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Claims  |
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What is claimed is:
1. A stereo endoscope apparatus comprising:
an elongated insertion portion;
first and second optical guide means inserted into said insertion portion,
and through which an optical image can be transmitted;
a lens system for imaging said optical image at each front end surface of
said first and second optical guides disposed at the front end of said
insertion portion;
light output means for outputting illuminating light to the other end
surfaces of said first and second optical guides;
imaging means for imaging said optical image transmitted to the other end
surfaces of said first and second optical guides; and
illuminating/imaging control means for introducing said optical image
transmitted through one of said guide means to said imaging means when
said illuminating light output from said light output means is supplied to
the other end of said first or second optical guide means.
2. A stereo endoscope apparatus comprising:
an elongated insertion portion;
first and second optical guide means inserted into said insertion portion,
and through which an optical image can be transmitted;
a lens system for imaging the optical image at each front end surface of
said first and second optical guides disposed at the front end of said
insertion portion;
light output means for outputting illuminating light to the other end
surfaces of said first and second optical guides;
ocular optical system means for introducing said optical image transmitted
to the other end surfaces of said first and second optical guides into two
ocular openings for observing said optical image; and
illuminating/observing control means for introducing said optical image
transmitted through either of said optical guide means to said ocular
opening which corresponds to said optical guide means when said
illuminating light is supplied to the other one of said first or second
optical guide means.
3. A stereo endoscope apparatus according to claim 1 or 2, wherein said
optical guide means comprises a fiber bundle.
4. A stereo endoscope apparatus according to claim 1 or 2, wherein said
optical guide means comprises a relay optical system in which a plurality
of lenses are longitudinally disposed.
5. A stereo endoscope apparatus according to claim 1 or 2, wherein said
optical guide means comprises a refractive index gradient type of lens.
6. A stereo endoscope apparatus according to claim 1 or 2, wherein said
light output means comprises a lamp outputting white light.
7. A stereo endoscope apparatus according to claim 1 or 2, wherein said
light output means comprises a face-successive light output means for
successively outputting light beams of a plurality of wave ranges.
8. A stereo endoscope apparatus according to claim 1 or 2, wherein said
light output means is able to selectively output said white light and said
face-successive light which successively outputs light beams of a
plurality of wave ranges.
9. A stereo endoscope apparatus according to claim 1 or 2, wherein said
light output means comprises two light source lamps.
10. A stereo endoscope apparatus according to claim 1 or 2, wherein said
light output means comprises a single light source lamp.
11. A stereo endoscope apparatus according to claim 1, wherein said imaging
means comprises an imaging optical system and an imaging element.
12. A stereo endoscope apparatus according to claim 1, wherein said imaging
means comprises two imaging optical systems and two imaging elements.
13. A stereo endoscope apparatus according to claim 1, wherein said imaging
means comprises a single imaging element.
14. A stereo endoscope apparatus according to claim 1, wherein said imaging
means comprises an imaging element provided with a color filter.
15. A stereo endoscope apparatus according to claim 1, wherein said imaging
means comprises an imaging element having no color filter.
16. A stereo endoscope apparatus according to claim 1, wherein means for
branching light is provided between said optical guide means and said
imaging means.
17. A stereo endoscope apparatus according to claim 16, wherein an image
guide is provided between said means for branching light and said imaging
element.
18. A stereo endoscope apparatus according to claim 16, wherein a light
guide is provided in such a manner that one front end surface thereof
confronts said means for branching light.
19. A stereo endoscope apparatus according to claim 1, wherein said imaging
means is detachably provided for said optical guide means.
20. A stereo endoscope apparatus according to claim 1, wherein said imaging
means is integrally formed with said optical guide means.
21. A stereo endoscope apparatus according to claim 2, wherein said ocular
optical system is integrally formed with said optical guide means.
22. A stereo endoscope apparatus according to claim 2, wherein said ocular
optical system is detachably provided for said optical guide means.
23. A stereo endoscope apparatus according to claim 2, wherein means for
branching light is provided between said optical guide means and said
imaging means.
24. A stereo endoscope apparatus according to claim 2, wherein an image
guide is provided between said means for branching light and said ocular
optical system.
25. A stereo endoscope apparatus according to claim 1, wherein said imaging
means is provided separately from said light output means.
