JPS59187310A - Internal observation device - Google Patents

Abstract

PURPOSE:To calculate the ruggedness of an object by irradiating one point of the object with light in a spot, knowing the positions of the spot in an observed picture at two observation points, and calculating three-dimensional coordinates of the spot. CONSTITUTION:The irradiation light from an optical fiber 3 is reflected by a scanning mirror 8 to scan on the object 9 as the spot 9, and fixed mirrors of image fibers 1 and 2 shift in position axially; and an image of an P with parallax corresponding distance l is transmitted to the fibers 1 and 2 and inputted to TV cameras 35 and 36 through image forming lenses 31 and 32 to display spots P(x1, y1) and P(x2, y2) on TV monitors 39 and 40. Interfaces 41 and 42, on the other hand, process them which are inputted to a CPU45. Scanning timing information on a mirror driving unit 43 is supplied to the CPU45 through an interface 44 to calculate coordinates (x), (y), and (h) of the spot P of the object 9 from pieces of spot position information from the image fibers 1 and 2 and the timing information from the unit 43.

Description

Detailed Description of the Invention (7) Technical Field The present invention relates to an apparatus for observing the inside of a narrow area, such as inside a human organ such as a blood vessel or a heart, or inside a pipe for gas or water.

(a) Prior art and its problems Internal observation devices using image fibers are used for medical and industrial purposes. In order to directly observe a narrow area, a long flexible cable with an image fiber and light guide inserted into a flexible tube is inserted near the observation area.

The illumination light is transmitted inside by the light guide and illuminates the object. An image of the object is formed on the end face of the image fiber by a lens system. This image is transmitted by an image fiber.

The end of the internal observation device that is close to the object is called an imaging section. On the other hand, the end on the observer's hand side is called the image receiving section. The intermediate part is called the transmission section.

FIG. 11 is a schematic cross-sectional view showing a state in which the imaging section of a conventional endoscope is inserted into the heart.

Endoscope flexible cable 52 into the heart 51
The tip is inserted. The flexible cable 52 includes an image fiber 53, five light guides, and an injection tube 5.
5 are bundled and placed into a single flexible tube.

The image of the image fiber 53 is viewed directly by, for example, the naked eye 56 at the image receiving section. The image of the image fiber 53 may be projected onto a television screen using a TV camera or the like.

An illumination light source 57 is provided at the other end of the light guide 54.

At the other end of the injection liquid tube 55, an injection liquid syringe 58 for injecting a transparent liquid is installed.

Since blood is opaque, a transparent liquid is injected into the heart 51 to instantly open the visual field.

The light from the light guide 54 illuminates the inner wall of the heart, and at this moment the image fiber 53 transmits an image of the inner wall to the image receiving section. Observe with the naked eye or with a TV camera at the image receiving section.

In this example, the endoscope was inserted into the heart, which was filled with opaque fluid, so clear fluid had to be squirted out.

However, if the object to be observed is narrow and not filled with opaque liquid, an injection tube, syringe, etc. are not necessary. In this case, the endoscope is an image fiber and
Use a flexible cable that includes a light guide holder.

With such an internal observation device, a narrow area can be enlarged and observed as a clear image. Extremely useful.

However, such an internal observation device observes a three-dimensional space as a two-dimensional image. I can't see the unevenness of the observation target. The various organs of the human body differ not only in shape and hue, but also in elevation,
It is desirable to be able to accurately detect the presence of irregularities such as depressions.

Even when observing the inside of gas or water pipes, it is useful to know the condition of the unevenness of the inner wall.

Conventional endoscopic devices cannot detect the unevenness of an object. This is because there is only one image fiber and one observation point.

The present invention provides an internal observation device that determines the unevenness of an object.

(1) Internal observation device of the present invention The internal observation device of the present invention can view the same target point from two observation points and know in what direction the same target point is located from the two observation points. Then, calculate the three-dimensional position of the target point. Here, we irradiate light onto one point on the object,
Gives a spot of light. Knowing the position that this spot occupies in the images observed at the two observation points,
It calculates the three-dimensional coordinates of the spot.

In conventional internal observation devices, the light diffuses over a wide angle and illuminates the object widely and uniformly. In the present invention,
The illumination light does not illuminate the object widely. It only gives a small spot. This spot is 2
It provides the goal of simultaneously observing the same target point from two observation points.

Additionally, the spot of light scans over the object.

The spots scan the entire area of the object to be observed, and the three-dimensional position of each spot is calculated. In this way, the unevenness of the object can be known.

