JPH03295532A - Shape measuring endoscope device - Google Patents

Abstract

PURPOSE:To project the linear pattern light and to execute the shape measurement with high accuracy by providing a pattern projection member so that a laser beam after polarization is made incident vertically against the pattern projection member. CONSTITUTION:A laser beam led by an optical fiber 6 is focused and polarized, and thereafter, allowed to pass through a pattern projection member 10 and a pattern projection light is generated, and by projecting the pattern projection light to an object 2 to be photographed and detecting an obtained reflected light by an image pickup element, a shape of the object 2 to be photographed is measured. In this case, the pattern projection member 10 is provided so that a laser beam after polarization is made incident vertically against the pattern projection member 10. In such a way, a pattern light projected to the object 2 to be photographed becomes linear, and the shape measurement can be executed with high accuracy.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention projects pattern projection light onto a subject from the tip of an endoscope scope, detects this reflected light with an image sensor, and detects the subject. The present invention relates to a shape measuring endoscope device that measures the shape of.

(Prior art) Shape measuring endoscope devices, which have been actively developed in recent years, emit a laser light pattern onto a subject from the tip of an endoscope scope, and detect this reflected light with an image sensor. The shape of the subject is measured.

FIG. 7 is a diagram for explaining the operating principle of the shape measuring endoscope, in which a line is provided in the forceps channel 12 at the tip of the endoscope 1 in a direction perpendicular to the paper surface of the subject 2. A pattern projection system 4 for projecting the shaped pattern light 3 and an observation section 5 for observing the pattern light 3 projected onto the subject 2 are mounted.

Now, as shown in the figure, the longitudinal direction of the endoscope 1 is determined as the Z coordinate, the width direction as the X coordinate, and the direction perpendicular to the plane of the paper as the Y coordinate. Then, the irradiation angle of the pattern light 3 irradiated from the pattern projection system 4 is θα.

X of any point P on the patterned light 3 observed by the observation unit 5
The angle in the axial direction is θ, the angle in the Y-axis direction is θPYs The parallax (distance between the irradiation position of pattern light 3 and the observation position) is Pa
The coordinates (Xp, Yp,
Zp) is based on the principle of triangulation as follows (1) ~
It is shown by equation (3).

ZP −P s / (1*n θα+[■θPri
−(+)X p = Z p ・1■θpx
'...(2) Y, WZP Tsukuda xnθPY
-(3) The spatial coordinates of each point on the pattern light 3 can be determined, and the shape of the subject can be measured based on this.

Figure 8 shows a detailed configuration diagram of the tip of the conventional Nokuturn projection system 4, in which the laser beam guided by the optical fin (6) is focused by the focusing lens 7, and then the light amount is controlled by the aperture 8. The beam is deflected by the deflection prism 9. Then, by passing through the diffraction grating 10, pattern light is generated and
projected on.

At this time, the curved light emitted from the diffraction grating 10 must be projected in a straight line.

However, as is clear from FIG. 8, since the laser beam polarized by the deflection prism 9 is incident on the diffraction grating 10 from an oblique direction, the patterned light 3 does not form a straight line but a distorted curve. turn into.

On the other hand, as shown in FIG. 7, this type of endoscope 1 is equipped with forceps for the purpose of inserting various members for performing operations such as spraying cleaning water onto the subject 2 and cutting out the subject. A channel 12 is provided. The pattern projection system shown in FIG. 8 is normally inserted into this forceps channel 12 for use.

At this time, in order to fix the irradiation angle θα of the patterned light 3 shown in FIG. 7, the pattern projection system 4 shown in FIG.
It is covered by a torque cable 11 that can transmit the rotational force applied from the operation side to the distal end of the scope with almost no loss.

However, in the conventional device, no measures were taken to fix the torque cable 11 on the operating side.
It was difficult to maintain the irradiation angle θα at a constant value.

(Problems to be Solved by the Invention) As described above, in the conventional shape measuring endoscope device, since the laser beam is incident from an oblique direction on the diffraction grating 10 provided at the tip of the pattern projection system 4, There was a drawback that the light 3 was distorted.

Furthermore, a torque cable 1 in which a pattern projection system 4 is installed is also provided.
1 cannot be easily fixed on the operating side, the pattern projection system 4 may rotate during shape measurement.
As a result, there was a problem in that the irradiation angle θα of the patterned light 4 fluctuated, making it impossible to measure the shape with high precision.

This invention was made to solve these conventional problems, and its purpose is to be able to irradiate a linear pattern of light without distortion, and to securely connect the torque cable to the operating side. An object of the present invention is to provide a shape measuring endoscope device that can be fixed to a shape measuring device.

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, the present invention, in claim 1, focuses a laser beam guided by an optical fiber.

