JPH07281105A - Endoscope device - Google Patents

Abstract

PURPOSE:To provide an endoscope device which can measure the depth of the wound of an object or the like from an oblique direction by an optical cutting method using a endoscope. CONSTITUTION:By projecting a laser line from the laser line projection part of the electronic endoscope so as to pass through the recessed part of the inner surface of a pipe caused by corrosion and instructing designated points (a) and (b) for regulating a straight line being the reference of measurement set at laser line image parts p2 and p3 without irregularities on the inside surface of the pipe on the image and the designated point (c) of the measurement for measuring the depth of a recessed part image 45' from a keyboard, the straight line passing through the points (a) and (b) being the reference is calculated by a CPU. Besides, an actual value K corresponding to a distance (k) obtained when a perpendicular is drawn to the straight line from the point (c) is obtained and the depth of the recessed part is calculated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention projects a line on an object, obtains an approximate expression for a reference line portion on the line, and obtains the distance from the three-dimensional position of the concave portion or the convex portion to the approximate expression to determine the concave portion. The present invention relates to an endoscope device provided with a length measuring function for measuring a depth or a height of a convex portion.

[0002]

2. Description of the Related Art In recent years, it has been possible to observe an internal organ in a body cavity by inserting an elongated insertion portion into the body cavity and to perform various medical treatments by using a treatment instrument inserted into a treatment instrument channel as needed. Endoscopes are widely used. Also in the industrial field, industrial endoscopes are widely used for observing and inspecting internal scratches and corrosion of boilers, turbines, engines, chemical plants and the like.

US Pat. No. 4,980,763 discloses a means for measuring the shape of an object by a light section method, in which a linear contrast light is emitted from an illumination light source at the tip of an endoscope. Japanese Unexamined Patent Publication (Kokai) No. 51-95866 discloses a means for observing the direction of irregularities on the inner surface of a pipe by using a light cutting method.

Japanese Patent Publication No. 2-43487 discloses a means for measuring the distance to an object by projecting a beam of light from the tip of an endoscope onto the object plane. US Patent 4,98
In the light cutting method shown in No. 0,763, it is possible to measure the length on the line, the shape of the object that changes smoothly without interruption of the line, and the step difference where the correspondence of the interrupted line is clear.

[0005]

However, only the measuring method in the case where the object plane is perpendicular to the axis of the endoscope is shown, and for example, when the inner surface of the pipe is observed obliquely with the endoscope. The method of measuring the depth of is not shown. However, in general, when observing the inner surface of the pipe with a measuring endoscope, the relative accuracy between the inner surface of the pipe and the tip of the endoscope is not known, and therefore the measurement accuracy cannot be guaranteed by the method according to the prior art.

Japanese Unexamined Patent Publication (Kokai) No. 51-95866 discloses means for observing the direction of irregularities on the inner surface of a pipe by using the light cutting method. However, with this technique, the inner surface of the pipe must be observed vertically, and no method for measuring the depth is shown.

Japanese Patent Publication No. 2-43487 discloses means for projecting a beam of light from the tip of an endoscope onto an object surface to measure the distance to the object. The method for measuring the depth of the object surface is as follows. Nothing is shown.

It is an object of the present invention to provide an endoscope apparatus capable of accurately measuring the depth of the inner surface of a pipe by observing it from an oblique direction by a light cutting method using an endoscope.

Another object of the present invention is to provide an endoscope apparatus capable of easily measuring a concave portion or a convex portion.

[0010]

Means and Actions for Solving the Problems An elongated insertion portion, an illumination optical system which is provided on the tip side of the insertion portion and emits illumination light to an object, and an object illuminated by the illumination light. An objective optical system for forming an image, a reference line projecting means for projecting a reference line passing through a concave portion or a convex portion to be measured existing on the surface of the object, and an image pickup device for photoelectrically converting the image based on the objective optical system. An endoscope including: a signal processing unit that performs a signal process on the image sensor to generate a video signal; and corresponds to the object on which the reference line is superimposed by inputting the video signal. Display means for displaying an image; a position designating means for designating an arbitrary position of the image; a reference line passing through the surface is regarded as a reference line for measurement, and the reference line is three-dimensional. Calculation of the approximate line expression, calculation of the three-dimensional coordinate position corresponding to the point designated by the position designating means on the reference line passing through the concave portion or the convex portion, the approximate line and the three-dimensional coordinate Calculating means for calculating the distance of the position to calculate the depth of the concave portion or the height of the convex portion; and the concave portion or convex portion with respect to an approximate line serving as a reference line with respect to a reference line passing through the surface. The depth etc. can be easily measured by obtaining the distance from the specified point on the reference line passing through the section.

[0011]

Embodiments of the present invention will be specifically described below with reference to the drawings. 1 to 15 relate to a first embodiment of the present invention, FIG. 1 is an external view showing the overall configuration of the endoscope apparatus of the first embodiment, FIG. 2 is an overall configuration diagram of the endoscope apparatus, and FIG. 4A is a cross-sectional view showing the structure of the endoscope tip portion, and FIG. 4A is a plan cross-sectional view of a laser line projection portion provided at the endoscope tip portion.
4B is a side sectional view of the laser line projection portion, FIG.
Shows a structure of a plane parallel plate used in a laser line projection unit, FIG. 5 (A) is a sectional view of a laser line light source having a fine movement mechanism of a die, and FIG. 5 (B) is FIG. 5 (A). 5 is a cross-sectional view taken along the line AA of FIG. 5, FIG. 5C is a cross-sectional view showing a fine movement mechanism of the die in the preceding example for comparison, and FIG. 5D is FIG. 5C.
6 is a cross-sectional view taken along line EE in FIG. 6, FIG. 6 is a block diagram showing a schematic configuration of an electric system of the endoscope apparatus, FIG. 7 is a view in which a laser line is projected on an object plane parallel to the tip end surface, and FIG. 9 is an explanatory view of the relationship between the measurement point and the optical system at the BB cross section position, FIG. 9 is an explanatory view showing a state in which a laser line is projected on an oblique object plane on the tip surface, and FIG. 10 is a side view of FIG. FIG. 11 is an explanatory view showing the imaged image in FIG. 9, FIGS. 12 (A) and 12 (B) are explanatory views showing the relationship between the measurement points and the optical system, and FIG. 13 is a laser line projected on the inner surface of the pipe having a recess. FIG. 14 is an explanatory diagram showing a captured image corresponding to FIG. 13, and FIG. 15 is a flowchart showing processing contents for calculating the depth of the recess.

As shown in FIGS. 1 and 2, the endoscope apparatus 1 of the first embodiment has an electronic endoscope 2 having a built-in image pickup means and the electronic endoscope 2 is connected to the electronic endoscope 2. A light source 3 for supplying illumination light to the light source 2, a measuring unit 4 having a function of performing signal processing for the image pickup means of the electronic endoscope 2 and measuring the length, the electronic endoscope 2 and the light source for illumination. 3 and a laser light source 5 for generating a laser beam.

The electronic endoscope 2 has a slender insertion portion 6 having flexibility, an operation portion 7 provided at the rear end of the insertion portion 6 to be gripped, and a universal portion extended from the operation portion 7. Cord 8 and the end of the universal cord 8 is connected to the laser light source 5. An electric cable 9 is extended from the laser light source 5 and connected to the measuring unit 4 having a signal processing system for measuring the length.

The insertion portion 6 has a hard tip portion 11 and a bendable bending portion 12 adjacent to the tip portion 11,
The bending portion 12 can be bent by rotating the bending operation knob 13 provided on the operation portion 7.

A light guide 10 for transmitting illumination light is inserted into the insertion portion 6 and the universal cord 8, and the illumination light supplied from the lamp 3a in the illumination light source 3 through the lens 3b to the end face is transmitted, Two illumination windows 1 at the tip 11
The transmitted illumination light is emitted forward through the illumination lens 14a attached to each of Nos. 4 and 14 (only one is shown in FIG. 2) to illuminate the front object plane 15.

An observation window 16 is provided adjacent to the illumination windows 14, 14, and an objective lens system 17 is attached to the observation window 16 as shown in FIG. A charge-coupled device (abbreviated as CCD) 18, for example, is arranged as a solid-state image sensor on the focal plane of the objective lens system 17, and forms an optical image of an illuminated object plane 15 on the CCD 18. This CC
For example, a mosaic filter 18b is provided on the photoelectric conversion surface of D18.
Is attached, and color separation is optically performed for each pixel.

An image pickup section (or image pickup system) 19 for obtaining a picked up image is formed by the objective lens system 17 and the CCD 18. The electronic endoscope 2 is a direct-viewing type endoscope having an observation visual field in a direction parallel to the axis of the insertion portion.

The leads projecting from the back surface of the CCD 18 for converting the optical image formed by the objective lens system 17 into an electric signal are connected to a flexible substrate 20, and the flexible substrate 20 is bent and a signal is output to the rear end side extending rearward. The tip end of the cable 21 is connected, the signal cable 21 is inserted through the universal cord 8 from the operation portion 7, and the rear end is connected to the measuring unit 4 via the electric cable 9.

Further, as shown in FIG. 3, a laser line projection unit 22 is attached to a window portion formed adjacent to the observation window 16. Then, the laser light generated by the laser diode 56 in the laser light source 5 is transmitted through the optical fiber 23, and the transmitted laser light is transmitted through the laser line projection lens system 24 to the front object plane 15 (FIG. 1 or FIG. See 7.
In FIG. 2, the state of projection on the inner surface 44 of the pipe is shown), and a linear laser beam is projected on the side to form a laser line 41 on the object plane 15. The laser line 41 formed by projection on the object plane 15 is used to measure the depth and the like (measurement by the optical cutting method).

