoscope, by means of light guide fiber extended inside of the endoscope, and then the illumination light is irradiated from the distal end of the insertion portion to a region to be inspected.

In addition, in recent years, for the purpose of simplifying a whole endoscope apparatus including an endoscope and peripheral devices, well-known is an endoscope having a configuration in which a light source is configured of a light emitting diode provided in the endoscope and a display device for displaying an endoscope image is connected to an operation portion.

Providing a light source configured of the light emitting diode in the endoscope eliminates the need for a light source device connected to the endoscope, thereby simplifying the endoscope apparatus. In addition, the light emitting diode is capable of emitting light with lower electric power compared with light source lamp and the like, thereby realizing power saving in the endoscope apparatus. Furthermore, connecting the display device to the operation portion eliminates the need for a monitor device to be separately connected to the endoscope, thereby simplifying the endoscope apparatus.

In addition, in the endoscope, also provided is a light emitting diode driving circuit which is a light source driving circuit for applying electric power supplied from a battery provided to the display device, for example, to the light emitting diode after adjusting the electric power to the current rating of the light emitting diode.

Incidentally, an endoscope generally has watertight structure, since the outer surface of the endoscope is cleaned after use. That is, inside of the endoscope except for an opening of a duct and the like, is occluded by an exterior member. In order to reduce the weight of the whole endoscope, the exterior member of the endoscope is usually made of plastic material.

However, if the light emitting diode emits light, and in addition, the light emitting diode driving circuit continues to be driven, for example, in an enclosed space inside the operation portion in the endoscope covered with the plastic exterior member, there is a problem such that the light emitting diode is degraded by heat radiated in the enclosed space inside the operation portion due to the light emission of the light emitting diode and the driving of the light emitting diode driving circuit, and the lifetime of the light emitting diode is shortened, since the plastic exterior member has a low heat transfer efficiency.

Therefore, conventionally, there has been a compelling circumstance to make the light emitting diode emit light with electric power lower than the rated value in consideration of heat radiation efficiency of the plastic exterior member and the lifetime of the light emitting diode.

In view of such a circumstance, Japanese Unexamined Patent Application Publication No. 9-285443 discloses an endoscope having a configuration in which a small size illumination lamp as a light source is provided in a distal end portion of an insertion portion of the endoscope, and a light emission control circuit serving as a light source driving circuit for supplying electric power to the small size illumination lamp is provided in an operation portion of the endoscope. With such a configuration, the small size illumination lamp and the light emission control circuit are provided in different spaces, so that a heat radiating position from the small size illumination lamp and a heat radiating position from the light emission control circuit are different. Therefore, in the configuration, heat radiation points are dispersed, so that heat is radiated from the whole endoscope, while preventing localized heat radiation.

In addition, Japanese Unexamined Patent Application Publication No. 2002-112953 discloses a light source device which is mounted to a light source mounting port of an operation portion of an endoscope, and the light source has such a configuration that an LED lamp as a light source and a constant current source as a light source driving circuit are disposed separately from each other. With such a configuration, a heat radiating position from the LED lamp and a heat radiating position from the constant current source are different, thereby preventing localized heat radiation.

SUMMARY OF THE INVENTION

Briefly, an endoscope of the present invention comprises: an elongated insertion portion inserted into a subject; an operation portion provided in a linked manner on a proximal end side of the insertion portion; illumination portion for supplying illumination light for illuminating the subject, the illumination portion being provided in the insertion portion or in the operation portion; image pickup portion for picking up an image of a region to be inspected of the subject, the image pickup portion being provided in the insertion portion or in the operation portion; a display device including a display portion on which an endoscope image of the region to be inspected picked up by the image pickup portion is displayed and a frame body for holding the display portion, the display device being connected to the operation portion; a light source driving circuit for supplying electric power to drive the illumination portion and cause the illumination portion to emit illumination light, the light source driving circuit being provided in one of the insertion portion, the operation portion, and the display device; and a heat radiation portion for radiating heat generated from the light source driving circuit, the heat radiation portion being formed on a rear surface opposing to a disposition surface of the frame body on which the display portion in the display device is disposed.

The above and other objects, features and advantages of the invention will become more clearly understood from the following description referring to the accompanying drawings.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that, an endoscope will be described taking a medical endoscope as an example in the embodiment below.

