JP2017029225A - Endoscope apparatus - Google Patents

Abstract

An object of the present invention is to limit an excessive bending angle depending on a bending direction indicated by an operation.
An operation unit can be operated by a user, detects the operation, and outputs an operation detection signal. A bending instruction unit generates a bending instruction signal based on the operation detection signal, and generates a first bending. The drive unit bends the distal end of the insertion unit in the first direction based on the bending instruction signal, and the second bending drive unit curves the distal end of the insertion unit in a second direction orthogonal to the first direction. When the bending instruction signal generated based on the operation detection signal indicates a bending instruction in a crossing direction that intersects both the first direction and the second direction, the bending instruction unit performs the first direction in the bending instruction in the crossing direction. Is less than the bending instruction amount in the first direction in the bending instruction in the first direction, and the bending instruction amount in the second direction in the bending instruction in the intersecting direction is in the bending instruction in the second direction. The bending instruction amount is adjusted to be smaller than the bending instruction amount in the second direction.
[Selection] Figure 2

Description

  The present invention relates to an endoscope apparatus including an insertion portion that is inserted into a subject.

  Endoscope apparatuses having a bending mechanism at the distal end of the insertion portion and having a variable visual field direction are widely known. By having a bending mechanism, it is possible to widely observe the space inside the subject without using a special optical system such as a fisheye lens, or using a general-purpose optical system, for example, a lens with a narrow viewing angle. . In addition, with such a bending mechanism, it is also possible to maintain high imaging resolution particularly in an observation area to be watched.

  Usually, a plurality of bending pieces are pivotally connected along the insertion direction on the distal end side (hereinafter, simply referred to as the distal end side) of the insertion portion of the endoscope apparatus in the up / down / left / right direction. In addition, a bending portion that can be bent by 360 ° is provided in a direction in which the four directions of the upper, lower, left, and right directions are combined. Specifically, the bending pieces are rotatably connected by rivets that constitute a plurality of rotating shafts that are located 90 ° apart from each other in the circumferential direction of the bending pieces in the insertion direction. In addition, the curve by the structure connected with the said rivet in the up-down-left-right direction or the arbitrary crossing directions which cross | intersect these directions so that rotation is possible is called biaxial bending.

  For example, Patent Document 1 discloses an endoscope apparatus including such a mechanism. The bending portion can be bent in the above-described direction by pulling any one or a plurality of the four wires inserted into the insertion portion in accordance with the user's operation.

JP 2006-218231 A

  However, in biaxial bending, the bending angle in the intersecting direction, which is the direction intersecting the up-down direction and the left-right direction, is larger than the up-down direction or the left-right direction, although the bending angle designated by the operation is common. Sometimes. In particular, the bending angle in the twist direction among the intersecting directions becomes the largest. The twist direction is an intermediate direction between the vertical direction and the horizontal direction.

  As described above, the conventional endoscope apparatus has a problem that the bending angle at which the bending portion is actually bent becomes larger than the instructed bending angle depending on the bending direction instructed by the operation. Since the actual bending angle is larger than the maximum bending angle at which the stress caused by bending (stress) is allowed, the load applied to the bending portion is biased to a specific part, and the bending portion itself is inserted into the bending portion. Stress components such as light guides and signal cables. This stress can cause deterioration and failure of these members. In addition, although the instructed bending angle is common, the actual bending angle varies depending on the bending direction, which may be a cause of a poor operational feeling for the user.

  The present invention has been made based on the above problems, and an object of the present invention is to provide an endoscope apparatus capable of limiting an excessive bending angle depending on a bending direction indicated by an operation.

  The present invention has been made to solve the above-described problems, and one aspect of the present invention is an operation that can be operated by an insertion unit and a user, detects the operation, and outputs an operation detection signal. A bending instruction section that generates a bending instruction signal based on the operation detection signal, a first bending driving section that bends the distal end of the insertion section in a first direction based on the bending instruction signal, and In the endoscope apparatus having a second bending drive unit that bends the distal end of the insertion unit in a second direction orthogonal to the first direction, the bending instruction unit generates a curve generated based on the operation detection signal. When the instruction signal indicates a bending instruction in a crossing direction that intersects both the first direction and the second direction, the bending instruction amount in the first direction in the bending direction in the crossing direction is in the first direction. The first direction in the curving instruction And the bending instruction amount in the second direction in the bending instruction in the intersecting direction is smaller than the bending instruction amount in the second direction in the bending instruction in the second direction. The endoscope apparatus is characterized in that the bending instruction amount is adjusted.

  Another aspect of the present invention is the endoscope apparatus described above, wherein the bending instruction unit is configured to change the first bending according to an angle with respect to the first direction or the second direction with respect to the intersecting direction. The adjustment amount for adjusting the bending instruction amount to the driving unit and the second bending driving unit is made different.

  Another aspect of the present invention is the above-described endoscope apparatus, in which the bending instruction unit adjusts the adjustment amount when the intersecting direction is an intermediate direction between the first direction and the second direction. It is characterized by a maximum.

Another aspect of the present invention is the above-described endoscope apparatus, wherein the bending instruction unit satisfies a curve satisfying (Equation 1) from a bending direction instruction value φ and a bending angle instruction value θ based on the bending instruction. An angle instruction value θ ′ is calculated, and the bending instruction signal is generated based on the bending angle instruction value θ ′.
θ ′ = θ · (1 − (− K · cos (4 · φ) + K)) (Formula 1)
However, K is a coefficient that defines the adjustment amount.

  Another aspect of the present invention is the endoscope apparatus described above, wherein the coefficient K is variable.

  Another aspect of the present invention is the above-described endoscopic device, which is separable and includes at least one of the operation unit and the insertion unit and a storage unit in which the coefficient K is stored in advance. It is characterized by comprising a unit.

  According to the present invention, it is possible to limit the bending angle from becoming excessive depending on the bending direction indicated by the operation.

