JP3093875B2 - Stereoscopic endoscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereoscopic endoscope for obtaining an object having parallax and enabling stereoscopic observation.

[0002]

2. Description of the Related Art In recent years, by inserting an elongated insertion portion into a body cavity, it is possible to observe an organ in the body cavity, and if necessary,
2. Description of the Related Art An endoscope capable of performing various medical treatments using a treatment tool inserted into a treatment tool channel is widely used. In addition, industrial endoscopes are widely used for observing and inspecting internal scratches and corrosion of pipes of boilers, gas turbine engines, chemical plants, etc., bodies of automobile engines, and the like.

The endoscope has a flexible insertion portion, and is inserted through a body cavity bent from the mouth or the like to observe an affected part in the body cavity.
Alternatively, there is a flexible endoscope that can be diagnosed. Further, as the endoscope, there is a rigid endoscope in which an insertion portion is rigid and is linearly inserted toward a target portion.

In the case of the optical endoscope, a flexible image guide fiber is used as the flexible endoscope, and this fiber is used as an image transmitting means.

In addition, the rigid endoscope has a rigid insertion portion, so that it has excellent snipering properties and obtains an optical image by using a relay optical system as an image transmitting means. .

Further, endoscopes including rigid endoscopes include those for directly observing an optical image with the naked eye and those for a charge-coupled device (CC).
A device using a solid-state imaging device such as D) as an imaging means has been proposed.

[0007] Most of the above-mentioned endoscopes generally view an object to be inspected, for example, the inside of a body cavity as a plane without perspective. However, it has been difficult for conventional endoscopes to observe minute irregularities, which are very important as diagnostic indices, for example, on the inner wall surface of a body cavity. To cope with this, a stereoscopic endoscope has been proposed. For example, Japanese Patent Laying-Open No. 57-69839 discloses an image guide in which an objective lens is provided at each end of a pair of image guides and an eyepiece is provided at the other end. In this stereoscopic endoscope, the two image guides are installed as a pair in an endoscope insertion portion so that the angle of convergence between the pair of objective lenses and the observation target point is set to an angle capable of stereoscopic viewing. Thus, the inside of the body cavity can be observed three-dimensionally.

The above conventional stereoscopic endoscope is an example applied to a flexible endoscope. As a stereoscopic rigid endoscope, two relay optical systems are arranged in parallel, and two relay optical systems are arranged. Some systems capture an optical image obtained by a system using a CCD or the like and enable three-dimensional observation. Also, U.S. Pat.
Japanese Patent Application Publication No. 35-35300 discloses an apparatus which includes two light transmission means and two shutters, and alternately shields two light images obtained by these light transmission means with shutters to enable stereoscopic observation. I have.

As described above, the stereoscopic endoscope provides the left and right optical images having parallax to the observer. While some observers obtain a three-dimensional effect by observing (directly) with the naked eye through special glasses, there are also devices that display left and right subject images on a monitor so that they can be observed as a three-dimensional image. .

In this device, an optical image of a stereoscopic endoscope is converted into an electric signal by an image pickup means, and the electric signal is processed and displayed on a monitor. There are two types of display, one displaying the left and right images simultaneously and the other displaying the images alternately.

In any of the display methods, the left and right images of the object located at the center on the observation image screen match the object image viewed through the glasses on the screen, thereby providing an easy-to-view three-dimensional effect. Observed as an image.

[0012]

In a conventional stereoscopic endoscope, an image having parallax is obtained using two optical systems. Therefore, in the conventional stereoscopic endoscope, a difference between the left image and the right image occurs due to a difference between the two optical systems, for example, a difference in magnification, an aberration, a deviation of an optical axis, and the like. This gap is
For example, it appears as a displacement of the display position on the monitor or a difference in the shape of the image itself, unlike the originally obtained image.

[0013] Since the left image and the right image have parallax, if there is a shift in the outline or the like, and if the shift amount of the display position of the left and right images is within an appropriate range, the observer will be able to see the matched image. It can be observed as a three-dimensional image without discomfort (without feeling as separate images). That is, it can be recognized as one stereoscopic image. However, if the shift amount of the display position is too large, the images are not united and the image is blurred (blurred). At this time, the observer not only cannot recognize the image three-dimensionally but also feels very tired.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and a stereoscopic vision which can reduce the difference between two subject images having parallax to obtain an optimal stereoscopic effect and reduce the fatigue of the observer. It is intended to provide an endoscope device.