FIG. 1is a perspective view showing an endoscope according to an embodiment of the present invention,FIG. 2is a partial perspective view showing the endoscope inFIG. 1viewed from a rear surface side inFIG. 1,FIG. 3is a partially enlarged plan view showing a state where a video display device of the endoscope inFIG. 1is rotatable, andFIG. 4is a plan view of the video display device of the endoscope inFIG. 1.

As shown inFIG. 1, an endoscope main body1bof an endoscope1has a main part configured of an insertion portion2inserted into a region to be inspected in a body cavity as a subject, an operation portion3provided in a linked manner on a proximal end side of the insertion portion2, and a video display device4which is a display device connected to an upper end of the operation portion3.

The insertion portion2is formed to be flexible in an elongated shape, and has a main part configured of a rigid distal end portion5located on a distal end side thereof, a bending portion6provided in a linked manner on a proximal end side of the distal end portion5, and a flexible portion7provided in a linked manner on a proximal end side of the bending portion6.

The operation portion3has a main part configured of a grasping portion8to be grasped by an operator when the operator grasps the endoscope1, and an operation portion main body9provided on a proximal end side of the grasping portion8.

The grasping portion8has an exterior formed in a shape such that an operator can grip with the thumb T (seeFIG. 3) and the other fingers of his or her left hand, for example in a bar-like shape. Note that the grasping portion8may be formed in a shape such that the operator can grip with his or her right hand.

In addition, the grasping portion8includes, on a rear surface1hside of the endoscope1, a treatment instrument insertion port10for inserting and withdrawing a treatment instrument into and from a body cavity by inserting and withdrawing the treatment instrument such as a forceps through the suction duct100to be described later (seeFIGS. 5 and 6) which is extended inside the endoscope1.

As shown inFIG. 2, the operation portion main body9has, on the rear surface1hside of the endoscope1, a suction base11used for sucking liquid such as body fluid and phlegm from the body cavity.

To the suction base11, a suction device is connectable via a tube not shown. An operator activates the suction device and operates a suction button11a(seeFIG. 2) to be described later, and thereby the operator can cause the suction device to suck body fluid, phlegm and the like from the body cavity via the suction duct100which is a fluid duct extended in the operation portion3and the insertion portion2such that one end100tis opened at the operation portion main body9and the other end100sis opened on a distal end surface5sof the distal end portion5, as shown inFIG. 6to be described later.

Note that a tube may be inserted into a flow path in the suction duct100, and via the tube, an insufflation device for insufflating air into the body cavity may be connectable to the suction base11communicating with inside of the tube.

In addition, the operation portion main body9has on the left side inFIG. 1a vent base12for insufflating air into the insertion portion2and the operation portion3in performing a leakage inspection of the endoscope1.

To the vent base12, an air-feeding device is connectable via a tube not shown. The operator activates the air-feeding device and feeds air in water into the endoscope1from the vent base12, thereby allowing a leakage inspection of the endoscope1.

Furthermore, to the vent base12, a cap and the like, not shown, for releasing air from inside of the endoscope1is detachably provided such that a part of the endoscope1, for example, a rubber, not shown, covering an outer circumference of the distal end portion5does not burst due to negative pressure when the endoscope1is left under negative pressure environment, for example, a sterilization processing or a transportation by air.

In addition, the operation portion main body9has, on a front surface1zside of the endoscope1, a bending operation lever13for bending a bending portion6in for example up and down directions, through a bending operation wire60(seeFIG. 5).

The bending operation wire60is extended in the insertion portion2and the operation portion3, with one end fixed to a distal end of a bending piece not shown in the bending portion6or to the distal end portion5, and the other end fixed to a pulley and the like, not shown, provided in the operation portion3.

The bending operation lever13is provided at a position adjacent to the grasping portion8such that the operator can operate the lever with the thumb T of the left hand gripping the grasping portion8. In addition, the bending operation lever13has an L shape formed by a finger-hooking portion13aprovided to the operation portion main body9on the front surface1zside of the endoscope1and an arm portion13bprovided in a linked manner to the finger-hooking portion13a.

In the bending operation lever13, the finger-hooking portion13ais provided at a predetermined position of the operation portion main body9with the arm portion13brotatably pivoted to the rotational shaft14passing through the operation portion main body9in the right and left direction inFIG. 1.