26. A stereo endoscope apparatus according to claim 1, wherein said imaging
means is accommodated in one housing together with said light output
means.
27. A stereo endoscope system comprising:
an endoscope having an elongated insertion portion, a plurality of optical
guide means inserted into said insertion portion through each of which an
optical image can be transmitted, and a lens system for imaging an optical
image at a first end surface of each said optical guide means at the front
end of said insertion portion;
light emitting means for supplying illumination light to the other end of a
selected one of any of said optical guide means, said light being output
from said first end surface for illuminating a subject;
imaging means for making visible an optical image of the subject
transmitted to the other end surface of each said optical guide means
other than that illuminating said subject;
illuminating/imaging control means for controlling said light emitting
means and introducing said transmitted optical image from said.
28. A stereo endoscope apparatus according to claim 27, wherein said
optical guide means comprises three optical guide means.
29. A stereo endoscope apparatus according to claim 28, wherein said
optical guide means comprises two optical guide means.
30. A stereo endoscope apparatus according to claim 28, wherein said stereo
endoscope apparatus further comprises an ocular unit constituted by:
an ocular optical system which is detachably provided for said endoscope,
and which confronts said plurality of optical guide means; and
light guide means disposed confronting one of a plurality of said optical
guide means.
31. A stereo endoscope apparatus according to claim 30, wherein said ocular
unit further comprises an imaging unit constituted by:
a pair of imaging optical systems which can be fitted to said endoscope,
and which confronts a plurality of said optical guide means; and
light guide means which confronts one of a plurality of said optical guide
means.
32. A stereo endoscope apparatus according to claim 28, wherein said
optical guide means is disposed in the circumferential direction at a
uniform angle relative to the center of said insertion portion.
33. A stereo endoscope apparatus according to claim 30, wherein said ocular
unit is rotatably provided whereby a pair of said ocular optical system
confronting a plurality of said optical guide means and said light guide
means confronting one of a plurality of said optical guide means can be
replaceable.
34. A stereo endoscope apparatus according to claim 31, wherein said
imaging unit is rotatably provided, whereby a pair of said imaging optical
system confronting a plurality of said optical guide means and said light
guide means confronting one of a plurality of said optical guide means can
be replaceable.
35. A stereo endoscope apparatus according to claim 29, wherein said stereo
endoscope apparatus further comprises an ocular unit constituted by:
a pair of ocular optical systems which can be fitted to said endoscope, and
which can confront said two optical guide means; and
single light guide means which can confront said two optical guide means.
36. A stereo endoscope apparatus according to claim 29, wherein said stereo
endoscope apparatus further comprises an ocular unit constituted by:
a pair of imaging optical systems which is able to be fitted to said
endoscope, and which can confront said two optical guide means; and
single light guide means which can confront said two optical guide means.
37. A stereo endoscope apparatus according to claim 29, wherein said stereo
endoscope apparatus further comprises an ocular unit constituted by:
a pair of means for branching light which is able to be fitted to said
endoscope, and which confronts said two optical guides;
a pair of ocular optical systems which confronts one end of said means for
branching light; and
a pair of light guide means which confronts the other end of said means for
branching light.
38. A stereo endoscope apparatus according to claim 29, wherein said stereo
endoscope apparatus further comprises an imaging unit constituted by:
a pair of means for branching light which is able to be fitted to said
endoscope, and which confronts said two optical guides;
a pair of imaging optical systems which confronts one end surfaces of a
pair of said means for branching light; and
a pair of light guide means which confronts the other end surfaces of a
pair of said means for branching light.
39. A stereo endoscope apparatus according to claim 38, wherein said
imaging unit includes a signal cable extending from said imaging unit.
40. A stereo endoscope apparatus according to claim 38, wherein said
imaging unit includes no signal cable extending from said imaging unit.