FIG. 4A is an enlarged view of the laser line projection unit 22 shown in FIG. In addition, FIG.
The cross section seen from the side of (A) is shown. FIG. 4C shows FIG.
The detailed view of the plane parallel plate 24c used for (A) and 4 (B) is shown. The optical fiber 23 is composed of, for example, a core portion 23a having a high refractive index, a clad portion 23b having a refractive index smaller than that of the core portion 23a, and a jacket portion 23c for protecting them, and the laser light is provided with the core portion 23a and the clad portion 23b. The core portion 23 while being totally reflected at the boundary surface of
a.

The emitted light emitted from the front end surface of the optical fiber 23 held by the base 25 is the lenses 24a, 2
After being made into a desired light flux by 4b, it passes through the plane-parallel plate 24c and is incident on the cylindrical lens 24d having the convex surface 51 as shown in FIG. 4B. A light beam emitted from the cylindrical lens 24d becomes a light beam having a fan shape as shown in FIG. 4B, and is emitted forward through the cover glass 24e.

As shown in FIG. 4C, a slit diaphragm 26 is formed on the parallel plane plate 24c by vapor deposition or the like (in FIG. 4C, a slit-shaped opening through which light is transmitted vertically is formed. A light-shielding film is formed in the shaded area so that
In FIG. 4A, the slit-shaped openings are arranged so that the longitudinal direction thereof is the direction perpendicular to the paper surface).

The parallel plane plate 24c is adhered to the lens frame 27a, and the cylindrical lens 24d is attached to the lens frame 27.
glued to b. The lens frame 27a and the lens frame 27b are adhered and fixed such that the longitudinal direction of the opening of the slit diaphragm 26 of the plane parallel plate 24c coincides with the light spreading direction of the cylindrical lens 24d.

As described above, by providing the slit diaphragm 26, the line width can be narrowed as shown in FIG. 4A without narrowing the spreading direction of the laser beam shown in FIG. 4B.
That is, as shown in FIG. 4A, only the laser light incident on the plane parallel plate 24c at a small angle with the optical axis passes through the opening of the slit diaphragm 26, and the laser light incident at a large angle is shielded. Line width can be reduced. On the other hand, FIG.
As shown in (B), since no light is shielded in the longitudinal direction of the slit-shaped opening, the line length of the laser line projected on the object can be increased.

The slit width is preferably about 0.2 mm. If the slit width is made wider than this, the line width becomes thicker and the measurement resolution is reduced. On the contrary, even if the width is made narrower than this, the line width becomes thick due to the influence of diffraction, and the measurement resolution also deteriorates.

Further, the position where the plane parallel plate 24c provided with the slit diaphragm 26 is arranged should be set away from the pupil position 28 as shown in FIG. 4 (A). Pupil position 2
This is because the diaphragm effect disappears near 8.

The convex surface 51 of the cylindrical lens 24d is arranged so as to be on the optical fiber 23 side. As a result, the amount of spherical aberration generated can be reduced and the spread of light rays can be increased. That is, there is an effect that the intensity of the laser line projected on the object plane 15 is made uniform and the length of the laser line can be projected long.

The optical fiber 23 is preferably a single mode fiber. When a multimode fiber is used, the efficiency of incidence of the laser on the fiber is improved, but a plurality of modes exist in the transmission of light, and the plurality of modes interfere with each other to cause intensity unevenness in the light emitted from the fiber. Therefore, there is a drawback in that the intensity of the light projected on the object plane 15 is uneven.

FIGS. 5A and 5B show a cross section including the y axis and a cross axis including the x axis of the laser light source unit 53 in the laser light source 5. The laser light source unit 53 includes a light emitting portion 54 and a light receiving portion 55 having a moving mechanism for the light emitting portion 54. The light emitting unit 54 is composed of a laser die 56, a collimator lens 57 for making the light into parallel rays, and a condenser lens 58 for condensing the light on the end face of the fiber.

The light receiving section 55 comprises a main body 59, a base 61 of the optical fiber 23, and a base receiver 62. The main body 59 receives pressure on the frame 64 of the light emitting unit 54 in the z direction by the thrust pressing spring 65. The reaction force is received by the z direction fine adjustment screw 66, and the main body 59 moves in the z direction by rotating the z direction fine adjustment screw 66.

By this adjustment, the light of the condenser lens 58 is condensed on the end face of the fiber. Further, the cap receiver 62 includes y direction fine adjustment screws 68a and 68b and x direction fine adjustment screws 69a and 69b.
The fiber end face is movable in a direction (x, y) perpendicular to the optical axis. Also, the base 6
2 is supported by the O-ring 70, and the fine movement screw 68a68
While acting as a pressing spring for b, 69a and 69b,
It prevents dust from entering the space 72.

Further, in the present embodiment shown in FIGS. 5A and 5B, the main body 59 is provided with pressing springs 73a and 73b for pressing the frame 64 of the light emitting portion 54 from the radial direction, and mechanical springs are provided. The backlash is removed. Pressing springs 73a, 73b
A cap 74 is put on the outside of the. Generally, the core diameter of an optical fiber is several μ to several tens μ, and the attachment of dust to this end face causes a fatal loss of light quantity. By using the O-ring 70 as the pressing member for the fine movement screw as in the present embodiment, it is possible to provide a dustproof effect that prevents dust from adhering to the end face of the fiber with a compact and inexpensive structure.

For comparison, FIG. 5C and FIG.
A preceding example of a y-direction fine movement mechanism is shown. FIG. 5D is FIG.
The EE cross section of (C) is shown. The base 201 is pressed by a pressing member, for example, plungers 204, 205 pressed by pressing springs 202, 203. Fine adjustment screws 206a, 2 are provided at positions facing the plungers 204, 205.
06b is provided so that the base 201 can be finely moved in the x and y directions. In this structure, a gap is formed between the base 201 and the frame 208, which causes a problem that dust adheres to the end surface of the fiber 209. Further, since the pressing mechanism is required, the structure becomes large and the cost becomes high.

On the other hand, in the present embodiment shown in FIGS. 5A and 5B, the O-ring 70 is used as the pressing member for the fine movement screw, and the intrusion of dust is prevented with a compact and inexpensive structure. Instead of the laser diode 56 shown in this embodiment, an LED (which emits light such as red light, or emits light having a wavelength of 600 to 700 nanometers) may be used, and a small structure which emits red light is used. It may be a light emitting body such as a light bulb.

FIG. 6 shows a schematic configuration of a signal processing system of the endoscope apparatus 1. The CCD 18 built in the electronic endoscope 2 is driven by a CCD drive signal from a CCD drive circuit 35a in a camera control unit (hereinafter abbreviated as CCU) 35, and an image pickup signal output from the CCD 18 is in the CCU 35 by this drive signal. Signal processing is performed by the process circuit 35b to generate an image signal including, for example, R, G, B color signal components.

This video signal is converted into digital image data by the A / D converter 35c and written in the frame memory 36a. The frame memory 36a is written by the memory controller 31 to write / read image data.
Leads are controlled. The image data read from the frame memory 36a is converted into an analog image signal by a D / A converter 35f via an adder 35e, and further, for example, an encoder 35g adds a synchronization signal SYNC or the like to a standard color video signal. The converted image is output to the CRT 37 as an image display unit, and the endoscopic image captured by the image capturing unit 19 is displayed on the display surface of the CRT 37.

In addition, the measuring unit 4 has a cursor generating circuit 32 using a character generator or the like,
The cross-shaped cursor (for example, + or X or *) generated by the cursor generating circuit 32 can be written in an arbitrary position in the frame memory 36b via the CPU 38 by operating the keyboard 40.

The frame memory 36b is composed of a semiconductor memory having the same structure as the frame memory 36a. The cursor written in the frame memory 36b is read out together with the picked-up image written in the other frame memory 36a and added. The value is added by the device 35e and is superimposed and displayed on the display surface of the CRT 37.

Therefore, it has a cursor display function for displaying the cursor on the display surface. Writing and reading of this cursor are controlled by the CPU 38 via the memory controller 31. When performing the length measurement, the CPU 38 refers to the position of the cursor written in the frame memory 36, and calculates the coordinate value of the designated point designated on the image.

That is, the frame memories 36a and 36b are the frame memories 36a for storing images. The frame memory 36a has the same structure as that of the frame memories 36a, and the frame memory 36b stores the cursors. Both of these memories generate the same address signal. It is accessed by the address signal from the circuit 31a. For example, during normal reading, the storage data of both frame memories 36a and 36b are sequentially read by the same address signal, and therefore both storage data read by the memory cells of the same address are displayed at the same position on the CRT 37. become.

When the cursor 40 is moved from the keyboard 40, for example, the cursor moves on the frame memory 36b under the control of the CPU 38.
The cursor displayed on the display surface of the CRT 37 also moves. Therefore, the coordinates of the point on the image designated by the cursor on the display surface of the CRT 37 correspond to the address on the frame memory 36b, and the coordinate position of the cursor is identified or determined by this address. Then, in the case of length measurement, the CPU 38 calculates the coordinate position by moving the cursor to an arbitrary position on the image and reading the address.

Further, each frame memory can be independently written, read or erased by a select signal or the like for selecting each frame memory. Therefore, it has a cursor display function for displaying the cursor on the display surface and a function for reading out the coordinates of the cursor on the frame memory 36b.

Further, with respect to the image displayed on the CRT 37, the CPU 38 calculates the three-dimensional coordinates of the position-specified point by specifying the position with a cursor and the like, and the measurement calculation for calculating the depth of the concave portion described later. Process. That is, the CPU 38 has a processing function of a measurement calculation unit (or length measurement calculation unit) 38a that calculates the depth of the concave portion or the height of the convex portion.