Furthermore, as shown inFIG. 2, the operation portion main body9has, on the rear surface1hside of the endoscope1, an image switch15configured of an image recording switch15aand an image reproduction switch15b. The image recording switch15ais turned on when recording a video displayed on the video display device4into a recording medium of a recording control circuit31to be described later (seeFIG. 6), and the image reproduction switch15bis turned on when reproducing the recorded image.

In addition, the above-described suction button11ais provided to the operation portion main body9so as to be positioned on the rear surface1hside of the endoscope1and in the vicinity of the image switch15.

In the grasping portion8, for example, a white light emitting diode (hereinafter referred to as LED)16, which is illuminating means configuring an illumination portion for supplying illumination light to illuminate a subject, is provided by means to be described later. In addition, in the operation portion main body9, there is disposed an image pickup device17configured of CCD, CMOS, or the like serving as image pickup means configuring an image pickup portion for picking up an image of the region to be inspected.

The video display device4has an outer shape formed by a boxy device main body18of approximately rectangular parallelepiped shape, and a tilt lever19serving as the finger-hooking portion extended to the front surface1zside of the endoscope1so as to form a plane from a corner portion of one side of the device main body18.

On an upper surface of the device main body18configuring a disposition surface4hof an exterior member4gto be described later (as for both of these, seeFIGS. 7 and 9) of the video display device4, provided are a monitor portion21as a display portion for displaying an endoscope image picked up by the image pickup device17, a power display lamp23to be turned on when the power is turned on, and a power switch22for turning on and off a power source of the endoscope main body1b, as shown inFIG. 4.

Furthermore, on an upper surface of the tilt lever19configuring the disposition surface4hof the exterior member4gof the video display device4, provided are a still image recording changeover switch24and a moving image recording changeover switch25. The still image recording switch24is turned on when setting the endoscope image to be recorded as a still image, and the moving image changeover switch25is turned on when setting the endoscope image to be recorded as a moving image.

Note that, the still image recording changeover switch24and the moving image recording changeover switch25may be provided on the upper surface of the device main body18. Also, the power switch22may be provided on the upper surface of the tilt lever19.

In addition, on the upper surface of the device main body18or the tilt lever19, the above-described image recording switch15aand the image reproduction switch15bmay be provided.

As shown inFIG. 1, the device main body18has on a surface of the front surface1zside of the endoscope1an openable/closable lid body26for containing and detaching a battery34and a memory medium such as a memory card, not shown, into and from a containing portion not shown.

The components disposed in the device main body18have watertight structure, and the openable/closable lid body26, in particular, includes a fixing nail26aand a buckle lever26bto obtain secure watertight structure with respect to the containing portion of the device main body18.

The video display device4is configured such that, in a connecting portion120to be described later (seeFIG. 7) between the device main body18and the operation portion main body9, the monitor portion21is rotatable, as shown inFIG. 3, between a position where the display surface of the monitor portion faces the upper direction in the drawing which is an insertion axis direction J of the insertion portion2and a position where the display surface of the monitor portion faces the front surface1zside of the endoscope1which is a direction P approximately orthogonal to the insertion axis direction, by means of a rotational shaft55to be described later provided penetrating in right/left direction inFIG. 1.

The video display device4is rotated by rotating the tilt lever19by a cushion of the thumb T of the left hand of the operator gripping the grasping portion8, for example. Note that a plurality of slip stoppers20as convex portions (seeFIG. 3) are formed on the upper surface of the tilt lever19.

Next, a configuration in which the LED16is disposed in the operation portion3will be described with reference toFIG. 5.FIG. 5is a partially enlarged cross-sectional view schematically showing an internal configuration of the operation portion of the endoscope inFIG. 1.

As shown inFIG. 5, inside of the grasping portion8of the operation portion3, which is watertightly occluded by an exterior member3g, metal frames80, which are plate-like heat transfer frames formed in a semi-cylinder shape, are extendedly provided so as to face each other in the insertion axis direction J along the exterior member3gon the front surface1zside and the rear surface1hside of the endoscope1. Each of the metal frames80is respectively fixed with a screw95to each of interposing plates81fixed to the inner surface of the exterior member3g.

In addition, in a space between the metal frames80facing each other, the suction duct100, an image guide38, the bending operation wire60, and a light guide bundle35formed by biding light guide fibers are extendedly provided, and in addition, a cable30sextended from a power supply control circuit30(seeFIG. 6) to be described later to the LED16is provided in order to transmit the electric power supplied from the battery34to the LED16.

Furthermore, in the space between the metal frames80facing each other, an illumination means fixing member70serving as an illumination portion fixing member is fixed with screws90serving as mounting members.