It is a schematic block diagram which shows the structure of the endoscope apparatus which concerns on this embodiment. It is a schematic block diagram which shows the structure of the bending instruction | indication part and bending drive part which concern on this embodiment. It is a figure which shows the example of the bending instruction amount based on the operation amount. It is a figure which shows the example of the curve of the front-end | tip part of the insertion part which concerns on this embodiment. It is a figure which shows the example of the influence by the play of a wire. It is a figure which shows the example of rotation operation. It is a figure which shows the example of the curve to the twist direction of the front-end | tip part of the insertion part which concerns on this embodiment. It is a figure which shows the example of the influence by the play with respect to the curve characteristic of the insertion part which concerns on this embodiment. It is a figure which shows the example of the curve amount characteristic based on the curve instruction | indication amount which the curve amount adjustment part which concerns on this embodiment adjusted. It is a figure which shows the example of the input / output characteristic of an operation part. It is a figure which shows the example of the influence of the input / output characteristic of the operation amount with respect to the bending characteristic of the insertion part which concerns on this embodiment. It is a figure which shows the example of the bending instruction | indication amount which the bending amount adjustment part which concerns on this embodiment adjusted.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic block diagram showing a configuration of an endoscope apparatus 1 according to an embodiment of the present invention. The endoscope apparatus 1 can bend the distal end of the insertion portion 41 independently in the up / down (UD) direction and in the left / right (RL) direction based on an operation detection signal from the operation unit 11. A biaxial bending mechanism is provided.

  The endoscope apparatus 1 includes an operation unit 11, a bending instruction unit 12, a bending drive unit 14A, four wires 15, a bending unit 16, an illumination unit 21, a light guide 22, and an imaging unit 24. , Signal cable 25, CCD (Charge Coupled Device) signal processing unit 26, image signal processing unit 27, LCD (Liquid Crystal Display) 28, image recording unit 29, CPU (Central Processing Unit) 31, and memory 32, a bus 33, a power supply unit 34, and an insertion unit 41.

  In the endoscope apparatus 1, the bending instruction unit 12, the bending driving unit 14A, the illumination unit 21, the CCD signal processing unit 26, the image signal processing unit 27, the LCD 28, the image recording unit 29, the CPU 31, the memory 32, the bus 33, and The power supply unit 34 is accommodated in the housing of the main body unit 42. The operation unit 11 may be configured as a remote controller 51 that can be detached from the housing. Further, the bending instruction unit 12, the bending driving unit 14A, the illumination unit 21, the CCD signal processing unit 26, and the insertion unit 41 may be configured as a scope unit 52 in which these are integrated.

  The insertion portion 41 is formed of an elongated tube material whose one side is sufficiently longer than the other side. Of the both ends of the insertion portion 41 in the longitudinal direction, the proximal end is connected to the main body portion 42 and the distal end is opened. In the following description, the distal end of the insertion portion 41 is referred to as a distal end portion. An imaging unit 24 is installed at the tip, and the optical adapter 23 is detachable. The bending portion 16 is installed at a position sufficiently closer to the distal end than the proximal end of the insertion portion 41. Note that the wire 15, the light guide 22, and the signal cable 25 are inserted through the distal end portion in parallel with the longitudinal direction of the insertion portion 41.

  The bus 33 connects the bending instruction unit 12, the bending servo processing units 13-1 and 13-2 of the bending driving unit 14A, the illumination unit 21, the CCD signal processing unit 26, and the image signal processing unit 27. To do. Various signals and data can be transmitted and received between these components via the bus 33.

  The operation unit 11 can be operated by the user and detects the operation. The operation unit 11 generates an operation detection signal based on the detected operation. The operation unit 11 can independently detect an operation amount in the UD direction (hereinafter referred to as UD direction operation amount) and an operation amount in the RL direction (hereinafter referred to as RL direction operation amount). That is, the operation detection signal indicates the UD direction operation amount and the RL direction operation amount. The operation unit 11 outputs the generated operation detection signal to the bending instruction unit 12. The operation unit 11 is, for example, a joystick (JS: Joy-stick).

  The bending instruction unit 12 generates a bending instruction signal based on the operation detection signal input from the operation unit 11. The bending instruction signal includes a UD bending instruction signal indicating a bending instruction amount in the UD direction and an RL bending instruction signal indicating a bending instruction amount in the RL direction. The bending instruction unit 12 outputs the generated bending instruction signal to the bending drive unit 14A.

  The bending drive unit 14A bends the distal end portion based on the bending instruction signal input from the bending instruction unit 12. More specifically, the bending drive unit 14A bends the distal end portion in the RL direction based on the RL bending instruction signal, and bends the distal end portion in the UD direction based on the UD direction bending instruction signal. When bending in the RL direction, the bending drive unit 14 </ b> A pulls the R direction wire 15 </ b> R or the L direction wire 15 </ b> L out of the four wires 15. When bending in the UD direction, the bending drive unit 14 </ b> A pulls the U-direction wire 15 </ b> U or the D-direction wire 15 </ b> D out of the four wires 15. The configuration of the bending drive unit 14A will be described later.

  The four wires 15 are inserted into the insertion portion 41, each one end is fixed to the driving mechanism of the bending driving portion 14, and the other end is fixed to the bending portion 16. Of the four wires 15, the wires fixed at positions corresponding to the upper, lower, right, and left directions with respect to the observation field are the U-direction wire 15U, the D-direction wire 15D, and the R-direction wire 15R, respectively. , L direction wire 15L.

  The bending portion 16 is connected to the proximal end side of the distal end portion and includes a bending piece. With this configuration, the tip portion can be oriented in a desired direction by pulling the wire 15. When the bending drive unit 14A pulls the wire in one direction, the tip is bent in that direction. For example, when the bending drive unit 14A pulls the U-direction wire 15U, the distal end portion can be bent in the U direction.

  Of the four directions, the two wires 15 in the directions adjacent to each other (for example, the L direction and the U direction) are pulled simultaneously, so that the distal end portion is curved in the intersecting direction intersecting both of the two directions. However, among the four directions, the wires 15 in the respective directions (for example, the L-direction wire 15L and the R-direction wire 15R) are not pulled at the same time in the directions facing each other (for example, the L direction and the R direction). One-way wire 15 (for example, L-direction wire 15L) is pulled.

  The illumination unit 21 includes a light emitting element that emits light when supplied with electric power. The light-emitting element is, for example, a light-emitting diode (LED: Light Emitting Diode). The light emitted from the illumination unit 21 enters one end of the light guide 22.

  The light guide 22 includes an elongated member that transmits visible light. The light guide 22 includes, for example, an optical fiber. Light incident on one end of the light guide 22 is radiated from the other end of the light guide 22 located at the tip. The emitted light is incident on the hole 231 of the optical adapter 23.