More specifically, the function of the measurement calculation section 38a is to calculate a line calculation section 38b for calculating a three-dimensional mathematical expression of a reference line and three-dimensional coordinates of a measurement instruction point designated for measurement in a recess. It is composed of a three-dimensional coordinate calculation unit 38c and a length calculation unit 38d that calculates the length of the perpendicular line drawn from the measurement instruction point to the reference line.

When the CPU 38 performs the processing of the measurement calculation section 38a, for example, the data (H) necessary for the calculation recorded on the floppy disk of the floppy disk drive 34 is used.
Value, etc.), temporarily store the data in the data storage area of the RAM 33, refer to the data,
Performs calculations for length measurement such as depth or height. Further, a part of the RAM 33 is used as a work area for calculation.
Floppy disk drive 3
It is possible to record on 4 floppy disks.

In this embodiment, the laser diode 56, which is the light source of the laser line, has a wavelength of, for example, 600 to 70.
By using a laser beam of 0 nm, the laser line projected on the object plane can be distinguished from the object plane with good contrast. If the wavelength is longer than 700 nanometers, the infrared cut filter normally used in the image pickup optical system of the endoscope attenuates the light, making it impossible to take an image.
If the infrared cut filter is arranged on the side of the light source for illumination or on the side of the optical system that emits illumination light inside the endoscope, a laser diode that emits laser light with a wavelength longer than 700 nanometers is used. Can be used.

By setting the thickness to 600 nm or more, the emission intensity of the laser diode 56 can be controlled from the red signal intensity as follows. The CPU 38 reads the red signal strength from the frame memory 36a,
An instruction is issued to the laser diode drive circuit 39 so that the CCD 18 does not reach a saturation level, and the light amount or emission intensity of the laser light is controlled.

Generally, the inner surface of the pipe, which is the main object to be measured in this embodiment, is soiled with rust, deposits, etc. and has a low reflectance, but the red light can be recognized with a relatively good contrast. Further, since a red semiconductor laser that emits red laser light has a high optical output and is available at a low price, the system or the endoscope apparatus 1 can be used by using the red semiconductor laser.
Can lower the price of.

When the CPU 38 inputs a measurement instruction from the keyboard 40, the CPU 38 performs a length measurement (length measurement) calculation process described later. 7 and 8 show the principle of measurement. As shown in FIG. 7, the fan-shaped light emitted from the laser line projection unit 22 draws a laser line 41 on the object plane 15. FIG. 8 shows a BB cross section of FIG. 7. The dotted line in FIG. 8 indicates the visual field range.

The entrance pupil position of the objective lens system 17 is O, the exit position of the laser line projection unit 22 is R, a point on the laser line 41 projected on the object plane 15 and a point in the BB cross section. Let P. Also, the optical axis 17a of the objective lens system 17
And the angle between O and P is θ. Laser line emission position R
If the distance RP from the object plane to the object surface is L, this L is O
It is calculated by the product of the distance H of −R and tan (90−θ), that is, L = H × tan (90−θ) (1). In FIG. 8, the point P is imaged at the point p on the imaging surface 18a of the CCD 18.

FIG. 9 shows a state in which the laser line 41 is projected on the oblique plane Π. FIG. 10 shows a side view thereof. Figure 1
Reference numeral 1 denotes an image obtained by imaging the measurement points P0 and P1 on the laser line 41 in FIG. 9 or 10, for example, on the frame memory 36a (or 36b). In addition, FIG.
12 (A) and 12 (B) are explanatory views for obtaining a relational expression for length measurement when the measurement points P0 and P1 are imaged by using the imaging optical system (the objective lens system 17 in this embodiment). .

A coordinate system is set in which the entrance pupil position on the central axis (optical axis) of the image pickup optical system is the origin O of the three-dimensional coordinates. Also, for the sake of clarity, the Z axis of the three-dimensional coordinate is set in the optical axis direction, and the two-dimensional coordinate plane is moved on this optical axis and placed on the measurement point side (that is, the plane including the measurement point P0 or P1). Done 2
The dimensional coordinates are (X, Y), and the imaging side (that is, the imaging surface 18a
Alternatively, the two-dimensional coordinates arranged on the frame memory 36) are indicated by (x, y).

In this case, the origin Op on the measurement point side is Z0 (in the case of point P0) or Z1 on the optical axis from the origin O of the three-dimensional coordinates.
At the moved position (in the case of point P1), the origin om on the imaging side is the focal length f of the objective lens system 17 from the origin O of the three-dimensional coordinates.
It exists at the moved position, and the x-axis and the X-axis and the y-axis and the Y-axis are both parallel. Further, in this embodiment, the x or X coordinate is set in the direction connecting the emission position R and the origin O.

The image of the image pickup surface 18a of the CCD 18 is stored in the frame memory 36a as it is (for example, the center of the image pickup surface 18a is set to be the center of the frame memory 36a, and the position designated by the same coordinates is set). If the units or scales differ from each other, they can be converted into corresponding points by multiplying one by a coefficient, etc.). Therefore, when the measurement points P0 and P1 on the laser line 41 are imaged,
Corresponding points on the frame memory 36 are p0 and p1.

Further, as shown in FIG.
The coordinates of 0 and P1 are (X0, Y0) and (X1, Y1), respectively.
), The frame memory 36 as shown in FIG.
The coordinates of the corresponding points p0 and p1 on a are (x0, y0
), (X1, y1). In addition, since the x-axis or the X-axis is set in the direction connecting the emission position R and the origin O, FIG.
In (A), the length of Op-X0 and Op-X1 is H.

On the frame memory 36a, the angle formed by the line connecting the origin om and the measuring point (image of P0) p0 and the x-axis is α0,
The angle formed by the line connecting the origin om and the measurement point (image of P1) p1 and the x-axis is α1. The maximum angle of view of the image is θg, and the coordinates on the frame memory 36a are (xg, yg).

When the image pickup optical system has a SIN θ type distortion, the following equations are used to obtain the values shown in FIGS.
The angles θ0 ′, θ1 ′, θ0, θ1 shown in (B) are obtained.

Θ0 ′ = sin ⁻¹ {x0 × sin (θg) / sqr (xg ² + yg ² )}, θ1 ′ = sin ⁻¹ {x1 × sin (θg) / sqr (xg ² + yg ² )} (2 ) θ0 = sin ⁻¹ {sqr (x0 ² + y0 ² ) × sin (θg) / sqr (xg ² + yg ² )}, θ1 = sin ⁻¹ {sqr (x1 ² + y1 ² ) × sin (θg) / sqr ( xg ² + yg ² )} (2 ′) Here, for example, sqr (x0 ² + y0 ² ) represents the square root of (x0 ² + y0 ² ).

The distances L0 and L1 to the planes containing the measurement points P0 and P1 are L0 = H.times.tan (90-.theta.0 ') and L1 = H.times.tan (90-.theta.1') (3), respectively.

Further, the distance s0 between Op-P0 and Op-P
The distances s1 between 1 are s0 = L0 * tan ([theta] 0) and s1 = L1 * tan ([theta] 1) (4), respectively.

The angles α0 and α1 are obtained by the following equation.

Α0 = tan ⁻¹ (y0 / x0), α1 = tan ⁻¹ (y1 / x1) (5) Further, the three-dimensional coordinate of the measurement point P0 is X0 = s0 × cos (α0) (6) Y0 = s0 × sin (α0) (7) Z0 = L0 (8).

The three-dimensional coordinates of the measuring point P1 are X1 = s1 × cos (α1) (6 ') Y1 = s1 × sin (α1) (7') Z1 = L1 (8 ').

[0064] The distance D between two points of measurement points P0, P1 is determined by D = {(X0-X1) 2 + (Y0-Y1) 2 + (Z0-Z1) 2} 1/2 (9).

Further, as will be described below, it is necessary to obtain a straight line expression that three-dimensionally represents the reference line in order to calculate the depth of the recess or the like. The coordinates of two points corresponding to the specified two points are P0, P
When set to 1, the straight line passing through these two points P0 and P1 is (X-X0) / (X1-X0) = (Y-Y0) / (Y1-Y0) = (Z-Z0) / ( Z1-Z0) (10).

FIG. 13 shows a state in which a cylindrical pipe inner surface 44 is inspected by the endoscope 2 as an object to be measured, and this pipe inner surface 44 has a recess 45 formed by a thinned portion which is thinned by corrosion, for example. Then, the case where the depth of the recess 45 is measured is shown. Therefore, the distal end side of the endoscope 2 is moved so that the recess 45 is placed in the observation field and the laser line 46 projected on the pipe inner surface 44 passes through the recess 45.
The bending portion 12 is set by bending.

At this time, the direction of the laser line 46 is made to coincide with the axial direction of the pipe to reduce the measurement error. The laser line 46 is projected on the inner surface 44 of the pipe so as to pass through the measurement point C where the depth of the recess 45 is to be measured and to a reference plane that serves as a reference for depth measurement (that is, the depth is zero). To do. The portions of the laser line 46 projected on this reference plane are designated as P2 and P3. In this case, FIG.
As shown in, the tip of the direct view type endoscope is attached to the inner surface of the pipe 4
4 does not need to be set parallel to 4 and may be obliquely observed (or imaged).

The laser line 4 is moved by the keyboard 40.
The measurement reference points A and B are set on the six portions P2 and P3, and the measurement point C at which the depth is to be measured is designated. An endoscopic image (in the frame memory 36a or displayed on the display surface of the CRT 37) obtained in this state is as shown in FIG.