Note that the illumination means fixing member has been conventionally used as a member for fixing the bending operation wire60by butting a coil covered on an outer circumference of the bending operation wire60against the member. The illumination means fixing member70according to the present embodiment is formed larger than the conventionally employed illumination means fixing member.

The illumination means fixing member70is formed with a solid and approximate cylinder-shaped member, as shown inFIG. 5, and is made of heat transfer member such as aluminum or brass, for example. In addition, the illumination means fixing member70includes through holes70ato70e(through holes70cand70eare not shown) formed along the insertion axis direction J. Note that, in the illumination means fixing member70, only a portion between the through holes70aand70bmay be formed of the heat transfer member.

The through hole70aconfigures a fluid duct insertion hole of the present invention, and the suction duct100which is a fluid duct extended in the grasping portion8is inserted into the through hole70asuch that a part of the suction duct100closely contacts the inner circumference of the through hole70a.

The through hole70bconfigures an illumination means disposing space serving as an illumination portion disposing space of the present invention, and an LED base76to be described later, the light guide bundle35, and the cable30sare inserted into the through hole70b.

To be concrete, the LED base76made of metal, to which the LED16is fixed such that the LED16butts against one end surface of the light guide bundle35, is inserted into the through hole70b. Note that, on the LED base76, a substrate and the like not shown, to which an end portion of the cable30sis connected, are disposed. In addition, the LED base76is fixed so as to closely contact the inner circumference of the through hole70b.

The through hole70chas the image guide38inserted therethtough. The through holes70d,70ehave the bending operation wire60inserted therethrough, with the above-described coil of the bending operation wire60butted thereagainst.

Next, description will be made on the internal configuration of the endoscope1which is mainly configured by the image pickup system and the illumination optical system, with reference toFIGS. 6 to 9.FIG. 6is a view schematically showing an internal configuration of the endoscope inFIG. 1, mainly illustrating an image pickup system and an illumination optical system, andFIG. 7is a cross-sectional view of a part of the operation portion and a video display device taken along the VII-VII line ofFIG. 3.

FIG. 8is a cross-sectional view of the video display device taken along the VIII-VIII line ofFIG. 7, andFIG. 9is a cross-sectional view of the video display device taken along the IX-IX line ofFIG. 8.

As shown inFIG. 6, in an interior portion4iwatertightly occluded by the exterior member4gserving as a frame body of the video display device4, in addition to the above-described monitor portion21and the battery34, provided are the power supply control circuit30serving as the light source driving circuit, the recording control circuit31serving as recording means configuring a recording section, a display device control circuit32, and an image pickup device control circuit33serving as image pickup means configuring an image pickup section.

On the disposition surface4hof the exterior member4gof the video display device4, a depression4mhaving a concave shape is formed such that the size of the plane is approximately equal to that of the above-described monitor portion21, as shown inFIG. 9.

The depression4mhas fitted thereinto a display device such as a liquid crystal display (hereinafter referred to as an LCD)21L which is a display member and a transparent cover member21C which covers a display surface21LH of the LCD21L. Note that the LCD21L and the cover member21C configure the monitor portion21. That is, the exterior member4gholds the monitor portion21.

Furthermore, as shown inFIG. 6, the above-described light guide bundle35and the image guide38are extended from the insertion portion2to the grasping portion8of the operation portion3inside the endoscope1.

From the distal end portion5to the operation portion main body9, the above-described suction duct100is extended, and in addition, from the bending portion6to the operation portion main body9, the above-described bending operation wire60(not shown inFIG. 6) is extended.

Illumination light from the LED16provided in the grasping portion8is irradiated on the one end surface of the light guide bundle35positioned so as to butt against the LED16.

Then, the illumination light is transmitted from the one end surface of the light guide bundle35to the other end surface thereof positioned at the distal end portion5, and thereafter, irradiated from an illumination lens36provided on a distal end side of the other end surface of the light guide bundle35on a predetermined range in a direction of region to be inspected50in the body cavity.

A reflected light image from the region to be inspected50to which the illumination light is irradiated is transmitted to one end of the image guide38after being incident on the other end of the image guide38via an image pickup lens40and an objective lens39provided to the distal end portion5. After that, the reflected light image led from the one end of the image guide38goes through a condenser lens37provided in the operation portion main body9to be formed on the image pickup device17.

