JP2002272674A - Optical scanning probe device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical scanning probe device suited for obtaining the image information of a desired part to be inspected, while reducing the influence of light reflected by a light transmitting member. SOLUTION: At the leading end of a probe, a condensing lens 26 held against the leading end of a retaining member 25 inside an optical frame 18 causes illuminating light emitted from the leading end of an optical fiber to be transmitted through a light-transmitting leading end cover 20 positioned in front of it, the light is focused in the form of a spot at the position of a focus 34 inside and near the surface of a living tissue 35, against which the front surface 20a of the leading end cover 20 is pressed. When the light reflected from the living tissue 35 near the focus 34 is received via a reverse optical path, the distance L37 between the front surface 20a and the focus 34 is held within a predetermined range whereby the amount of the reflected light received by the cover 20 is made greater than the amount of the light received from near the focus 34 on the living tissue 35 to provide image information with good S/N.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention transmits illuminating light from a light source device through an optical fiber provided in a probe, scans illuminating light emitted from a distal end face, and receives reflected light from a test portion side. And an optical scanning probe device for obtaining optical image information.

[0002]

2. Description of the Related Art In recent years, a technique for directly observing / diagnosing a living tissue without removing a living tissue by inserting a miniaturized probe-type confocal microscope into a body cavity has been established. The confocal microscope irradiates a subject with illumination light and images the reflected light as input information, and has an effect of removing the reflected light from the subject out of the focal position. this is,
This is called Z resolution (resolution in the depth direction). The amount of received light changes according to the depth position of the subject, and the full width at half maximum is defined as Z resolution (see FIG. 17). When the wavelength of the light source is λ, the refractive index of the object is n, and the numerical aperture of the optical system is NA, the Z resolution is 1.28λn / (NA · NA).

On the other hand, biological tissue has a reflectance of 1/1000 to 1000
It is extremely small, ie, 1/10000, and the amount of reflected light incident on the microscope from the subject decreases as the observation portion becomes deeper from the surface. Usually, in a probe-type confocal microscope,
Observation is performed at a depth of several tens of μm from the surface of the living tissue in a field of view of several hundreds of μm. It is important to remove an optical signal from a cover glass serving as a light-transmitting member provided in the vicinity for the purpose of protecting the optical system, and to position the focal point in the depth direction.

In a probe-type confocal microscope that is inserted into a body cavity and observes a living tissue at a cell level, the distance between the focal point of the illumination light and the cover glass (working distance: hereinafter referred to as WD and The prior art relating to (noted) is not found at present.

The prior art relating to the positioning in the depth direction according to claims 2 and 3 is disclosed in Japanese Patent Laid-Open No. 3-878.
As disclosed in U.S. Pat. No. 04, there is a method of sucking and fixing an observation tissue in a cup provided near a focusing lens system, and a method of pressing an observation site with a transparent tip cover as disclosed in Japanese Patent Application Laid-Open No. 2000-126114. Can be

[0006]

Since there is no prior art relating to claims 1 and 3, the signal from the cover glass becomes larger than the reflected light (signal) from the test object, and the desired test In some cases, images of objects were not obtained.

The problems of the prior arts according to claims 2 and 3 are as follows. JP-A-3-87804
With this configuration, since the observation site is sucked and fixed in the cup by suction, the operation is troublesome, and a suction port is required, which hinders miniaturization.

Further, according to the configuration of Japanese Patent Application Laid-Open No. 2000-126114, although it is firmly fixed in the pushing direction,
Since the fixing force is weak in the plane direction, the visual field range is several hundred μm
When the probe is relatively narrow, the observation site is out of the visual field range even if the probe is moved only a few mm, so that appropriate observation cannot be performed.

(Object of the Invention) The present invention has been made in view of the above points, and obtains desired image information of a portion to be inspected by reducing the influence of light reflected by a light transmitting member (cover glass). It is an object of the present invention to provide an optical scanning probe device suitable for the above.

It is another object of the present invention to provide an optical scanning probe device which can easily set the focal point of illumination light near the surface of a test portion and obtain optical image information on the test portion.

[0011]

The focal point of the illumination light emitted from the light source device is scanned on a portion to be inspected, and the reflected light of the illumination light from the portion to be inspected obtained by the scanning is transmitted to an observation device. In the optical scanning probe device, the distance between the light-transmitting member closest to the test portion and the focal point of the illumination light among the plurality of light-transmitting members disposed on the optical path of the illumination light, the light-transmitting member Is arranged such that the total amount N of the reflected light reflected by the end surface of the target and transmitted to the observation device and the amount of reflected light S reflected by the test portion and transmitted to the observation device satisfy S> N, so that the light transmittance is improved. The influence of the reflected light from the member is suppressed so that image information on the test object can be obtained.

