JPH01114814A - Endoscope - Google Patents

Abstract

PURPOSE:To obtain an endoscope which can be easily subjected to fine adjustment by providing an objective lens on the inner periphery of a rotor at the end of an insertion part and moving the objective lens in the direction of an optical axis by means of the rotation of the rotor, which is caused by ultrasonic vibration. CONSTITUTION:An objective lens system 4 and a CCD 4a are provided at the end 3 of the insertion part 2 in the axial direction. The lens system 4 includes a varieter 5 as a moving lens and a compensator 6, and is fitted in circular lens frames 7 and 8. Spiral recessed parts 9 and 10 reversely facing the frames 7 and 8 are fitted in with the irregular part 12 on the inner periphery of the rotor 11. Furthermore, a stator 16 is provided on the outer periphery of the rotor 11. With such constitution, ultrasonic vibration is applied to the stator, and the rotor 11 is rotated. At such a time, the varieter 5 and the compensator 6 are led by a guide means 15, and are relatively moved in the direction of the optical axis so as to be focused all the time. Thus, the endoscopes which can be easily subjected to fine adjustment can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an endoscope in which a movable lens is provided within an objective lens system at the distal end of an insertion section.

[Prior Art] For example, an objective optical device of an endoscope disclosed in Japanese Patent Publication No. 61-53698 has a single movement within a zoom lens as an objective lens system provided in the rigid distal end of the insertion section of the endoscope. A lens is provided.

This movable lens is connected to an operating wire extended from the operating unit side, and by pushing and pulling this operating wire in the axial direction, the movable lens moves forward and backward in the optical axis direction and is adjusted to tele and wide conditions. It is now possible to do so.

[Problems to be Solved by the Invention] However, with the structure of the objective optical device described above, due to slack in the operating wire, etc., observation can only be made in the tele and wide positions when the operating wire is pulled and pushed. Even if the movable lens was located at other positions than these two points, it was difficult to bring the lens into focus.

This invention was made in view of the above circumstances, and an object thereof is to provide an endoscope having an objective lens system that allows fine adjustment by moving the movable lens without requiring an operating wire. do.

[Means and effects for solving the problems] This invention has the following features:
An objective lens system is provided at the tip of the insertion section, a rotor is provided on the outer periphery of at least one moving lens of the objective lens system, and the rotor is rotated in the circumferential direction between the rotor and the moving lens. As a result, the movable lens is moved back and forth in the optical axis direction, and the rotor is rotated by driving the stator, and the movable lens is moved in the optical axis direction by the guide means provided between the rotor and the movable lens. The endoscope is capable of reliably adjusting the amount of movement of the movable lens.

[Embodiment] A first embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In the rigid distal end portion 3 provided in the insertion section 2 of the endoscope 1 shown in FIG. 1, a perforation hole is bored in the axial direction and opened at the distal end surface. An objective lens system 4 is provided in this bored hole along the axial direction. Further inside this objective lens system 4, for example, a COD (solid-state image sensor) 4 is provided.
a are facing each other. Here, instead of the CCD 4a, the tip of an image guide extending to an operation section (not shown) may be opposed to the CCD 4a.

In the objective lens system 4, a variator 5 as a moving lens is provided, for example, located on the proximal side of the rigid tip section 3, and furthermore, on the distal side of the rigid tip section 3, the variator 5 is connected in the optical axis direction. A compensator 6 serving as a moving lens is provided facing the lens.

The variator 5 and compensator 6 as these movable lenses each have an annular lens frame 7.8.
The periphery is fitted.

Here, a compensator 6 is fitted into one lens frame 7, and a spiral concave-convex portion 9 is formed on the outer peripheral surface of the lens frame 7 in the optical axis direction.

Further, a variator 5 is fitted into the other lens frame 8, and a variator 5 is formed on the outer peripheral surface of the lens frame 8 in a spiral shape, for example, in the opposite direction to the concave and convex portions 9 formed on the one lens frame 7. A formed uneven portion 10 is provided.

A substantially cylindrical rotor 11 is provided on the outer peripheral side of these lens frames 7.8. This rotor 11 is provided concentrically with respect to the arrangement of the objective lens system 4, and has drive-side uneven portions 12 formed on its inner peripheral surface to be screwed into the respective uneven portions 9.10.

The drive-side concavo-convex portion 12 is configured so that both the variator 5 and the compensator 6 can be moved in respective required optical axis directions.