[0015]

SUMMARY OF THE INVENTION A stereoscopic endoscope according to the present invention includes a color filter that transmits reflected light from a subject in a plurality of different colors as an optical image having parallax, and a color filter that transmits the color filter. A plurality of color optical images, optical combining means for optically combining so as to pass through the same optical axis, and a light transmitting means for transmitting the plurality of color optical images through the optical combining means,
A separation unit configured to separate the plurality of color optical images transmitted by the light transmission unit, and an imaging unit configured to input the plurality of color optical images separated by the separation unit and convert the plurality of color optical images into electric signals. .

[0016]

According to the present invention, the plurality of color optical images transmitted through the color filter are optically combined by the optical combining means so as to pass through the same optical axis, and the plurality of color optical images are transmitted by the light transmitting means. Means for reducing the difference between the plurality of color optical images.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 relates to a first embodiment of the present invention. FIG. 1 (a) is a configuration diagram of a stereoscopic rigid endoscope, and FIG. 1 (b) is a color rotation filter. In describing the stereoscopic endoscope of the present embodiment, a rigid endoscope will be described as an example.

The stereoscopic rigid endoscope 1 shown in FIG.
It has two objective lenses and one relay optical system so that left and right subject images having parallax can be obtained for stereoscopic observation. This stereoscopic rigid endoscope 1
Includes a rigid insertion portion 2 and a large-diameter operation holding portion 3 connected to the insertion portion 2. The operation holding unit 3 includes:
The cable 4 extends rearward.

The rigid stereoscopic endoscope 1 is electrically connected to a control device (not shown) via a cable 4. The control device supplies illumination light to the illumination optical system. Then, the stereoscopic rigid endoscope 1
Is provided with an illumination optical system (not shown), and illuminates the subject with illumination light from the control device.

The insertion section 46 has a color rotation filter 5 and left and right objective lenses 6a and 6b composed of a plurality of lenses in this order from the front end side. A stop is provided between the objective lenses 6a and 6b. 7a and 7b are interposed.

As shown in FIG. 1B, the color rotation filter 5 includes circular filters 5r, 5g and 5b that transmit red (R), green (G) and blue (B) colors. I have. The color rotation filter 5 is configured to rotate about an axis by rotation means (not shown). Filters 5r, 5
g and 5b are equally 12 around the axis of the color rotation filter 5.
It is arranged at 0 degrees.

The objective lenses 6a and 6b are arranged at 120 degrees to the center axis of the color rotation filter 5, and the filters 5r and
5g and 5b are arranged such that any two of them face each other. Further, the objective lens 6a and the aperture 7
a, the objective lens 6b, and the aperture 7b are arranged obliquely inward so that the extension of the optical axis intersects the insertion section 2 at a predetermined distance. The intersection of the extension of the optical axis is hereinafter referred to as an object point.

The objective lenses 6a and 6b apply light coming from an object point to the filters 5r and 5r of the color rotation filter 5.
g or 5b, any two of which are transmitted and enter as a color subject image. This color rotation filter 5
Rotates, light of two colors of red, green and blue enters the objective lenses 6a and 6b and changes sequentially according to the rotation.

The insertion section 2 includes reflection mirrors 8a and 8b as optical combining means for optically combining color subject images transmitted through the color rotation filter 5 so as to pass through the same optical axis.
And a combining prism 9. Reflection mirror 8a,
Reference numerals 8b are arranged behind the objective lenses 6a and 6b, respectively, and are arranged so as to reflect light from the objective lenses 6a and 6b toward the left and right sides of the combining prism 9, respectively. This combining prism 9 is, for example, a combination of two triangular prisms. The reflected light from the reflection mirror 8a incident on one triangular prism is reflected by the one triangular prism, passes through the boundary surface between the two prisms, and travels along the optical axis coincident with the central axis of the color rotation filter 5. And go backwards. The reflected light from the reflection mirror 8b that has entered the other triangular prism is reflected at the boundary surface between the two prisms, and travels backward along the optical axis.

The insertion section 2 has one relay optical system 10 for simultaneously transmitting two color subject images synthesized by the synthesizing prism 9 so that the optical axes coincide with each other.

The operation gripping part 3 has a relay optical system 10
A three-color separation prism 11 is disposed as a separation unit that separates the two color subject images transmitted by. The three-color separation prism 11 converts the light from the relay optical system 10 into red,
It separates the light into green and blue light. The three-color separation prism 11 includes, among the light from the relay optical system 10,
A first reflecting surface that reflects only blue light and transmits the other,
And a second reflection surface that reflects only green of the red and green light transmitted through the reflection surface and transmits red as it is.