  The optical adapter 23 has a hole 231 and an objective lens 232 on its main surface. The hole 231 transmits the light incident from the light guide 22. The transmitted light is reflected on the surface of the subject (not shown). Reflected light from the subject enters the objective lens 232 as incident light. Incident light passes through the objective lens 232. The optical adapter 23 is mainly used for the purpose of changing the range of observation depth and viewing angle.

The imaging unit 24 includes an incident lens 241 and a CCD image sensor 242.
Light that has passed through the objective lens 232 of the optical adapter 23 enters the incident lens 241 as incident light. The incident lens 241 converges incident light and forms an image of the subject on the imaging surface of the CCD image sensor 242.
The CCD image sensor 242 captures an image of the subject imaged on the imaging surface as an image, and generates a CCD signal indicating the captured image. The CCD signal is an electric signal obtained by photoelectrically converting incident light for each pixel arranged on the imaging surface, and has a signal value corresponding to the intensity of incident light irradiated for each pixel. The CCD image sensor 242 outputs the generated CCD signal to the CCD signal processing unit 26 via the signal cable 25.

  The CCD signal processing unit 26 samples the signal value of the CCD signal input from the CCD image sensor 242 via the signal cable 25 in a pixel arrangement order (for example, raster scan order) at a predetermined sampling period for each frame. An image signal indicating an image of each frame is generated. The CCD signal processing unit 26 outputs the generated image signal to the image signal processing unit 27.

  The image signal processing unit 27 performs predetermined image signal processing on the image signal input from the CCD signal processing unit 26. The predetermined image signal processing includes processes such as γ correction, YC conversion, distortion correction, and noise removal. The γ correction is a process of correcting the signal value for each pixel so that the change in luminance with respect to the change in the signal value for each pixel becomes constant. YC conversion is a process of generating a luminance image signal and a color difference image signal for an image signal corrected by γ correction. Distortion correction is a process for correcting a shift in coordinates for each pixel due to distortion caused by an optical system or the like for an image signal generated by YC conversion. Noise removal is a process of removing or suppressing various noise components superimposed on signal values of an image signal subjected to distortion correction.

  The image signal processing unit 27 outputs an image signal obtained by the image signal processing to the LCD 28. The image signal processing unit 27 compresses and encodes the obtained image signal to generate compressed image data, and stores the generated compressed image data in the image recording unit 29. The compression encoding method is, for example, a moving image compression method defined by ISO / IEC 23008-2 HEVC (High Efficiency Video Coding).

  The LCD 28 is a display device that displays an image indicated by the image signal input from the image signal processing unit 27.

  The image recording unit 29 includes a recording medium that records the compressed image data generated by the image signal processing unit 27.

  The CPU 31 controls the start, mode, timing, end, and the like of the operations of the bending instruction unit 12, the bending servo processing units 13-1, 13-2, the illumination unit 21, the CCD signal processing unit 26, and the image signal processing unit 27. To do. The CPU 31 may read a control program stored in advance in the memory 32 and control the operation of each component according to a command indicated by the read control program.

  The memory 32 stores various data generated by the CPU 31 and other components, various data used in processing by each component, and various programs. The memory 32 includes a storage medium such as a RAM (Random Access Memory), for example.

  The bus 33 is a transmission medium that connects various types of data so that they can be transmitted and received among the bending instruction unit 12, the bending drive unit 14A, the illumination unit 21, the CCD signal processing unit 26, the image signal processing unit 27, and the CPU 31.

  The power supply unit 34 supplies power for operating each component of the endoscope apparatus 1 to each component. The power supply unit 34 may include, for example, a power supply device such as an AC adapter that converts AC power from an AC (Alternating Current) power supply provided from the outside into DC power of a predetermined voltage.

(Configuration of bending instruction section)
Next, the configuration of the bending instruction unit 12 included in the endoscope apparatus 1 will be described.
FIG. 2 is a schematic block diagram illustrating the configuration of the bending instruction unit 12 and the bending driving unit 14A according to the present embodiment. The bending instruction unit 12 includes an instruction value adjusting unit 121 and a bending amount adjusting unit 122.

  The instruction value adjustment unit 121 includes a bending angle adjustment unit (RL direction) 121-1 and a bending angle adjustment unit (UD direction) 121-2. The bending angle adjustment units 121-1 and 121-2 generate correction instruction signals by performing correction processing and conversion processing at signal levels, respectively. The bending instruction signal includes a UD direction bending instruction signal and an RL direction bending instruction signal. The correction process includes, for example, removal of an offset value, a tilt error included in the operation amount, and the like. As the conversion processing, for example, the RL direction bending instruction signal x and the UD direction bending instruction signal respectively indicating the RL direction bending instruction amount x and the UD direction bending instruction amount y proportional to the corrected RL direction operation amount and UD direction operation amount, respectively. Processing to convert is included. When the bending drive unit 14A includes a servo mechanism and a motor as will be described later, the RL direction bending instruction amount x and the UD direction bending instruction amount y are the rotation angle instructions of the motor for bending the insertion unit 41 in the respective directions. Amount. The bending angle adjusting units 121-1 and 121-2 output the generated RL direction bending instruction signal and UD direction bending instruction signal to the bending amount adjusting unit 122, respectively.

  The bending amount adjusting unit 122 adjusts the RL direction bending instruction amount x indicated by the RL direction bending instruction signal from the bending angle adjusting unit 121-1 to the RL direction bending instruction amount x ′, and the bending amount adjusting unit 121-2 receives the RL direction bending instruction amount x ′. The UD direction bending instruction amount y indicated by the UD direction bending instruction signal is adjusted to the UD direction bending instruction amount y ′. In this adjustment, the bending amount adjusting unit 122, when the bending instruction signal indicates a bending instruction in the cross direction, the RL direction bending instruction amount x ′ and the UD direction satisfying both the following relationships (i) and (ii): A bending instruction amount y ′ is determined. (I) The RL direction bending instruction amount x ′ is set to be smaller than the RL direction bending instruction amount x ′ when the bending instruction signal indicates a bending instruction in the RL direction. (Ii) The UD direction bending instruction amount y ′ is set smaller than the UD direction bending instruction amount y ′ when the bending instruction signal indicates a bending instruction in the UD direction. The intersecting direction is a direction that intersects both the UD direction and the RL direction. The bend amount adjusting unit 122 can detect that the bend instruction signal indicates a bend instruction in the intersecting direction when both the RL bend instruction amount x and the UD bend instruction amount y have values that are not significantly zero. .