As shown in FIG. 14, an image of the concave portion (concave image) 4
The image of the laser line (laser line image) 46 'is superimposed on 5', and the line direction of the laser line image 46 'coincides with the axial direction of the pipe. The laser line image 46 'passes through the concave image 45' and extends on the reference planes on both sides of the concave image 45 ', and the image portions corresponding to P2 and P3 in FIG. 13, that is, the laser line image portions on the reference plane are p2. , P
3 and becomes p2 and p3 corresponding to the two actual points A and B.
The points on the top are a and b, and the point on the image corresponding to the measurement point C is c.

Although the measurement setting procedure and the like have been described with reference to FIG. 13, the setting or designation is actually performed with reference to the endoscopic image of FIG. 14 or in the image as follows. Then, in accordance with these settings or designations, the CPU 38 performs a process of measuring the depth of the concave portion or the like as shown in the flowchart of FIG. 15, for example.

As shown in step S1, the laser line is set so as to pass through the recess. That is, in the image displayed on the CRT 37, the laser line image 46 'is set so as to pass over the concave image 45' (as the image of the measuring object). In this case, the distal end side of the electronic endoscope 2 is moved or curved so that the line direction of the laser line image 46 'becomes parallel to the axial direction of the pipe.

Next, as shown in step S2, two reference points are designated by the cursor in the image. That is, in order to set a reference line that serves as a reference for measurement, the cursor is moved to a position where there is no unevenness on the line of the laser line image 46 ', and two designated points a and b serving as a reference are designated.

Next, as shown in step S3, the three-dimensional coordinates of the actual reference points A and B corresponding to the points a and b are calculated.
That is, when the two designated points a and b are designated, the CPU 3
8 calculates the three-dimensional coordinates of the actual reference points A and B corresponding to the points a and b by the triangulation relational expression.

Further, as shown in step S4, a straight line passing through the reference points A and B is calculated. After calculating the three-dimensional coordinates of the actual reference points A and B, the CPU 38 further executes the following (1
The formula of a three-dimensional straight line passing through the reference points A and B is calculated by the expression 0 ').

Next, as shown in step S5, a point c is designated on the concave portion by the cursor. That is, the cursor is moved to the position of the point where the depth is to be measured on the line of the laser line image 46 'passing through the concave image, and the measurement designated point c is designated. Then, by the designation of the measurement designated point c, the CPU 38 calculates the three-dimensional coordinates of the measurement point C corresponding to the point c as shown in step S6.

Next, as shown in step S7, the length K of the perpendicular line from the measurement point C to the above straight line is given by (12) below.
Calculate from the formula. That is, the depth of the measurement point C (from the reference plane) is calculated.

The above processing contents will be supplementarily described below. Figure 1
3 or 3D of the actual points A, B and C corresponding to the two reference designating points a and b and the measurement designating point c for determining the reference straight line in the state set as shown in FIG. Coordinates (Xa, Ya, Za), (Xb, Yb, Zb
), (Xc, Yc, Zc) can be obtained from the equations (1) to (8).

That is, in the formulas (1) to (8) (and the numbers with ′), the coordinates of the points A, B, and C are P0 or P1.
It is possible to obtain those coordinates by considering them as the coordinates (corresponding to this, the coordinates of a, b, c corresponding to the points A, B, C are also considered as the coordinates of p0 or p1).

The coordinates of points A, B, and C are calculated by the CPU 38 by the function of the measurement calculation section 38a by inputting a coordinate calculation instruction command or the like from the keyboard 40.
Two points a and b for determining a straight line by the program
If A is specified, A and B may be automatically calculated. Further, the equation of the straight line may be calculated.

Further, the equation of the straight line passing through the points A and B becomes the following equation (10 ') in which the sign of the equation (10) is changed. (X-Xa) / (Xb-Xa) = (Y-Ya) / (Yb-Ya) = (Z-Za) / (Zb-Za) (10 ') (10') Straight direction direction cosine 1 , m, n is h = Xb -Xa, i = Yb -Ya, j = with Zb -Za, following equation (11) ^{l = h / (h 2 +} i 2 + j 2) 1/2, m = ^{i / (h 2 + i 2} + j 2) 1/2, n = j / (h 2 + i 2 + j 2) is ^half (11).

As is known in triangulation etc., from the point C (10 ')
The length K of the perpendicular drawn to the straight line of the equation is K ² = (Xc-Xa) ² + (Yc-Ya) ² + (Zc-Za) ^2- {1 (Xc-Xa) + m (Yc-Ya) + n (Zc-Za)} ² (12). In this way, K as the depth of the recess 45 to be obtained can be obtained (in FIG. 14, FIG.
(The length corresponding to the length (depth) K of is indicated by k).

The reference points are not limited to p0 and p1. Further, the number of reference points may be increased to obtain an approximate line such as a quadratic curve or a polygonal line. The process of length measurement is performed in step S1 above.
It is not limited to the order of S7 to S7.
As shown in (A), steps S3 and S4 are replaced with step S5.
It may be performed after. That is, S1, S2, S
The depth of the recess may be calculated by performing steps S5, S3, S4, S6 and S7 in this order.

16A, steps S3, S4, and S6 are collectively performed as shown in FIG. 16A (this process is simply shown as S3 + S4 + S6).
You may make it perform like (B). In FIG. 16 (B), S4 is performed after S3, but S6 is S3 or S3.
You can go in front of 4.

Further, in FIG. 16 (B), steps S2 and S5 may be collectively performed and the processing may be performed as shown in FIG. 16 (C). In short, the above steps S1 to
The order of S6 may be reversed to calculate the depth of the measurement point C.

Although FIG. 13 shows an example of obtaining the depth of the concave portion, the height of the convex portion can be obtained in the same manner. In addition,
By designating A and B at both ends of the recess 45, the recess 4
It is clear that the length of size 5 can be obtained (from equation (9)).

According to the first embodiment, even when the object to be measured is observed from an oblique direction, the depth of the concave portion or the height of the convex portion due to corrosion of the inner surface of the pipe or the like can be accurately obtained. You can

In this embodiment, the depth of the concave portion such as the inner surface of the pipe or the height of the convex portion can be measured even when the object to be measured is observed from an oblique direction.
The laser surface that is emitted from and spreads in a fan shape is the object surface (see FIG. 13).
Then, it is necessary for the portion of the pipe inner surface 44) where the laser line 46 is projected to be perpendicular to the object plane.

In order to make it easier to understand, considering that the inner surface of the pipe is rectangular and the depth of the concave portion existing in the flat plate portion is measured, the concave portion may be observed obliquely. It is necessary for the surface to be perpendicular to the flat plate portion for accurate depth measurement.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the principle of measurement shown in the first embodiment, the intersection point of the origin om of the frame memory shown in FIG. 11 and the optical axis of the image pickup section 19 shown in FIG. 2 and the image pickup surface (photoelectric conversion surface) 18a of the CCD 18, that is, the origin om is It was supposed to match. This embodiment is an embodiment having a correction function for correcting the optical variation even if there is an optical variation.

FIG. 17 shows a state in which the direction of each optical axis and the direction of the central axis of the endoscope are deviated. FIG. 18 shows the coordinates on the frame memory, and FIG. 19 shows the object distance calculated by the origin om. The relationship of the corrected origin coordinates is shown in a table, and FIG. 20 shows the relationship of FIG. 19 in a graph and shows that the corrected origin coordinates can be used for approximation.

FIG. 17 shows a case where the axis of the electronic endoscope 2 and the center of the optical axis of the image pickup system are deviated by an angle δ, and the axial direction of the electronic endoscope 2 is deviated by an angle δ ′. Indicates. In such a case, even if the object distance L to the point P0 is calculated using the equation (3), the error in the equation (3) becomes large because the H changes in accordance with the object distance L.

Therefore, by performing the following correction, it is possible to obtain an approximate value close to the actual object distance L, and even if there are variations in the optical system, the depth can be obtained by using this approximate value. The height can be calculated accurately.

FIG. 18 shows the center om on the frame memory and the optical axis center op of the image pickup optical system corresponding to the case of FIG. 17, and as shown in FIG.
It is assumed that m and the optical axis center op of the imaging optical system are displaced.

In FIG. 17, the laser line passes through the point P0 and extends in the direction perpendicular to the plane of the drawing (in FIG. 18, the vertical direction, that is, the y-axis direction). Further, in FIG. 17, the object plane 15 is shown in a state parallel to the tip surface of the electronic endoscope 2.
Now, consider a case where the object distance L to a point P0 of an object is measured. Therefore, it is defined as follows.

Om: the origin (0, 0) of the coordinate system set at the center on the frame memory, op: the optical axis center coordinate (xop, yop) of the imaging system on the frame memory, p0: at the point P0 Coordinates on the corresponding frame memory (x0
, y0), ks: distortion correction coefficient of the imaging optical system, fc: coefficient for converting to an image height on the frame memory, θ: angle formed between the optical center of the imaging optical system and O-P0 (FIG. 17)
), Α: the angle formed by the x-axis and op −p0 on the frame memory, and px, py, and r are defined as follows.

Px = xop−x0, py = yop−y0 (13) r ² = px ² + py ² (14) That is, the length px of the x-coordinate component and the length py of the y-coordinate component from the optical axis center of the point p0, and the length r to the point p0.
By defining α = tan ⁻¹ (py / px) (15) θ = ks · sin ⁻¹ (r / fc / ks) (16) L = H / (cos α · tan θ) (17) Becomes

Although L is an object distance based on H, the accurate object distance L cannot be calculated because H is constant. In this state (that is, assuming that H is constant and changing the known object distance L), an example of the calculation result using the equation (17) is shown in the table of FIG. The first column of this table shows the actual object distance, and the second column shows the object distance from the origin op.

As can be seen from these numerical values, there is a difference between the object distance based on the origin op and the actual object distance, and the ratio of the deviation increases as the distance decreases. So H
Is the corrected origin coordinates shown in the third column in the table of FIG. 19 as a result of the correction of the origin op in order to compensate for the change in the calculation. Origin o
A graph of the object distance using p and the corrected origin coordinates n is shown in FIG. When the approximation formula is applied to the graph of FIG. 20, it becomes as follows.