As shown inFIG. 9, the power supply control circuit30is provided in the interior portion4iof the video display device4so as to be positioned in a plane space on a side closer to a rear surface4bof the exterior member4gthan the monitor portion21but not to contact the rear surface4b. Note that the rear surface4bof the exterior member4gconfigures a heat radiation portion for radiating heat generated by the power supply control circuit30.

The power supply control circuit30receives the electric power supplied from the battery34to output corresponding driving powers to the LED16, the image pickup device17, the monitor portion21, the recording control circuit31, the display device control circuit32, and the image pickup device control circuit33, respectively.

Note that the driving electric powers are outputted to the image pickup device17and the LED16provided in the operation portion3, via the cables30s,30minserted in the space55iin the metal rotational shaft55in the connecting portion120between the operation portion3and the video display device4, as shown inFIGS. 7 and 8. Since the cables30s,30mare inserted in the space55iin the metal rotational shaft55, radiation noises from the cables30s,30mare shielded by the rotational shaft55.

The driving electric powers are outputted to the recording control circuit31, the display device control circuit32, and the image pickup device control circuit33, in the interior portion4iof the video display device4, via a cable30v.

The power supply control circuit30is configured to include the above-described power switch22, and turned on and off by the power switch22. Note that the battery34is configured of a secondary battery which can be repeatedly used by charging.

The image of the region to be inspected50picked up by the image pickup device17is outputted from the image pickup device17to the image pickup device control circuit33via an image pickup cable58having one end connected to the image pickup device17and the other end connected to the image pickup device control circuit33.

Note that, also the image pickup cable58is inserted in the space55iin the rotational shaft55in the connecting portion120. In addition, the image pickup cable58has a middle part held by a pair of cramp members56provided so as to face each other in the vicinity of the rotational shaft55in the operation portion main body9and the video display device4, as shown inFIG. 7to prevent the connection by soldering with the image pickup device17and the image pickup device control circuit33from detaching, even if the image pickup cable58is twisted by the rotational movement of the video display device4.

The image pickup device control circuit33converts the image of the region to be inspected50picked up by the image pickup device17into a signal to output the signal to the recording control circuit31and the display device control circuit32.

A recording medium such as an XD picture card is detachably attached to the recording control circuit31. To the recording control circuit31, supplied are input signals from the image switch15(seeFIG. 2) provided in the operation portion main body9, and the still image recording changeover switch24and the moving image recording changeover switch25provided in the video display device4(as for both of the switches, seeFIG. 1).

In response to the input signals from these various kinds of switches, the recording control circuit31performs controls such as recording the signal of the endoscope image as a still image or a moving image, and reproducing and stopping the recorded image. That is, the recording control circuit31stores in a recording medium the image of the region to be inspected50converted into a signal by the image pickup device control circuit33, and outputs the stored signal to the display device control circuit32in response to instruction signals such as reproduction and stop by the image reproduction switch15b.

The display device control circuit32visualizes the signal from the recording control circuit31or the image pickup device control circuit33to cause the monitor portion21to display the endoscope image. In addition, the recording control circuit31, in response to the signals inputted from the various kinds of switches15,24, and25, feeds to the power supply control circuit30an instruction signal for supplying electric power to the LED16, the image pickup device17, and image pickup device control circuit33.

In the endoscope1configured as such, when the power switch22is turned on, electric power is supplied from the power supply control circuit30of the video display device4. After the display device4of the endoscope1is activated in an image reproduction mode, an image recorded in the recording control circuit31is displayed on the monitor potion21. Note that, in this state, electric power is not supplied to the LED16and the image pickup device17from the power supply control circuit30.

After that, when the operator turns on the still image recording changeover switch24and the video display device4of the endoscope1becomes a still image recording standby state, electric power is supplied also to the LED16and the image pickup device17from the power supply control circuit30. This allows the image under observation to be transmitted from the image pickup device17in the following order to the image pickup device control circuit33, the display device control circuit32, and the monitor portion21, to be displayed in real time on the monitor portion21.

In a case of recording a still image in this state, if the operator turns on the image recording switch15a, an image signal is inputted to the recording control circuit31from the image pickup device control circuit33, and the still image is recorded in an internal memory as a recording medium of the recording control circuit31. Note that, after the recording, the image under observation is automatically displayed again on the monitor portion21.