  Here, the bending amount adjusting unit 122 changes the adjustment amount of the RL direction bending instruction amount x ′ and the UD direction bending instruction amount y ′ according to the bending direction specified by the bending instruction. The bending amount adjustment unit 122 increases the adjustment amount as the angle formed between the RL direction or the UD direction and the indicated direction is larger. The bending amount adjustment unit 122 maximizes the adjustment amount when the direction indicated by the bending instruction indicates the twist direction. The twist direction is an intermediate angle between the RL direction and the UD direction.

Specifically, the bending amount adjusting unit 122 calculates a bending direction instruction value φ and a bending angle instruction value θ that satisfy the relationship of the expressions (1) and (2) from the RL direction bending instruction amount x and the UD direction bending instruction amount y. calculate.
φ = tan ⁻¹ (y / x) (1)
θ = (x ² + y ² ) ^1/2 (2)
For example, when the operation unit 11 is a joystick, the bending direction instruction value φ is given based on a tilt direction that is a direction in which the operation rod 111 (described later) is tilted. The bending angle instruction value θ is given as an angle proportional to the tilt angle of the operating rod 111 in the tilt direction.

Then, the bending amount adjusting unit 122 calculates the bending angle instruction value θ ′ adjusted so as to satisfy the relationship of Expression (3) from the calculated bending direction instruction value φ and the bending angle instruction value θ.
θ ′ = θ · (1 − (− K · cos (4 · φ) + K)) (3)
In equation (3), K represents a predetermined coefficient that defines the amount of adjustment. K is a real number larger than 0 and smaller than 0.5. The second term of Expression (3) indicates the adjustment amount of the bending angle instruction value θ. This adjustment amount is a periodic function having a period four times the bending direction instruction value φ. When the bending direction instruction value φ indicates the RL direction or the UD direction, the adjustment amount is the smallest and the bending angle instruction value θ ′ is the largest. In this case, the adjustment amount is zero. When the bending direction instruction value φ indicates the twist direction, the adjustment amount is the largest and the bending angle instruction value θ ′ is the smallest. In this case, the maximum adjustment amount is 2 · K.

  The coefficient K may be variable. For example, the coefficient K may be larger as the rigidity of the insertion portion 41 is lower. This is because the bending angle tends to increase when the insertion portion 41 is bent in the twist direction. In addition, the rigidity of the insertion part 41 is so low that a diameter is small, when a material is the same. Therefore, the coefficient K may be different depending on the size and material of each insertion portion 41. Note that the bending amount adjustment unit 122 may be able to set the coefficient K in accordance with an operation input by the user.

The bending amount adjustment unit 122 uses the bending direction instruction value φ ′ and the calculated bending angle instruction value θ ′ to satisfy both the equations (4) and (5), and the RL direction bending instruction amount x ′ and the UD direction bending instruction amount y ′. Is calculated.
x ′ = θ′cosφ (4)
y ′ = θ′sinφ (5)
Then, the bending amount adjusting unit 122 receives the RL direction bending instruction signal indicating the calculated RL direction bending instruction amount x ′ and the UD direction bending instruction signal indicating the UD direction bending instruction amount y ′, respectively. The data is output to the servo processing units 13-1 and 13-2. An example of the curve amount characteristic adjusted by the curve amount adjusting unit 122 will be described later.

(Configuration of bending drive unit)
Next, the configuration of the bending drive unit 14A will be described. The bending drive unit 14A includes a bending servo processing unit (RL direction) 13-1, a bending servo processing unit (UD direction) 13-2, a bending driving unit (RL direction) 14-1, and a bending driving unit (UD direction). ) 14-2.
The bending servo processing unit 13-1 operates with respect to the operation of the bending driving unit 14-1 based on the RL direction bending instruction signal input from the bending amount adjusting unit 122 and the RL direction detection signal input from the bending driving unit 14. Servo control is performed. The RL direction detection signal is a signal indicating the amount of bending in the RL direction detected by the bending drive unit 14-1 (hereinafter referred to as the RL direction bending detection amount). The bending servo processing unit 13-1 calculates the difference value of the RL direction bending detection amount that is the reference value from the RL direction bending instruction amount x ′ that is the target value, as the RL direction driving amount, and indicates the RL direction driving amount. The drive signal is output to the bending drive unit 14-1.

  The bending servo processing unit 13-2 operates the bending driving unit 14-2 based on the UD direction bending instruction signal input from the bending amount adjusting unit 122 and the UD direction detection signal input from the bending driving unit 14. Servo control is performed. The UD direction detection signal is a signal indicating the UD direction bending detection amount detected by the bending drive unit 14-2. The bending servo processing unit 13-2 calculates the difference value of the UD direction bending detection amount as the reference value from the UD direction bending instruction amount y ′ as the target value as the UD direction driving amount, and displays the UD direction driving amount in the UD direction. The drive signal is output to the bending drive unit 14-2.

  The bending drive unit 14-1 bends the tip in the RL direction based on the RL direction drive signal input from the bending servo processing unit 13-1. The bending drive unit 14-1 includes, for example, a motor 141 (FIG. 5) and a potentiometer (not shown). When the RL direction drive amount indicated by the RL direction drive signal is larger than 0, the bending drive unit 14-1 pulls the R direction wire 15R by rotating the motor 141 so as to be displaced by the RL direction drive amount. When the RL direction drive amount is smaller than 0, the bending drive unit 14-1 pulls the L direction wire 15L so as to be displaced by the absolute value of the RL direction drive amount. The potentiometer detects, for example, the rotation angle of the motor 141 as the RL direction bending detection amount. The rotation angle of the motor 141 corresponds to the bending angle of the tip. The bending drive unit 14-1 outputs an RL direction detection signal indicating the detected RL direction bending detection amount to the bending servo processing unit 13-1.