41. A stereo endoscope system comprising:
an endoscope having an elongated insertion portion, first and second
optical guide means inserted into said insertion portion, and through
which an optical image can be transmitted, a lens system for imaging the
optical image at each front end surface of said first and second optical
guides disposed at the front end of said insertion portion;
light output means which can be fitted to one end portions of said first
and second optical guides of said endoscope, and which supplies
illuminating light to said end portions;
light output means for outputting illuminating light to the other end
surfaces of said first and second optical guides;
imaging means for imaging said optical image transmitted to the other end
surfaces of said first and second optical guides;
illuminating/imaging control means for introducing said optical image
transmitted through one of said optical guide means to said imaging means
when said illuminating light output from said light output means is
supplied to the other one of said first or second optical guide means;
signal processing means for generating image signals by signal-processing
the signals which have been optically converted by said imaging means; and
monitor means for color-displaying said image signals output by said signal
processing means.
42. A stereo endoscope system according to claim 41, wherein said optical
guide comprises a fiber bundle.
43. A stereo endoscope system according to claim 41, wherein said optical
guide comprises a relay optical system in which a plurality of lenses are
longitudinally disposed.
44. A stereo endoscope system according to claim 41, wherein said optical
guide comprises a refractive index gradient type of lens.
45. A stereo endoscope system according to claim 41, wherein said light
output means comprises a lamp which issues white light.
46. A stereo endoscope system according to claim 41, wherein said light
output means comprises face-successive light output means for outputting
light of a plurality of wave ranges.
47. A stereo endoscope system according to claim 41, wherein said light
output means comprises two light source lamps.
48. A stereo endoscope system according to claim 41, wherein said light
output means comprises a single light source lamp.
49. A stereo endoscope system according to claim 41, wherein said imaging
means comprises imaging elements provided with color filters.
50. A stereo endoscope system according to claim 41, wherein said imaging
means comprises imaging elements having no color filter.
51. A stereo endoscope system according to claim 41, wherein said imaging
means comprises two imaging elements.
52. A stereo endoscope system according to claim 41, wherein said imaging
means comprises a single imaging element.
53. A stereo endoscope system according to claim 41, wherein means for
branching light is provided between the other end surface of said optical
guide means and said imaging element.
54. A stereo endoscope system according to claim 53, wherein an image guide
is provided confronting one end surface of said means for branching light.
55. A stereo endoscope system according to claim 54, wherein a light guide
is provided confronting the other end surface of said means for branching
light.
56. A stereo endoscope system according to claim 41, wherein said imaging
means is provided separately from said light output means.
57. A stereo endoscope system according to claim 41, wherein said imaging
means is integrally formed with said light output means. |
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Claims |
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Description |
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BACKGROUND OF THE INVENTION
Industrial Field of the Invention and Description of the Related Art
This invention relates to a stereo endoscope apparatus which is able to
stereoscopically observe the portion to be observed.
Recently, endoscopes have been widely used for observing the coelom,
internal organs and so forth. In use, an elongated insertion portion
thereof is inserted into the coelom or the inner parts of internal organs
to observe the coelom or the internal organs, or various types of medical
treatment to be performed with the aid, if necessary, of a treatment tool
that is inserted into the treatment tool channel thereof, or to observe or
treat the inside portion of various mechanical devices.
However, the conventional endoscope can only observe the item to be
observed, for example, a coelom, in the form of a planar object, without
perspective. It therefore involves a problem in that, for example, it is
difficult to observe any slight unevenness on the surface of a coelom,
which is a very important factor as a diagnosis index. In order to solve
this problem, an art designed to observe the coelom was disclosed in
Japanese Patent Laid-Open No. 69839/1982 in which a pair of image guides
is inserted into an insertion portion of an endoscope, the image guide
having an objective lens at one end thereof and an ocular at the other end
thereof, and the convergence angle formed by the pair of the objective
lens and the subject point to be observed is made to be such that the
subject point can be observed stereoscopically. However, in this art, the
outer diameter of the insertion portion of the endoscope is made too
large, causing patients to suffer some discomfort. The outer diameter of
the endoscope is preferably as small as possible in order to reduce the
sensation of discomfort experienced by a patient and to allow the observer
to observe the isthmus of the coelom.
When any unevenness on the surface of a subject (organism) is to be
measured, a scale is used, as disclosed in Japanese Patent Publication No.
20488/1986, in such a manner that the scale is applied to the subject.
Another method is disclosed in Japanese Patent Laid-Open No. 110208/1980
in which laser beams are used.
According to the prior art disclosed in Japanese Patent Publication No.