In other words, the drive-side uneven portion 12 is divided into a distal end side and a proximal side of the rotor 11, and the distal end side uneven portion 13 is screwed into the uneven portion 9 of the compensator 6. In addition, the uneven portion 14 on the base end side has the above-mentioned variator 5.
The concavo-convex portions 10 are screwed together.

The uneven portions 9 provided on the side of these lens frames 7 and 8
．． 10 and the drive-side uneven portion 12 provided on the rotor 11 side constitute a guide means 15. here,
The movement direction of each of the lens frames 7.8 is restricted only in the optical axis direction.

In other words, the supporting piece (not shown) of the lens frame 7 is connected to the rigid tip portion 3.
A pin body protrudes radially from this support piece, and this pin body is slidably fitted into a groove provided in the optical axis direction, so that the rotor 11 is rotated. However, the lens frame 7 is configured to be moved only in the optical axis direction without being rotated. Further, in the lens frame 8 of the variator 5, a support piece (not shown) is extended toward the proximal end side of the rigid distal end portion 3, and a pin body projects from this support piece in the radial direction, and this pin body is provided in the optical axis direction. The lens frame 8 is slidably fitted into the groove, and even when the rotor 11 is rotated, the lens frame 8 is
It is configured to be moved only in the optical axis direction without being rotated.

Further, a stator 16 is provided on the outer periphery of the rotor 11. The stator 16 is formed into a cylindrical shape and surrounds the rotor 11 concentrically and in a joined state. An ultrasonic power source (not shown) is connected to the stator 16, and the stator 16 is driven by application of voltage from the ultrasonic power source. When the stator 16 is driven, a longitudinal wave in the radial direction and a transverse wave in the circumferential direction are combined on the circumferential surface of the stator 16 that is joined to the rotor 11, and an elastic traveling wave that moves in an elliptical pattern is formed, and the stator The rotor 11 within the rotor 16 is rotated in the circumferential direction. In other words, the rotor 11 and stator 16 form an ultrasonic motor.

The above-mentioned ultrasonic power source is connected to the stator 16 via a control circuit (not shown), and if the stator 16 is controlled by this control circuit to generate only longitudinal waves in the stator 16, the rotor 11 will be completely destroyed. You can create a state where it does not rotate. Note that a switch for operating the control circuit is provided, for example, in an operation section (not shown) of the endoscope.

The stator 16 is fitted onto the inner peripheral surface of the distal end component 3 of the endoscope 1, and the rotor 11 side is rotated in the circumferential direction relative to the rigid distal end portion 3.

When the rotor 11 is rotated within the stator 16 configured in this way, the variator 5 and the compensator 6
are guided by the guide means 15 and moved relative to each other in the direction of the optical axis so that they are always in focus. In other words, even when moving from the wide position relationship shown in FIG. 1 to the tele position relationship shown in FIG. are controlled so that they match. Here, the rotor 11 having the uneven portion 13 on the distal end side and the uneven portion 14 on the proximal end side is rotated in one direction by the stator 16. These uneven parts 1
3.14 are carved with different spirals, and the concave and convex portions 9.10 of the lens frame 7.8 are guided in respective directions and moved in the telephoto and wide-angle directions.

The ultrasonic power source for driving the stator 16 is provided, for example, on the side of an operation section (not shown) of the endoscope 1, and the stator 16 is driven by application of voltage from the ultrasonic power source. Therefore, the moving force of the rotor 11 is stabilized,
Unlike conventionally used operating wires, uneven operation due to slack etc. is less likely to occur, and operability can be improved. moreover,
Since the variator 5 and the compensator 6 can be operated by one stator 16, it is easy to incorporate the above-described zoom mechanism into the compact rigid tip portion 3. In other words, in the past, the movable lens was moved using an operating wire, and when two or more movable lenses were to be operated, the structure became complicated, leading to an increase in the size of the rigid tip part, making it impossible to put it into practical use. By using the ultrasonic motor as described above, the rigid tip portion 3 can be held down to the same size as the conventional one while obtaining a reliable and stable adjustment force for advancing and retracting the movable lens. In addition, 2 tele and wide
A focused image can be obtained at any position between the points.

In the above embodiment, the helical directions of the helical uneven portions 9 and 10 and the driving side uneven portion 12 are not limited to the above-mentioned directions, but are designed so that the variator 5 and the compensator 6 can move as required. It is acceptable as long as it is configured.

The second embodiment of this invention will be described below with reference to FIGS. 3 and 4. However, since the basic structure of the rigid distal end portion 3 of the endoscope 1 is the same as that of the first embodiment, there are differences. The structure around the rotor 11 will be explained in detail.