  The bending drive unit 14-2 bends the tip in the UD direction based on the UD direction drive signal input from the bending servo processing unit 13-2. The bending drive unit 14-2 has the same configuration as the bending drive unit 14-1. However, the bending drive unit 14-2 pulls the U-direction wire 15U or the D-direction wire 15D so as to be displaced by the UD direction drive amount indicated by the UD direction drive signal. The bending drive unit 14-2 generates a UD direction detection signal indicating the detected UD direction bending detection amount. The bending drive unit 14-2 outputs the generated UD direction detection signal to the bending servo processing unit 13-2.

  The endoscope apparatus 1 has an arbitrary configuration including a UD direction, an RD direction, or an intermediate twist direction in accordance with a bending instruction value instructed by a user's operation of the operation unit 11 depending on the configuration. Can be curved in the crossing direction. In addition, the endoscope apparatus 1 can rotate the bending direction of the distal end portion around a predetermined rotation axis in accordance with a rotation operation instructing rotation in the bending direction.

(Operation detection signal)
Next, the operation amount indicated by the operation detection signal will be described. In the following description, the operation unit 11 is a biaxial JS as an example. As illustrated in FIG. 3A, the operation unit 11 includes an operation rod 111 having one end supported by a pedestal 113. A regulating member 112 having a hole through which the operation rod 111 is inserted is provided at the center of the main surface of the pedestal 113. The shape of the hole is circular with respect to the main surface view direction of the pedestal 113, and the diameter thereof is larger than the diameter of the operating rod 111. When the operation is not performed, the operation rod 111 is disposed on the central axis z that passes through the center of the hole and is perpendicular to the main surface of the pedestal 113.

  The operation rod 111 can be tilted by a user operation. By increasing the operation amount, when the tilt angle from the central axis z (corresponding to the bending angle instruction value θ) increases, a part of the tilted operating rod 111 comes into contact with the hole of the regulating member 112. The tilt angle that is restricted when a part of the operating rod 111 is in contact with the hole is referred to as a maximum tilt angle. Since the hole has a circular shape, the maximum tilt angle is common regardless of the tilt direction (corresponding to the bending direction instruction value φ) as shown in FIG. Here, the tilt angle is an angle formed by the longitudinal direction of the tilted operating rod 111 and the central axis z. The tilt direction is a direction in which the longitudinal direction of the tilted operating rod 111 is projected onto the xy plane. The xy plane is a plane orthogonal to the central axis z.

  In operation, one direction parallel to the xy plane is the R direction or L direction, and the other direction perpendicular to the R direction or L direction is the U direction or D direction on the xy plane. The RL direction is a general term for the R direction, which is the opposite direction to the R direction. The UD direction is a general term for the U direction and the D direction which is the opposite direction. In the example shown in FIG. 3A, the R direction is the right direction with respect to the drawing, but it does not necessarily have to be the right direction with respect to the user. On the other hand, although the U direction is an upward direction with respect to the drawing, the U direction is not necessarily the reverse direction of the vertical direction and may not be a direction away from the front of the user. As long as the RL direction operation amount and the UD direction operation amount can be instructed in parallel by the operation, the RL direction and the UD direction may be orthogonal or may not be orthogonal as the operation direction.

  The operation unit 11 includes, for example, a tilt angle in the UD direction (hereinafter referred to as a UD direction tilt angle) and a tilt angle in the RL direction (hereinafter referred to as RL) as the UD direction operation amount and the RL direction operation amount, respectively. It may be configured to include a variable resistor whose electrical resistance value changes by moving the contact point according to the direction tilt angle). With this configuration, the instruction value adjustment unit 121 determines the UD direction bending instruction amount x and the RL direction bending instruction amount y that are proportional to the UD direction tilt angle and the RL direction tilt angle, respectively. In the following description, for the sake of simplicity, it is assumed that the bending instruction amount is equal to the operation amount. In that case, the RL direction tilt angle and the UD direction tilt angle are given as the UD direction curve instruction amount x and the RL direction curve instruction amount y, respectively, and the tilt angle and the tilt direction are respectively the bending angle instruction value θ and the bending direction. It is given as an instruction value φ.

When the maximum inclination angle is given as bending operation amount, the bending angle theta _c of the distal end portion is maximized. As shown in FIG. 4A, the bending angle θ _c is an angle formed between the longitudinal direction z _c of the insertion portion 41 and the direction of the curved distal end portion in a non-curved state. Ideally, as shown in FIG. 4B, the bending angle θ _c of the tip is equal to the bending angle instruction value θ, and the maximum bending angle θ _c is controlled to be constant regardless of the bending direction φ _c. It is desirable.

The bending direction, the longitudinal direction of the curved tip portion is a direction obtained by projecting the vertical x _c y _c plane in the direction z _c. In the bending of the tip, a x _c y _c a direction R direction or the L direction parallel to the plane, x _c y _c perpendicular other direction in the R direction or the L direction in the plane in the U direction or the D direction is there. In the example shown in FIG. 4A, the R direction is the right direction with respect to the drawing, but may not be the same direction as the R direction in the operation. On the other hand, the U direction is an upward direction with respect to the drawing, but may not be the same direction as the R direction in the operation. The RL direction and the UD direction in the bending of the tip may be associated with the RL direction and the UD direction in the operation. For example, the RL direction and the UD direction in the curvature of the tip may be the horizontal direction and the vertical direction of the imaging coordinate system with the imaging unit 24 as a reference.

(Effect of wire play)
In the conventional endoscope apparatus, the bending operation using the wire 15 described above has a problem described below. As shown in FIG. 5B, between the wire 15 and the wire winding part 142 connecting the motor 141 of the bending drive part 14, a certain amount of wire 15 is attached to the wire 15 for the purpose of protecting the wire 15. Generally, a play portion is provided. If no play portion is provided, external stress may be applied to the bending portion 16 provided in the insertion portion 41. In that case, a high load may be generated on the wire 15.

  On the other hand, hysteresis characteristics may occur in relation to the bending angle of the tip portion actually obtained with respect to the bending instruction due to the play provided on the wire 15 and the friction between the wire 15 and the wire winding portion 142. FIG. 5A shows an example of the relationship between the UD direction bending instruction amount indicated by the bending instruction signal and the UD direction displacement, that is, the bending angle in the UD direction. As shown in FIG. 5A, when the UD direction bending instruction amount increases (corresponding to the operation of tilting the operating rod 111 from the D direction to the U direction), the UD direction bending instruction amount decreases (operation). The displacement in the UD direction is smaller than that in the case of the same UD direction bending instruction amount than the operation of tilting the ridge 111 from the U direction to the D direction. The difference in displacement in the UD direction is that the motor 141 of the bending drive unit 14 idles with respect to a displacement corresponding to play.