20488/1986, since it is necessary for the subject and the scale to be
brought into contact with each other, there is potential for the organism
to be injured, and the endoscope is difficult to handle. Furthermore,
since the allowable range that can be measured is a single point, it has
been difficult to conduct wide range measurements.
On the other hand, according to the prior art disclosed in Japanese Patent
Laid-Open No. 110208/1980, it is necessary for a special apparatus such as
a laser beam to be instituted; otherwise measurement can only be conducted
in units equivalent to the distance between light spots, and sufficient
resolution cannot therefore be obtained. Furthermore, a problem arises in
that normal observation is interfered with by the laser beams.
OBJECT AND SUMMARY OF THE INVENTION
It is an object of the present invention to provide a stereo endoscope
apparatus which is able to perform a stereoscopic observation without
involving any necessity of enlarging the outer diameter thereof.
It is another object of the present invention to provide a stereo endoscope
apparatus which is suitable for use to diagonose the diseased parts.
In the present invention, at least a pair of optical guides is inserted
into the insertion portion of the apparatus, the optical guide being
capable of conducting an illuminating light and the light reflected from
the portion to be observed, whereby while either of the optical conducts
the illuminating light, the other optical guide conducts the light from
the subject observed, and the subject can be observed in a stereoscopic
manner by switching the optical guides between one state of use and.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 2 illustrate a first embodiment of the present invention,
wherein
FIG. 1 is a view illustrating the structure of a stereo endoscope
apparatus;
FIG. 2 is a timing chart illustrating the operation of the stereo endoscope
apparatus;
FIGS. 3 and 4 illustrate a second embodiment of the present invention,
wherein
FIG. 3 is a view illustrating the structure of the stereo endoscope
apparatus;
FIG. 4 is a view illustrating optical guide changing means;
FIGS. 5 and 6 illustrate a third embodiment of the present invention,
wherein
FIG. 5 is a view illustrating the structure of the stereo endoscope
apparatus;
FIG. 6 is a timing chart illustrating the operation of the stereo endoscope
apparatus;
FIG. 7 is a block diagram illustrating an essential portion of a
modification of the third embodiment;
FIG. 8 is a disposition drawing illustrating an essential portion of a
fourth embodiment;
FIG. 9 is a disposition drawing illustrating an essential portion of a
fifth embodiment;
FIG. 10 is a disposition drawing illustrating an essential portion of a
sixth embodiment;
FIG. 11 is a disposition drawing illustrating an essential portion of a
seventh embodiment;
FIG. 12 is a disposition drawing illustrating an essential portion of a
eigth embodiment;
FIG. 13 is a disposition drawing illustrating an essential portion of a
ninth embodiment;
FIG. 14 is a disposition drawing illustrating a light source unit of a
tenth embodiment;
FIG. 15 is a disposition drawing illustrating a light source unit of a
eleventh embodiment;
FIG. 16 is a perspective view of a rotatable filter according to the
eleventh embodiment;
FIG. 17 is a perspective view illustrating parts of the rotatable filter
according to the eleventh embodiment when it is being rotated;
FIGS. 18 to 21 illustrate a twelfth embodiment of the present invention,
wherein
FIG. 18 is a front elevational view of the front end portion of an
insertion portion of an endoscope;
FIG. 19 is a disposition drawing illustrating the portion in the vicinity
of the ocular unit;
FIG. 20 is a cross-sectional view taken along the line A--A' of FIG. 19;
FIG. 21 is a disposition drawing stereoscopically illustrating the portion
in the vicinity of the ocular unit;
FIG. 22 is a disposition drawing illustrating an essential portion of a
modification of a twelfth embodiment;
FIG. 23 is a view illustrating the schematic structure of a hard endoscope
for realizing stereoscopic observation using a relay optical system
according to a thirteenth embodiment of the present invention;
FIG. 24 is a view illustrating the schematic structure of a hard endoscope
for realizing stereoscopic observation according to a modification of the
thirteenth embodiment;
FIG. 25 is a view illustrating an essential portion according to a
fourteenth embodiment of the present invention;
FIG. 26 is a view illustrating the structure of a light source unit
according to a fifteenth embodiment of the present invention; and
FIG. 27 is a view illustrating the structure of an essential portion
according to a sixteenth embodiment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
As shown in FIG. 1, a stereo endoscope apparatus 1 according to a first
embodiment comprises: an endoscope 2 having an elongated insertion
portion; a control unit 7 to which the endoscope 2 is able to be fitted,
and which includes a light source portion, signal processing means, and
control means; and a monitor 8 comprising a color CRT for displaying image
signals output from the control unit 7.