The stator 16 shown in the figure has its outer circumferential surface fitted inside a hard end portion (not shown). This stator 16
is formed into a cylindrical shape, and its axis is provided along the axial direction of the rigid tip portion.

A concentrically formed cylindrical rotor 11 is provided on the inner peripheral surface of the stator 16, and the outer peripheral surface of the rotor 11 is provided so as to come into contact with the inner peripheral surface of the stator 16. ing.

The rotor 11 has, for example, symmetrical cam holes 17 formed in its upper circumferential surface and its lower circumferential surface, respectively. Each of the cam holes 17 is formed with a slope in the circumferential direction and the axial direction of the rotor 11. These cam holes 17
are vertically symmetrically formed on the distal and proximal sides of the rigid distal end portion, respectively, and the pin portion 18 of one lens frame 7 is slidably inserted into the distal end side of these cam holes 17. There is. The bin portions 18 are provided vertically on the outer periphery of the lens frame 7 with an interval of 180° between them.

The edge of the compensator 6 is fixed to and concentrically positioned on the lens frame 7, and is supported by the pin portion 18 so as to be movable forward and backward in the optical axis direction within the rotor 11.

Furthermore, pin portions 18 of the other lens frame 8 are slidably inserted into the upper and lower cam holes 17 located on the base end side of the rotor 11, respectively.

The edge of the variator 5 is fixed and concentrically positioned on the lens frame 8, and supports the rod within the rotor 11 so as to be movable forward and backward in the optical axis direction.

Furthermore, an ultrasonic power source is connected to the stator 16 via a control circuit (not shown). The rotor 11 is moved in the circumferential direction within the stator 16 by application of voltage from the ultrasonic power source.

When the stator 16 is driven, a longitudinal wave in the radial direction and a transverse wave in the circumferential direction are combined on the circumferential surface of the stator 16 that is joined to the rotor 11, and an elastic traveling wave that moves in an elliptical pattern is formed, and the stator The rotor 11 within the rotor 16 is rotated in the circumferential direction. In other words, the rotor 11 and stator 16 form an ultrasonic motor.

Then, each pin portion 18 of the lens frame 7.8 is moved back and forth in the axial direction along each inserted cam hole 17. Here, the cam hole 17 is formed so as to move both the variator 5 and the compensator 6 at the same time, so that the objective lens system 4 can always be kept in focus. . Although the cam holes 17 are vertically symmetrically provided in the rotor 11, the cam holes 17 are not limited thereto, and may be horizontally symmetrically provided, for example.

Note that the present invention is not limited only to the above-mentioned embodiments. For example, in each of the above embodiments, there are two moving lenses, the variator 5 and the compensator 6, but the present invention is not limited to this, and may include one or more moving lenses moved by an ultrasonic motor. Further, the guide means 15 is not limited to the above-mentioned guide means, and any guide means may be used as long as the variator 5 and the compensator 6 are moved in the optical axis direction when the rotor 11 is rotated.

[Effects of the Invention] As explained above, according to the present invention, a rotor is provided on the outer periphery of the movable lens, and a stator is provided on the outer periphery of the rotor, thereby forming an ultrasonic motor. Movement in the optical axis direction is ensured and fine adjustments can be easily made. Furthermore, by abolishing the conventional complicated zoom structure using the operating wire, it is possible to provide an endoscope that can simplify the structure inside the insertion section and achieve miniaturization.

[Brief explanation of the drawing]

1 and 2 show a first embodiment of the present invention. FIG. 1 is a side sectional view showing a schematic configuration of the tip component when the moving lens is in a wide state, and FIG. 3 and 4 are side sectional views showing a schematic configuration of the tip component in the telephoto state, and FIG. 3 shows a second embodiment of the present invention, and FIG. FIG. 4 is a sectional view of the rotor taken along the line IV--IV in FIG. 3. DESCRIPTION OF SYMBOLS 1... Endoscope, 2... Insertion part, 4... Objective lens system, 5... Variator (moving lens), 6... Compensator (moving lens), 11... Rotor ,1
5...Guiding means, 16...Stator. Applicant's agent Patent attorney Atsushi Tsuboi

Claims (1)

[Claims] In an endoscope in which a movable lens is provided in the objective lens system at the distal end of the insertion section, a rotor provided on the outer periphery of at least one movable lens, and a rotor provided between the rotor and the outer periphery of the movable lens. a guide means for moving the movable lens back and forth in the optical axis direction as the rotor is rotated in the circumferential direction; and a guide means provided on the outer periphery of the rotor to generate a vibration wave that rotationally moves the rotor in the circumferential direction. An endoscope characterized by comprising a stator.