  Here, it is assumed that an operation (hereinafter referred to as a rotation operation) is performed to rotate the operation rod 111 around the central axis z while maintaining a constant tilt angle (for example, the maximum tilt angle) at a constant rotational speed. (FIG. 6A). As shown in FIG. 6B, the bending angle instruction value θ is kept constant, and the bending direction instruction value φ changes at a constant speed. This operation corresponds to the operation of reciprocating the operating rod 111 in the RL direction and the operation reciprocating in the UD direction being parallel with a common amplitude and a phase difference of 90 degrees. In that case, due to the play provided in the wire 15, there may be a period in which the actual bending angle is larger than the bending angle (displacement) expected by the bending instruction amount specified by the operation. In other words, if the bending amount adjusting unit 122 according to the present embodiment is not provided, when the bending direction of the distal end portion is the twist direction as shown in FIG. 7, the bending angle is larger than the bending angle in the other bending directions. Become.

As shown in FIG. 8A, the displacement RL21 in the RL direction and the displacement UD21 in the UD direction when play is provided are the displacement RL11 in the RL direction and displacement UD11 in the UD direction when no play is provided, respectively. Later than. Further, after the displacement RL21 and the displacement UD21 reach the maximum value or the minimum value, the values are maintained for a predetermined time by idling of the motor, and then decrease or increase. Therefore, bending angle θ21 when bending direction phi _c is cross direction, the bending direction phi _c is larger than the bending angle θ21 when it is RL direction or UD direction (Figure 8 (b)).

In particular, if the bending direction phi _c is the twist direction, bending angle θ21 is maximized. The bending angle θ21 when play is provided is larger than the bending angle θ11 when play is not provided and the bending angle when a bending instruction is given only in one axial direction. Although the tilt angle (operation angle) is constant, the difference in the bending angle depending on the tilt direction (operation direction) can cause a deterioration in the operational feeling of the user. In addition, an excessive bending angle caused by the bending direction may cause stress on the light guide 22 and the signal cable 25 that pass through the insertion portion 41, and may cause deterioration or failure of the device.

(Example of curvature characteristics)
Next, an example of the curve amount characteristic adjusted by the curve amount adjusting unit 122 according to the present embodiment will be described. FIG. 9 is a diagram illustrating an example of a curve amount characteristic based on the curve instruction amount adjusted by the curve amount adjustment unit 122 according to the present embodiment. In the example shown in FIG. 9, K is 0.05.

  In FIGS. 9A and 9B, a curve LF31 indicates the curve direction dependency of the adjustment characteristic α. The adjustment characteristic α is given by (1 − (− K · cos (4 · φ) + K)) on the right side of the equation (3). When the bending direction instruction value φ is 0 °, 90 °, 180 °, 270 °, the adjustment characteristic α is 1 (no adjustment). Therefore, when the bending direction instruction value φ indicates the RL direction or the UD direction, the bending angle instruction value θ is not adjusted. When the bending direction instruction value φ indicates an intersecting direction intersecting the RL direction and the UD direction, the bending angle instruction value θ is adjusted to be smaller. When the bending direction instruction value θ is 45 °, 135 °, 205 °, or 315 °, the adjustment characteristic α is 0.9 (minimum value). That is, when the bending direction instruction value φ indicates the twist direction, the adjustment amount of the bending angle instruction value θ is the largest.

  FIG. 9C shows an example of the bending angle θ31 obtained by adjusting the bending direction instruction value φ and the bending angle instruction value θ by the bending amount adjusting unit 122 when play is provided. The bending angle θ31 is closer to the bending angle θ11 that is constant regardless of the bending direction instruction value φ than the bending angle θ21 before adjustment. This indicates that the error of the bending angle affected by play from the bending angle instruction value is reduced. The bending angle θ31 in the RL direction and the UD direction that are hardly affected by play is not adjusted, and the adjustment amount that gives the bending angle θ31 in the twist direction most affected by play is adjusted to be the largest.

(Effects of output characteristics)
Further, in the conventional endoscope apparatus, another reason that the bending angle varies depending on the operation direction is that the bending operation amount output from the operation unit 11 is not completely proportional to the bending operation amount to the operation unit 11. Can be mentioned. Thus, even when a rotation operation is performed, a bending instruction signal that gives a constant bending angle instruction value θ may not be input to the bending servo processing units 13-1 and 13-2 regardless of the bending direction.

  For example, the operation unit 11 outputs an operation detection signal indicating the UD direction operation amount (or RL direction operation amount) proportional to the UD direction tilt angle or the RL direction tilt angle of the operation rod 111 as described above. An operation range of the operating rod 111, for example, a range from the maximum tilt angle in the U direction to the maximum tilt angle in the D direction may include a range in which the output UD direction operation amount does not change. In this range, the resistance value does not change in proportion to the change in the tilt angle in the UD direction. In the example shown in FIG. 10, the UD direction operation amount is substantially constant in a region (dead zone) where the UD direction tilt angle is closer to the maximum tilt angle than 0. The dead zone may be intentionally provided as a specification of the operation unit 11.

  Therefore, as shown in FIG. 11A, the UD direction bending instruction amount UD41 and the RL direction instruction amount RL41 do not become a cosine function or a sine function in the tilt direction of the operating rod 111. There are regions in the tilt direction in which the UD direction bending instruction amount UD41 and the RL direction bending instruction amount RL41 are substantially constant regardless of the change in the tilt direction of the operating rod 111. This region is a region where the tilt direction is within the range of the dead zone, or the tilt angle of the RL direction or the tilt angle of the UD direction. In FIG. 11B, the relationship between the bending direction instruction value φ and the bending angle instruction value θ41 given from the UD direction bending instruction amount UD41 and the RL direction bending instruction amount RL41 is substantially represented by a rectangle. The bending angle instruction value θ41 varies depending on the bending direction instruction value φ. The bending angle instruction value θ41 is the smallest when the bending direction instruction value φ indicates the RL direction or the UD direction, and is the largest when the bending direction instruction value φ indicates the twist direction.