At the front end of the elongated and flexible insertion portion 3 of the
endoscope 2, objective lens systems 4a and 4b are disposed which are
constituted by a pair of objective cover glasses confronting a position to
be observed and an objective lens. This pair of objective lens systems 4a
and 4b are positioned away from each other at a certain distance in order
to obtain the parallax which realizes a stereoscopic view. Optical guides
5a and 5b projecting from the positions behind the objective lens systems
4a and 4b are inserted into an insertion portion 3, and designed to be
able to be connected to the control unit 7 via an operation portion 6 of a
large diameter connected to the rear end of the insertion portion 3.
An image displayed by the color CRT monitor 8 can be imaged on the right
eye 12a or left eye 12b through, for example, shield glasses 11 having
shield filters 10a and 10b, the shield glasses 11 being provided outside
the control unit 7 with connecting cables 9a and 9b.
The shield filters 10a and 10b provided for the shield glasses 11 used by
an operator comprises, for example, liquid crystal shutter which utilizes
twistnematic liquid crystal. The twistnematic liquid crystal is
constituted in such a manner that the liquid crystal is sandwiched by two
deflector plates which are rotated by 90.degree. to each other wherein
when the electrode in the liquid crystal element is subjected to a
voltage, any light is prevented from transmission, while when it is
subjected to no voltage, light can transmit.
The structure of the control unit 7 will be described in detail.
The light source portion is constituted by: a strobe light 13 for emitting
a illuminating light; a strobe lamp electricity supplying circuit 14 the
output electricity of which is controlled by a control circuit 25
comprising a microprocessor or the like as the control portion thereof,
and which supplies electricity to the strobe lamp 13; and a convergence
lens 15 for converging the illuminating light emitting from the strobe
lamp 13.
The illuminating light emitting from the strobe lamp 13 and transmitted
through the convergence lens 15 is polarized by a prism 18 secured to a
rotational shaft 17 of a prism driving motor 16 the rotation of which is
controlled by the control circuit 25. The thus-polarized light is arranged
to be made incident upon either end surface of a pair of the optical
guides 5a or 5b made of fiber bundles.
An optical axis 19a extending perpendicular to the end surface of the
optical guide 5a to the inside portion of the control unit 7 is provided
with a solid state imaging element 21a with a light receiving lens 20a. On
the other hand, an optical axis 19b extending perpendicular to the end
surface of the optical guide 5b is provided with a solid state imaging
element 21b with a light receipt lens 20b. A pair of color mosaic type of
optical filters 49a and 49b are secured to the front surface of the solid
state imaging elements 21a and 21b.
The solid state imaging element 21a is arranged to be connected to and
thereby driven by a CCD driving circuit 22a which is controlled by the
control circuit 25. Similarly, the solid state imaging element 21b is
arranged to and driven by a CCD driving circuit 22b which is controlled by
the control circuit 25.
The solid state imaging element 21a is connected to an amplifier 26a which
amplifies the output signals from the solid state imaging element 21a, and
is connected to an A/D converter 27a via this amplifier 26a, the A/D
converter 27a conducting A/D conversion. This A/D converter 27a is
arranged to be connected to an image memory 28a which is controlled by the
control circuit 25.
Similarly, the solid state imaging element 21b is connected to an amplifier
26b, and is connected to an A/D converter 27b via this amplifier 26b. This
A/D converter 27b is arranged to be connected to an image memory 28b which
is controlled by the control circuit 25.
The image memories 28a and 28b are connected to a video switch 29 which is
controlled by the control circuit 25, and is connected to the color CRT
monitor 8 via the video switch 29 and a D/A converter 48.
The control circuit 25 controls the strobo lamp driving circuit 14 so as to
light the strobe lamp 13, for example, 60 times per second, and controls,
in synchronization with this lighting, the rotation of the prism driving
motor 16 so as to make the prism 18 interpose 30 times between the optical
axes 19a and 19b, respectively, and switches each image stored in the
image memories 28a and 28b in synchronization with the video switch 29 so
that the image is displayed by the color CRT monitor 8.