After that, when the operator turns on the image reproduction switch15b, an image signal is outputted to the display device control circuit32from the recording control circuit31, and the recorded still image is displayed on the monitor portion21. Then, when the operator turns off the image reproduction switch15b, the image under observation is displayed on the monitor portion21instead of the still image.

In addition, if the operator turns on the moving image recording changeover switch25in this state, the video display device4of the endoscope1becomes a moving image recording standby state. Also in this case, the image under observation is transmitted from the image pickup device17in the following order to the image pickup device control circuit33, the display device control circuit32, and the monitor portion21to be displayed in real time on the monitor portion21.

In a case of recording a moving image in this state, if the operator turns on the image recording switch15a, the moving image is recorded in the internal memory of the recording control circuit31similarly as described above.

During the recording of the moving image, either the image pickup device control circuit33or the recording control circuit31outputs the image signal in real time to the display device control circuit32, and the image under observation is displayed in real time on the monitor portion21.

After that, if the operator turns off the image recording switch15a, the recording is stopped, and the image under observation is displayed on the monitor portion21instead of the moving image. In a case of reproducing the moving image subsequently, if the operator turns on the image reproduction switch15b, a control of moving image reproduction is performed similarly as that of the still image reproduction. When the moving image reproduction is finished, similar control of when the above-described still image reproduction is finished is performed, and thereafter the video display device4of the endoscope1returns to the state at the time of the activation.

Next, actions of the present embodiment configured as such will be described. Note that, the following description will be made on the actions of the heat radiation methods of the LED16in the operation portion3and of the power supply control circuit30in the video display device4.

First, the power switch22of the endoscope1is turned on. After that, when the still image recording changeover switch24or the moving image recording changeover switch25is turned on, electric power is supplied from the power supply control circuit30of the video display device4to the LED16via the cable30s. As a result, the LED16starts emitting light, and the illumination light emitted from the LED16is irradiated from the illumination lens36, via the light guide bundle35, to a predetermined range in a direction of region to be inspected50in the body cavity.

At this time, heat N is radiated from the LED16with the light emission thereof, in the through hole70bof the illumination means fixing member70fixed between the two metal frames80. Since the LED base76and the illumination means fixing member70are made of metal member and heat transfer member, respectively, the heat N of the LED16radiated in the through hole70bis transferred, via the LED base76and the illumination means fixing member70, to the suction duct100with which a part of the outer circumference of the through hole70aof the illumination means fixing member70(seeFIG. 5) comes into close contact.

Then, the suction button11a is turned on and the suction device connected to the suction base11is driven, which allows the fluid such as body fluid or phlegm sucked from inside of the body cavity to be flown in the flow path inside of the suction duct100. Therefore, the heat N radiated from the LED16is absorbed by the fluid flowing in the flow path inside of the suction duct100and discharged to the outside of the endoscope1together with the fluid from the suction base11.

That is, the heat N is discharged to the outside of the endoscope1from the suction base11provided on the rear surface1hside of the endoscope1, which is in the direction away from the operator who is at the front surface1zside of the endoscope1.

In addition, when the power switch22of the endoscope1is turned on, the heat N is radiated also from the power supply control circuit30with the driving thereof. Since the power supply control circuit30is provided in the interior portion4ioccluded by the exterior member4gof the video display device4so as to be located on a rear surface side of the monitor portion21observed by the operator, in particular, on the rear surface4bside of the exterior member4g, the heat N, as shown inFIG. 9, is discharged in a direction away from the operator, from the rear surface4bconfiguring the heat radiation portion away from the operator.

Note that, this is also true when the monitor portion21in the video display device4is at a position where the display surface of the monitor portion faces upper side which is the insertion axis direction J of the insertion portion2, or even when the monitor portion21is at a position where the display surface thereof faces the front surface1zside of the endoscope1which is the direction P approximately orthogonal to the insertion axis direction J.

Thus, in the present embodiment, when the LED16is provided in the space watertightly covered by the exterior member3gin the grasping portion8of the operation portion3, the illumination means fixing member70made of heat transfer member is fixed between the two metal frames80fixed to the exterior member3g. The illumination means fixing member70has through holes70a,70bformed therein, and the LED16is provided in the through hole70b, and the suction duct100is inserted in the through hole70a.

In addition, the power supply control circuit30is provided in the interior portion4icovered with the exterior member4gof the video display device4, and the power supply control circuit30is disposed in the interior portion4icloser to the rear surface4bside of the exterior member4gthan the monitor portion21.

