JP5607113B2 - Endoscope - Google Patents

Description

  In the present invention, at least one lens in an objective lens group for observing a subject constitutes a movable lens that is movable with respect to the optical axis direction of the objective lens group, so that the optical characteristics of the objective lens group can be varied. Regarding mirrors.

  In recent years, endoscopes are widely used in the medical field and the industrial field. The endoscope can observe the inside of the duct by inserting an elongated insertion portion into the duct.

  In addition, an endoscope, for example, an objective optical system composed of a plurality of objective lens groups for observing the inside of a duct, or a solid-state imaging device such as a CCD, is disposed in the distal end portion in the insertion direction of an insertion portion of an electronic endoscope. An element is generally provided, and an electronic endoscope is configured such that an image of an observation site in a duct formed by an objective optical system is captured by a solid-state image sensor.

  Furthermore, by making at least one of the plurality of objective lens groups in the objective optical system a movable lens that is movable with respect to the optical axis direction of the objective optical system, the movable lens is moved in the optical axis direction. The optical depth of the objective optical system with respect to the observation part, the optical characteristics such as the imaging magnification and the viewing angle can be varied, for example, a structure capable of normal observation to magnified observation with respect to the observation part of 1 to 100 times is provided. Zoom endoscopes are also well known. If observation is performed using a zoom endoscope, for example, in the case of a medical endoscope, it is possible to observe the structure of the mucous membrane and capillaries at the observation site in the body cavity.

  Here, various mechanisms for moving the moving lens as described above in the optical axis direction have been proposed. For example, in Patent Document 1, an endoscope includes a lens frame that holds a moving lens, a protruding portion that protrudes from the lens frame in the radial direction of the moving lens, and a tip in the optical axis direction at the protruding portion. A wire frame that is fixed and has a rear end that is fixed to a focus adjustment lever provided in an operation unit of the endoscope, and pulls and loosens the wire in accordance with the operation of the focus adjustment lever. That is, a configuration for moving the moving lens in the optical axis direction is disclosed.

  In Patent Document 2, an endoscope has an imaging optical frame that holds a focal lens group corresponding to a moving lens, and one end is fixed to the rear end in the optical axis direction of the imaging optical frame, and the other end is a focal lens. Two shape memory alloys that can be expanded and contracted in the optical axis direction, which are fixed to an imaging element frame that holds an imaging element positioned behind the group in the optical axis direction, and the two shape memory alloys that expand and contract in the optical axis direction Thus, a configuration is disclosed that includes an energization mechanism for simultaneously energizing or de-energizing two shape memory alloys. The focusing lens group can be moved in the optical axis direction in accordance with the energization of the two shape memory alloys by the energization mechanism and the synchronized expansion and contraction of the two shape memory alloys in the optical axis direction in response to the non-energization.

  In addition, a configuration in which the lens frame that holds the moving lens is moved in the optical axis direction using an electrostatic actuator, or a configuration in which the lens frame that holds the moving lens is moved in the optical axis direction using a linear motion cam Is well known.

JP 2000-292712 A JP 2004-129950 A

  By the way, in recent years, in addition to a zoom endoscope capable of normal observation and magnified observation up to 1 to 100 times with respect to an observation site, for example, a medical endoscope, the cell level of a tissue in an observation site in a body cavity One objective optical system consisting of a plurality of objective lens groups, from normal observation to super-magnification observation (hereinafter referred to as ECS (Endo Cyto Scope) observation) from 1 to 500 times that can be observed. Zoom endoscopes that can be performed in a system are also well known.

  According to an endoscope that can perform ECS observation, it is not necessary to collect tissue cells by surgery or excision using a treatment tool of an endoscope when performing tissue observation. Can be reduced.

  Here, in order to perform ECS observation with one objective optical system composed of a plurality of objective lens groups, the moving amount of the moving lens is set to a small amount, for example, for the purpose of downsizing the distal end portion of the insertion portion of the endoscope. It must be set in the range of 0.6 mm to 1.0 mm.

  However, in the configuration in which the lens frame that holds the moving lens with the wire is moved as in the configuration disclosed in Patent Document 1, considering that the moving amount of the moving lens is very small, the focus adjustment lever is small. The moving lens must be moved from 1 to 500 times by a stroke operation. Therefore, in this configuration, since the operation of the focus adjustment lever becomes sensitive, it is difficult to adjust the moving lens by a small amount, and the observer's desired position, for example, 50 × observation, 100 × observation, 200 × There is a problem that skill is required to position the moving lens at a position where observation and 300-times observation are performed.

  Further, as in the configuration disclosed in Patent Document 2, in the configuration in which the focus lens group corresponding to the moving lens is moved using the expansion and contraction of the two shape memory alloys in the optical axis direction, the two shape memory alloys are used. By energizing and de-energizing the two shape memory alloys, the two shape memory alloys are synchronized and contracted at the same time, so it can be easily moved to 1x and 500x, but the observer's desired position, for example, 50x, 100x In order to move the focusing lens group to a position such as 200 times and 300 times with high accuracy, there is a problem that energization control is difficult.

  Furthermore, in the configuration using the electrostatic actuator and the linear motion cam, the mechanism for moving the moving lens is increased in size, so that there is a problem that the diameter of the tip is increased.

  The object of the present invention has been made in view of the above problems, and easily moves the moving lens to a desired position of an observer with a simple structure without increasing the diameter of the distal end of the insertion portion. It is in providing the endoscope which comprises the structure which can be moved.

In order to achieve the above object, an endoscope according to an aspect of the present invention forms a moving lens in which a predetermined lens in an objective lens group for observing a subject is movable with respect to the optical axis direction of the objective lens group. In the endoscope in which the observation magnification by the objective lens group can be varied, the objective lens group is configured, the first moving lens is configured to vary the observation magnification below a predetermined observation magnification, and the objective lens group is configured A second moving lens that varies the observation magnification beyond the predetermined observation magnification; a first moving lens frame that holds the first moving lens and is movable in the optical axis direction; a second movable lens frame which is movable in the optical axis direction with holding the second movable lens, so as to vary the said observation magnification below the predetermined observation magnification, the first movable lens frame The first moving member is moved within the first moving range by the first operation, and the second moving lens frame is moved per unit time so as to vary the observation magnification beyond the predetermined observation magnification. And a second moving member that moves within a second moving range by a second operation that is smaller than the first operation.

  According to the present invention, an endoscope having a configuration capable of easily moving a moving lens to a desired position of an observer with a simple structure without increasing the diameter of the distal end portion of the insertion portion. Can be provided.

The perspective view which shows the external appearance of the endoscope apparatus which comprises the endoscope of 1st Embodiment. Sectional drawing which shows the outline of a structure of the imaging unit provided in the front-end | tip part of the insertion part of the endoscope of FIG. The perspective view which expands and shows the moving lens frame in FIG. 2 with a moving lens The perspective view which expands and shows the 2nd fixed lens frame in FIG. The bottom view which looked at the 2nd fixed lens frame of Drawing 4 from the lower part FIG. 2 is a partial cross-sectional view of the imaging unit showing the movement of the moving lens frame in FIG. 2. 2 is a partial cross-sectional view of the imaging unit showing that the moving lens frame in FIG. 2 is moved by a wire and the moving amount by which the moving lens frame can move is different depending on the moving member. 2 is a chart showing a modification in which the moving amount of the moving lens frame in FIG. 2 per unit time varies depending on the moving member. 2 is a partial cross-sectional view of an imaging unit showing a modification in which two moving lens frames in FIG. 2 are provided and each moving lens frame is moved by a different moving member. FIG. 9 is a partial cross-sectional view of an imaging unit showing a modification in which the two moving lenses in FIG. 9 are moved in conjunction with each other. Partial sectional view of the imaging unit in the endoscope showing the second embodiment The figure which shows the fragmentary sectional view of the imaging unit in the endoscope which shows 3rd Embodiment with each pulling and relaxation apparatus of a wire and a cylindrical member Sectional drawing which shows the outline of a structure of the imaging unit provided in the front-end | tip part of the insertion part of the endoscope which shows 4th Embodiment. The fragmentary sectional view which shows the modification of the moving member with respect to the accommodating member of FIG. 13, and the protrusion part of a moving lens frame The fragmentary sectional view which shows the example which provided the element frame to which the solid-state image sensor in an imaging unit is fixed to the length which covers the outer periphery of the connection part of the signal cable of the board | substrate connected to the solid-state image sensor FIG. 15 is a partial sectional view showing an example in which an inward flange portion is provided at the rear end in the optical axis direction of the element frame of FIG. Partial sectional view showing an example in which the imaging surface of the imaging device and the substrate connected to the imaging device are positioned in parallel with the optical axis in the distal end portion of the endoscope Sectional drawing which shows the outline of a structure of the imaging unit provided in the front-end | tip part of the insertion part of the endoscope which shows this Embodiment Sectional view along line XIX-XIX in FIG. The perspective view which expands and shows the ring-shaped frame of FIG. 18 is a partial sectional view showing the position of the moving lens in FIG. 18 in normal observation (1 ×). 18 is a partial cross-sectional view showing the position of the moving lens in FIG. 18 between normal observation and magnified observation (1 to 100 times). 18 is a partial sectional view showing the position of the moving lens in FIG. 18 during magnified observation (100 ×). 18 is a partial cross-sectional view showing the position of the moving lens in FIG. 18 between magnification observation and ECS observation (100 to 500 times). Partial sectional view showing the position of the moving lens of FIG. 18 in ECS observation (500 times)

  Embodiments of the present invention will be described below with reference to the drawings. In the embodiment described below, the endoscope will be described by taking a medical endoscope as an example.

(First embodiment)
FIG. 1 is a perspective view illustrating an appearance of an endoscope apparatus including the endoscope according to the first embodiment.
As shown in FIG. 1, the endoscope device 126 includes an endoscope 116 and a peripheral device 136. The endoscope 116 is mainly composed of an operation unit 104, an insertion unit 101, and a universal cord 117.

  The peripheral device 136 includes a light source device 124, a video processor 123, a connection cable 122, a keyboard 224, and a monitor 125, which are arranged on a frame 226. Further, the endoscope 116 and the peripheral device 136 having such a configuration are connected to each other by a connector 118.

  A bending operation knob 105, a zoom lever 106, an air / water supply operation button 107, a suction operation button 108, and a treatment instrument insertion port 114 are disposed on the operation unit 104 of the endoscope 116.

  The insertion portion 101 of the endoscope 116 includes a distal end portion 109, a bending portion 102, and a flexible tube portion 103. The bending portion 102 is bent by a bending operation knob 105 provided in the operation portion 104, and is disposed between the distal end portion 109 and the flexible tube portion 103.

  The objective lens 1 positioned on the distal end side in the insertion direction of an objective lens group 100 (both see FIG. 2) in the imaging unit 300 described later on the distal end surface of the distal end portion 109 in the insertion direction (hereinafter simply referred to as the distal end side). (See FIG. 2) is provided.

  Further, a nozzle 111 for cleaning the surface of the objective lens 1 by spraying a fluid such as water or air onto the surface of the objective lens 1 on the distal end surface of the distal end portion 109, an illumination window 112, and a treatment instrument insertion path (not shown). The tip opening 113 of the suction pipe that also serves as the outlet is disposed.

  Further, an imaging device 320 (both see FIG. 2) in the imaging unit 300 described later is built in the distal end portion 109.

  Gas and liquid are selectively ejected from the nozzle 111 by the button operation of the air / water supply operation button 107 of the operation unit 104. A treatment instrument provided from the treatment instrument insertion port 114 to the distal end opening 113 in the insertion section 101 by operating the suction operation button 108 of the operation section 104 from the distal opening 113 of the suction conduit that also serves as the treatment instrument insertion passage. Mucus and the like in the body cavity are selectively collected through the suction conduit that also serves as the insertion passage.

  A connector 118 is provided at the distal end of the universal cord 117 of the endoscope 116, and this connector 118 is connected to the light source device 124 of the peripheral device 136. The connector 118 is provided with a light guide base (not shown) that constitutes an end of a light guide (not shown), an electrical contact portion to which an end of a signal cable 17 (see FIG. 2) described later is connected, and the like. Further, a connection cable 122 for electrically connecting the light source device 124 to the video processor 123 is connected to the connector 118.