Let q: object distance calculated based on the origin op, n: corrected origin coordinates, and let t be log n = a1 (log q) ³ + a2 (log q) ² + a3 (log q ) + A4 The constants a1, a2, a3, so as to satisfy the approximate expression by (18)
Determine a4.

Then, xc = 10 (log n) (19) is defined as the x component of the corrected origin coordinates. Based on this result, the following formula (20) is used instead of formula (13) to calculate formulas (14) to (19), and a value close to the actual object distance is obtained.

Px = xc−x0, py = yop−y0 (20) Since a value close to the actual object distance is obtained in this way, the point P0 can be obtained by using the expressions corresponding to the expressions (4) to (8). Of 3
Dimensional coordinates can be determined. Since other points can be determined in the same manner, the depth or height can be calculated as in the first embodiment.

In this embodiment, the spreading direction of the laser light is made to coincide with the vertical direction of the screen. That is, as shown in FIG. 18, the line direction of the laser line image 46 'is made parallel to the y-axis direction. Therefore, in this case, the movement of the laser line image 46 'on the frame memory due to the change of the object distance is only in the x-axis direction. Therefore, the correction of equation (20) is x
A simple one only in the axial direction will do.

As a result, the amount of calculation of the CPU 38 and the number of correction coefficients can be reduced. Further, the larger the distance H between the laser aligner projection unit 22 and the image pickup unit 19, the larger the parallax when measuring the unevenness, and the resolution capability of the measurement is improved. When the outer diameter of the endoscope is limited, H can be maximized by projecting the laser line perpendicularly to the straight line connecting the laser line projection unit 22 and the optical center of the imaging system in order to increase H. The calculation formula of this embodiment requires the following parameters for each scope.

Op (xop, yop): center coordinate of optical axis on frame memory, ks: distortion correction coefficient of optical system, fc: coefficient for converting actual image height to image height on frame memory, a1 , A2, a3, a4: Coefficients of approximate expression, these parameters are obtained by measurement in advance for each scope (electronic endoscope), and are stored in a recording medium such as a floppy disk as information for correcting the obtained parameters. Keep a record. When the parameters recorded on the recording medium are input to the measuring unit 4, the configuration as shown in FIG. 21 is used to read the parameters via the floppy disk drive 34 as a recording / reproducing device.
It may be input to the CPU 38 that performs correction calculation.

FIG. 21 is provided with a floppy disk drive (device) 34 and a hard disk drive (device) 30 as an information recording / reproducing device for performing measurement calculation and correction calculation by the CPU 38. The above parameters are recorded in the floppy disk drive 34 (the floppy disk that is recorded and reproduced by the floppy disk drive) and is read from the floppy disk to the CPU 38 at the start of use of the scope.
It is recorded in the hard disk drive 30 and its parameters are referred to as necessary. In addition to the above parameters, other parameters or data required for measurement are recorded on the hard disk drive 30.

When the same scope is used repeatedly, it is only necessary to refer to the hard disk 30, and it is not necessary to fetch the parameters from the repeated floppy disk. When connecting another measuring endoscope to the same measuring unit 4, the parameters are exchanged from the floppy disk.

As shown in FIG. 21, since the means for inputting the parameters necessary for the measurement and varying for each endoscope to the measuring unit 4 are provided, the measurement error is small and the accurate measurement can be performed. Therefore, it is possible to provide a measuring endoscope system or an endoscope apparatus whose measurement accuracy does not change even if the endoscope is replaced. Other effects are the same as those of the first embodiment.

Parameters necessary for measurement are recorded or registered in the hard disk drive 30 in advance, and when an unregistered electronic endoscope is connected to the hard disk drive 30, it is registered. It is also possible to display that there is no such information and prompt the user to insert the floppy disk in which the parameter is recorded. In addition,
FIG. 21 shows a configuration in which the LD drive circuit 39 is built in the electronic endoscope 2, and the LD drive circuit 39 is supplied from a power supply 79 built in the measurement unit 4 side via a power supply line.
It supplies the power necessary for the operation of.

Next, a third embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 23, the electronic endoscope 82 of this embodiment is a side-view type in which a side direction orthogonal to the axis of the insertion portion is observed. Also, inside the laser light source 5,
ROM 83 as a semiconductor memory storing parameters necessary for measurement when each electronic endoscope 82 is used
(See FIG. 24) is provided so that the CPU 38 in the measurement unit 4 can access the CCU connector 84.

Then, when the CCU connector 84 of the electronic endoscope 82 is connected to the measuring unit 4, the level of the terminal T1 constituting the connection detecting means changes from "L" to "H", so that the electronic endoscope 82 is changed. A connection signal connected to the measuring unit 4 is sent to the interrupt terminal C1 of the CPU 38. CP
U38 reads out the parameters necessary for measurement from the ROM 83 based on the connection signal, and the connected electronic endoscope 82
With the correct parameters set for, it is possible to perform highly accurate measurement.

As shown in FIG. 24, the laser diode 56
Is driven by an LD drive circuit 39 having an APC (automatic power control) function, and its emission intensity can be adjusted by a laser line intensity adjustment knob 85, for example, by changing a reference current value for determining the emission intensity. Power is supplied to the drive circuit 39 by the CCU connector 84.
Power is supplied from the power supply circuit 79 inside the measurement unit 4 via.

Further, as shown in FIGS. 25 (A) and 25 (B), C
Set the line width of the cursor displayed on RT37 to d1 or d2
As described above, the color can be arbitrarily changed by an instruction from the keyboard 40, and the color can be arbitrarily changed by an instruction from the keyboard 40 such as blue or white.

As shown in FIG. 23, the endoscope distal end portion 11 includes a side-view type image pickup system 92 using a first prism 91 and a second-view type image pickup system 92.
It has a laser line projection portion 95 that is bent laterally by a prism 93 and is expanded linearly by a cylindrical lens 94. The laser light transmitted by the optical fiber 23 is emitted from the tip surface thereof, passes through the collimator lens 87, becomes a parallel light beam, is laterally bent by the second prism 93, and is further spread in a line by the cylindrical lens 94 to be covered. It is projected through the glass onto the object plane 89a (or 89b) (in FIG. 22, the object plane is indicated by 89).

The spread direction of the laser beam emitted from the laser line projection optical system 95 (or the direction of the laser line 96) is shown by 9 in FIG.
As shown by 6'and 96 '', the setting is made so as to coincide with the horizontal direction (horizontal direction) of the image. The effect in this case is almost the same as that of the first embodiment.

FIG. 26A shows an image when the object distance is short, and FIG. 26B shows a case where the object distance is long. That is, images projected on the object plane 89a or 89b in FIG. 23 are shown in FIGS. 26 (A) and 26 (B), respectively. In this way, the laser line 96 'or 96 "on the image moves in the y-axis direction according to the change in the distance.

The laser light source unit 53 'of this embodiment has the structure shown in FIG. FIG. 27 corresponds to FIG. 5B of the first embodiment. The difference between this embodiment and the first embodiment is that, as shown in FIG.
7 is provided with a wedge prism 98. Wedge prism 9
The operation of No. 8 will be described with reference to FIG.

The optical axis 99a of the laser beam 99 is bent by the wedge prism 98 as shown by the optical axis 100a, and enters the optical fiber 23. The optical axis 100a is inclined with respect to the central axis 23d of the fiber 23, and the light beam enters the optical fiber 23 obliquely. Since the incident angle of the light obliquely incident on the optical fiber 23 is substantially preserved, the intensity distribution of the light emitted from the fiber 23 changes.

FIG. 29 shows the laser light source unit 5 of this embodiment.
The intensity distribution of the light beam emitted from the laser line projection unit 95 when 3'is used is shown. In FIG. 29, the vertical axis represents the light intensity and the horizontal axis represents the spread angle. The solid line shows the case where the wedge prism 98 is not used, and the broken line shows the case where the wedge prism 98 is used. The solid line is close to the Gaussian curve, but the broken line shows that the light intensities are averaged. In order to enhance the effect of the wedge prism 98 according to this embodiment, it is more effective to use a multimode fiber as the optical fiber 23.

When the intensity distributions of the laser lines are averaged as described above, it is convenient that the laser lines have no unevenness in intensity when the plane is observed almost vertically, for example, when measuring the surface of the turbine blade. On the contrary, when the wedge prism 98 is not used, the optical axis of the laser line projection unit 95 is directed toward the center of the pipe, that is, when the inner surface of the pipe is observed in the axial direction, that is, the intensity of the laser line is high. It is convenient when the part is heading to the far point.

Various length measurement calculations of this embodiment are performed in the first embodiment,
Although it is similar to the second embodiment, the origin coordinates to be corrected in the third column in the table of FIG. 19 are for the y axis.
According to this embodiment, the CPU 38 can read the correct parameter set for the electronic endoscope 82 only by attaching the electronic endoscope 82 to the measuring unit 4, so that the parameter It is possible to provide an endoscope apparatus that can prevent forgetting of settings and erroneous settings and can perform highly reliable measurement. Further, in the present embodiment, since the width and color of the cursor can be changed, even a person with a weak color can work efficiently.

The laser line projected on the object plane is displayed in red on the observed image from the wavelength range of the laser beam, but the color tone of the image is changed (for example, color emphasis or to the display means side). The output color signals may be exchanged) so that even a person with color weakness can clearly identify the laser line displayed on the display surface so that the measurement can be performed efficiently.