The control circuit 25 controls the shield filters 10a and 10b provided for
the shield glasses 11 in such a manner that the shield filters 10a and 10b
are made to be in the transmissible state or non-transmissible state in
synchronization with the image displayed on the color CRT monitor 8.
The operation of the apparatus according to the first embodiment the
structure of which has been described above will now be described.
Assuming that, the prism 18 which can be rotated by the prism driving motor
16 disposed in the control unit 7 is interposed between the optical axis
19a as shown in FIG. 1, the illuminating light emitted from the strobo
lamp 13 due to the supply of the electricity from the strobo lamp driving
circuit 14 is converged by the convergence lens 15. The thus-converged
light is made incident upon the prism 18. This prism 18 polarizes the
illuminating light and introduces the same to the end surface of the
optical guide 5a formed by a fiber bundle. This optical guide 5a
introduces, serving as a light guide, the illuminating light to the
emerging end thereof at the front end of the insertion portion 3. The
illuminating light emitted from this emerging end of the optical guide 5a
illuminates the portion to be observed through the objective lens system
4a (the thus-illuminated portion to be observed is called a B-field). The
light reflected from the B-field to be observed is made incident upon the
end surface of the other optical guide 5b at the front end of the
insertion portion 3. The optical guide 5b, serving as an image guide,
introduces the light reflected from B-field to be observed into the rear
end surface of the optical guide 5b at the fitting portion of the
endoscope 2 fitted to the control unit 7. The light reflected from B-field
is received by an image area through the light receiving lens 20b and the
color mosaic type of optical filter 49b located at the front surface of
the solid state imaging element 21b. At this time, a driving signal is
supplied from the CCD driving circuit 22b to the solid state imaging
element 21b, and an image signal of B-field is output, in response to the
driving signal, by the solid state imaging element 21b. The image signal
from B-field is amplified by the amplifier 26b, converted by the A/D
converter 27b into a digital signal, and supplied to the image memory 28b
wherein the signal is stored in the form of an image signal of B-field.
The image signal of B-field stored in the image memory 28b is displayed in
the form of the image of B-field by the color CRT monitor 8 due to
switching conducted by the control circuit 25 so as to electrically
connect the image memory 28 b with the color CRT monitor 8. At this time,
a voltage is applied by the control circuit 25 to the shield filter 10a
provided for the shield glasses 11 through the connection cable 9a whereby
the shield filter 10a is brought to a state in which light transmission is
prevented. As a result of this, the image of B-field displayed by the
color CRT monitor 8 passes through the shield filter 10b disposed to the
shield glasses 11, and imaged on the left eye 12b.
In a state where the prism 18 has been rotated by the prism driving motor
16 and interposed between the optical axis 19b, the optical guide 5b
introduces, serving as a light guide, the illuminating light, while the
other optical guide 5a introduces, serving as an image guide, the light
reflected from A-field. The light reflected from A-field is output in the
form of an image signal from the solid state imaging element 21a in
response to the driving signal from the CCD driving circuit 22a, and
supplied to the image memory 28a via the amplifier 26a and the A/D
converter 27a, wherein it is stored as an image signal of A-field. The
image signal of A-field stored in the image memory 28a is displayed in the
form of the image of A-field by the color CRT monitor 8 due to the
switching conducted by the control circuit 25 electrically connecting the
image memory 28a with the color CRT monitor 8. Furthermore, a voltage is
applied by the control circuit 25 to the shield filter 10b provided for
the shield glasses 11 through the connection cable 9b whereby the shield
filter 10b is brought to a state in which light transmission is prevented.
As a result of this, the image of A-field displayed by the color CRT
monitor 8 passes through the shield filter 10a disposed to the shield
glasses 11, and imaged on the right eye 12a.
As described above, the control circuit 25 performs such control that the
image of A-field is observed with the right eye 12a, while the image of
B-field is observed with the left eye 12b.
In FIG. 2, a state is shown in which the image of A-field and that of
B-field are successively output to the color CRT monitor 8.