A shape measurement endoscope that generates pattern projection light by passing through a pattern projection member after polarization, projects the pattern projection light onto a subject, detects the resulting reflected light with an image sensor, and measures the shape of the subject. The apparatus is characterized in that the pattern projection member is disposed such that the polarized laser light is incident on the pattern projection member at right angles.

Further, in claim 2, the pattern projection member has a planar shape that is orthogonal to a plane normal to the optical axis of the incident laser light, and an angle formed by one of the adjacent sides is an obtuse angle, and the adjacent side has an obtuse angle. It is characterized by being a columnar body formed in the shape of a parallelogram with an obtuse angle with the other side.

Furthermore, according to a third aspect of the present invention, there is provided a shape measuring endoscope apparatus that projects pattern projection light onto a subject from a distal end of an endoscope scope, and detects the reflected light with an image sensor to measure the shape of the subject. A keyway is formed in the operation side end of a forceps channel provided in a mirror scope, and the pattern projection light irradiation means is a tube capable of transmitting rotational force applied from the operation side to the distal end of the scope with almost no loss. A feature of the present invention is that a key is formed at the operation side end of the tube cylinder to be inserted into the cylinder and to fit into the key groove.

(If configured as described above, the laser light will be incident on the pattern projection member such as the diffraction grating at right angles. As a result, the pattern light projected onto the subject will be linear, resulting in high accuracy. shape measurement becomes possible.

Furthermore, if the side surface shape of the pattern projection member is formed to be a parallelogram, it will fit better in the pattern projection system and can be easily disposed.

Further, a keyway is formed in a forceps channel provided within the endoscope, and a key that fits into the keyway is formed at the operation side end of the tube tube disposed within the forceps channel. Therefore, by fitting this key with the keyway, the rotational position of the tube can be fixed, thereby irradiating the pattern light emitted from the pattern projection light irradiation means provided inside the tube. The angle can be kept constant.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 4 is an external view of the shape measuring endoscope device in this embodiment.

The shape measuring endoscope device shown in the figure includes an endoscope scope 1, a main body 24 including a processor 20 that processes image data captured by the scope 1, and a monitor 21 that displays the processed image data. The endoscope 1 is connected to a main body 24 via an operating section 22° and a universal cord 23.

The main body 24 also includes an illumination light source 25, illumination from this light source,
It has a rotary filter 26 that switches the light shielding, and the light source 2
The light emitted from the endoscope 1 is guided to the distal end of the endoscope 1 via a light guide (not shown), and irradiates the subject 2 with an amount of light that can be imaged.

The laser light source 27 emits a laser beam for projecting pattern light 3 onto the subject 2, and this laser beam is transmitted to the tip of the endoscope 1 via an optical fiber of a pattern projection system, which will be described later. It is meant to be guided.

FIG. 1 is a block diagram of the tip of a pattern projection system 4, which is the main part of the present invention. The pattern projection system 4 is disposed within a forceps channel (not shown) provided in the endoscope 1 shown in FIG. A fiber 6, a focusing lens 7 that focuses the guided laser light, an aperture 8 that adjusts the amount of laser light, a polarization prism 9 that polarizes the laser light, and a line-shaped pattern light that is generated from the laser light. It has a diffraction grating 10 that illuminates the subject 2.

Here, in the present invention, as a result of intensive study by the inventors,
It has been experimentally confirmed that when the laser light that has passed through the deflection prism 9 is incident on the diffraction grating 10 at right angles, the pattern light projected onto the subject 2 becomes linear.

Therefore, in this embodiment, the diffraction grating 10 is connected to the pattern projection system 4.
It is installed at a slight incline with respect to the longitudinal direction of the laser beam, so that the laser beam is incident at right angles. As a result, a linear pattern of light 3 is projected onto the subject 2, allowing highly accurate shape measurement.

Furthermore, arranging the diffraction grating in the pattern projection member 4 in an inclined manner is very difficult to fit and lacks stability. Therefore, when the diffraction grating 10 is tilted as shown in FIG. 2(A), the upper end surface 10a1 and the lower end surface 10b are formed so as to be parallel to the longitudinal direction of the pattern projection system 4. That is, the diffraction grating is processed and formed so that the cross-sectional shape of the side surface is a parallelogram (excluding rectangles). As a result, as shown in FIG. 3, the diffraction grating 10 can be easily accommodated within the pattern projection system 4, improving stability.

In addition, as a pattern projection member other than the diffraction grating 10, a rod lens 30 shown in FIG. 2(B) and a rod lens 30 shown in FIG. 2(C) are used.
Similarly, when the cylindrical lens 31 shown in FIG.

FIG. 5 is an overall configuration diagram of the pattern projection system 4. As shown in FIG.

As shown in the figure, the torque cable 11 is connected to an adjustment section 41, and by rotating the adjustment section 41, the irradiation angle of the patterned light 3 emitted from the tip section 43 can be adjusted. .