Further, as the illumination light source 3, for example, R,
A field-sequential illumination light source that sequentially emits G and B illumination light to the object side, and CC is generated under the field-sequential R, G, and B illumination light.
In the case of the frame-sequential imaging method in which images of three color components are obtained by sequentially capturing images in D18, and these are combined into a color image, the timing of emitting the laser light to the object side is set to the frame-sequential. By making it possible to change in synchronization with the illumination light, it is possible to make the color of the laser line displayed on the display surface easily distinguishable from the object plane.

For example, when the object plane is red, the output image of the CCD 18 is set by setting the timing of emitting the laser beam to the object plane to be synchronized with the timing of the G or B illumination light. The image is captured (recognized) as a laser line having a G or B wavelength component, and it is easy to identify the laser line projected on the object plane on the image captured in this state. That is, if the emission timing of the laser light is set to the timing of the illumination light in the wavelength range different from that of the color tone of the object surface, it does not matter much to the wavelength of the laser diode 56 actually used ( In practice, the CCD 18 is limited to a wavelength range in which the CCD has sensitivity), so that the laser line can be easily identified on the image.

FIG. 30 shows how the depth of the groove in the flat plate in the fourth embodiment of the present invention is measured by an electronic endoscope.
In this embodiment, for example, in the first embodiment, a judgment function for judging whether or not the laser projection plane is set perpendicular to the surface of the measuring section is provided, and this judgment function is shown in FIG.
CPU 38 of FIG.

The solid line in FIG. 30 is the flat plate 1 as the measurement object.
11 shows a state in which the groove 112 is observed obliquely with the electronic endoscope 2 used in the first embodiment, and the laser line projection unit 22 projects the laser line 46 in this oblique observation state. In this case, the solid line shows the state where the laser surface 113 is set correctly, and the two-dot chain line shows the state where the laser surface 113 'is not set correctly.

That is, in the case of a solid line, the laser surface 113 forms an angle μ with the surface of the flat plate 111 on which the laser line 46 is projected.
Is 90 °, and in this state, the depth can be obtained by setting the measurement point C on the laser line in the groove 112 and finding the length K of the perpendicular to the straight line passing through the reference points A and B. it can.

On the other hand, in the case of the two-dot chain line, the laser surface 1
13 has an angle ν formed with the plane of the flat plate 111 on which the laser line 46 is projected smaller than 90 °, and in this state, a measurement point C ′ on the laser line in the groove 112 is set to set reference points A and B.
Even if the length K'of the perpendicular to the straight line passing through is calculated, the correct depth cannot be calculated. Therefore, in the case of such an object to be measured, the laser line 46 is set to intersect the edge ab of the groove 112 at a right angle. The surface of the flat plate 111 is indicated by Σ. Alternatively, the length K ′ of the perpendicular is measured at several points while changing the angle μ of the endoscope, and the smallest length K ′ is set to the correct value K.

According to the fourth embodiment, in addition to the operation and effect of the first embodiment, it is possible to judge whether or not the measurement can be performed correctly. In order to determine the reference straight line, two points A and B may be designated on the laser line of the reference surface, but two or more points may be designated.

FIG. 31 shows a state in which the inner surface 100 of the pipe is inspected by the endoscope 2. The inner surface 100 of the pipe has a convex portion 101 due to melting of welding.
It shows the case of measuring the height of. In general, the quality of welding is judged based on this amount of welding.

Therefore, the distal end side of the endoscope 2 is moved or the bending portion 12 is moved so that the convex portion 101 is within the visual field and the laser line 102 projected on the inner surface 100 of the pipe passes through the convex portion 101. Set it by bending it.

At this time, the direction of the laser line 102 is made to coincide with the axial direction of the pipe to reduce the measurement error. In addition, the laser line 102 passes through the measurement point C where the height of the convex portion 101 is to be measured, and extends on the reference surface which is the reference for height measurement (that is, the height is zero) on the pipe inner surface 100. To project. The portions of the laser Iran 102 projected on this reference plane are designated as P2 and P3. in this case,
As shown in FIG. 31, it is not necessary to set the front end surface of the direct-view endoscope to be parallel to the inner surface 100 of the pipe, and the observation (imaging) may be performed obliquely.

The laser line 1 is moved by the keyboard 40.
The measurement reference points A and B are set on the 02 parts P2 and P3, and the measurement point C whose height is to be measured is designated. The endoscopic image obtained in this state (displayed on the frame memory 36 or on the display surface of the CRT 37) is as shown in FIG.

As shown in FIG. 32, a laser line image 102 'is superimposed on a convex image 101',
The line direction of the laser line image 102 'coincides with the axial direction of the pipe. In addition, the laser line image 102 'has a convex portion 10
1 ', and extends on the reference planes on both sides thereof.
Image portions corresponding to P2 and P3, that is, laser line image portions on the reference plane are p2 and p3, and points on p2 and p3 corresponding to the two actual points A and B are a and b. ,
The point on the image corresponding to the measurement point C is c.

Although the settings for measurement have been described with reference to FIG. 31, the settings or designations are actually made on the endoscopic image of FIG. 32 as follows. Then, according to these designations, the CPU 38 performs the length measurement process in the following order of steps S11 to S17, for example.

S11. The laser line image 102 'is set to pass on the convex portion 101' on the image displayed on the CRT 37. In this case, the electronic endoscope 2 is arranged so that the line direction of the laser line image 102 'is parallel to the axial direction of the pipe.
The tip side of is moved or curved.

S12. The cursor is moved to a position where there is no unevenness on the line of the laser line image 102 ', and two designated points a and b serving as a reference are designated. The number of designated points may be three or more. S13. The CPU 38 is designated by the designation of the two designated points a and b.
Calculates the three-dimensional coordinates of the actual reference points A and B corresponding to the points a and b by the relational expression of triangulation. S14. The CPU 38 further uses the above equation (10 ') to
A straight line passing through the reference points A and B is calculated.

S15. Further, the cursor is moved to the position of the point whose height is to be measured on the line of the laser line image 102 ', and the measurement designated point c is designated. S16. By the designation of the designated measurement point c, the CPU 38 calculates the three-dimensional coordinates of the measurement point C corresponding to the designated point c by the triangulation relational expression.

S17. The length K of the perpendicular line drawn from the measurement point C with respect to the above straight line is obtained from the equation (12). That is, the height of the measurement point C (from the reference plane) is calculated. A supplementary explanation will be given below.

In the state set as shown in FIG. 31 or 32, the actual points A, B and C respectively corresponding to the two reference designated points a and b and the measurement designated point c in order to determine the straight line as the reference. Three-dimensional coordinates (Xa, Ya, Za) (X
b, Yb, Zb) (Xc, Yc, Zc) are (1) to (8)
It can be obtained from the calculation formula shown in the formula.

That is, in the equations (1) to (8) (and the numbers with '), the coordinates of points A, B and C are P0 or P, respectively.
Considered as 1 coordinate. (Corresponding to this, each point a, b, c
The respective coordinates of are also regarded as the coordinates of p0 or p1),
You can find their coordinates.

The coordinates of the points A, B and C are calculated by the CPU 38 by the function of the measurement calculation 38a by inputting a coordinate calculation instruction command or the like from the keyboard 40. If two points a and b for determining the straight line are designated by the program, A and B may be automatically calculated. Further, the equation of the straight line may be calculated.

The straight line passing through the points A and B is (10 '),
Equation (11) is used. Further, the length K of the perpendicular line drawn from the point C of the convex portion to the straight line of the equation (10) is obtained by the equation (12). In this way, the height K of the desired convex portion can be calculated in the same manner as the concave portion.

Next, a fifth embodiment of the present invention will be described. This embodiment differs from the above-described embodiments in that a projection means for projecting a line-shaped shadow on the object plane 15 is used and the concave portion is calculated using a curved line as a reference line instead of a straight line.

FIG. 33 shows an endoscope apparatus 131 according to the fifth embodiment of the present invention. The endoscope 132 used in this endoscope device 131 has a light guide connector 139 without the laser light source unit 53 in FIG. 2, and this light guide connector 139 is connected to the light source device 3. Further, the endoscope 132 has an optical fiber 2 for transmitting laser light.
3 and the laser line projection unit 22 are not provided. Instead of these, the endoscope 132 is provided with a light-shielding mask 133 for projecting a line-shaped shadow on the tip surface of the light guide 10 as shown in detail in FIG.

As shown in FIG. 34, the illumination window 14 adjacent to the observation window 16 (only one in this embodiment) is provided with the illumination convex lens 135 protected by the cover glass 134, and the light guide 10 is provided. The illumination light transmitted in step (1) is emitted so as to spread forward through the convex lens 135.

The tip portion of the light guide 10 is fixed to the tip portion 11 with a mouthpiece 136, and in front of the end surface of the light guide 10, for example, a glass plate 137 as a disc-shaped parallel flat plate.
Is attached, and the convex lens 135 of this glass plate 137 is attached.
As shown in FIG. 35, the line-shaped light-shielding mask 1 is provided on the side surface.
33 is provided. The light-shielding mask 133 is formed by applying black paint in a line shape. The distance from the light-shielding mask 133 to the convex lens 135 is the convex lens 13.
It is almost equal to the focal length of 5. And this shading mask 1
The light is blocked at the 33rd portion, and a line-shaped shadow 138 is projected on the object plane 15 side. In FIG. 34, the line direction of the light shielding mask 133 is a direction perpendicular to the paper surface.

In FIG. 35, the two-dot chain line indicates the objective lens system 17 and the CCD 18, and the line direction of the light-shielding mask 133 is parallel to the vertical or horizontal direction of the square or rectangular image pickup surface of the CCD 18.

The measuring unit 4'in this embodiment has a structure in which the laser diode drive circuit 39 is removed from the measuring unit 4 of FIG. 2 and a curve calculating unit 38b 'is provided in place of the line calculating unit 38b in the CPU 38. . The other hardware configuration is the same as that of FIG. 2, and the same components are denoted by the same reference numerals and the description thereof is omitted.