As illustrated, the image of A-field which is the portion to be observed is
imaged on the right eye 12a since the shield filter 10b of the left eye
12b is brought to a light-stopped state, while the shield filter 10a of
the right eye 12a is brought to a light-tranmissible state. The image of
B-field is imaged on the left eye 12b since the shield filter 10a of the
right eye 12a is brought to a light-stopped state, while the shield filter
10b of the left eye 12b is brought to a light transmissible state. By
alternately switching, for example, 30 times per second, the shield
filters 10a and 10b between the state in which the light transmission is
prevented and the state in which light is allowed to pass through, the
portion to be observed can be observed as a stereo image having the
parallax between A-field and B-field due to the afterimage phenomenon.
As described above, according to the present invention, the stereo image
can be obtained in which slight unevenness of the surface of the portion
to be observed can be recognized. Furthermore, since a pair of optical
guides 5a and 5b are alternately used as the light guide and the image
guide, there is not any necessity for enlarging the outer diameter of the
insertion portion 3 of the endoscope 2.
Although in this embodiment, the color mosaic type of electronic endoscope
apparatus (it is also called a coincidence type) is used, a structure in
which ocular lenses are provided as an alternative to the solid state
imaging elements 21a and 21b may be employed, causing a macrographical
observation to be realized.
FIGS. 3 and 4 illustrate a second embodiment of the present invention,
wherein FIG. 3 is a view illustrating the structure of a stereo endoscope
apparatus and FIG. 4 illustrates means for switching optical guides.
The characteristic of this embodiment lies in that the present invention is
subjected to an endoscope (called a"fiber scope" hereinafter) in which
macrographical observation can be realized.
In FIG. 3, a stereo endoscope apparatus 1a comprises: the endoscope 2 the
structure of which is the same as that described in the first embodiment;
and a control unit 7a including the light source portion, observation
optical system, and the means for switching the optical guides 5a and 5b.
The light source portion of the control unit 7a comprises: a light source
lamp 30 for emitting illuminating light; a convergence lens 15a for
converging the illuminating light emitted from the light source lamp 30;
and a light guide 31 for introducing the illuminating light. The
observation optical system of the control unit 7a comprises: prisms 32a
and 33a for polarizing the light reflected from A-field which is the
portion to be observed, the light being emitted from the end surface of
the portion of the optical guide 5a at the portion for fitting with the
control unit 7a; and prisms 32b and 33b for polarizing the light reflected
from B-field which is the portion to be observed, the light being emitted
from the end surface of the portion of the optical guide 5b at the similar
portion. The system is constituted in such a manner that each light
reflected from the portions to be observed, namely, A-field and B-field,
is made incident upon the ocular systems 34a and 34b, respectively after
they have been polarized by the prisms 32a and 33a and prisms 32b and 33b.
As a result, the light is imaged on the right eye 12a or the left eye 12b.
Canging means 35 for switching the optical guides 5a and 5b of the control
unit 7a is constituted, for example, as shown in FIG. 4.
Referring to FIG. 4, a movable frame 36 is constituted in such a manner
that the distances between a frame 38a thereof and a frame 39 thereof and
between a frame 39 thereof and a frame 38b thereof are respectively the
same as the distance between the optical guides 5a and 5b. It is arranged
in such a manner that a relay lens 37a is arranged to be fitted within the
frame 38a, a light guide 31 is arranged to be fitted within the frame 39,
and a relay lens 37b is arranged to be fitted within the frame 38b. This
movable frame 36 can be moved perpendicular to an optical axis connecting
the end surfaces of the optical guides 5a and 5b with the prisms 32a and
32b. One end of the movable frame 36 is formed with an expanded portion 40
from which a driving rod 41 is projected. A piezoelectric element 42 such
as a bimorph is continued from the driving rod 41. The piezoelectric
element 42 is connected to a piezoelectric control circuit 43 where it is
controlled. As a result of the movement of the movable frame 36, the relay
lens 37a and the light guide 31 secured to the movable frame 36 are
selectively and respectively disposed on the optical axes of the light
guides 5a and 5b, and the light guide 31 and the relay lens 37ba are
selectively and respectively disposed on the optical axes of the optical
guides 5a and 5b.
The light guide 31 is arranged not to interfere with the movement of the
movable frame 36 due to its curved portion 31a which can contract or
expand at the time of this movement.
The operation of the thus-constituted apparatus according to the second
embodiment will now be described.