For example, a mirror can be used to scan the spot of light. If the mirror is rotated back and forth at high speed, the axis of rotation is gradually tilted, and the illumination light is reflected by the mirror, the spot of light can be scanned two-dimensionally over the object. The mechanism for displacing the mirror can be wire drive, hydraulic drive, or the like.

In addition to this, a prism or a lens can also be used as the light spot 74 mechanism.

Furthermore, if it is permissible to apply a voltage to the imaging section of the internal observation device, a light deflection device that utilizes the electro-optic effect can be used.

The internal observation device of the present invention includes (1) an optical fiber that transmits illumination light, (2) a mechanism that focuses the light from the optical fiber onto an observation target and scans it, and (3) a mechanism that transmits the light from two parts separated from each other. A means for forming an image on the end face of the image fiber as seen from the direction (4), two image fibers (5), and a means for calculating the height of the object to be observed from the difference between the images transmitted by the image fibers.

(b) Calculation for calculating height According to FIG. 8, 8 for calculating height h in the present invention.
1 Derive the formula.

Observation point A! Set it to 3. Let M be the midpoint of base line AB.

Take an xy plane along the axis of the observation target. Let O be the origin. The xy plane only needs to be close to the surface of the object, and it is not strictly necessary that the curved surface of the object be in contact with the xy plane.

Assume that the spot of light is at point P. We want to find the height h of the xy plane of point P as a function of the X%V coordinate of point P. The base JAB and the X axis are parallel.

The h-axis is a straight line that is perpendicular to the xy plane and passes through the midpoint 1v1 of the 8th observation point. Let d be the distance between the origin 0 and the base line center IVi.

Let E and F be the intersections of the straight line P, an extension of BP beyond P, and the xy plane.

Point E is the projection point of P onto the xy plane when Spora) P is viewed from observation point A. Let the coordinates of E be (Xi, yl). If the distance d is known, the straight line AE is AS,Q
Since we know the angle made by i%/i etc., we can calculate the coordinates (xl, yx)
is also uniquely determined.

Point F is the projection point of P onto the xy plane when Spora) P is viewed from observation point B. Let the coordinates of F be (x2, Y2).

Let Q and R be the legs of the perpendicular line drawn from spot P to the xh plane and the Xy plane. Let S be the foot of the perpendicular line drawn from P to the X axis. Let the foot of the perpendicular line drawn from P to the y-axis be the bottom.

T Q = X S P Q = y% Q S =
It is h. The coordinates of point R are (XXV). Observation point A
Let the interval between U be l. Let H and G be the intersection points of the X axis and straight line AQ and straight line BQ, respectively. HaIVI, BiVl (J
/2.

Drop perpendicular lines from observation points A and B to the X-axis, and let that foot be UXW.

In triangle HAU, QS and AU are parallel.

AU is equal to d and QS is equal to h. H5 is (xl-
x) and HU is (Xl + l/2). From the proportional relationship of triangles, it is XI + (J/ 2 d).

Similarly, from the proportional relationship in triangle EAH, Vx
It is d.

Focusing on triangle GBW, β/2 X2 d. From the proportional relationship of triangle FBG, y2 V
hV2
It is d.

When calculating X5ysh from (1) to (4), it becomes. y
It is ly2. This is because xlitfi is made parallel to the baseline.

In this way, from the coordinates of the projection points E and F, P (X
The height h at the point (N, -y) can be found.

However, the coordinates x1 and x2 that indicate point E1F are calculated based on the assumption that the observer is actually at points A and F3.
This is the value obtained by projecting . For the observer on day A1, the xy plane, which is the origin 0, is not immediately identified.

Rather, for the observer at point A, the xy plane with the origin as U should be viewed directly. If Ax is the coordinate (only the X coordinate) of point F that can be recognized by an observer of the point F with respect to the origin, then β Ax = xl + - (8). Observers at 8 points view the xy plane with W as the origin. In such a coordinate system, the X coordinate Bx of point F is Bx = X2- (9).

In this way, the X coordinate of the projection point, Ax-, based on the observation point A1 day, is given by , where Xs V% h is expressed on day X.

HAx's YIS sx % 3/2 is a value that can be easily known by an observer at observation point A>8.

When the object is completely flat and overlaps the xy plane, Ax −
ax = β.

In these relational expressions, l is a predetermined quantity. d
cannot be considered as a predetermined quantity. The optical system that guides the illumination light that provides the spot uses a lens to connect a small spot on a surface at a certain distance. Lenses are fixed and may not be adjustable.