  The light guide is inserted from the above-described light guide base of the connector 118 through the universal cord 117, the operation unit 104, and the insertion unit 101 to a position close to the illumination window 112 in the distal end portion 109. The illumination light from the light source device 124 is sent to the illumination window 112, and the illumination light is spread and irradiated into the body cavity via the illumination window 112.

  In addition, the signal cable 17 is connected to a later-described substrate 14 (see FIG. 2) that is electrically connected to a later-described solid-state image sensor 13 of the imaging device 320 in the distal end portion 109, and the operation unit 104. The electric signal of the image picked up by the solid-state image pickup device 13 of the image pickup device 320 is transmitted to the video processor 123 through the inside and the universal cord 117 to the above-described electric contact portion in the connector 118. It is.

  Next, the configuration of the imaging unit 300 provided in the distal end portion 109 will be described with reference to FIGS. 2 is a cross-sectional view showing an outline of the configuration of the imaging unit provided in the distal end portion of the insertion portion of the endoscope of FIG. 1, and FIG. 3 is an enlarged view of the moving lens frame in FIG. 2 together with the moving lens. 4 is an enlarged perspective view showing the second fixed lens frame in FIG. 2, FIG. 5 is a bottom view of the second fixed lens frame in FIG. 4 viewed from below, and FIG. It is a fragmentary sectional view of the image pick-up unit which shows the movement of the moving lens frame.

  As shown in FIG. 2, the imaging unit 300 includes an objective lens group 100 including a plurality of objective lenses 1, 3, 4, 5, 8, 9, 10, a first fixed lens frame 26, and a lens holder 6. A moving lens frame 180, a second fixed lens frame 27, moving members 29 and 30 for moving the moving lens frame 180 in the optical axis direction K by a plurality of different operations, a ring-shaped frame 18, and an actuator protection frame 19. The element frame 28, the protective frame 15, the heat shrinkable tube 16, and the thermoplastic resin 149 constitute main parts.

  The first fixed lens frame 26 holds the objective lenses 1 and 3 in the objective lens group 100 at the front end side in the optical axis direction K of the objective lens group 100 (hereinafter simply referred to as the front end side), and the objective lens 4. 5 is a frame that holds 5 on the rear end side in the optical axis direction K (hereinafter simply referred to as the rear end side).

  A diaphragm 2 is provided between the objective lens 1 and the objective lens 3. Further, the objective lens 5 is held via a lens holder 6 on the rear end side of the first fixed lens frame 26. Further, the lens holder 6 is also provided with a diaphragm 7.

  The inner periphery on the front end side of the second fixed lens frame 27 having a predetermined length in the optical axis direction K is fitted and fixed to the outer periphery on the rear end side of the first fixed lens frame 26.

  Further, the inner periphery of the ring-shaped frame 18 is fitted and fixed to the outer periphery on the front end side of the second fixed lens frame 27, and the outer periphery of the ring-shaped frame 18 and the rear end side of the second fixed lens frame 27. The inner periphery of the actuator protection frame 19 that covers the second fixed lens frame 27 along the optical axis direction L is fitted and fixed to the outer periphery of the formed outward flange portion 27f.

  Further, the second fixed lens frame 27 holds the objective lenses 9 and 10 in the objective lens group 100 on the inner periphery on the rear end side of the second fixed lens frame 27. Further, the outer periphery on the front end side of the element frame 28 is fitted and fixed to the inner periphery of the rear end of the second fixed lens frame 27.

  The inner periphery on the front end side of the protective frame 15 having a predetermined length in the optical axis direction K is fitted and fixed to the outer periphery on the rear end side of the element frame 28. A heat shrinkable tube 16 that covers the protective frame 15 is fixed to the outer periphery of the protective frame 15. The rear end side of the heat shrinkable tube 45 is fixed to the front end side of the signal cable 17.

  The imaging device 320 is disposed together with the thermoplastic resin 149 in an airtight space closed by the protective frame 15 and the heat shrinkable tube 16 behind the objective lens group 100 in the optical axis direction K (hereinafter simply referred to as the rear). Has been.

  The imaging device 320 includes a solid-state imaging device 13, a cover glass 12, a centering cover glass 11, a substrate 14 formed of a laminated substrate or a rigid substrate, and a signal cable 17. .

  A cover glass 12 that protects the image pickup surface is attached to the image pickup surface of the solid-state image pickup device 13, and a centering cover glass 11 having an outer shape larger than that of the cover glass 12 is provided on the front surface side of the cover glass 12. It is stuck. The centering cover glass 11 has an outer periphery fixed to the inner periphery of the element frame 28, and an outer edge portion of the front end surface is an inward flange portion 28f formed at a midway position in the optical axis direction K of the element frame 28. It is fixed to the rear end face.

  In addition, a substrate 14 is electrically connected to the solid-state imaging element 13, and lead wires extending from the signal cable 17 are electrically connected to the substrate 14.

  As shown in FIGS. 4 and 5, respectively, slits 27s along the optical axis direction K are formed above and below the second fixed lens frame 27 in FIG. 2, and a moving lens is formed in the two slits 27s. Two protruding portions 180 t shown in FIG. 3 that protrude in the radial direction of the moving lens 8 in the frame 180 are slid in the optical axis direction K. The moving lens frame 180 holds the moving lens 8 that can move forward and backward in the optical axis direction K in the objective lens group 100.

  As a result, the movable lens frame 180 is movable forward and backward in the optical axis direction K, with the two protruding portions 180t being guided by the slits 27s. In other words, the movable lens 8 held by the movable lens frame 180 is movable back and forth in the optical axis direction K within the second fixed lens frame 27.

  Further, the portions of the projecting portions 180 t of the moving lens frame 180 projecting in the vertical direction in FIG. 2 of the second fixed lens frame 27 from the slits 27 s are the outer periphery of the second fixed lens frame 27 and the ring-shaped frame 18. It is located in a space 190 formed by the rear end surface, the front end surface of the outward flange portion 27 f, and the inner peripheral surface of the actuator protection frame 19. Therefore, when the movable lens frame 180 moves forward and backward in the optical axis direction K, each protrusion 180 t can also move forward and backward in the optical axis direction K in the space 190.

  The distal ends of the springs 21A and 21B constituting the moving members 29 and 30 are fixed to the rear end surfaces of the projecting portions 180t, and the rear ends of the springs 21A and 21B are connected to the distal end surfaces of the outward flange portions 27f. ing. That is, the springs 21A and 21B are provided along the optical axis direction K between the respective projecting portions 180t and the outward flange portion 27f. Each spring 21A, 21B moves the movable lens frame 180 to the tip side by urging each protrusion 180t to the tip side.

  In addition, each projecting portion 180t and outward flange portion 27f are formed with through-holes 180h and 27h that penetrate in the optical axis direction K and face each other. The shape memory alloys 22A and 22B constituting the moving members 29 and 30 extending along the optical axis direction K are inserted into the through holes 180h and 27h, respectively, and the tips of the shape memory alloys 22A and 22B are The fixing member 20 is fixed to the front end surface of each protrusion 180t.

  Further, on the rear end side of each shape memory alloy 22A, 22B, a power line for supplying current to the power source side 22p of the shape memory alloy 22A, 22B in accordance with the operation of the zoom lever 106 (see FIG. 1) of the operation unit 104. 24A and 24B are electrically connected, and GND lines 25A and 25B for supplying a current to the GND side 22m of the shape memory alloys 22A and 22B are electrically connected.

  The power lines 24A and 24B and the GND lines 25A and 25B are connected to the video processor 123 via the insertion unit 101, the operation unit 104, the universal cord 117, the connector 118, and the connection cable 122. The control device (not shown) controls the amount of current supplied to the power source side 22p and the GND side 22m of the shape memory alloys 22A and 22B by detecting the resistance value accompanying the heat generation of the shape memory alloys 22A and 22B.

  The shape memory alloys 22A and 22B contract in the optical axis direction K while generating heat by supplying current. That is, when an electric current is supplied to the shape memory alloy 22A, the moving lens frame 180 in which the tip of the shape memory alloy 22A is fixed to each projecting portion 180t constitutes a plurality of different operations of the shape memory alloy 22A. With the first contraction that is the operation, as shown in FIG. 6, the rear end side of the optical axis direction K is defined by the bias of the springs 21A and 21B to which no current is supplied to the shape memory alloy 22A. From the position P1, it moves within the first movement range L1 against the bias of the springs 21A, 21B.

  In the present embodiment, the position P1 is defined as a position where the observation magnification for changing the optical characteristics of the objective lens group 100 is 1 time used for normal observation. Further, the moving lens frame 180 can move only within the first movement range L1 due to the first contraction of the shape memory alloy 22A, that is, the rear end of the rear end position P2 within the first movement range L1. What cannot move to the side is due to the biasing force of the springs 21A and 21B.

  In the state where the moving lens frame 180 is moved to the position P2, when the current is further supplied to the shape memory alloy 22B, the moving lens frame 180 in which the tip of the shape memory alloy 22B is fixed to each protruding portion 180t has the shape. With the second contraction, which is a second operation constituting a plurality of different operations of the memory alloy 22B, on the rear end side of the optical axis direction K, as shown in FIG. 6, from the position P2, the springs 21A, 21B It moves within the second movement range L2 against the bias. Note that the end position of the second position range L2 is defined as P3.

  That is, the moving lens frame 180 can move only within the first movement range L1 due to the biasing force of the springs 21A and 21B in the first contraction, but the second contraction in addition to the first contraction. By performing the above, the movable lens frame 180 can move within the second movement range L2 against the biasing force of the springs 21A and 21B.

  In addition, the position P2 is defined as a position at which the observation magnification of the objective lens group 100 is used for magnification observation, for example, 100 times in the present embodiment, and the position P3 is an objective in the present embodiment. It is defined that the observation magnification of the lens group 100 is a position that is used for ECS observation, for example, 500 times.

  In other words, the moving lens frame 180 is 1 ×, which is the first moving range L1 in which the observation magnification of the objective lens group 100 is lower than a set magnification, for example, 100 ×, due to the first contraction of the shape memory alloy 22A. The second moving range in which the observation magnification of the objective lens group 100 is higher than a set magnification, for example, 100 times, due to the second contraction of the shape memory alloy 22A. It moves to the rear end side so as to be located within the range of 100 times to 500 times L2.

  Further, the adjustment of the moving position of the moving lens frame 180 toward the rear end side, that is, the adjustment of the contraction amount of the shape memory alloys 22A and 22B, applies current to the shape memory alloys 22A and 22B according to the operation amount of the zoom lever 106. This is performed by controlling the amount of current supplied by the control device in the video processor 123 to be supplied.

  Furthermore, adjustment of the moving position of the moving lens frame 180 toward the front end side, that is, adjustment of the contraction amount of the shape memory alloys 22A and 22B in this case is also applied to the shape memory alloys 22A and 22B according to the operation amount of the zoom lever 106. This is performed by controlling the amount of current supplied by the control device in the video processor 123 for supplying current and urging the springs 21A and 21B toward the tip side.

  In this case, the springs 21A and 21B constitute a restricting member that restricts the moving lens frame 180 from moving out of the first moving range L1 in accordance with the first contraction of the shape memory alloy 22A. In accordance with the second contraction of the shape memory alloy 22B, a restricting member that restricts the moving lens frame 180 from moving outside the second moving range L2 is configured.

Next, the operation of the endoscope 116 of the present embodiment configured as described above will be described.
First, when examining the body cavity using the endoscope 116, the operator inserts the insertion portion 101 into the body cavity. Thereafter, the operator advances the insertion unit 101 in the body cavity to a desired observation site in the body cavity while observing with the objective lens group 100. At this time, the moving lens frame 180 and the moving lens 8 are located at a position P1 where normal observation can be performed, as shown in FIG.

  Thereafter, when the objective lens group 100 captures a desired observation site and then observes the structure of the mucous membrane and capillaries at the observation site, for example, when performing magnified observation from 1 to 100 times, the operator By operating the zoom lever 106, current is supplied to the shape memory alloy 22A from the power supply side 22p and the GND side 22m of the shape memory alloy 22A via the power supply line 24A and the GND line 25A.