Assuming that the movable frame 36 which is moved by the switching means
disposed in the control unit 7a is in the state shown in FIG. 3, the
illuminating light emitted from the light source lamp 30 is converged by
the convergence lens 15a, made incident upon the end surface of the light
guide 31 which end surface confronts the light source lamp 30, introduced
by the light guide 31, and emerged from the opposite end surface. The
thus-emitted illuminating light is transmitted through the optical guide
5b in a manner similar to the first embodiment in which the optical guide
5b serves as a light guide. The thus-transmitted light is issued to
A-field which is the portion to be observed. The light reflected from
A-field which is the portion to be observed is transmitted through the
optical guide 5a which serves as an image guide through the objective lens
system 4a, and issued from the end surface of the optical guide 5a which
end surface confronts the relay lens 37a. The light reflected from A-field
which is the portion to be observed is made incident upon the prisms 32a
and 33a through the relay lens 37a, polarized by these prisms 32a and 33a,
made incident upon the ocular system 34a, and imaged on the right eye 12a.
When the movable frame 36 is moved by the switching means 35 causing the
light guide 31 and relay 37b to be disposed on the optical axes of the
optical guides 5a and 5b, the illuminating light is introduced through the
optical guide 5a which serves as a light guide, and the light reflected
from B-field which is the portion to be observed is introduced through the
optical guide 5b which serves as an image guide. As a result of this, the
light reflected from B-field which is the portion to be observed is imaged
on the left eye 12b.
That is, by alternately switching the light reflected from the portion to
be observed having the parallax between A-field and B-field by way of
switching the piezoelectric element 42 at 30 cycles, and imaging them to
the right eye 12a and the left eye 12b, respectively, a stereo image can
be observed due to an afterimage phenomenon.
As described above, the similar effect to the first embodiment can be
obtained in this embodiment.
Furthermore, the stereo image may be observed by a TV monitor similarly to
the first embodiment by connecting a TV camera to the ocular systems 34a
and 34b.
Furthermore, the switching means may be constituted in such a manner that
either of the relay lenses 37a or 37b and the light guide 31 are disposed
on a rotatable disc and the-thus constituted disc is disposed at the
central position between the optical guides 5a and 5b.
FIGS. 5 and 6 illustrate a third embodiment of the present invention
wherein FIG. 5 illustrates the structure of a stereo endoscope apparatus,
and FIG. 6 is a timing chart illustrating the operation of the stereo
endoscope apparatus.
The characteristic of this embodiment lies in that the present invention is
subjected to the electronic endoscope apparatus.
As shown in FIG. 5, the stereo endoscope apparatus 1b according to the
third embodiment comprises: an endoscope 2 which can be inserted into the
coelom and so forth; a control unit 7b connected to the endoscope 2 and
accommodates a signal processing system and so forth; and a color CRT
monitor 8 for displaying the image signal output from the control unit 7b.
The endoscope 2 and shield glasses 11 having the shield filters 10a and 10b
and connected to the control unit 7b with the connecting cables 9a and 9b
are constituted similarly to the first embodiment.
The structure of the control unit 7b will now be described.
Strobo lamps 13a and 13b are disposed, as light sources, on the optical
axes 19c and 19d connecting the strobe lamps 13a and 13b with the end
surfaces of the optical guides 5a and 5b. The outputs from the strobe
lamps 13a and 13b are controlled by a control circuit 25a, and strobo lamp
electricity supplying circuits 14a and 14b are connected to the strobe
lamps 13a and 13b. The illuminating light beams emitted from the strobe
lamps 13a and 13b are arranged to be converged by convergence lenses 15b
and 15c on the optical axes.
Either of the illuminating light beams is arranged to be made incident upon
the end surface of either of the optical guides 5a or 5b which is in the
form of a fiber bundle.
A prism 18a extending from the prism driving motor 16 the rotation of which
is controlled by the control circuit 25a polarizes the light reflected
from the portion to be observed which light is emitted from the end
surface of either of the optical guide 5a or 5b. The thus-polarized light
is arranged to be received by a solid state imaging element 21 secured to
the front surface of a color mosaic type of optical filter 49 through a
light receiving lens 20. This solid state imaging element 21 is driven by
a CCD driving circuit 22 which is controlled by the control circuit 25a,
and outputs an electric signal correspo | | |