When a fixed lens system is used, there is only one point where the light spot becomes the minimum, and the distance from the midpoint M of the baseline at the time of focusing to the spot is equal to d.

In this way, observation point A1 is placed at the position where the spot diameter is minimum.
By setting the midpoint M, d can take a predetermined value.

However, there are cases where it is not always possible to match the position of the imaging section including the image fiber to the position at the distance d from the object.

In this case, the vertical distance d can be determined by giving the ray direction of the illumination light.

For example, assume that illumination light is emitted from the midpoint of the baseline.

If the three parameters of the emission direction 11/i P from this point and the observation directions AP, BP from the 8 points are determined simultaneously, the vertical distance d can be calculated backwards.

Care must be taken regarding distance 4 from observation point AB.

When the end face of the image fiber is on day A1, the image fiber end face spacing is equal to 4.

However, by using a mirror, the light is reflected and this becomes the correct position.

Examples) The present invention will be explained below with reference to drawings showing examples.

FIG. 1 is a schematic perspective view of the tip of the imaging unit of an internal observation device according to an embodiment of the present invention, FIG. 2 is a longitudinal cross-sectional view of the same, and FIG. .

The internal observation device includes two image fibers 1.2 and
Optical fibers 3 for illumination light transmission are housed in a bundle in a casing 4.

A transparent observation window 5 is provided on the side near the tips of the two image fibers 1.2 and the optical fiber 3.

A fixed mirror 6.1 is provided apart from the end faces of the two image fibers 1.2 and on an extension of the optical axis. The fixed mirror 6.7 reflects the light entering from the side observation window 5 and makes it enter the image fiber 1.2.

A scanning mirror 8 is provided apart from the end face of the optical fiber 3 for transmitting illumination light and on an extension of the optical axis.

The illumination light is emitted from the end face of the optical fiber 3, reflected by the scanning mirror, and illuminates the object 9. Unlike the case of a normal endoscope, the illumination light does not illuminate the target 9 widely, but illuminates only one spot as a small light spot P.

The scanning mirror 8 causes the spora) P to scan in the horizontal direction.

A mirror drive unit 10 rotates the scanning mirror 8 left and right.

FIG. 4 is a sectional view of the tip of the image fiber 1.2. FIG. 5 shows a sectional view taken along the line ■-■ in FIG.

At the tip of the image fiber 1.2, there is a microlens 1.
1 is fixed by a lens sleeve 12. The image fiber 1.2 consists of an image fiber body 15, which is a bundle of a number of fibers that transmit images, and a coating 14 that covers this body.

A part of the coating 14 on the tip of the image fiber 1.2 is peeled off, and the image fiber 1.2 is inserted into the lens sleeve 12 and bonded with an adhesive 13.

The microlens 11 forms an image of the spot P on the end face 16 of the image fiber.

Optical fiber 3 also has a lens on the end face, and illuminates the spot)
I try to focus it on P. Figure 6 shows optical fiber 3
FIG. FIG. 7 is a sectional view taken along the line ■-■ in FIG. 6.

The optical fiber 3 includes a fiber body 17 and a coating 18 for transmitting light. A quartz glass or plastic optical fiber can be used for this purpose.

Part of the coating 18 on the tip of the optical fiber 3 is peeled off, and a lens sleeve 19 is adhered with an adhesive 21. At the front of the sleeve 9, a microlens 20 is attached to an adhesive 21.
glued by.

An image of the end surface 22 of the optical fiber 3 is formed by the microlens 20 as a spon (P) of the object 9. Since the length of the optical path from the optical fiber 3 to the target 9 via the mirror 8 is determined by the focal length of the lens 20, the optimum distance from the mirror 8 to the spot P is determined in advance.

It is convenient to use this as the parameter d in the above equation.

FIG. 9 is a perspective view showing the scanning mirror and the scanning line of spot P.

Let the plane on which the target 9 exists be the xy plane. The scanning mirror 8 is rotated left and right about the V-axis by a mirror drive unit 10. The illumination light 25 is reflected by a mirror and x
spot on the y plane) converges to P.

One movement of the mirror around the V-axis results in one scan in the X-axis direction of the xy plane. The mirror 8 is tilted around the W axis, and along with this,
The scanning line shifts in the y-axis direction.

A well-known scanning method can be used.

The drive unit 10 of the scanning mirror 8 is controlled from the outside using a drive cable 24 or a hydraulic mechanism.

FIG. 10 is an overall view of the internal observation device of the present invention.