In this embodiment, since the shadow projecting means 140 for forming a line-shaped shadow is realized by providing the light shielding mask 133 in the illumination optical system portion, the endoscope device 131 is provided.
The configuration is simpler than that of the first embodiment.

FIG. 36A shows an inner surface 44 of a cylindrical pipe.
7 shows how the recessed portion 45 such as the reduced thickness portion is measured. When the shadow 138 projected on the inner surface 44 of the pipe is inclined with respect to the axis of the pipe, the image 141 as shown in FIG. 37 is displayed on the CRT 37. As can be seen from this image 141, the shadow 138 'becomes a curve. In this embodiment, the three-dimensional expression of the curve projected on the inner surface 44 of the pipe is obtained and the depth of the recess 45 is measured as follows.

For example, six points of r, s, t, u, v, and w are designated by a cursor at arbitrary positions on the curve excluding the concave portion in the image 141. Next, q is designated as a depth measurement point on the curve passing through the concave portion.

With these designations, the CPU 38 determines the three-dimensional coordinates of the point corresponding to the point designated in the image from (1) to
It is calculated using equation (8). Points r, s, t, u, v,
The calculated three-dimensional coordinates of the points R, S, T, U, V, W, Q corresponding to w, q are shown in FIG. 36 (B).

When an expression of an approximate curve representing a curve passing through six points R, S, T, U, V and W represented by three-dimensional coordinates on the inner surface 44 of the pipe is obtained, for example, as shown in FIG. The recess 4 in the pipe inner surface 44 on which the shadow 138 is projected
Consider a coordinate system in which the plane of the projection plane 139 cut by the shadow 138 projected so as to pass through 5 is the YZ coordinate system, for example. Specifically, coordinate conversion to this projection plane 139 may be performed.

Thus, the projection plane 139 including the shadow 138
By considering the above, the curved portion projected on the pipe inner surface 44 excluding the concave portion of the projected shadow 138 can be approximated by a curved line in the plane as follows. As shown in FIGS. 12 (A) and 12 (B), arbitrary points P0 and P1 on the projected line are located on a line parallel to the Y axis where the X coordinate is H away from the Y axis (that is, X = −). Since it exists in H), the value of X coordinate is -H
Coordinate transformation that draws only (that is, three-dimensional coordinates (X-H, Y,
Z) as a new three-dimensional coordinate (X, Y, Z)), the projection plane 139 exists in the YZ plane of X = 0, and YZ
It is possible to think in terms of coordinate system. Since the value of X is constant, a YZ coordinate system on the YZ plane where X = H may be adopted.

More specifically, the recess 45 is formed on the inner surface 44 of the pipe.
A curve of a portion of the shadow 138 projected so as to pass through except for the concave portion 45 is approximated by a quadratic equation and used as a reference curve for depth measurement. General formula of quadratic curve aY ² + 2hYZ + bZ ² + 2gY + 2fZ + c = 0 (21) where a, h, g, b, f, c are constants in the formula (21). Of (Y,
Z) By substituting the coordinates, these six formulas can be made simultaneous to obtain the six constants a, h, g, b, f, and c.
That is, since the six constants a, h, g, b, f, and c are determined, the expression of the reference curve can be specifically obtained.

Next, the depth of the recess 45 is obtained. In the quadratic equation represented by the equation (21), the tangent line of any point (Y1, Z1) can be represented by the following equation.

Y (aY1 + hZ1 + g) + Z (hY1 + bZ1 + f) + (gY1 + fZ1 + c) = 0 (22) where A ′ = aY1 + hZ1 + g B ′ = hY1 + bZ1 + f C ′ = gY1 + fZ1 + c = B ′ (Z + C ′ + 0) + A′C23 + Becomes

A point Q (Yq, Z) for obtaining the depth of the recess 45.
The length D of the perpendicular line drawn from q) to the tangent line 143 represented by the equation (23) is represented by D = | A′Yq + B′Zq + C ′ | / √ (A ′ ² + B ′ ² ) (24).

Here, when the point Q for obtaining the depth exists on the convex side of the curve expressed by the equation (21), the arbitrary point (Y1, Z1) is set in the range 142 of M in FIG. The depth K is the value at which the length D of the perpendicular line is maximum at each point.

The point Q for which the depth is to be obtained is (2
When it exists on the concave side of the curve represented by the equation (1), the arbitrary point (Y1, Z1) is changed within the range 142 of M in FIG. 38, and the length D of the perpendicular line at each point. The depth D is determined to be the smallest value of D.

Although the quadratic equation is used as the reference line in this embodiment, other mathematical functions may be used. Further, it is apparent that not only the depth of the concave portion 45 due to the thinned portion but also the height of the convex portion is obtained.

Further, in this embodiment, since the means for projecting a shadow by using the illumination light for observation is formed, the laser light source is not required and most of the existing endoscope apparatus are used. Since it can be configured with a slight modification, the endoscope system capable of measuring the depth of the concave portion or the height of the convex portion can be realized at low cost.

In the above-described embodiment, an arbitrary point is designated in the observed image of the line-shaped light or the line-shaped shadow on the projected object surface, and the approximate expression of the three-dimensional reference line passing through the designated point is obtained. After that, a measurement point such as a recess is specified, and the depth of the recess is calculated by obtaining the length of a perpendicular line from the three-dimensional coordinate position of the measurement point to the reference line.

On the other hand, as in the sixth embodiment described below, a reference point on the projected line is used to obtain the three-dimensional expression of the reference line, and the measurement point desired to be measured is designated. It is also possible to obtain the depth of the concave portion by obtaining the length of a perpendicular line drawn from the three-dimensional coordinate position of the measurement point to the reference line.

In each of the above embodiments, the endoscope used for length measurement is not limited to the electronic endoscope.
A TV camera that has a solid-state image sensor built in the eyepiece of an optical endoscope (optical scope) that has an image guide function that transmits an optical image by forming an optical image using an objective lens The attached TV camera scope may be used.

Further, the display device for displaying the image is a CRT3.
The number is not limited to 7, and a liquid crystal display, a plasma display or the like may be used. Further, a combination of the above-mentioned embodiments partially or in part to form different embodiments also belongs to the present invention.

[Additional Notes] 2. The endoscope apparatus according to claim 1, wherein when the surface of the object is a cylindrical surface, a reference line passing through the surface is set in a direction parallel to the axis of the cylindrical surface. 3. The endoscope apparatus according to claim 1, wherein, when obtaining the three-dimensional coordinates of the position designated by the position designating means, at least one of an error and a distortion of an objective optical system of the endoscope is corrected. Have. 4. The endoscope apparatus according to claim 1, wherein the reference line projecting means emits linear light from laser light supplied from a semiconductor laser, and forms the reference line on the object by the linear light. To do. 5. The endoscope apparatus according to claim 1, wherein the reference line projection means projects a line-shaped shadow onto the object,
The reference line is formed by the line-shaped shadow.

6. The endoscope apparatus according to claim 1, wherein the reference line projecting unit projects a line-shaped shadow by a line-shaped light shielding unit provided in the illumination optical system onto the object, and the line-shaped shadow causes the line-shaped shadow to be projected. Form a reference line. 7. The endoscope apparatus according to appendix 4, wherein the endoscope has a transmission means for transmitting illumination light to the illumination optical system, and the transmission means generates illumination light provided outside the endoscope. And a laser light source having the semiconductor laser in the connector portion. 8. The endoscope apparatus according to attachment 4, further comprising an optical fiber that transmits the laser light to the reference line projection means, and a wedge-shaped prism is provided on an end surface of the optical fiber to which the laser light is supplied. 9. The endoscope apparatus according to claim 1, wherein a line direction of the reference line projected from the reference line projecting unit to the object side is parallel to a vertical or horizontal direction of a rectangular or square imaging surface of the image sensor. Is. 10. The endoscope apparatus according to appendix 3, wherein the correction unit has a recording unit that records, for a plurality of endoscopes, information for correcting at least one of error and distortion of each objective optical system, The correction means reads out information corresponding to an endoscope that is actually used and performs correction before performing the measurement.

11. The endoscope apparatus according to appendix 3, wherein each endoscope has a semiconductor memory in which information to be corrected by the correction unit is recorded, and the correction unit reads out the information from the endoscope to be used for correction. I do. 12. The endoscope apparatus according to claim 1, wherein the arithmetic means is configured by using a CPU. 13. The endoscope apparatus according to claim 1, wherein the endoscope is a direct-viewing type having an observation visual field in a direction parallel to an axial direction of the insertion portion. 14. The endoscope apparatus according to claim 1, wherein the endoscope is a side-view type having an observation visual field in a direction orthogonal to an axis of the insertion portion. 15. The endoscope apparatus according to claim 1, wherein the position designating means is cursor display means for displaying a cursor at an arbitrary position in the image.

16. The endoscopic device according to claim 1, wherein the calculation means calculates three-dimensional coordinate positions respectively corresponding to a plurality of points designated on a reference line passing through the surface in the image, and the three-dimensional coordinates are calculated. The expression of the approximate line is obtained from the calculation for calculating the expression of the line passing through the coordinate position. 17. On the surface of the object in which the concave portion or the convex portion is present, a line-shaped light or shadow is projected from the reference line projection means provided on the tip side of the endoscope equipped with the image pickup means, and the surface and the concave portion or the convex portion are A first step of forming a passing reference line, and the object is imaged by the imaging means,
A second step of designating a plurality of points on a reference line passing through the surface in the image of the object displayed by the display means, and a reference line passing through the concave portion or the convex portion in the image of the object. A third step of designating a measurement point whose depth or height is to be measured, and an approximation line that three-dimensionally represents a reference line that passes through the surface by designating the plurality of points and serves as a measurement reference. And calculating the three-dimensional coordinates of the measurement point, and further calculating the distance from the measurement point to the approximate line to calculate the depth of the concave portion or the height of the convex portion. 4. The method for measuring the depth of a concave portion or the height of a convex portion, which comprises the step 4).