  Thereafter, the shape memory alloy 22A generates heat and starts first contraction. As a result, the moving lens frame 180 and the moving lens 8 start moving within the first moving range L1 from the positions P1 to P2 against the biasing of the springs 21A and 21B toward the distal end side. That is, the moving lens frame 180 and the moving lens 8 start moving so that the observation magnification of the objective lens group 100 is in the range of 1 to 100 times.

  At this time, when the operator adjusts the operation amount of the zoom lever 106, the control device in the video processor 123 detects the resistance value of the shape memory alloy 22A and adjusts the supply amount of the current, thereby adjusting the shape memory. By adjusting the contraction rate of the alloy 22A, the moving lens frame 180 and the moving lens 8 are moved to a position of the operator's desired magnification within the first moving range L1 of 1 to 100 times and stopped.

  When the operator performs ECS observation for observing the cell level of the tissue at the observation site after the magnification observation, the operator further advances the insertion portion 101 so that the objective lens 1 is close to the observation site, and then moves the zoom lever 106. By operating, a current is supplied to the shape memory alloy 22A from the power supply side 22p and the GND side 22m of the shape memory alloy 22A via the power supply line 24A and the GND line 25A, and the moving lens frame 180 and the moving lens 8 are supplied. Is moved to a position P2 corresponding to 100 times, and further, the zoom lever 106 is further operated than in the case of performing magnified observation, so that the shape memory alloy 22B is connected to the power line 24B and the GND line 25B. Then, a current is supplied from the power supply side 22p and the GND side 22m of the shape memory alloy 22B.

  Thereafter, the shape memory alloy 22B generates heat and starts second contraction. As a result, the moving lens frame 180 and the moving lens 8 start moving within the second moving range L2 from the positions P2 to P3 against the biasing of the springs 21A and 21B toward the distal end side. That is, the moving lens frame 180 and the moving lens 8 start moving so that the observation magnification of the objective lens group 100 is in the range of 100 to 500 times.

  At this time, when the operator adjusts the operation amount of the zoom lever 106, the control device in the video processor 123 detects the resistance value of the shape memory alloy 22B and adjusts the supply amount of the current to thereby store the shape memory. By adjusting the shrinkage rate of the alloy 22B, the moving lens frame 180 and the moving lens 8 are moved to a position of the operator's desired magnification within the second moving range L2 of 100 to 500 times and stopped.

  As described above, in the present embodiment, the endoscope 116 has the moving lens frame 180 that holds the moving lens 8 that changes the observation magnification when the magnified observation is performed, the spring 21A that forms the moving member 29, and the shape. It was shown that the memory alloy 22A has a configuration that can be moved within the first movement range L1 corresponding to 1 to 100 times.

  In addition, when the endoscope 116 performs ECS observation subsequent to the enlarged observation, the moving lens frame 180 is a second equivalent to 100 to 500 times by the spring 21B and the shape memory alloy 22B constituting the moving member 30. It was shown that it has the structure which can be moved within the movement range L2.

  Further, the moving lens frame 180 does not move outside the first movement range L1 due to the contraction of the shape memory alloy 22A by the springs 21A and 21B, and as the shape memory alloy 22B contracts. It has been shown that the moving lens frame 180 does not move outside the second movement range L2.

  According to this, the moving lens frame 180 and the moving lens 8 are moved by 1 to 100 times for magnification observation by the two moving members 29 and 30 by a mechanism different from the moving lens frame 180 and the moving lens 8. The moving lens 8 can be moved from 100 times to 500 times for ECS observation at a timing different from the movement of 1 to 100 times for magnification observation.

  Therefore, even when the zoom lever 106 is operated with a small stroke, the control device in the video processor 123 can more accurately control the energization of the shape memory alloys 22A and 22B. For example, the movable lens frame 180 and the movable lens 8 can be easily and accurately moved to positions where desired magnifications such as 50 times, 100 times, 200 times, and 300 times are obtained.

  That is, if the moving lens frame 180 and the moving lens 8 are moved by one moving member as in the prior art, or if two or more moving members are moved simultaneously even if there are two or more moving members, the movement Since the movement amounts of the lens frame 180 and the moving lens 8 are very small as described above, when the zoom lever 106 is operated with a small stroke, particularly in ECS observation in which the observation magnification is increased, the lens magnification 180 is accurately moved to a desired magnification. It is difficult to move the moving lens frame 180.

  However, as in the present embodiment, two movement members can be used and two movement controls can be performed separately, and in particular, movement control dedicated to ECS observation can be performed. The 180 and the moving lens 8 can be easily and accurately moved to a position having a desired magnification.

  In addition, by moving the movable lens frame 180 and the movable lens 8 with the two moving members 29 and 30 with respect to the two protruding portions 180t, one protruding portion protruding from the moving lens frame as in the prior art. As compared with the case where a single moving member is used, the moving lens frame 180 is displaced in the radial direction as it moves, and there is no occurrence of sliding movement failure of the moving lens frame 180 or deterioration of optical characteristics. The moving lens frame 180 can be moved to the position.

  Furthermore, the moving lens frame 180 and the moving lens 8 can be accurately moved only by providing the two moving members 29 and 30 in the distal end portion 109, so that the diameter of the distal end portion 109 is not increased. .

  As described above, an endoscope having a configuration capable of easily moving the moving lens 8 to a desired position of an observer with a simple structure without increasing the diameter of the distal end portion 109 of the insertion portion 101. 116 can be provided.

Hereinafter, modifications will be described.
In the present embodiment, it has been shown that the moving lens frame 180 and the moving lens 8 can be moved within the first moving range L1 corresponding to 1 to 100 times by the moving member 29. Of course, the magnification corresponding to the rearmost position P2 in the range L1 is not limited to 100 times. In this case, by changing the urging strength of the springs 21A and 21B, the magnification corresponding to the position P2 can be changed within the range of the enlarged observation.

  Further, in the present embodiment, it has been shown that the movable lens frame 180 and the movable lens 8 can be moved within the second movement range L2 corresponding to 100 times to 500 times by the moving member 30. Of course, the magnification corresponding to the rearmost position P3 in the movement range L2 is not limited to 500 times. In this case, the magnification corresponding to the position P2 can be changed within the ECS observation range by changing the urging strength of the springs 21A and 21B.

  Further, in the present embodiment, the spring 21A and the spring 21B regulate the movement of the moving lens frame 180 and the moving lens 8 outside the first movement range L1, and the moving lens frame 180 and the moving lens 8 are It is shown that the movement outside the second movement range L2 is restricted.

  Not limited to this, the shape memory alloy 22A is used in which the moving lens frame 180 can move only in the first movement range L1 with contraction, and the shape memory alloy 22B has the second moving lens frame 180 with the contraction. If the movable range L2 is used, the same effect as in the present embodiment can be obtained. In this case, the shape memory alloys 22A and 22B constitute the regulating member of the present embodiment.

  Furthermore, the biasing strength differs between the spring 21A and the spring 21B. Specifically, by using a spring 21A having a lower biasing strength than the spring 21B, the moving lens frame 180 and the moving lens 8 are used. May be restricted from moving outside the first movement range L1, and the movement of the moving lens frame 180 and the movement lens 8 outside the second movement range L2 may be restricted.

  Hereinafter, another modification will be described with reference to FIG. FIG. 7 is a partial cross-sectional view of the imaging unit showing that the moving lens frame in FIG. 2 is moved by a wire, and the moving amount by which the moving lens frame can be moved differs depending on the moving member.

  In the present embodiment, the moving lens frame 180 is moved by using the shape memory alloys 22A and 22B whose tips are fixed by the fixing members 20 at the tips of the protrusions 180t of the moving lens frame 180, respectively. Indicated.

  Not limited to this, as shown in FIG. 7, the wires 221 </ b> A and 221 </ b> B whose tips are fixed by the fixing members 220 may be used at the tips of the projecting portions 180 t of the moving lens frame 180.

  In this configuration, the other ends of the wires 221A and 221B are respectively connected to two cams that are rotated by the operation of the zoom lever 106 provided in the operation unit 104. Each of the wires 221A and 221B is pulled and relaxed, and the moving lens frame 180 moves in the first movement range L1 by the wire 221A as described above, and in the second movement range L2 by the wire 221B. To move.

  Therefore, in this case, the wire 221A constitutes the moving member 29 in the present embodiment, and the wire 221B constitutes the moving member 30 in the present embodiment. In addition, traction by the wire 221A constitutes a first action in a plurality of different actions, and traction by the wire 221B constitutes a second action in a plurality of different actions.

  Furthermore, the pulling of the wires 221A and 221B is not limited to the rotation of the cam, and may be performed using the above-described contraction of the shape memory alloy.

  In addition, as shown in FIG. 7, the moving lens frame 180 can be moved by the wire 221A in the first moving range L1 with respect to the moving amount in the second moving range L2 in which the moving lens frame 180 can be moved by the wire 221B. Even if the amount of movement is different, the same effect as in the present embodiment can be obtained.

  Specifically, the first moving range L1 and the second moving range L2 can be obtained by making the urging forces of the springs 21A and 21B different, as well as making the damping rates of the cams pulling the wires 221A and 221B different. The amount of movement by which the movable lens frame 180 can be moved may be different. This is the same even when the moving lens frame 180 is moved by the shape memory alloys 22A and 22B.

  Hereinafter, another modification will be described with reference to FIG. FIG. 8 is a chart showing a modification in which the moving amount of the moving lens frame in FIG. 2 per unit time varies depending on the moving member.

  As shown in FIG. 8, the moving distance x of the moving lens frame 180 per unit time in the first moving range L1 is different from the moving distance x of the moving lens frame 180 per unit time in the second moving range L2. It does not matter.

  Specifically, the moving distance x of the moving lens frame 180 per unit time in the first moving range L1 is set longer than the moving distance x of the moving lens frame 180 per unit time in the second moving range L2. It does not matter.

  That is, the movement of the moving lens frame 180 within the range where the observation magnification which is the first movement range L1 is 1 to 100 times is within the range where the observation magnification which is the second movement range L2 is 100 to 500 times. The moving lens frame 180 may be moved faster than the moving lens frame 180.

  This is because the change in the observation magnification of the objective lens group 100 within the first movement range L1 is variable at a relatively low magnification. Since the change in the observation magnification of the objective lens group 100 within the second movement range L2 is variable at a high magnification, it is difficult to adjust to a desired magnification if it is quickly varied. Therefore, it is better to move slowly.

  Specifically, the damping rate of each cam that pulls the wires 221A and 221B is made different so that the speed per unit time that pulls the wire 221B is slower than the speed per unit time that pulls the wire 221A. The rotation radius of each pulley that pulls the wires 221A and 221B may be varied.

  Hereinafter, another modification will be described with reference to FIG. FIG. 9 is a partial cross-sectional view of an imaging unit showing a modification in which two moving lens frames in FIG. 2 are provided and each moving lens frame is moved by a different moving member.

  In the present embodiment, one moving lens frame 180 holding one moving lens 8 is moved by two moving members 29 and 30 so that the observation magnification of the objective lens group 100 is 1 to 500 times. However, if the observation magnification is changed from 1 to 500 times by moving one moving lens 8 in a state where the distance between the observation site and the objective lens 1 is not changed, the higher the magnification, the more the observation is performed. Since the distance to the part changes, there is a problem that the observable range becomes small.

  Therefore, in this embodiment, in ECS observation, this problem has been solved by bringing the objective lens 1 closer to the observation site. However, the objective lens 1 is brought closer to the observation site every time ECS observation is performed. It is very cumbersome to do.

  In view of such circumstances, as shown in FIG. 9, the endoscope 116 includes a moving lens that changes the observation magnification of the objective lens group 100 in the imaging unit 300 as a first moving lens 8A and a second moving lens. The first moving lens frame 180A, which is composed of the moving lens 8B and holds the first moving lens 8A, is moved by the moving member 29, and the second movement located behind the first moving lens 8A. A configuration in which the second moving lens frame 180B holding the lens 8B is moved by the moving member 30 may be provided.

  Specifically, the moving member 29 is configured to move the first moving lens frame 180A and the first moving lens 8A within the first movement range L1 in the first operation as in the present embodiment. The moving member 30 is configured to move the second moving lens frame 180B and the second moving lens 8B in the second movement range L2 in the second operation similarly to the present embodiment. It has.