Three CCDs 12r, 12g, and 12g as image pickup means for independently receiving object images of red, green, and blue respectively separated by the three-color separation prism 11 and converting them into electric signals. b is arranged. For these red,
The green and blue CCDs 12r, g, and b are separated red,
It is arranged on the green and blue optical axes, and captures a subject image of each color. The electric signals output by the CCDs 12r, g, and b are output to a control device (not shown) via the cable 4.

The CCDs 12r, g, and b take color object images having parallax two by two and output them sequentially. The controller processes the electrical signals output from the two CCDs 12r, g, and b simultaneously, and a monitor (not shown) displays the processed signals as a three-dimensional color subject image.

The control device includes a CCD 12r,
In addition to driving g and b, the output electric signal is signal-processed, and two color subject images having parallax are alternately displayed on the monitor, for example, 30 times a second. The observer can observe the subject image displayed on the monitor as a stereoscopic image through the light-shielding glasses. The light-shielding glasses are configured to alternately shield the left and right in synchronization with the display image. This is to give the observer a three-dimensional effect by using the afterimage phenomenon, and the objective lens 7a,
Since the two subject images obtained by 7b have parallax, they can be observed as a three-dimensional image.

With the above configuration, the color rotation filter 5 is rotated, and any two of red, green and blue are opposed to the objective lenses 6a and 6b, and two color subject images at that time are obtained. This is repeated in accordance with the rotation of the color rotation filter 5, so that two color subject images can be obtained at the same time and can be obtained in a time-series manner. Table 1 shows the relationship between the color subject images obtained by the filter and the CCD and the left and right images.

[0031]

[Table 1] As shown in Table 1, when a red subject image enters the objective lens 6a, a green subject image enters the objective lens 6b. Next, the color rotation filter 5 is rotated and the objective lens 6 is rotated.
When a green subject image is incident on a, a blue subject image is incident on the objective lens 6b. Further, when the color rotation filter 5 rotates and a blue subject image enters the objective lens 6a, a red subject image enters the objective lens 6b.

The CCDs r, g, b are connected to an objective lens 6
A subject image of each color obtained through one of a and 6b is captured. The imaging and reading timings of the CCDs r, g, and b are controlled by the control device and synchronized with the rotation timing of the color rotation filter 5 under the control of the control device.

The control device has, for example, six frame memories (not shown), and sequentially stores output signals picked up by each CCD in the six frame memories via selectors (not shown). The video signals stored in the six frame memories are converted into the left video signal (subject image) by synchronizing the left R, G, B color signals by the control device, and the right R, G, B Are synchronized to form a right video signal (subject image). On the monitor, the right subject image is displayed for the right eye, while the left subject image is displayed for the left eye. The observer, through the shading glasses,
A three-dimensional subject image can be observed.

In this embodiment, when transmitting the left and right images,
Since only one relay optical system is used, the difference between the left and right images can be smaller than that using two optical systems. Therefore, the balance between the left and right images is good, the displacement of the display position on the monitor is small, and the observer can easily view and can perform three-dimensional observation with less fatigue.

As a method for realizing stereoscopic vision, a method for simultaneously displaying left and right images on the same monitor as described above may be used, as well as a method for simultaneously displaying the left and right images. Also, the present embodiment
The present invention can be applied not only to a stereoscopic rigid endoscope but also to a soft stereoscopic endoscope using a flexible image guide fiber instead of a relay optical system as a light transmitting means.

FIG. 2 relates to a second embodiment of the present invention.
2A is a configuration diagram of a stereoscopic rigid endoscope, and FIG. 2B is a configuration diagram of a color rotation filter.

In this embodiment, in addition to the configuration of the first embodiment,
It has a third objective lens 6c, a third stop 7c, and a third reflection mirror 8c, and is configured to simultaneously capture red, green, and blue color subject images. In addition, the same components as those of the first embodiment are denoted by the same reference numerals and the description thereof will be omitted, and only different points will be described.

A rigid stereoscopic endoscope 14 shown in FIG.
Are objective lenses 6a, 6c, 6c so as to face three filters of the color rotation filter 5 shown in FIG.
Are uniformly arranged at 120 degrees to the center axis.

The objective lens 6c and the aperture 7c are directed inward so that the extension lines of the optical axes of the objective lenses 6a and 6b and the apertures 7a and 7b intersect at a predetermined distance in front of the insertion section 2. Are arranged diagonally. The intersection of the extension of the optical axis is hereinafter referred to as an object point.

The objective lenses 6a, 6b, 6c are provided with filters 5r, 5g, 5 of the rotating color rotation filter 5.
Each of the color subject images transmitted through any of b is incident.