The characteristics of such bending angle instruction value θ41 is bending angle theta _c of tip cause vary depending on the bending direction phi _c. Even in this case, although the tilt angle is constant, the bending angle varies depending on the tilt direction, so that the user's operational feeling is impaired. In addition, an excessive bending angle caused by the bending direction can cause deterioration or failure of the device.

(Example of bending instruction value)
Next, an example of the bending instruction amount adjusted by the bending amount adjustment unit 122 according to the present embodiment will be described. FIG. 12 is a diagram illustrating an example of the bending instruction amount adjusted by the bending amount adjustment unit 122 according to the present embodiment. In the example shown in FIG. 12, K is 0.145.
Unlike the bending angle instruction value θ41 before adjustment, the adjusted bending angle instruction value θ51 is substantially constant regardless of the bending direction instruction value φ. The bending angle instruction value θ41 that has been excessive in the intersecting direction, particularly the twist direction, decreases, and the bending angle instruction value θ41 in the RL direction or the UD direction is maintained. Therefore, the bending angle of the tip is almost constant regardless of the bending direction. This indicates that the influence of the output characteristics of the operation unit 11 is reduced or eliminated.

  In the above description, the influence due to the play of the wire 15 and the influence due to the output characteristic of the operation unit 11 are individually considered. However, both influences may appear in an actual environment. Even in this case, the bending amount adjusting unit 122 adjusts the bending direction instruction value φ and the bending angle instruction value θ based on the equation (3), thereby making the bending angle of the tip end portion substantially constant regardless of the bending direction. can do. Further, by changing the coefficient K, the adjustment amount of the bending angle and the bending direction can be easily changed.

  As described above, the endoscope apparatus 1 according to the present embodiment includes the insertion unit 41, the operation unit 11 that can be operated by the user, detects the operation, and outputs an operation detection signal. A bending instruction unit 12 that generates a bending instruction signal based on the operation detection signal. Further, the endoscope apparatus 1 bends the distal end of the insertion portion 41 in the RL direction based on the bending instruction signal, and bends the distal end of the insertion portion 41 in the UD direction based on the bending instruction signal. A bending drive unit 14-2. Further, the bending instruction unit 12, when the bending instruction signal generated based on the operation detection signal indicates a bending instruction in a crossing direction intersecting both the RL direction and the UD direction, in the RL direction in the crossing direction bending instruction. The bending instruction amount is smaller than the RL direction bending instruction amount in the bending instruction in the RL direction, and the UD direction bending instruction amount in the intersecting direction bending instruction is larger than the UD direction bending instruction amount in the bending instruction in the UD direction. The RL direction bending instruction amount and the UD direction bending instruction amount are adjusted so as to be smaller.

  With this configuration, the phenomenon that the bending angle in the intersecting direction of the distal end of the insertion portion 41 increases the bending angle in the RL direction or the UD direction is alleviated, so the bending angle becomes excessive due to the bending direction indicated by the operation. Can be restricted. Therefore, it is possible to improve the operational feeling by the user. Moreover, since the load to the insertion part 41 is reduced by restricting an excessive bending angle depending on the bending direction, it is possible to prevent deterioration or failure of the device.

When the direction instructed by the bending instruction is a crossing direction, the bending instructing unit 12 applies to the bending driving unit 14-1 and the bending driving unit 14-2 according to an angle with respect to the RL direction or the UD direction. The adjustment amount for adjusting the bending instruction amount is varied.
With this configuration, the bending angle in the intersecting direction of the distal end of the insertion portion 41 can be varied according to the bending direction, so that the dependency of the bending angle on the bending direction can be reduced.

Further, the drive control unit 12A is characterized in that the adjustment amount is maximized when the direction indicated by the bending instruction is a twist direction intermediate between the RL direction and the UD direction.
With this configuration, when the bending direction of the distal end of the insertion portion 41 is the twist direction, it is possible to reduce the bending direction dependency where the bending angle is the largest.

Further, the drive control unit 12A calculates a bending angle instruction value θ ′ satisfying the expression (3) from the bending direction instruction value φ and the bending angle instruction value θ based on the bending instruction, and based on the calculated bending angle instruction value θ ′. Generating a bending instruction signal.
With this configuration, the bending angle instruction value θ that is instructed by a bending instruction is adjusted by a simple calculation, so that the bending direction dependency of the bending angle is reduced without complicated calculation or main configuration change. Can do. Further, since Equation (3) is a continuous function with respect to the bending direction instruction value φ, the bending angle instruction value θ ′ calculated according to the sequential change (for example, rotation operation) of the bending direction instruction value φ changes rapidly. do not do. Since a sudden change in the direction of the distal end of the insertion portion 41 is avoided, safety is ensured and the load on the insertion portion 41 can be reduced.

Further, in the expression (3), the coefficient K is variable.
With this configuration, the adjustment amount according to the bending direction of the bending angle at the distal end of the insertion portion 41 can be easily changed. For this reason, the work burden for setting the adjustment amount is reduced.

In addition, the endoscope apparatus 1 includes a remote controller 51 and / or a scope unit 52 as a separable unit including an operation unit 11 and a storage unit in which a coefficient K is stored in advance. Also good.
With this configuration, when the operation unit 11 or the scope unit 52 is replaced, the coefficient K corresponding to the characteristics can be set in the bending instruction unit 12 without a user operation. At this time, in the configuration of the endoscope apparatus 1, the common part remaining in the main body 42 can be operated with a certain characteristic regardless of whether the operation unit 11 or the scope unit 52 is replaced.

In the above-described embodiment, the case where the operation unit 11 is mainly biaxial JS is taken as an example, but the present invention is not limited to this. The operation part 11 should just be comprised including the apparatus which can detect the operation amount to RL direction and the operation amount to UD direction by a user's operation. The operation unit 11 may be a pointing device such as a trackball or a mouse, for example.
In the above-described embodiment, the case where the bending drive unit 14A has a servo motor including the bending servo processing units 13-1 and 13-2 and the bending drive units 14-1 and 14-2 is mainly exemplified. This is not a limitation. The bending drive unit 14A may include a stepping motor instead of the servo motor.