  That is, the first moving lens frame 180A and the first moving lens 8A perform zooming of 1 to 100 times, and the second moving lens frame 180B and the second moving lens 8B are 100 times to 500 times. Perform zooming.

  According to such a configuration, when performing the ECS observation, if the second moving lens frame 180B and the second moving lens 8B are moved by the moving member 30 within the second moving range L2, the objective lens 1 need not be close to the observation site.

  In addition, since the second moving lens 8B is located behind the first moving lens 8A, the length of the spring 21B that biases the second moving lens frame 180B is set to the first moving lens. Since the length of the spring 21A for biasing the frame 180A is shorter than the length of the spring 21A, as shown in FIG. 8 described above, the amount of movement of the second moving lens frame 180B per unit time is the first movement. The amount of movement of the lens frame 180A can be made smaller.

  That is, when the observation magnification is varied from 1 to 100 times with magnification observation, the first moving lens frame 180A can be quickly moved, and the observation magnification is 100 to 500 times with ECS observation. When changing to, the second moving lens frame 180B can be moved slowly.

  Here, the configuration shown in FIG. 9 is a configuration in which the moving lens frame is moved by one moving member with respect to one moving lens frame as in the prior art. Thus, there is a possibility that the moving lens frame 180 may be defective in sliding movement, or may be optically defective due to the inclination of the moving lens. However, each of the moving lens frames 180A and 180B has the protrusions 180t1 and 180t2. However, as described above, since the sliding movement is performed by fitting into the slit 27s of the second fixed lens frame 27, the shift can be minimized.

  The configuration shown in FIG. 9 has a configuration in which the first moving lens frame 180A is moved by the wire 221A and the second moving lens frame 180B is moved by the wire 221B. Of course, the shape memory alloys 22A and 22B may be used for movement as shown in FIG.

  In addition, another modification is shown using FIG. FIG. 10 is a partial cross-sectional view of an imaging unit showing a modification in which the two moving lenses in FIG. 9 are moved in conjunction with each other.

  As shown in FIG. 9, the first moving lens frame 180A that holds the first moving lens 8A when the moving lens is composed of two lenses as the first moving lens 8A and the second moving lens 8B. A wire 221A constituting the moving member 29 for moving the second moving lens 29 and a wire 221B constituting the moving member 30 for moving the second moving lens frame 180B holding the second moving lens 8B are provided in the operation unit 104. For example, by connecting to one pulley 250, the first moving lens 8A and the second moving lens 8B may be moved in conjunction with each other.

  In this case, on the other hand, when the pulley 250 is rotated in one direction by the zoom lever 106, the wire 221A performs the first operation of pulling the first moving lens frame 180A, whereby the first moving lens frame 180A. Is moved rearward, which is the first direction in the optical axis direction K, and the wire 221B performs a second operation of relaxing the pulling of the second moving lens frame 180B, whereby the second moving lens is moved by the spring 21B. The frame 180B moves in front of the optical axis direction K, which is the second direction in the optical axis direction K (hereinafter simply referred to as “front”).

  That is, when the first operation and the second operation are linked, the first moving lens frame 180A and the second moving lens frame 180B move in the optical axis direction K in conjunction with each other.

  On the other hand, when the pulley 250 is rotated in the other direction opposite to the one direction by the zoom lever 106, the wire 221B performs the second operation of pulling the second moving lens frame 180B, thereby The moving lens frame 180B is moved rearward in the first direction, and the wire 221A performs a first operation of relaxing the pulling of the first moving lens frame 180A, so that the first moving lens frame is moved by the spring 21A. 180A moves forward in the second direction.

  That is, when the first operation and the second operation are linked, the first moving lens frame 180A and the second moving lens frame 180B move in the optical axis direction K in conjunction with each other.

  Such a configuration also eliminates the need for the objective lens 1 to be close to the observation site when performing ECS observation.

  Note that the configuration shown in FIG. 10 also has a configuration in which the first moving lens frame 180A and the second moving lens frame 180B are moved in conjunction with the wire 221A and the wire 221B. Needless to say, the shape memory alloys 22A and 22B may be used in conjunction with each other as in the embodiment.

(Second Embodiment)
FIG. 11 is a partial cross-sectional view of the imaging unit in the endoscope showing the second embodiment.
The configuration of the endoscope according to the second embodiment is such that the moving lens frame that holds the moving lens is pulled and loosened as compared with the endoscope according to the first embodiment shown in FIGS. In addition, the point of movement is different depending on the movable member that can be rotated. Therefore, only this difference will be described, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted.

  As shown in FIG. 11, the moving lens frame 180 is formed with a protruding portion 180 t that protrudes from the moving lens frame 180 in the radial direction into the space 190 and slides into the slit 27 s of the second fixed lens frame 27. Has been.

  In the present embodiment, the movable lens frame 180 has a protrusion 180t formed only in the lower part of FIG. 11, and the second fixed lens frame 27 has a slit only in the lower part of FIG. 27s is not formed.

  Further, a through hole 180h that penetrates in the optical axis direction K is formed in the projecting portion 180t, and a screw groove 180n that constitutes a screw portion is formed in the inner periphery of the through hole 180h.

  The screw groove 180n is screwed with a screwing member 32 constituting a moving member 230 in which a screw groove is formed on the outer periphery that is rotatable around the optical axis direction K as a rotation center. A stopper 32s is formed at the tip. The rear end of the screwing member 32 is fixed to a wire fixing portion 33 to which the tip of the wire 221 constituting the moving member 230 is fixed.

Next, the operation of the present embodiment having such a configuration will be described.
First, when the movable lens frame 180 is moved within the first movement range L1 in order to perform magnified observation, the wire 221 is moved by pulling and loosening as the first operation in the optical axis direction K. The lens frame 180 is movable via the screwing member 32 so that the observation magnification of the objective lens group 100 is 1 to 100 times within the first movement range L1.

  When pulling, the wire fixing portion 33 comes into contact with the front end surface 27fs of the outward flange portion 27f of the second fixed lens frame 27, so that the moving lens frame 180 moves in the first movement along with the first operation. There is no possibility that the rear end position P2 of the range L1 moves backward.

  Next, when the movable lens frame 180 is moved within the second movement range L2 in order to perform ECS observation, a second operation for imparting a rotation operation to the wire 221 about the optical axis direction K as a rotation center. As a result, the moving lens frame 180 is movable so that the observation magnification of the objective lens group 100 becomes 100 to 500 times within the second moving range L2 by screwing of the screw groove 180n and the screwing member 32. It becomes.

  As described above, in the present embodiment, when the moving lens frame 180 is moved within the first movement range L1 for magnification observation, the first operation of pulling and relaxing the wire 221 is performed, and ECS observation is performed. Therefore, it has been shown that when the movable lens frame 180 is moved within the second movement range L2, the second operation of rotating the wire 221 is performed.

  According to this, the change of the observation magnification of the objective lens group 100 within the first movement range L1 can be quickly changed by pulling and loosening with the wire 221 and the objective lens group 100 within the second movement range L2. The observation magnification can be changed slowly using the screwing of the screw groove 180n and the screwing member 32.

  Therefore, the variable from 1 to 100 times can be quickly performed, and the variable from 100 to 500 times in the ECS observation in which it is difficult to adjust the observation magnification can be slowly performed. The moving lens frame 180 can be easily and accurately moved to the position.

  As described above, also in the present embodiment, when performing ECS observation, the moving lens 8 can be easily and accurately positioned at a desired position of the observer with a simple structure without increasing the diameter of the distal end portion 109 of the insertion portion 101. An endoscope having a configuration that can be moved to the position can be provided. Other effects are the same as those of the first embodiment described above.

  Hereinafter, modifications will be described. In the present embodiment, when the movable lens frame 180 is moved within the first movement range L1, the first operation of pulling and loosening the wire 221 is performed, and the movable lens frame 180 is moved to the second position for ECS observation. It has been shown that the movement within the movement range L2 is performed by the second operation of rotating the wire 221.

  Not limited to this, when the movable lens frame 180 is moved within the first movement range L1, the first operation of rotating the wire 221 opposite to the present embodiment is performed for ECS observation. When the movable lens frame 180 is moved within the second movement range L2, it may be performed by a second operation of pulling and loosening the wire 221 that is the reverse of the present embodiment.

  According to this, when performing ECS observation, the moving lens frame 180 can be quickly moved only by pulling and loosening the wire 221 from 100 times to 500 times or from 500 times to 100 times.

  In the present embodiment, the observation magnification of the objective lens group 100 within the second movement range L2 is changed by screwing the screw groove 180n and the screwing member 32. However, the present invention is not limited to this. Instead of the screwing member 32, a cam member that is rotatable about the optical axis direction K with a cam groove formed on the outer periphery is provided, and the protruding portion 180t of the moving lens frame 180 is provided in the rotating cam groove. Even if the second operation is performed by fitting them, the same effect as in the present embodiment can be obtained.

  Furthermore, the wire 221 used when the movable lens frame 180 is moved within the first movement range L1 may be a cylindrical member.

(Third embodiment)
FIG. 12 is a diagram showing a partial cross-sectional view of the imaging unit in the endoscope showing the third embodiment, together with the traction and relaxation devices for the wire and the cylindrical member.

  The configuration of the endoscope according to the third embodiment can pull and loosen the moving lens frame that holds the moving lens as compared with the endoscope according to the second embodiment shown in FIG. The difference is that it is moved by one moving member. Therefore, only this difference will be described, the same reference numerals are given to the same components as those in the second embodiment, and the description thereof will be omitted.

  As shown in FIG. 12, the moving lens frame 180 is formed with a protruding portion 180 t that protrudes from the moving lens frame 180 in the radial direction into the space 190 and slides into the slit 27 s of the second fixed lens frame 27. Has been.

  Also in the present embodiment, as in the second embodiment, the movable lens frame 180 has a protruding portion 180t formed only in the lower part of FIG. 12, and the second fixed lens frame 27 is also illustrated in FIG. The slit 27 s is formed only in the lower part of 12.

  The projecting portion 180t is formed with a through-hole 180h that penetrates in the optical axis direction K, and the through-hole 180h extends in the insertion portion 101 and the operation portion 104 along the optical axis direction K. The wire 221 constituting the moving member 330 of the form is inserted.

  The distal end of the wire 221 is fixed to the distal end surface of the protruding portion 180 t by a fixing member 220. A stopper 221 s is formed at the rear end of the wire 221. Furthermore, the tip of the wire 221w connected to the pulley 250A, which is a first traction / relaxation device that is rotatable by the zoom lever 106A provided in the operation unit 104, is fixed to the rear end of the stopper 221s. Yes.

  Further, the present embodiment extends along the optical axis direction K into the insertion portion 101 and the operation portion 104 on the outer periphery of a portion located between the protruding portion 180t and the outward flange portion 27f in the space 190 of the wire 221. A cylindrical member 135 constituting the moving member 330 is covered with the wire 221 in a loosely fitted state. That is, the wire 221 moves within the cylindrical member 135 along the optical axis direction K itself.

  An outward flange 135 s is formed at the front end of the cylindrical member 135, and a second end whose rear end is rotatable by a zoom lever 106 </ b> B provided in the operation unit 104 at the rear end of the cylindrical member 135. The tip of the wire 135w connected to the pulley 250B, which is a traction / relaxation device, is fixed. The tubular member 135 is in contact with the through hole 27h formed in the outward flange portion 27f with a predetermined frictional force.

Next, the operation of the present embodiment having such a configuration will be described.
First, when the movable lens frame 180 is moved within the first movement range L1 in order to perform magnified observation, the zoom lever 106A is operated to rotate the pulley 250A, so that the wire 221w and the wire 221 are moved. By performing traction and relaxation that is the first operation in the optical axis direction K, the moving lens frame 180 moves so that the observation magnification of the objective lens group 100 becomes 1 to 100 times within the first movement range L1. Be free.

  In addition, when the moving lens frame 180 comes into contact with the outward flange 135s at the tip of the cylindrical member 135 during towing, the moving lens frame 180 is in the first moving range L1 as described above. It does not move backward from the end position P2.

  Further, during the relaxation, the stopper 221s comes into contact with the rear end of the cylindrical member 135, so that the moving lens frame 180 moves forward from the position P1 of the first movement range L1 along with the first operation. There is no end.