With such a configuration, when the LED16generates heat with the light emission thereof, the heat N is transmitted to the suction duct100through the heat conduction of the illumination means fixing member70, then radiated, via the suction duct100, from the suction base11provided on the rear surface1hside of the endoscope1away from the operator who is at the front surface1zside of the endoscope1. Therefore, the heat N of the LED16is surely discharged in the direction avoiding the operator.

In addition, when the power supply control circuit30generates heat with the driving thereof, the heat N is radiated from the rear surface4bof the exterior member4gof the video display device4which is on the rear surface side of the monitor portion21to the rear surface1hside of the endoscope1. Therefore, the heat N from the power supply control circuit30is surely discharged in the direction avoiding the operator who is at the front surface1zside of the endoscope1and observing the monitor portion21.

Moreover, the LED16and the power supply control circuit30are provided in the operation portion3and the video display device4, respectively. That is, the LED16and the power supply control circuit30are provided in positions away from each other in the endoscope1, so that there are no areas in the endoscope1which is locally heated by the heat radiation from the LED16and the power supply control circuit30. That is, dispersion efficiency of the heat N is increased in the endoscope1, thereby preventing the operator from feeling discomfort by the locally radiated heat N.

Thus, it is possible to provide the endoscope1having the configuration in which not only the heat from the light source but also the heat from the power supply control circuit30can be surely radiated in a direction other than the direction of the operator who uses the endoscope1.

Note that a modification example will be shown.FIG. 10is a cross-sectional view showing a modification example of internal configurations of a part of the operation portion and the video display device.

In the present embodiment, the power supply control circuit30is provided on the rear surface side of the monitor portion21in the interior portion4iof the video display device4.

However, the present invention is not limited to the above, the power supply control circuit30may be provided in such a manner as to be fixed to the rear surface4bof the exterior member4gin the interior portion4i, as long as being located on the rear surface side of the monitor portion21, as shown inFIG. 10.

In this case, since the power supply control circuit30is fixed, there is such an inconvenience that the rear surface4bis heated to become hotter compared with the above embodiment and it is hard for the operator to touch the rear surface4b. However, except for the inconvenience, the heat N of the power supply control circuit30can be radiated from the rear surface4bin a more proactive manner than in a case of the present embodiment.

In the present embodiment, the LED16and the image pickup device17are provided in the operation portion3. However, the present invention is not limited to the same. Even when the LED16and the image pickup device17are provided in the distal end portion5of the insertion portion2, the same effect as that of the present embodiment can be obtained.

Furthermore, the present embodiment shows an example in which the power supply control circuit30and the image pickup device control circuit33are separately provided in the video display device4. However the present invention is not limited to the same, and the power supply control circuit30and the image pickup control circuit33may be integrally formed. In this case, also the heat N generated with the driving of image pickup device control circuit33can be more efficiently discharged from the rear surface4bside of the exterior member4gin the direction other than the direction of the operator.

Furthermore, in the present embodiment, the power supply control circuit30is provided in the interior portion4iof the video display device4. However the present invention is not limited to the same, and the power supply control circuit30may be provided in the operation portion3or the insertion portion2.

In this case, if an elongated heat transfer member such as a heat sink is provided in the endoscope1so as to be connected from the power supply control circuit30in the operation portion3or the insertion portion2to the rear surface4bof the video display device4by passing through the space55iof the rotational shaft55, even in a case where the power supply control circuit30is provided in the same place as the LED16, for example, the heat N of the power supply control circuit30is surely discharged, via the elongated heat transfer member, from the rear surface4bside which is the heat radiation portion of the video display device4similarly as in the present embodiment. Therefore, the same effect as that in the present embodiment can be obtained.

In addition, in the present embodiment, the fluid duct is described by taking the suction duct100as an example. However, the present invention is not limited to the same. In a case where a duct such as a forward water supply duct through which fluid is flown is extended in the endoscope1, and an opening of the duct located on a side of the operation portion3is oriented in a direction other than the direction of the operator, the heat N radiated from the LED16may be transferred to the duct. That is, the heat N radiated from the LED16may be transferred to any duct as long as the duct is one, through which fluid is flown, having an opening on the side of the operation portion3oriented to a direction other than the direction of the operator.

In addition, though the endoscope1is shown taking the medical endoscope as an example in the present embodiment, the similar effect can be obtained even if the present embodiment is applied to an industrial endoscope.