The light from the illumination light source 34 is focused by the condenser lens 33 and enters the illumination light optical fiber 3. The illumination light is reflected from the optical fiber 3 by the scanning mirror 8 and scans over the object 9 as a spot P.

The fixed mirror of the image fiber 1.2 is, as mentioned above, offset in the axial direction, and an image of the spot P with a parallax corresponding to the distance l is transmitted to the image fiber 1.2. The image appearing on the image-receiving side end surface is formed by the imaging lens 31.3.
2 to the TV right camera 5.36.

On the other hand, the image input to the TV right camera 5.36 is
Spot P (xl, yl) on TV monitor 39.40
, P(X2, Y2).

The image information input to the TV right camera 5.36 is serial/parallel converted at the interface 41.42.
After analog/digital conversion and other processing, C
It is input to PU45.

The mirror drive unit) 43 drives the scanning mirror,
Scanning timing information of the mirror drive unit 43 is provided to the CPU 45 through an interface 44 .

Spot position information (xx,
yx), (X2, V2) and the timing information from the mirror drive unit 43, the coordinates X%V%h of the spot P on the target 9 are calculated.

In particular, it is convenient to calculate the height h as a function of XXV.

The stereoscopic display device 47 displays the height h as a function of (xly) on the screen based on the calculation result of the CPU 45.

(tJ) Effects The internal observation device of the present invention applies a small spot to the object, observes it from two points, and calculates the unevenness of the object from the shift of the spot image.

When used as a medical endoscope, the unevenness of the inner walls of human organs can be calculated. Since it is not only possible to recognize two-dimensional hues and shapes, but also to make three-dimensional observations, useful diagnostic materials can be provided.

It can also be usefully used for industrial purposes and for internal observation of narrow gas pipes and water pipes.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view of an imaging section of an internal observation device according to an embodiment of the present invention. Figure 2 is a longitudinal sectional view of the same thing. FIG. 3 is a llll-1 sectional view in FIG. 2. FIG. 4 is a partially longitudinal side view of the tip of the image fiber. FIG. 5 is a sectional view taken along the line ■-■ in FIG. 4. FIG. 6 is a partially vertical side view of the tip of an optical fiber for transmitting illumination light. FIG. 7 is a sectional view taken along the line ■-■ in FIG. 6. FIG. 8 is an explanatory diagram for looking at spot P from two observation points AXB and deriving the coordinates X and yzh of the spot from the coordinates of projection points E and F. FIG. 9 is an explanatory perspective view showing the relationship between the scanning mirror and the scanning movement of the spot. FIG. 10 is an overall configuration diagram of the internal observation device of the present invention. FIG. 11 is a cross-sectional view showing a state in which the heart is observed with a conventional endoscope device. L2... Image fiber 3...
...... Optical fiber 4... Casing 5...
・・・・・・ Observation window 6,
7 ・・・ ・・・ Fixed Mira
-8 ・・・ ・・・ ・・・ Run
Incense Mira -9・・・・・・・・・・・・
Target 10... Mirror drive unit 11... Micro lens 12...
・・・・・・ Lens sleeve 13・・・・・・・・・
Adhesive 14...... Covered
Memory 15... Image fiber body 16... End surface 17.
...... Optical fiber body 18...
...Coating 19... Lens sleeve 20... Microlens 21
...... Adhesive 22...
...... End surface 24...
... Drive cable 33 ...... Condensing lens 34 ...... Light source 1 for illumination light 421 ... Interface 4 43 - ...... Mirror Drive unit 45・
...... CPU 47 ...... Stereoscopic display device P ...
... Spots A and B where the illumination light converged...
・・・ Observation point l ・・・・・・・・・
Distance between observation points Inventor Toshiokichi Utsunomiya 1) Ken - Kimi Ono Hiroshi Mitsuno - Mitsuru Nishikawa Patent applicant Sumitomo Electric Industries, Ltd.

Claims (3)

[Claims] (1) An optical fiber that transmits illumination light, a mechanism that forms an image of the light from the optical fiber on the observation target as a spora) and scans it, two image fibers, and a spora of the above light. ) P is characterized by comprising means for forming an image of a potential spot on the end face of the image fiber from two directions separated from each other, and means for calculating the height of the observation target from the position of each image fiber transmitted image. Internal observation device. (2) The two image fiber end faces are spaced apart in the axial direction of the image fiber, and the light from the observation target on the side of the image fiber is reflected by a fixed mirror to form an image on the image fiber end face. An internal observation device according to claim (1). (3) The internal observation device according to claim (1), wherein the mechanism for scanning the illumination light comprises a reflecting mirror and a driving mechanism thereof.