  Next, in order to perform ECS observation, when moving the movable lens frame 180 within the second movement range L2, the zoom lever 106B is operated to rotate the pulley 250B, whereby the wire 135w and the cylindrical member 135 are moved. On the other hand, by performing pulling / relaxation that is the second operation in the optical axis direction K, the observation lens group 100 has an observation magnification of 100 to 500 times in the second movement range L2. It becomes so movable.

  When pulling, the outward flange 135s abuts on the distal end surface 27fs of the outward flange portion 27f of the second fixed lens frame 27, so that the movable lens frame 180 moves in the second movement range along with the second operation. It does not move backward from the above-mentioned rearmost position P3 of L2.

  As described above, in the present embodiment, when the moving lens frame 180 is moved within the first movement range L1 for magnification observation, the first operation of pulling and relaxing the wire 221 is performed, and ECS observation is performed. Therefore, it has been shown that the moving lens frame 180 is moved in the second movement range L2 by the second operation of pulling and relaxing the cylindrical member 135.

  According to this, the observation magnification of the objective lens group 100 within the first movement range L1 can be quickly changed by pulling and loosening with the wire 221, and the objective lens group within the second movement range L2. The observation magnification of 100 can be changed slowly by using friction between the cylindrical member 135 and the through-hole 27h formed in the outward flange portion 27f.

  Therefore, the variable from 1 to 100 times can be quickly performed, and the adjustment of the observation magnification is difficult. The variable from 100 to 500 times in the ECS observation can be slowly performed. The movable lens frame 180 can be easily and accurately moved to such a position.

  As described above, also in the present embodiment, when ECS observation is performed, the moving lens 8 can be easily and accurately positioned at a desired position of the observer with a simple structure without increasing the diameter of the distal end portion 109 of the insertion portion 101. An endoscope having a configuration that can be moved to the position can be provided. Other effects are the same as those of the second embodiment described above.

(Fourth embodiment)
FIG. 13 is a cross-sectional view schematically illustrating a configuration of an imaging unit provided in the distal end portion of the insertion portion of the endoscope according to the fourth embodiment.

  Compared with the endoscope of the first embodiment shown in FIGS. 1 to 6 described above, the configuration of the endoscope of the fourth embodiment is such that the moving lens frame that holds the moving lens has an optical axis. The movable lens frame is housed in a housing member that is movable in the direction, and the movable lens frame is movable in the optical axis direction within the housing member. Therefore, only this difference will be described, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted.

  As shown in FIG. 13, the movable lens frame 180 protrudes into the space 190 in the lower part of FIG. 13 in the radial direction from the movable lens frame 180 and slide-fits into the slit 27 s of the second fixed lens frame 27. A protruding portion 180t is formed.

  Also in the present embodiment, as in the second embodiment, the movable lens frame 180 is formed with a protruding portion 180t only in the lower part of FIG. 13, and the second fixed lens frame 27 is also illustrated in FIG. The slit 27 s is formed only in the lower part of 13.

  Further, in the lower space 190 in FIG. 13, on the actuator protection frame 19, in the optical axis direction K, the rear end 18 k that is a regulating member of the ring-shaped frame 18 and the outward flange of the second fixed lens frame 27. An accommodation member 36 having a concave cross-sectional shape that is movable in the optical axis direction K between the front end surface 27fs that is a regulating member of the portion 27f is provided. Further, a through hole 36 h is formed at the rear end portion of the housing member 36 in the optical axis direction K.

  Further, the wire 221 constituting the moving member 430 of the present embodiment extended into the insertion portion 101 and the operation portion 104 is inserted into the through hole 27h. The rear end of the wire 221 is connected to a pulley that is operated by, for example, the zoom lever 106 in the operation unit 104, and the front end is connected to the rear end side of the housing member 36.

  Therefore, the accommodating member 36 is movable between the rear end 18k and the front end surface 27fs in accordance with the pulling / relaxation which is the first operation of the wire 221.

  Further, the protrusion 180 t of the moving lens frame 180 on the housing member 36 in the optical axis direction K is a tip 36 s 2 that is a regulating member in the housing member 36 of the moving lens frame 180 and a regulating member in the housing member 36. It is accommodated so as to be movable in the optical axis direction K between the rear end 36k2. Further, a compression spring 421 is provided between the protruding portion 180t and the rear end 36k2.

  The shape memory alloy 138 constituting the moving member 430 extending along the optical axis direction K is inserted into the through holes 180h and 36h, and the tip of the shape memory alloy 138 is connected to the tip surface of the protrusion 180t. It is fixed by a fixing member 39.

  Further, on the rear end side of each shape memory alloy 138, specifically, in the vicinity of the rear end 36 k 1 of the housing member 36, the shape memory alloy 138 is operated with the operation of the zoom lever 106 of the operation unit 104 by the press contact terminal 422. The power supply line 40 for supplying current to the power supply side 138p is electrically connected, and the GND line 41 for supplying current to the GND side 138m of the shape memory alloy 138 is electrically connected. The diameter of the press contact terminal 422 is formed larger than the diameter of the through hole 36h. With such a configuration, the shape memory alloy 138 is arranged in a tensioned state without any slack by the compression spring 421 and the press contact terminal 422 in the housing member 36.

  The power supply line 40 and the GND line 41 are connected to the video processor 123 through the insertion unit 101, the operation unit 104, the universal cord 117, the connector 118, and the connection cable 122, and control (not shown) in the video processor 123 is performed. The apparatus controls the amount of current supplied to the power supply side 138p and the GND side 138m of the shape memory alloy 138 by detecting the resistance value accompanying the heat generation of the shape memory alloy 138.

  The shape memory alloy 138 contracts in the optical axis direction K while generating heat by supplying a current. That is, when a current is supplied to the shape memory alloy 138, the movable lens frame 180 moves in the optical axis direction within the housing member 36 in accordance with the expansion or contraction that is the first operation or the second operation of the shape memory alloy 138. As shown in FIG. 13, the rear end of the projecting portion 180 t is located on the rear end side of the housing member 36 from the position where the front end of the projecting portion 180 t is in contact with the front end 36 s 2 in the housing member 36. It moves to the position where it touches.

Next, the operation of the present embodiment configured as described above will be described.
First, when performing normal observation, the housing member 36 has a front end 36s1 of the housing member 36 that contacts the rear end 18k of the ring-shaped frame 18 and a front end of the protruding portion 180t that contacts the front end 36s2 in the housing member 36. It touches. That is, in FIG. 13, the moving lens frame 180 and the moving lens 8 are located on the most distal side.

  Next, first, when moving the movable lens frame 180 within the first movement range L1 for performing magnified observation, the zoom lever 106 is operated to perform the first operation in the optical axis direction K with respect to the wire 221. From the position where the front end 36s1 of the housing member 36 contacts the rear end of the ring-shaped frame 18 to the position where the rear end 36k1 of the storage member 36 contacts the front end surface 27fs of the outward flange portion 27f. It becomes movable. That is, the movable lens frame 180 accommodated in the accommodating member 36 is movable within the first movement range L1 so that the observation magnification of the objective lens group 100 is 1 to 100 times.

  In the enlarged observation, the shape memory alloy 138 is energized at the position where the front end 36s1 of the housing member 36 contacts the rear end 18k of the ring-shaped frame 18, and the front end of the projecting portion 180t is the front end 36s2 in the housing member 36. It may be performed using the fact that the protruding portion 180t is movable from a position where it comes into contact with the rear end 36k2 in the housing member 36 to a position where it comes into contact with the rear end 36k2. In this case, the expansion and contraction of the shape memory alloy 138 constitutes the first operation, and the movement range of the projecting portion 180t in the housing member 36 constitutes the first movement range L1.

  Next, when the movable lens frame 180 is moved within the second movement range L2 for ECS observation, the shape of the housing member 36 with the rear end 36k1 in contact with the front end surface 27fs of the outward flange portion 27f is determined. A current is supplied to the power supply side 138p and the GND side 138m of the memory alloy 138 through the power supply line 40 and the GND line 41 to expand and contract the shape memory alloy 138 which is the second operation.

  As a result, the protrusion 180t moves the compression spring 421 from the position where the tip of the protrusion 180t contacts the tip 36s2 in the storage member 36 to the position where it contacts the rear end 36k2 in the storage member 36 in the storage member 36. It becomes movable through. That is, the movable lens frame 180 is movable within the second movement range L2 so that the observation magnification of the objective lens group 100 is 100 to 500 times.

  As described above, in the present embodiment, when the movable lens frame 180 is moved within the first movement range L1 for magnification observation, the housing member 36 that houses the protruding portion 180t of the movable lens frame 180 is When the moving lens frame 180 is moved within the second moving range L2 for ECS observation by performing the first operation of pulling / relaxing with the wire 221 or expanding / shrinking the shape memory alloy with respect to the protrusion 180t. Shows that the second operation of expanding and contracting the shape memory alloy with respect to the protrusion 180t is performed.

  Even with such a configuration, the same effects as those of the first embodiment described above can be obtained, and the movement position of the housing member 36 can be controlled by the rear end 18k of the ring-shaped frame 18 and the front end surface of the outward flange portion 27f. Since the movement position of the projecting portion 180t is regulated by contact with the front end 36s2 and the rear end 36k2 in the housing member 36, observation can be performed in a more stable state.

  Hereinafter, a modification will be described with reference to FIG. FIG. 14 is a partial cross-sectional view illustrating a modification of the moving member with respect to the housing member and the protruding portion of the moving lens frame in FIG. 13.

  In the present embodiment, the housing member 36 is movable in the optical axis direction K by the wire 221, and the protrusion 180 t is movable in the optical axis direction K by the shape memory alloy 138.

  Not only this but as shown in FIG. 14, the protrusion part 180t may be movable to the optical axis direction K with the wire 221, and the accommodating member 36 was shown in 3rd Embodiment mentioned above. Such a cylindrical member 135 may be configured to be movable in the optical axis direction K. In other words, the projecting portion 180t and the moving member of the housing member 36 may be anything. For example, a SUS pipe, a blade, or the like may be used.

  Furthermore, in the first to fourth embodiments described above, a medical endoscope has been described as an example. However, the present invention is not limited thereto, and even when applied to an industrial endoscope, The same effect as this embodiment can be obtained.

(Fifth embodiment)
18 is a cross-sectional view showing an outline of the configuration of the imaging unit provided in the distal end portion of the insertion portion of the endoscope showing the present embodiment, and FIG. 19 is a cross-sectional view taken along line XIX-XIX in FIG. 20 is an enlarged perspective view showing the ring-shaped frame of FIG.

  21 is a partial sectional view showing the position of the moving lens in FIG. 18 in normal observation (1 ×), and FIG. 22 is the moving lens in FIG. 18 between normal observation and magnified observation (1 to 100 ×). FIG. 23 is a partial cross-sectional view showing the position of the moving lens in FIG. 18 during magnified observation (100 ×).

  Further, FIG. 24 is a partial cross-sectional view showing the position of the moving lens of FIG. 18 between magnification observation and ECS observation (100 to 500 times), and FIG. 25 is the moving lens of FIG. 18 in ECS observation (500 times). It is a fragmentary sectional view which shows the position.

  The configuration of the endoscope according to the fifth embodiment includes three moving lens frames that hold the moving lens as compared with the endoscope according to the first embodiment shown in FIGS. The point which moves with the above moving member differs. Therefore, only this difference will be described, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted.

  Also in this embodiment, as shown in FIGS. 4 and 5, slits 27 s along the optical axis direction K are formed above and below the second fixed lens frame 27 in FIG. 18. The two protruding portions 180t shown in FIG. 18 protruding in the radial direction of the moving lens 8 in the third moving lens frame 180C are slid into the slit 27s in the optical axis direction K. Note that the through hole 180h is not formed in the two projecting portions 180t of the present embodiment.

  A hole penetrating in the radial direction of the lens 8 is formed on the rear end side of the actuator protection frame 19, and a regulating member 301b is bonded and fixed to the hole. The restricting member 301b restricts the third moving lens frame 180C from moving from the 500 times position corresponding to ECS observation to the rear end side in the optical axis direction K.