The adjustment unit 41 is connected to a connector 40 via a tube 42 that has an optical fiber for guiding the laser beam, and the connector 40 is fitted to the laser light source 27 shown in FIG. 4 to transmit the laser beam. It leads to optical fiber.

Further, the adjustment section 41 is provided with a key 44, the cross-sectional shape of which is configured as shown in FIG. 6(A).

On the other hand, as shown in FIG. 6(B), the torque cable 11
The insertion part of the forceps channel 12 into which the forceps are inserted is provided with the key 4.
A keyway 45 is formed to fit into the keyway 4. And key 4
If the irradiation angle of the pattern light 3 emitted from the pattern projection system 4 is set in advance to be a predetermined value when the pattern projection system 4 and the keyway 45 are fitted together, the operator can easily rotate the pattern projection system. You can adjust the position.

In this manner, in this embodiment, the diffraction grating 10 provided in the pattern projection system 4 is arranged so that the laser beam is incident at right angles. Therefore, the pattern light projected onto the subject 2 becomes linear, allowing highly accurate shape measurement.

Furthermore, if the diffraction grating 10 is arranged so that its upper end face and lower end face are parallel to the longitudinal direction of the pattern projection system 4, the pattern projection system 4 of the diffraction grating 10 can be It fits better and improves stability.

Furthermore, in this embodiment, a key 44 is formed in the adjustment section 41 of the pattern projection system 4, and a key groove 45 that fits this key 44 is formed in the insertion opening of the forceps channel 12. The rotational position of the torque cable 11 can be easily determined simply by fitting the keyway 45, and thereby the irradiation angle of the patterned light 3 can be kept constant.

[Effects of the Invention] As explained above, in the present invention, a pattern projection member such as a diffraction grating is arranged so that a laser beam is incident at right angles. Therefore, it is possible to project linear pattern light without distorting the pattern light as in the conventional case, and as a result, highly accurate shape measurement is possible.

Furthermore, if the upper and lower end surfaces of the pattern projection member are processed to form a side surface shape of a parallelogram, the pattern projection member can be better fitted into the pattern projection system and stability can be improved.

Furthermore, a keyway is formed at the operation side end of the forceps channel,
Since a key that fits into the key groove is formed on the operation side of the tube tube in which the pattern projection system is installed, the rotational position of the pattern projection light irradiation means can be easily determined, and the irradiation angle of the pattern light can be adjusted. This has the effect of being able to fix the value to a constant value.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a pattern projection system in a shape measuring endoscope to which the present invention is applied. FIG. 2 is an explanatory diagram showing the shape of each pattern projection member. FIG. 3 is a configuration diagram showing a modification of the pattern projection system. Figure 4 is an external view of the shape measurement endoscope, Figure 5 is an overall configuration diagram of the pattern projection system, Figure 6 is an explanatory diagram showing the cross-sectional shape of the adjustment section and forceps channel, and Figure 7 is the inside of the shape measurement endoscope. FIG. 8, which is an explanatory diagram showing the measurement principle of the endoscope, is a configuration diagram of a conventional pattern projection system. 1... Endoscope scope 3... Pattern light 4...
Pattern projection system 10... Diffraction grating 11... Torque cable 12... Forceps channel 27... Laser light source 30... Rod lens 31... Cylindrical lens 41... Adjustment section 44... Key 45...Keyway ■L Patent Attorney Hidetoshi Miyoshi Figure 3 (A) Figure 4 Figure 5 CB) Figure $1

Claims (3)

[Claims] (1) Laser light guided by an optical fiber is focused, polarized, and then passed through a pattern projection member to generate pattern projection light;
In a shape measuring endoscope device that measures the shape of a subject by projecting the pattern projection light onto a subject and detecting the reflected light obtained by using an image sensor, polarized laser light is directed to the pattern projection member. A shape measuring endoscope device characterized in that the pattern projection member is arranged so that the pattern projection member is incident at a right angle. (2) The pattern projection member has a planar shape that is perpendicular to a plane normal to the optical axis of the incident laser beam, and the angle between the adjacent side and the other side is obtuse. The shape measuring endoscope device according to claim 1, wherein the shape measuring endoscope device is a columnar body formed in the shape of a parallelogram having obtuse angles. (3) In a shape measuring endoscope device that projects pattern projection light onto a subject from the tip of an endoscope scope and measures the shape of the subject by detecting this reflected light with an image sensor, A key groove is formed at the operation side end of the provided forceps channel, and the pattern projection light irradiation means is inserted into a tube tube that can transmit the rotational force applied from the operation side to the distal end of the scope with almost no loss. A shape measuring endoscope device, further comprising: a key that fits in the key groove formed at the operation side end of the tube tube.