18. 18. The measuring method according to claim 17, wherein the reference line passing through the surface and the concave portion or the convex portion is projected so as to cut the surface and the concave portion or the convex portion substantially vertically. 19. The measurement method according to attachment 17, wherein the approximate line is a straight line. 20. The measurement method according to attachment 17, wherein the measurement point and the plurality of points are designated by a cursor that moves in the image. 21. In the measurement method according to attachment 17, the calculation of the expression of the approximate line, the calculation of the three-dimensional coordinates, and the calculation of the depth or height are performed using a CPU. 22. The measurement method according to attachment 17, wherein the reference line-shaped light has a wavelength of 600 to 700 nanometers. 23. In the measurement method according to attachment 20, at least one of the width of the cursor and the display color of the cursor can be selected.

24. The measurement method according to attachment 17, wherein the designation of the plurality of points is two or three. 25. The measurement method according to attachment 19, wherein the distance is calculated by calculating the length of a perpendicular line drawn from the measurement point to the approximate line, and the length of the perpendicular line is defined as the depth of the concave portion or the height of the convex portion. To do. 26. The measurement method according to attachment 17, wherein the approximate line is a curve. 27. The measurement method according to attachment 26, wherein the distance is calculated by calculating the length of a perpendicular line drawn from the measurement point to the tangent line of the curve, and the length of the perpendicular line is calculated as the depth of the concave portion or the height of the convex portion. Satoshi 28. The measurement method according to attachment 17, wherein the designation of the plurality of points is 6 points.

29. On the surface of the object in which the concave portion or the convex portion is present, a line-shaped light or shadow is projected from the reference line projection means provided on the tip side of the endoscope equipped with the imaging means,
A first step of forming a reference line passing through the surface and the concave portion or the convex portion; and a reference line passing through the surface in the image of the object imaged by the image pickup means and displayed by the display means. A second step of designating a plurality of points on the top surface, passing through the surface, and calculating a formula of an approximate line that three-dimensionally represents a line serving as a reference for measurement; and in the image of the object, A third step of calculating a three-dimensional coordinate of the measurement point by designating a measurement point whose depth or height is to be measured on a reference line passing through the concave portion or the convex portion, and from the measurement point to the approximate line And a fourth step of calculating the depth of the concave portion or the height of the convex portion to calculate the distance of the concave portion or the height of the convex portion.

[0174]

As described above, according to the present invention, an elongated insertion portion, an illumination optical system which is provided on the distal end side of the insertion portion and which emits illumination light to an object, and illumination by the illumination light An objective optical system that forms an image of the target object, and a reference line projection unit that projects a reference line that passes through a concave portion or a convex portion that is a measurement target existing on the surface of the target object,
An endoscope including an image pickup device for photoelectrically converting an image based on the objective optical system, signal processing means for performing signal processing on the image pickup device and generating a video signal, and by inputting the video signal A display means for displaying an image corresponding to the object on which the reference line is superimposed, a position designating means for designating an arbitrary position of the image, and a reference line passing through the surface is regarded as a reference line for measurement. Calculation of an approximate line expression that three-dimensionally represents a reference line, calculation of a three-dimensional coordinate position corresponding to a point designated by the position designating means on a reference line passing through the concave portion or the convex portion, and the approximation. Since a calculation means for calculating the distance between the line and the three-dimensional coordinate position to calculate the depth of the concave portion or the height of the convex portion is provided, a riff passing through the surface in an oblique direction. Even when the lens line is projected, the depth etc. can be easily measured by obtaining the distance from the point specified on the reference line passing through the concave portion or the convex portion with respect to the approximate line which is the reference line for the reference line. There is.

[Brief description of drawings]

FIG. 1 to FIG. 15 relate to a first embodiment of the present invention, and FIG. 1 is an external view showing the overall configuration of an endoscope apparatus of the first embodiment.

FIG. 2 is an overall configuration diagram of an endoscope device.

FIG. 3 is a cross-sectional view showing the structure of the distal end portion of the endoscope.

FIG. 4 (A) is a plan sectional view of a laser line projection unit provided at the distal end of the endoscope, FIG. 4 (B) is a side sectional view of the laser line projection unit, and FIG. 4 (C) is a laser line. The figure which shows the structure of the plane parallel plate used for the projection part.

5 (A) is a cross-sectional view of a laser line light source having a fine movement mechanism of a die, FIG. 5 (B) is a cross-sectional view taken along the line AA of FIG. 5 (A), and FIG. 5 (C) is a comparison. FIG. 5D is a cross-sectional view showing the fine movement mechanism of the die in the prior art for the purpose of FIG. 5D.
-E line sectional drawing.

FIG. 6 is a block diagram showing a schematic configuration of an electric system of the endoscope apparatus.

FIG. 7 is a diagram in which a laser line is projected on an object plane parallel to the tip surface.

8 is an explanatory diagram of a relationship between a measurement point and an optical system at a BB cross section position in FIG. 7.

FIG. 9 is an explanatory diagram showing a state in which a laser line is projected onto an object surface that is oblique to the tip surface.

FIG. 10 is a side view of FIG. 9.

FIG. 11 is an explanatory diagram showing a captured image in FIG. 9;

12 (A) and 12 (B) are explanatory views showing a relationship between a measurement point and an optical system.

FIG. 13 is an explanatory diagram showing a state where a laser line is projected on the inner surface of a pipe having a recess.

FIG. 14 is an explanatory diagram showing a captured image corresponding to FIG. 13.

FIG. 15 is a flowchart showing the processing contents for calculating the depth of a recess.

16 (A) to 16 (C) are flowcharts showing the processing sequence of the modified example of FIG.

FIG. 17 is an explanatory diagram showing a state in which there is an optical shift.

FIG. 18 is an explanatory diagram showing an image corresponding to FIG. 17 on a frame memory.

FIG. 19 is a table showing the relationship between the actual object distance and the corrected origin coordinates when there is an optical shift.

FIG. 20 is a graph showing a state in which the relationships in the table of FIG. 19 are approximated by an approximate expression.

FIG. 21 is a block diagram of an electric system in the second embodiment.

FIG. 22 is an overall configuration diagram of an endoscope apparatus according to a third embodiment of the present invention.

FIG. 23 is a cross-sectional view of the tip of the electronic endoscope.

FIG. 24 is a block diagram of an electric system of the endoscope device.

25 (A) and 25 (B) are explanatory views showing a cursor on a CRT.

26 (A) and 26 (B) are explanatory views showing the movement of a laser line on an image.

FIG. 27 is a cross-sectional view showing a laser light source unit.

28 is a cross-sectional view showing details of an incident portion of the optical fiber in FIG. 27.

FIG. 29 is a characteristic diagram showing the intensity distribution of a laser line.

FIG. 30 is an explanatory diagram showing a state of measuring the depth of a groove in the fourth embodiment of the present invention.

FIG. 31 is an explanatory diagram showing how to measure a convex portion.

32 is a diagram showing an endoscopic image corresponding to FIG. 31. FIG.

33 to 38 relate to a fifth embodiment of the present invention, and FIG. 33 is an overall configuration diagram of an endoscope apparatus of the fifth embodiment.

FIG. 34 is a cross-sectional view showing the structure on the distal end side of the endoscope.

35 is a front view of the glass plate viewed from the front direction of FIG. 34.

36 (A) is an explanatory view showing a state where a line-shaped shadow is projected on the inner surface of a pipe having a recessed portion, and FIG. 36 (B) is an enlarged view of a part of FIG. 36 (A).

37 is an explanatory diagram showing a captured image corresponding to FIG. 36 (A).

FIG. 38 is a view showing a projection plane passing through a recess cut along a projection line of a shadow.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Endoscope device 2 ... Electronic endoscope 3 ... Illumination light source 4 ... Measuring unit 5 ... Laser light source 6 ... Insertion part 7 ... Operation part 8 ... Universal cord 9 ... Electric cable 11 ... Tip part 14 ... Illumination window 15 ... object plane 16 ... observation window 17 ... objective lens system 18 ... CCD 19 ... imaging unit 22 ... laser line projection unit 23 ... optical fiber 24 ... laser line projection lens system 35 ... CCU 36 ... frame memory 37 ... CRT 38 ... CPU 40 ... Keyboard 41a, 41b ... Laser line 53 ... Laser light source unit 56 ... Laser diode

Claims (1)

[Claims] 1. An elongated optical insertion part, an illumination optical system provided on the distal end side of the insertion part for emitting illumination light to an object, and an objective optical system forming an image of the object illuminated by the illumination light. And an internal view including a reference line projection unit that projects a reference line that passes through a concave portion or a convex portion that is a measurement target that exists on the surface of the target object, and an image sensor that photoelectrically converts an image based on the objective optical system. A mirror, signal processing means for performing signal processing on the image sensor to generate a video signal, and a display for displaying an image corresponding to the object on which the reference line is superimposed by inputting the video signal. Means, a position designating means for designating an arbitrary position of the image, and a reference line passing through the surface is regarded as a reference line for measurement, and an approximate line that three-dimensionally represents the reference line. A calculation equation 3 corresponding to the point specified by the position specifying means on the reference line passing through the recesses or protrusions
An endoscope apparatus comprising: a calculation unit that calculates a dimensional coordinate position and calculates a distance between the approximate line and the three-dimensional coordinate position to calculate a depth of the concave portion or a height of the convex portion.