As the optical synthesizing means, the reflection mirror 8 is used.
a, 8b, 8c and an optical path combining triangular prism 15 are provided. The reflecting mirrors 8a, 8b, 8c are disposed behind the objective lenses 6a, 6b, 6c, respectively, and are directed toward the optical path combining triangular prism 15 to the objective lenses 6a, 6b, 6c.
The light from c is arranged to reflect each.

The optical path synthesizing triangular prism 15 synthesizes the respective color subject images reflected by the reflecting mirrors 8a, 8b, 8c so that the optical axes of the respective color subject images coincide, and the relay optical system 10 simultaneously transmits three color subject images. It is supposed to.

The red, green, and blue CCDs 12r, g,
b captures the color subject image transmitted by the relay optical system 10, respectively.

In this embodiment, as in the first embodiment, signal processing and display can be performed. However, the image obtained by the objective lens 6c and the image obtained by the other objective lens 6a or 6b can be used. In the same manner, similar signal processing and display can be performed. That is, stereoscopic observation is possible not only in the left-right direction but also in other (two) directions. This observation may be switched and displayed on one monitor.

Alternatively, two or three monitors may be provided and displayed simultaneously. When displaying a plurality of stereoscopic images, an additional configuration such as the frame memory is required. The other configuration and operation and effect are the same as those of the first embodiment, and the description is omitted.

FIG. 3 is a configuration diagram of a stereoscopic rigid endoscope according to a third embodiment of the present invention. In the present embodiment, instead of the color rotation filter 5 of the first embodiment, a fixed color filter 17a,
17b is provided, while the CCD 12g is omitted. Other configurations and operations are the same as those of the first embodiment, and thus the same reference numerals are given and the description is omitted.

The color filter 17a shown in FIG. 3 is a red filter, and the color filter 17b is a blue filter.
The CCDs 12r and 12b capture red and blue subject images, respectively.

In this embodiment, a red subject image having parallax and a blue subject image are obtained. If these images are displayed simultaneously (or alternately), a subject image having a three-dimensional effect can be obtained. it can. However, it is not a color image but a red and blue subject image.

The present embodiment has an advantage that the processing circuit on the control device side can have a simple configuration. The difference between the left and right images can be reduced as in the first embodiment. The other configuration and operation and effect are the same as those of the first embodiment, and the description is omitted.

[0050]

As described above, according to the stereoscopic endoscope of the present invention, the difference between two subject images having parallax can be reduced, so that an optimal stereoscopic effect can be obtained and the fatigue of the observer can be obtained. There is an effect that the feeling can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a stereoscopic rigid endoscope and a color rotation filter according to a first embodiment.

FIG. 2 is a configuration diagram of a stereoscopic rigid endoscope and a color rotation filter according to a second embodiment.

FIG. 3 is a configuration diagram of a stereoscopic rigid endoscope according to a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Stereoscopic rigid endoscope 2 ... Insertion part 3 ... Operation holding part 5 ... Objective lens 6a, 6b ... Objective lens 7a, 7b ... Stop 8a, 8b ... Reflection mirror 9 ... Synthetic prism 10 ... Relay optical system 11 ... Three Color separation prism 12r, 12g, 12b ... CCD

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Susumu Takahashi 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside O-Limpus Optical Co., Ltd. (72) Inventor Akihiko Mochida 2-34-2 Hatagaya, Shibuya-ku, Tokyo Inside the Olympus Optical Co., Ltd. (72) Takashi Fukaya, Inventor 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside the Olympus Optical Co., Ltd. Toshihiko Hashiguchi 2-43-2, Hatagaya, Shibuya-ku, Tokyo Inside the Olympus Optical Co., Ltd. (72) Kenji Yoshino 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside the Olympus Optical Co., Ltd. Hitoshi Karasawa 2-43-2 Hatagaya, Shibuya-ku, Tokyo (72) Inventor Keisuke Saito 2-43-2 Hatagaya, Shibuya-ku, Tokyo O-limpus Optical Co., Ltd. (56) References JP-A-4-16812 (JP, A) JP-A-1-185240 (JP, A) JP-A-2-124132 (JP, A) (58) Fields studied (Int .Cl. ⁷ , DB name) G02B 23/24 A61B 1/00 A61B 1/00 300 G02B 23/26

Claims (1)

(57) [Claims] 1. A color filter that transmits reflected light from a subject in a plurality of different colors as optical images having parallax, and a plurality of color optical images transmitted through the color filters pass through the same optical axis. Optical synthesizing means for optically synthesizing, light transmitting means for transmitting a plurality of color optical images having passed through the optical synthesizing means, separation for separating the plurality of color optical images transmitted by the light transmitting means, respectively A stereoscopic endoscope comprising: a unit; and an imaging unit that receives the plurality of color optical images separated by the separation unit and converts the image into an electric signal.