  Further, a hole penetrating in the radial direction of the lens 8 is formed on the distal end side of the regulating member 301b of the actuator protection frame 19, and the regulating member 301a is bonded and fixed to the hole.

  Further, in the present embodiment, as shown in FIGS. 18 and 20, an end face 18c whose rear end protrudes is provided on the lower half side of the ring-shaped frame 18a. The end face 18c restricts the third moving lens frame 180C from moving from the position corresponding to normal observation to the tip side.

  As shown in FIGS. 18 and 20, a stepped portion 18b resulting from the end surface 18c is formed on the rear end surface on the upper end side of the ring-shaped frame 18a, and the stepped portion 18b and the third moving lens frame 180C are formed. A spring 21C, which is a moving member and an elastic member, is disposed between the upper protruding portion 180t in FIG. The spring 21C biases the third moving lens frame 180C to the rear end side.

  Further, in FIG. 18, the rear end surfaces of the two protruding portions 180 t form contact surfaces with moving lens frame moving members 300 </ b> A and 300 </ b> B that are moving members described later. A force biased toward the front end side by the moving lens frame moving members 300A and 300B and a force biased toward the rear end side by the spring 21C are applied to each contact surface in a balanced manner. Thus, the third moving lens frame 180C is configured to be movable in the optical axis direction K.

  As shown in FIGS. 18 and 19, the moving lens frame moving member 300B is fitted between the outer peripheral portion of the second fixed lens frame 27 and the inner peripheral portion of the actuator protection frame 19, and FIG. It is provided on the lower end side in FIG. 19 and is movable with respect to the optical axis direction K.

  A step 27b is provided at the lower end of the rear end side of the second lens fixing frame 27 as shown in FIG. The step 27b restricts the movement of the moving lens frame moving member 300B to the rear end side. Note that the movement of the moving lens frame moving member 300B toward the distal end in the optical axis direction K is restricted by the end face 18c of the ring-shaped frame 18a described above.

  In addition, a spring 21 </ b> D that is a moving member and an elastic member is disposed between the moving lens frame moving member 300 </ b> B and the rear end portion of the second fixed lens frame 27. The spring 21D biases the moving lens frame moving member 300B toward the distal end side.

  Furthermore, the tip of a shape memory alloy 22B, which is a moving member extending along the optical axis direction K, is fixed to the moving lens frame moving member 300B. On the rear end side of the shape memory alloy 22B, the power line 24B for supplying current to the power source side of the shape memory alloy 22B is electrically connected in accordance with the operation of the zoom lever 106 (see FIG. 1) of the operation unit 104. In addition, a GND line 25B for supplying a current to the GND side of the shape memory alloy 22B is electrically connected. The configurations of the power supply line 24B and the GND line 25B are the same as those in the first embodiment described above.

  The shape memory alloy 22B contracts in the optical axis direction K while generating heat by supplying current. Accordingly, the lens moving frame moving member 300B moves from the position where the normal observation shown in FIG. 21 is performed to the position where the enlarged observation shown in FIG. 23 is performed against the bias of the spring 21D.

  Incidentally, as shown in FIGS. 21 to 23, when the lens moving frame moving member 300B is in contact with the third moving lens frame 180C, the spring 21C moves the third moving lens frame 180C as described above. The spring 21D is biased toward the rear end side, and is in a state of biasing the third moving lens frame 180C toward the front end side via the lens moving frame moving member 300B. That is, the spring 21C and the spring 21D bias the third moving lens frame 180C in the optical axis direction K in a state of being antagonistic to each other.

  Here, the spring 21 </ b> C is most contracted during the state shown in FIG. 21, that is, during normal observation, and is in a state where the urging force is the largest. The biasing force of the spring 21C at this time is Fcmax. Further, the spring 21 </ b> D is in the state where it is most expanded and has the smallest urging force during the normal observation shown in FIG. 21. Assuming that the biasing force of the spring 21D at this time is Fdmin, Fcmax and Fdmin satisfy the relationship of Fcmax <Fdmin. That is, the biasing force of the spring 21D is always larger than the biasing force of the spring 21C within the first movement range L1 of the third moving lens frame 180C shown in FIGS.

  As shown in FIGS. 18 and 19, the moving lens frame moving member 300A is fitted between the outer peripheral portion of the second fixed lens frame 27 and the inner peripheral portion of the actuator protection frame 19, and FIG. It is provided on the upper end side in FIG. 19 and is movable with respect to the optical axis direction K.

  As shown in FIG. 18, a step 27 a is provided at the upper end portion on the rear end side of the second lens fixing frame 27. The step 27a restricts the movement of the moving lens frame moving member 300A toward the rear end side. Note that the movement of the moving lens frame moving member 300A toward the front end side is restricted by the restriction member 301a described above.

  In addition, a spring 21 </ b> E that is a moving member and an elastic member is disposed between the moving lens frame moving member 300 </ b> A and the rear end portion of the second fixed lens frame 27. The spring 21E biases the moving lens frame moving member 300A toward the distal end side.

  Furthermore, the tip of the shape memory alloy 22A, which is a moving member extending along the optical axis direction K, is fixed to the moving lens frame moving member 300A. On the rear end side of the shape memory alloy 22A, a power line 24A for supplying current to the power source side of the shape memory alloy 22A is electrically connected in accordance with the operation of the zoom lever 106 (see FIG. 1) of the operation unit 104. In addition, a GND line 25A for supplying a current to the GND side of the shape memory alloy 22A is electrically connected. The configurations of the power supply line 24A and the GND line 25A are the same as those in the first embodiment described above.

  The shape memory alloy 22A contracts in the optical axis direction K while generating heat by supplying current. Accordingly, the lens moving frame moving member 300A moves from the position where the normal observation shown in FIG. 21 is performed to the position where the ECS observation shown in FIG. 25 is performed against the bias of the spring 21E.

  By the way, as shown in FIGS. 23 to 25, when the shape memory alloy 22B contracts and the lens moving frame moving member 300B and the third moving lens frame 180C are not in contact with each other, the spring 21C is as described above. The third moving lens frame 180C is biased to the rear end side, and the spring 21E is in a state of biasing the third moving lens frame 180C to the front end side via the lens moving frame moving member 300A. That is, the spring 21 </ b> C and the spring 21 </ b> E urge the third moving lens frame 180 </ b> C in the optical axis direction K in a state of being antagonistic to each other.

  Here, when the lens moving frame moving member 300A and the third moving lens frame 180C are in contact with each other during the magnification observation shown in FIG. 23, the spring 21C is limited to the middle shown in FIGS. Is most contracted, and the urging force of the spring 21 </ b> C is the largest in FIGS. 23 to 25. The biasing force of the spring 21C at this time is Fcmin.

  In addition, the spring 21E is in the state where it expands most and the urging force is the smallest during the enlarged observation shown in FIG. If the biasing force of the spring 21D at this time is Femin, Fcmin and Femin satisfy the relationship of Fcmin <Femin. That is, the urging force of the spring 21E is always greater than the urging force of the spring 21C within the second movement range L2 of the third moving lens frame 180C shown in FIGS.

  From the above, in the first movement range L1, the third movement lens frame 180C is configured to move by contraction of the shape memory alloy 22B which is the first operation, and in the second movement range L2, The third moving lens frame 180C has a second operation when the shape memory alloy 22B contracts and the lens moving frame moving member 300B is in contact with the step 27b of the second second fixed lens frame 27. It is configured to move by contraction of a certain shape memory alloy 22A.

  By the way, a potentiometer (not shown) is attached to the rotation shaft of the zoom lever 106 (see FIG. 1) so that the rotation angle of the zoom lever 106 can be detected. The rotation limit angle of the zoom lever 106 is, for example, 120 °, and the current conduction state to the shape memory alloys 22A and 22B differs depending on the output value of the potentiometer.

  Specifically, when the rotation angle of the zoom lever 106 is 0 ° to 40 °, the shape memory alloy 22A is not energized and the shape memory alloy 22A is not contracted. In addition, the shape memory alloy 22B is not energized, and the shape memory alloy 22B is not contracted. As a result, the third moving lens frame 180C is positioned at a position where normal observation (1 ×) is performed.

  Further, when the rotation angle of the zoom lever 106 is 40 ° to 80 °, the shape memory alloy 22A is not energized and the shape memory alloy 22A is not contracted, but the shape memory alloy 22B is energized and the shape memory alloy is energized. 22B is designed to be contracted. That is, the third moving lens frame 180C can be moved to a position where normal observation (1 ×) to enlarged observation (100 ×) is performed.

  Further, even when the rotation angle of the zoom lever 106 is between 80 ° and 120 °, the shape memory alloy 22B is also energized, and the shape memory alloy 22B is contracted. The shape memory alloy 22A is also energized, and the shape memory alloy 22A contracts. That is, the third moving lens frame 180C can be moved to a position for performing magnified observation (100 times) to ECS observation (500 times).

Next, the operation of the embodiment configured as described above will be described.
Usually, the operator first observes the inside of the body cavity by setting the rotation angle of the zoom lever 106 between 0 ° and 40 ° for normal observation. In this case, since the shape memory alloy 22A is not energized as described above, the shape memory alloy 22A is not contracted, and the shape memory alloy 22B is not energized, and the shape memory alloy 22B is not contracted.

  In this case, as described above, since the biasing force of the spring 21D is stronger than the biasing force of the spring 21C (Fcmax <Fdmin), the third moving lens frame 180C is biased toward the distal end side by the spring 21D. As shown in FIG. 21, the lens moving frame moving member 300B is brought into contact with the end face 18c of the ring-shaped frame 18a. That is, the normal observation state with an observation magnification of 1 is obtained. When a site that is suspected of being a lesion is found by normal observation, the surgeon stores an image of the site in an image recording device (not shown) connected to the video processor 123 (see FIG. 1).

  Next, the zoom lever 106 is rotated, and the rotation angle is set between 40 ° and 80 °. In this case, since the shape memory alloy 22A is not energized as described above, the shape memory alloy 22A is not contracted, but the shape memory alloy 22B is energized, and thus the shape memory alloy 22B is contracted. 23, the shape memory alloy 22B is contracted until the lens moving frame moving member 300B comes into contact with the step 27b.

  As a result, the third moving lens frame 180C is moved at the position shown in FIGS. 22 and 23 by the biasing force of the spring 21C, and the position of the third moving lens frame 180C is regulated by the regulating member 301a. It moves until it abuts on the member 300A, and the observation magnification is in an enlarged observation state of 1 to 100 times. In this state, a minute tissue such as a capillary vessel is observed to proceed with diagnosis, and an image with a magnification of 1 to 100 is stored in the image recording apparatus. At this time, since the biasing force of the spring 21E is stronger than the biasing force of the spring 21C (Fcmin <Femin), the third moving lens frame 180C does not move to the rear end side from the position shown in FIG.

  Further, the zoom lever 106 is rotated, and the rotation angle is set between 80 ° and 120 °. In this case, as described above, the shape memory alloy 22A is energized, the shape memory alloy 22A contracts, and the shape memory alloy 22B is also energized, so that the shape memory alloy 22B also contracts. At the ECS observation position shown in FIG. 25, the shape memory alloy 22A is contracted until the lens moving frame moving member 300A comes into contact with the step 27a.

  As a result, the third moving lens frame 180C moves to the position shown in FIGS. 24 and 25, and enters an ECS observation state in which the observation magnification is 100 to 500 times. In the ECS observation shown in FIG. 25, the third moving lens frame 180C comes into contact with the regulating member 301b by the biasing force of the spring 21C. In this state, the diagnosis of the running of the capillaries and the like is observed to advance the diagnosis, and an image with an ECS observation magnification of 100 to 500 times is stored in the image recording apparatus.

  Thereafter, in order to perform normal observation again, the zoom lever 106 is set between 0 ° and 40 °, the third moving lens frame 180C is moved to the position shown in FIG. 21, and other places are normally observed. Look for suspected lesions.

  In addition, if there is a suspicious part, the observation magnification is similarly changed to normal observation (1 ×), magnified observation (100 ×), ECS observation (500 ×), diagnosis is performed, and normal observation ( (1 ×), magnified observation (100 ×), and images observed by ECS observation (500 ×) are stored.