  In the above-described embodiment, the bending angle adjustment unit 121-1 acquires the RL direction bending instruction amount x proportional to (or equal to) the RL direction operation amount indicated by the operation detection signal input from the operation unit 11. Although an example, it is not limited to this. The bending angle adjustment unit 121-1 only needs to determine the RL direction bending instruction amount x based on the RL direction operation amount. For example, when a predetermined operation mode is instructed, the bending angle adjustment unit 121-1 increases the RL direction bending instruction amount x at a predetermined increase rate while the RL direction operation amount is equal to or greater than a predetermined R direction threshold. The RL direction bending instruction amount x may be decreased at a predetermined decrease rate while the RL direction operation value is equal to or less than a predetermined L direction threshold. The bending angle adjustment unit 121-2 may determine the UD direction bending instruction amount y based on the UD direction operation amount using the same method as the bending angle adjustment unit 121-1.

  In the above-described embodiment, the bending amount adjusting unit 122 has adjusted the bending direction instruction value φ and the bending angle instruction value θ so as to satisfy the relationship of Expression (3). I can't. The bending amount adjustment unit 122 only needs to be adjusted so that the adjustment amount of the bending angle in the RL direction and the UD direction becomes 0 and the adjustment amount of the bending angle in the twist direction becomes the maximum. For example, the bending amount adjusting unit 122 may use a triangular function (triangular wave) that gives a minimum value in the twist direction when the cycle of the bending direction instruction value φ is 90 ° as the adjustment amount. Also in this case, the bending amount adjustment unit 122 adjusts the bending angle instruction value θ by a simple calculation, and the adjustment amount can be easily changed. Further, the bending amount adjusting unit 122 is a function obtained by weighting and adding a cosine function having a period that is an integral multiple of 4 with a predetermined weight coefficient in addition to a cosine function having a period of 4 as shown in Expression (3). (Fourier expansion) may be determined as the adjustment amount. Thereby, the bending direction dependence of the bending angle of the tip portion can be expressed with higher accuracy.

  Note that a part of the endoscope apparatus 1 according to the above-described embodiment, for example, the bending instruction unit 12 and the image signal processing unit 27 may be realized by a computer. In that case, the program for realizing the control function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by the computer system and executed. Here, the “computer system” is a computer system built in the endoscope apparatus 1 and includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” is a medium that dynamically holds a program for a short time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, In this case, a volatile memory inside a computer system that serves as a server or a client may be included that holds a program for a certain period of time. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  Further, part or all of the endoscope apparatus 1 according to the above-described embodiment may be realized as an integrated circuit such as an LSI (Large Scale Integration). Each functional block of the endoscope apparatus 1 may be individually made into a processor, or a part or all of them may be integrated into a processor. Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. Further, in the case where an integrated circuit technology that replaces LSI appears due to progress in semiconductor technology, an integrated circuit based on the technology may be used.

In the above-described embodiment, a part of the operation unit 11 may be stored in the main body 42 of the endoscope device 1. If the endoscope apparatus 1 can receive an operation instruction signal generated in response to a user operation, the operation unit 11 may be omitted.
As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment and its modification. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention.
Further, the present invention is not limited by the above description, and is limited only by the scope of the appended claims.

DESCRIPTION OF SYMBOLS 1 ... Endoscope apparatus, 11 ... Operation part, 111 ... Operation rod, 112 ... Restriction member, 113 ... Base, 12 ... Curve instruction | indication part, 121 ... Instruction value adjustment part, 121-1, 121-2 ... Curve angle adjustment 122, bending amount adjusting unit, 13-1, 13-2 ... bending servo processing unit, 14A, 14-1, 14-2 ... bending driving unit, 141 ... motor, 142 ... wire winding unit, 15 ... wire 15R ... R direction wire, 15L ... L direction wire, 15U ... U direction wire, 15D ... D direction wire, 16 ... curved portion, 21 ... illuminating portion, 22 ... light guide, 23 ... optical adapter, 231 ... hole, 232: objective lens, 24: imaging unit, 241 ... incident lens, 242 ... CCD image sensor, 25 ... signal cable, 26 ... CCD signal processing unit, 27 ... image signal processing unit, 28 ... LCD, 29 Image recording unit, 31 ... CPU, 32 ... memory, 33 ... bus, 34 ... power unit, 41 ... insertion portion, 42 ... main body portion

Claims (6)

An insertion part;
An operation unit that can be operated by the user, detects the operation, and outputs an operation detection signal;
A bending instruction unit that generates a bending instruction signal based on the operation detection signal;
Based on the bending instruction signal, a first bending drive section that bends the distal end of the insertion section in a first direction, and a second bending drive that bends the distal end of the insertion section in a second direction orthogonal to the first direction. And
In an endoscope apparatus having
The bending instruction section
When the bending instruction signal generated based on the operation detection signal indicates a bending instruction in an intersecting direction that intersects both the first direction and the second direction,
The bending instruction amount in the first direction in the bending instruction in the intersecting direction is smaller than the bending instruction amount in the first direction in the bending instruction in the first direction, and
The bending instruction amount in the second direction in the bending instruction in the intersecting direction is smaller than the bending instruction amount in the second direction in the bending instruction in the second direction.
Adjusting the bending instruction amount;
An endoscope apparatus characterized by that. The bending instruction unit adjusts an amount of adjustment for adjusting a bending instruction amount to the first bending driving unit and the second bending driving unit according to an angle with respect to the first direction or the second direction in the intersecting direction. The endoscope apparatus according to claim 1, wherein the endoscope apparatus is made different. The endoscope apparatus according to claim 2, wherein the bending instruction unit maximizes the adjustment amount when the intersecting direction is an intermediate direction between the first direction and the second direction. The bending instruction section
A bending angle instruction value θ ′ satisfying (Equation 1) is calculated from a bending direction instruction value φ and a bending angle instruction value θ based on the bending instruction, and the bending instruction signal is generated based on the bending angle instruction value θ ′. The endoscope apparatus according to any one of claims 1 to 3, wherein θ ′ = θ · (1 − (− K · cos (4 · φ) + K)) (Expression 1)
However, K is a coefficient that defines the adjustment amount.   The endoscope apparatus according to claim 4, wherein the coefficient K is variable.   The endoscope apparatus includes a separable unit including at least one of the operation unit and the insertion unit, and a storage unit in which the coefficient K is stored in advance. The endoscope apparatus according to Item 5.

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