  Thus, according to the present embodiment, the operator can switch the three types of observation magnifications (normal observation: 1 ×, magnified observation: 100 ×, ECS observation: 500 ×) with good reproducibility without fine adjustment. it can. That is, it is possible to provide an endoscope in which the magnification change operation is easier. In addition, images observed in normal observation, magnified observation, and ECS observation can always be stored at the same magnification, and thereafter it becomes easy to compare and examine the images.

  Further, switching of the three types of observation magnifications can be performed only by combining the two shape memory alloys 22A and 22B with binary control of on / off. That is, since the magnification of the observation magnification can be changed with a simple control circuit, the endoscope can be provided at a lower cost.

  In this embodiment, the lens moving frame moving members 300A and 300B are moved by the shape memory alloys 22A and 22B and the springs 21D and 21E. However, one or both of them may be a linear actuator such as a solenoid. Similar effects can be obtained. Other effects are the same as those of the first to fourth embodiments described above.

[Appendix]
As described in detail above, according to the embodiment of the present invention, the following configuration can be obtained. That is,
(1) Since at least one lens in the objective lens group for observing the subject constitutes a movable lens that is movable with respect to the optical axis direction of the objective lens group, the optical characteristics of the objective lens group can be varied. In the endoscope,
A moving lens frame for holding the moving lens;
A moving member that moves the moving lens frame by a plurality of different operations with respect to the optical axis direction;
Comprising
The moving member is
Moving the moving lens frame within a first movement range with respect to the optical axis direction by a first operation in the plurality of different operations;
An endoscope, wherein the moving lens frame is moved within a second movement range with respect to the optical axis direction by a second operation different from the first operation in the plurality of different operations.

  (2) The moving member adjusts the observation magnification for changing the optical characteristics of the objective lens group to a magnification lower than a set magnification by the first operation, and the set magnification by the second operation. The endoscope according to appendix 1, wherein the endoscope is adjusted to a higher magnification.

  (3) The moving lens frame is restricted from moving outside the first movement range in the optical axis direction along with the first operation, and the movement along with the second operation. The endoscope according to appendix 1 or 2, further comprising a regulating member that regulates movement of the lens frame outside the second movement range in the optical axis direction.

(4) An elastic member that urges the moving lens frame toward the front end side or the rear end side in the optical axis direction is provided.
The additional lens according to claim 3, further comprising a plurality of actuators that realize the first operation and the second operation by applying a force in the direction opposite to the urging force of the elastic member to the movable lens frame. Endoscope.

  (5) The endoscope according to appendix 4, wherein the actuator includes a shape memory alloy and an elastic member.

  (6) The endoscope according to appendix 4, wherein the actuator includes a solenoid.

(7) In an endoscope provided with an objective lens group for observing a subject in the distal end portion of the insertion portion,
A first lens facing the distal end surface of the distal end portion, constituting the objective lens group;
A second lens that constitutes the objective lens group and is located on the rear end side in the optical axis direction with respect to the first lens;
Comprising
A second spherical notch portion having the same shape as the first spherical missing portion of the rear end surface of the first lens in the optical axis rear end side at the distal end surface of the second lens in the optical axis direction distal end side. The endoscope is characterized in that the second sphere notch is joined to the first sphere notch.

  By the way, in the conventional endoscope, as shown in FIG. 2 described above, the objective lens 1 located at the most distal end side in the optical axis direction K in the objective lens group 100 in the distal end portion 109 of the insertion portion 101 is used. The objective lens 2 positioned on the rear end side in the optical axis direction K of the objective lens 1 has a space between the objective lens 1 and the spherical notch 1q formed on the rear end surface of the objective lens 1. The front end surface was fixed in a state of being in contact with the rear end surface of the objective lens 1, or the objective lens 2 was fixed at a position away from the objective lens 1 by a predetermined distance.

  However, in such a configuration, for example, when the insertion portion 101 is inserted into the body cavity in a state where the insertion portion 101 is cold, the distal end portion 109 enters the distal end portion 109 from the distal end side in the optical axis direction K. In some cases, moisture in the atmosphere may enter, and the spherical notch 1q of the objective lens 1 may become cloudy, making it difficult to perform endoscopic observation.

  Therefore, hereinafter, a configuration for preventing the cloudy part 1q of the objective lens 1 from being fogged due to the entry of moisture in the atmosphere will be described with reference to FIG.

  As shown in FIG. 13, the objective lens 1 that is the first lens constituting the objective lens group 100 is held and fixed on the distal end side in the optical axis direction K of the first fixed lens frame 26. Specifically, the objective lens 1 is fixed by fitting and bonding the outer peripheral surface 1 s of the objective lens 1 to the inner peripheral surface of the first fixed lens frame 26.

  Further, behind the objective lens 1, an objective lens 43, which is a second lens constituting the objective lens group 100, is held and fixed by the first fixed lens frame 26. Specifically, the second sphere notch 43q formed on the front end surface of the objective lens 43 formed in the same shape as the first sphere notch 1q formed on the rear end surface of the objective lens 1 is the first sphere. The objective lens 43 is fixed by fitting and bonding the outer peripheral surface 43s of the objective lens 43 to the inner peripheral surface of the first fixed lens frame 26 so as to be closely joined to the notch 1q.

  According to such a configuration, the second spherical notch 43q having the same shape as the first spherical notch is closely joined to the first spherical notch 1q. It is possible to reliably prevent the first spherical notch portion 1q from becoming cloudy with the entry of moisture in the atmosphere into the portion 109.

  The objective lens 1 has an outer peripheral surface 1s bonded to an inner peripheral surface of the first fixed lens frame 26, in addition to the second spherical notch portion 43q being closely joined to the first spherical notch portion 1q. The objective lens 43 is fitted and fixed to the first fixed lens frame 26, and the objective lens 43 is fitted and fixed to the first fixed lens frame 26 with the outer peripheral surface 43 s bonded to the inner peripheral surface of the first fixed lens frame 26. For this reason, the path of moisture in the atmosphere into the tip 109 becomes longer than before due to adhesion at each part. Therefore, it is possible to prevent moisture in the atmosphere from entering the tip portion 109 more.

(8) In an endoscope including an imaging unit in the distal end of the insertion portion in the optical axis direction,
The imaging unit includes an imaging element, a cover glass for adjusting a fixed position of the imaging element with respect to an element frame provided on the distal end side in the optical axis direction of the imaging element, and the electrical connection to the imaging element An electrical substrate that transmits and receives electrical signals to and from the image sensor;
The endoscope characterized in that an outer periphery of the imaging element, the cover glass, and the electric substrate is covered by one element frame.

  (9) The endoscope according to appendix 8, wherein a step part into which the cover glass is fitted is formed on an inner periphery of the element frame.

  (10) The appendix 8 or 9 is characterized in that the connection portion of the signal cable on the electric board protrudes more toward the rear end side in the optical axis direction than the rear end portion in the optical axis direction of the element frame. Endoscope.

  (11) The endoscope according to appendix 8 or 9, wherein the element frame further covers a connection portion of the signal cable in the electric board.

  (12) The element frame includes an inward flange portion projecting in an inner circumferential direction at a rear end in the optical axis direction, and the rear end in the optical axis direction of the electric board is in contact with the inward flange portion. The endoscope according to any one of appendices 8 to 11, wherein the endoscope is characterized in that

  FIG. 15 is a partial cross-sectional view showing an example in which an element frame to which a solid-state image sensor in the image-capturing unit is fixed is provided up to a length that covers the outer periphery of the connection portion of the signal cable of the substrate connected to the solid-state image sensor. FIG. 16 is a partial cross-sectional view showing an example in which an inward flange portion is provided at the rear end in the optical axis direction of the element frame of FIG. 15.

  Incidentally, in recent years, in order to reduce the diameter of the distal end portion 109 in the insertion portion 101 of the endoscope, a configuration in which a built-in object is provided in the distal end portion 109 with an increased filling rate is well known. However, when the filling rate of the built-in material in the distal end portion 109 increases, stress is generated in the distal end portion 109 along with the bending operation of the bending portion 102 formed on the rear end side of the distal end portion 109 of the insertion portion 101, In some cases, the adhesion of parts around the fixed imaging element in the imaging device of the imaging unit may be peeled off.

  Specifically, as shown in FIG. 2, conventionally, when fixing the solid-state imaging device 13 to the element frame 28, first, a cover glass 12 is attached to the imaging surface of the solid-state imaging device 13, and then the cover glass. The centering cover glass 11 is adhered to the front end surface of the glass 12 so that the center of the cover glass 12 coincides with the center of the centering cover glass 11. Thereafter, the centering cover glass 11 is fixed to the inward flange portion 28f of the element frame 28 so that the center of the imaging surface of the solid-state imaging device 13 and the optical axis center of the objective lens group 100 coincide from the rear in the optical axis direction K. To do.

  However, in this case, since the solid-state image pickup device 13 is fixed in the space in the protective frame 15 by the thermoplastic resin 149, when the stress is applied due to the bending operation of the bending portion 102, the solid-state imaging device 13 is cored. Stress tends to concentrate between the cover glass 11 and the solid-state image sensor 13, and peeling easily occurs between the centering cover glass 11 and the cover glass 12 or between the cover glass 12 and the solid-state image sensor 13. There was a problem such as.

Therefore, a structure for preventing peeling will be described below with reference to FIGS. 13, 15, and 16. FIG.
As shown in FIG. 13, the metal element frame 50 that holds the solid-state imaging device 13 is a signal of a substrate 49 that is constituted by a centering cover glass 11, a cover glass 12, a solid-state imaging device 13, a rigid substrate, or a laminated substrate. The cable 17 extends along the optical axis direction K so as to cover the outer periphery of the portion excluding the connection portion 49t.

  Further, a step portion 50 d with which the outer peripheral edge portion of the rear end surface of the centering cover glass 11 abuts is formed in the rear half portion in the optical axis direction K on the inner periphery of the element frame 50.

  Further, the outer periphery of the cover glass 12, the solid-state imaging device 13, and the substrate 49 is bonded and fixed to the inner periphery of the rear half of the element frame 50 with an adhesive 55.

  The distal end side of the heat shrinkable tube 52 is fixed to the outer periphery on the rear end side of the element frame 50. The rear end side of the heat shrinkable tube 52 is fixed to the front end side of the signal cable 17. The heat shrinkable tube 52 is filled with a thermoplastic resin 149.

  When fixing the solid-state imaging device 13 to the element frame 50 having such a configuration, first, the centering cover glass 11 to which the solid-state imaging device 13 is attached and the cover glass 12 is attached, From the front end side in the optical axis direction K, it is brought into contact with the step portion 50d of the element frame 50. In this state, the inner periphery of the element frame 50 and the outer periphery of the centering cover glass 11 are fitted and in close contact. Further, the optical axis centers of the solid-state imaging device 13 and the objective lens group 100 coincide with each other. Further, a diaphragm 46 is provided on the front end surface of the centering cover glass 11.

  Thereafter, the outer periphery of the cover glass 12, the solid-state imaging device 13, and the substrate 49 is bonded and fixed to the inner periphery of the rear half of the element frame 50 with an adhesive 55.

  According to such a configuration, even when the bending portion 102 performs a bending operation and stress is applied to the element frame 50, the outer periphery of the centering cover glass 11, the cover glass 12, the solid-state imaging device 13, and the substrate 49 is In addition to being covered with the element frame 50, the centering cover glass 11 is in contact with the step portion 50 d of the element frame 50, so that the bonding surface between the centering cover glass 11 and the cover glass 12 and the substrate 49 are covered. Since stress becomes difficult to concentrate, peeling between each member is prevented.

  In addition, since the outer periphery of the substrate 49 is bonded and fixed to the inner peripheral surface of the element frame 50 with the adhesive 55, even if stress such as curling is applied to the thermoplastic resin 149, the periphery of the solid-state imaging device 13 The influence of stress on the can be reduced.

  Furthermore, since the element frame 50 covers the outer periphery of the centering cover glass 11, the cover glass 12, the solid-state imaging device 13, and the substrate 49, it is not necessary to use the protective frame 15 as shown in FIG. The tip 109 can be reduced in size and diameter. Moreover, since the element frame 50 is comprised with the metal material, the heat dissipation from an imaging device improves.

  Further, as shown in FIG. 15, if the element frame 50 is formed so as to cover the connection portion 49 t of the signal cable 17 of the substrate 49 and further to cover the distal end side of the signal cable 17, the bending portion The influence of the stress accompanying the curvature of 102 can be avoided more reliably.

  Further, as shown in FIG. 16, an inward flange portion 56 is provided at the rear end of the element frame 50, and a rear end 49k of a substrate 49 made of a rigid substrate or a laminated substrate is brought into contact with the inward flange portion 56. In this state, the substrate 49 may be bonded and fixed to the inner periphery of the element frame 50 with an adhesive. According to such a configuration, it is possible to avoid the influence of stress on the substrate 49, and to more reliably prevent light from entering the imaging device from outside and noise interference. Stabilization of the displayed image can be realized.

(13) In an endoscope including an imaging unit in the distal end portion of the insertion portion,
The imaging unit is in a hard tip portion provided in the tip portion,
An objective lens group for observing the subject;
A prism provided behind the objective lens group in the optical axis direction;
An imaging element provided on an imaging surface, the imaging surface of which is focused by the objective lens group by the prism, the imaging surface being provided in parallel with the optical axis;
An electrical board that is electrically connected to the image sensor and transmits and receives electrical signals to and from the image sensor provided to be parallel to the optical axis;
An endoscope comprising:

  (14) The endoscope according to appendix 13, wherein the electric board is provided in a groove parallel to the optical axis in the hard tip portion.

  (15) The appendix 13 or 14 is characterized in that the prism is fixed to an annular frame fitted to an inner periphery of a rear end in the optical axis direction of the frame holding the objective lens group. Endoscope.

  (16) A signal cable is electrically connected to a substrate electrically connected to the imaging element, and the signal cable is fixed to an inner periphery of the hard tip portion via a fixing member. The endoscope according to any one of appendices 13 to 15, characterized in that the endoscope is provided.

  (17) The endoscope according to appendix 16, wherein a resin is filled in a space closed by the fixing member in the distal end hard portion.

  FIG. 17 is a partial cross-sectional view illustrating an example in which the imaging surface of the imaging device and the substrate connected to the imaging device are positioned in parallel with the optical axis in the distal end portion of the endoscope.

  Incidentally, in recent years, in order to reduce the diameter of the distal end portion 109 in the insertion portion 101 of the endoscope, a configuration in which a built-in object is provided in the distal end portion 109 with an increased filling rate is well known. However, when the filling rate of the built-in object in the distal end portion 109 is increased, the stress associated with the bending operation of the bending portion 102 formed on the rear end side of the distal end portion 109 of the insertion portion 101 is applied. In some cases, the adhesion of parts around the fixed imaging element in the imaging apparatus is peeled off.

  Specifically, as shown in FIG. 2, when fixing the solid-state imaging device 13 to the element frame 28, first, the cover glass 12 is attached to the imaging surface at the tip of the solid-state imaging device 13, and then the cover glass. The centering cover glass 11 is attached to the front end surface of the cover glass 12 so that the optical axis center of the cover glass 12 coincides with the optical axis center of the centering cover glass 11.

  Thereafter, the centering cover glass 11 is fixed to the inward flange portion 28f of the element frame 28 so that the center of the imaging surface of the solid-state imaging device 13 and the optical axis center of the objective lens group 100 coincide from the rear in the optical axis direction K. To do.

  However, in this case, since the solid-state image pickup device 13 is fixed in the space in the protective frame 15 by the thermoplastic resin 149, when the stress is applied due to the bending operation of the bending portion 102, the solid-state imaging device 13 is cored. Stress tends to concentrate between the cover glass 11 and the solid-state image sensor 13, and peeling between the centering cover glass 11 and the cover glass 12 and between the cover glass 12 and the solid-state image sensor 13 is likely to occur. There was a problem such as.

  Further, as shown in FIG. 2, since the solid-state imaging device 13 and the substrate 14 are provided behind the objective lens group 100, the solid-state imaging device 13 and the substrate 14 are associated with the bending operation of the bending portion 102. Etc., there is a problem that they are more likely to interfere with the built-in objects behind the hard tip portion in the tip portion 109.

  Furthermore, since the substrate 14 is provided in the vicinity of the solid-state imaging device 13, heat is applied to the solid-state imaging device 13 as the substrate 14 generates heat, and noise is generated in imaging by the solid-state imaging device 13. In some cases, the quality of the captured image may be degraded.

  As shown in FIG. 2, in an endoscope with a zoom function, in the objective lens group 100, a plurality of objective lenses are provided, and considering the movement range of the moving lens 8, the tip 109 is in the optical axis direction. There was also a problem that K would become longer.

Therefore, a configuration for preventing the above problem will be described below with reference to FIG.
As shown in FIG. 17, the tip portion 109 is composed of a tip hard portion 68 formed of, for example, a metal material. A tip cover 69 is covered on the tip surface of the tip hard portion 68.

  A through hole 68s along the optical axis direction K is formed substantially at the center of the distal end hard portion 68, and a first holding the objective lenses 1, 4, 5 is provided on the inner periphery of the distal end side in the through hole 68s. The fixed lens frame 26 is fixed.

  In addition, in the through hole 68s, a second fixed lens frame 227 that holds the moving lens frame 180 and the objective lenses 9 and 10 is disposed at the rear end portion of the first fixed lens frame 26 through the thermoplastic resin 149. It is fixed to the inner circumference.

  In FIG. 17, the movable lens frame 180 has a protruding portion 180t formed only in the lower part of FIG. 17, and the second fixed lens frame 27 has a slit 27s only in the lower part of FIG. Not formed.

  The configuration of the second fixed lens frame 227 is substantially the same as the configuration of the second fixed lens frame 27 described above, except that the outward flange portion 27f is not provided at the rear end, and thus the description thereof is omitted. .

  An annular frame 63 is fixed to the inner periphery of the rear end of the second fixed lens frame 227. Here, a space portion 68p having a diameter larger than that of the through hole 68s communicating with the through hole 68s is formed inside the distal end hard portion 68. In the space portion 68p, a prism 61 fixed to the annular portion 63 is provided. The prism 61 changes the direction of the light collected by the objective lens group 100, for example, upward in FIG.

  A cover glass 58 is attached to the upper surface of the prism 61, and a solid-state image sensor 66 is attached to the upper surface of the cover glass 58. Thereby, the imaging surface located on the bottom surface side in FIG. 17 of the solid-state imaging device 66 is positioned in parallel with the optical axis direction K.

  In addition, a groove 68m parallel to the optical axis direction K communicating with the space 68p is formed in the distal end hard portion 68 above the through hole 68s in FIG.

  A substrate 166 having a diameter larger than that of the two stacked solid-state image pickup elements 66 is attached to the upper surface of the solid-state image pickup element 66, and the rear surface of the substrate 65 extending in the groove 68m is attached to the upper surface of the substrate 166. The bottom of the end is attached.

  A plurality of electronic components 64 are mounted on the bottom surface of the substrate 65 located in the groove 68m. Therefore, the substrate 65 and the plurality of electronic components 64 are positioned parallel to the optical axis direction K, and parallel to the optical axis direction K by the groove 68m in the distal end hard portion 68 at the upper side of the objective lens group 100 in FIG. It is located via the extending part 68e located.

  In addition, a lead wire connecting portion 59 to which a lead wire extending from the signal cable 60 is connected is provided on the bottom surface of the substrate 166 excluding the solid-state imaging device 66. Furthermore, the signal cable 60 is fixed to the inner peripheral surface of the distal end hard portion 68 in the space portion 68p by a fixing member 67. Further, a wire 221 that moves the protruding portion 180t of the moving lens frame 180 in the optical axis direction K is extended from the space 68p to the rear end side between the fixing member 67 and the outer peripheral surface of the signal cable 60. Yes.

  The space 68p, the through hole 68s, and the groove 68m closed by the fixing member 67 are filled with a thermoplastic resin 149.

  According to such a configuration, since the substrate 65 can be positioned above the objective lens group 100, the tip 109 is made to be the optical axis compared to the case where the conventional substrate 65 is provided behind the objective lens group 100. It can be formed short in the direction K.

  In addition, since the substrate 65 and the solid-state imaging device 66 are provided in the distal end hard portion 68, the influence of stress applied to the substrate 65 and the solid-state imaging device 66 is reduced due to the bending of the bending portion 102 or the like. It is possible to prevent the substrate 65 and the solid-state imaging device 66 from being peeled off.

  Further, since the signal cable 60 is fixed to the distal end hard portion 68 by the fixing member 67, even if a torsional stress is applied to the signal cable 60 due to the bending of the bending portion 102, for example, the lead wire Separation at the connecting portion 59 can be reliably prevented.

  In addition, since the solid-state image sensor 66 is provided in the metal distal end hard portion 68, heat radiated from the solid-state image sensor 66 is easily radiated through the distal end hard portion 68. The heat dissipation of 66 is improved.

  Further, since the substrate 65 and the plurality of electronic components 64 are provided in the groove 68m, the heat radiated from the substrate 65 and the plurality of electronic components 64 is radiated by the extending portion 68e of the distal end hard portion 68. Since it becomes easy, the heat dissipation of the board | substrate 65 and the some electronic component 64 is improved.

The groove 68m may be provided below the objective lens group 100 in FIG. In this case, the substrate 65 and the plurality of electronic components 64 are positioned below the objective lens group 100, and the direction of light condensed by the objective lens group 100 is changed to the prism 61, for example, downward in FIG. Use what you want.

DESCRIPTION OF SYMBOLS 8 ... Moving lens 8A ... 1st moving lens 8B ... 2nd moving lens 18k ... Rear end of ring-shaped frame 21A ... Spring 21B ... Spring 21C ... Spring 21D ... Spring 21E ... Spring 22A ... Shape memory alloy 22B ... Shape memory alloy Alloy 27 fs ... Front end surface of outward flange portion 29 ... Moving member 30 ... Moving member 32 ... Screwing member 36 ... Housing member 36s2 ... Front end in housing member 36k2 ... Rear end in housing member 100 ... Objective lens group 116 ... Internal view Mirror 135 ... Tubular member 138 Shape memory alloy 180 ... Moving lens frame 180A ... First moving lens frame 180B ... Second moving lens frame 180C ... Third moving lens frame 180n ... Screw groove 221 ... Wire 221A ... Wire 221B ... wire 230 ... moving member 250A ... pulley 250B ... pulley 300A ... lens moving frame moving member 300B Lens moving frame moving member 301a ... Restricting member 301b ... Restricting member 330 ... Moving member 430 ... Moving member K ... Optical axis direction L1 ... First moving range L2 ... Second moving range

Claims (4)

In an endoscope in which a predetermined lens in an objective lens group for observing a subject constitutes a movable lens that is movable with respect to the optical axis direction of the objective lens group, whereby the observation magnification by the objective lens group can be varied.
A first moving lens constituting the objective lens group and changing the observation magnification below a predetermined observation magnification;
A second moving lens that constitutes the objective lens group and varies the observation magnification beyond the predetermined observation magnification;
A first moving lens frame that holds the first moving lens and is movable in the optical axis direction ;
A second moving lens frame that holds the second moving lens and is movable in the optical axis direction ;
A first moving member that moves the first moving lens frame within a first moving range by a first operation so as to vary the observation magnification below the predetermined observation magnification ;
The second moving lens frame is moved within a second movement range by a second operation in which the movement amount per unit time is smaller than the first operation so that the observation magnification is changed to be equal to or greater than the predetermined observation magnification. A second moving member to be moved at
An endoscope comprising: The first moving member moves the first moving lens frame in the first direction in the optical axis direction by the first operation,
The second moving member moves the second moving lens frame in a second direction opposite to the first direction in the optical axis direction by the second operation. The endoscope according to Item 1. Along with the first operation, the first moving lens frame is restricted from moving outside the first movement range in the optical axis direction, and with the second operation, the first movement lens frame is restricted to move outside the first movement range. The endoscope according to claim 1, further comprising a restricting member that restricts the second moving lens frame from moving outside the second moving range in the optical axis direction. . The amount of movement that the first moving lens frame can move in the optical axis direction within the first moving range by the first moving member is within the second moving range by the second moving member. The endoscope according to claim 1, wherein the second moving lens frame is different with respect to a moving amount that can move in the optical axis direction .

Images