An optical scanning probe device for scanning a focal point of illumination light emitted by a light source device with respect to a test portion and transmitting reflected light of the illumination light from the test portion obtained by the scanning to an observation device. Among the plurality of light-transmitting members arranged on the optical path of the illumination light, a member disposed around the light-transmitting member closest to the test section projects in the direction of the test section, and the focus Are set so as to be located on the same surface as the tip of the protruding portion or in the recess formed by the protruding portion, so that optical image information on the vicinity of the surface of the test portion can be easily obtained.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIGS. 1 to 19 show a first embodiment of the present invention.
FIG. 1 shows an overall configuration of an optical diagnostic apparatus provided with the first embodiment, FIG. 2 shows a configuration of an optical transmission / reception unit, FIG. 3 shows a configuration of a control unit, and FIG. 4 shows a configuration on the distal end side of the probe, FIG. 5 shows a configuration of the actuator, FIG. 6 shows a portion for fixing the actuator to the fixing member as viewed from an arrow A in FIG. 4 (B), and FIG. B) B)
8 shows a part for fixing the actuator to the intermediate member when viewed from the arrow, FIG. 8 shows a part for fixing the actuator to the holding member when viewed from the arrow C in FIG. 4A, and FIG. FIG. 10 shows the configuration of the distal end side of the probe of the modified example, and FIG.
Shows a portion on the rear surface side of the condenser lens where a light reflective vapor deposition film is provided, FIG. 12 shows a cross-sectional structure of a scanning mirror, and FIG. 13 shows a mirror portion before forming electrodes and the like.
FIG. 14 shows a mirror section on which electrodes and the like are formed, and FIGS. 15 and 16 show concrete examples of setting the wavelength of the light source and setting the working distance to 1.0.
FIGS. 17A and 17B show the optical path of light condensing at the focal point from the optical fiber tip when the distance is 0 mm and 2.0 mm, respectively. FIG. 17 shows the characteristics of the light receiving intensity with respect to the focal point and the distance before and after the focal point. FIG. 19 shows the manner in which the actuator is driven to scan the surface of the light, and FIG. 19 shows the manner in which the scanning mirror is driven to scan the surface of the light by the probe of FIG.

As shown in FIG. 1, an optical diagnostic apparatus 1 transmits an optical diagnostic light or receives an optical diagnostic light, and is connected to the optical transceiver 2. A control unit 3 that controls the operation of the optical transmission / reception unit 2 and performs image processing for optical diagnosis from received light and the like, and is connected to the control unit 3 and receives an image-processed video signal.
A monitor 4 for displaying a corresponding optical diagnostic image, a recording device 5 for recording a video signal, and
A direct-view optical scanning probe device (hereinafter simply abbreviated as a probe) 6 that transmits light for optical diagnosis and emits light for optical diagnosis from the distal end side to the test portion side.

The control unit 3 is connected to the probe 6 by a signal cable, and drives an actuator constituting a scanning unit 19 (see FIG. 4), which will be described later, incorporated in the probe tip 6a. Then, the focus position of the illumination light is scanned by the probe 6, and the reflected light reflected from the focus position in the portion to be inspected by the scanning is detected and imaged on the observation device side. Note that the observation device represents a portion excluding the probe 6 in FIG. 1 (specifically, the optical transmission / reception unit 2, the control unit 3, and the monitor 4. In this case, the recording device 5 may or may not be included in the observation device. Is also good).

As shown in FIG. 2, the light transmitting / receiving unit 2 includes a light source 7 for generating light for optical diagnosis, and a photodetector 8 for detecting reflected light of light illuminated on the object side by the probe 6.
And an optical transmission fiber 9. The two optical transmission fibers 9 are optically coupled by an optical coupling unit 10 near the center, and are bidirectionally branched into four terminals (couplers) 11 a and 11.
b, 11c, and 11d.

Normally, a laser oscillator for generating a laser beam is employed as the light source 7, and a terminal 1 of the optical transmission fiber 9 is used.
1a is connected to the light source 7, and the light generated by the light source 7 is
1a. This light is supplied to the terminal 1 by the optical coupling unit 10.
The light is branched into 1b and 11d, and the light transmitted to the terminal 11b travels to the probe 6 connected to the terminal 11b. The light supplied to the probe 6 side is guided to the tip 6a, and is emitted from the tip.

The reflected light from the part to be inspected is incident on the distal end surface of the probe 6, and the reflected light travels in the opposite direction and is branched by the optical coupling unit 10 into the terminals 11a and 11c. Terminal 1
The light guided to 1c is incident on the photodetector 8 disposed opposite to the terminal 11c, and is photoelectrically converted. This photoelectrically converted signal is input to an image processing circuit 15 constituting the control unit 3 shown in FIG.

The optical transmission fiber 9 generally has the following configuration:
In this embodiment, the end of the terminal 11d is closed, but the other three terminals 11a,
It can be used as a spare when one of 11b and 11c becomes unusable.

As shown in FIG. 3, the control unit 3 includes a light source driving circuit 12 for driving the light source 7, an X driving circuit 13 for scanning the light supplied from the light source 7 to the probe 6 in the X direction,
It comprises a Y drive circuit 14 for scanning in the Y direction and an image processing circuit 15 for performing image processing on a signal photoelectrically converted by the photodetector 8.

The light source driving circuit 12 is electrically connected to the light source 7, and the X driving circuit 13 and the Y driving circuit 14
Are electrically connected to (the actuators 28A and 28B of) the scanning unit 19 provided at the distal end portion 6a, and the input end of the image processing circuit 15 is electrically connected to the photodetector 8. The output terminal of the image processing circuit 15 is connected to the monitor 4 and the recording device 5.

As shown in FIG. 4, the probe 6 according to the first embodiment has a tubular hollow optical frame 18 attached to a distal end of a flexible hollow tube 16 via a fixing member 17. A scanning unit 19 for performing optical scanning is disposed inside the optical frame 18, and a front end cover (cover glass) as a light transmitting member is provided at an opening at the front end of the optical frame 18.
The front end portion 6a is formed by mounting the front end cover receiver 21 to which the front end 20 is mounted.

The rear end (base end) of the optical fiber 22 inserted into the tube 16 is connected to the terminal 11b of the optical transmission fiber 9, and the distal end side of the optical fiber 22 is a hollow portion of the fixing member 17. The ferrule 23 is fixed to a hole at the rear end of the substantially cylindrical holding member 25 constituting the optical unit 24 in a state where the ferrule 23 is integrally attached to the front end thereof.

At the distal end of the holding member 25, a condenser lens 26 for condensing the light emitted so as to expand from the distal end surface 22a of the optical fiber 22 is attached so that the illumination light can be transmitted to the test object (from the object). Specifically, an optical unit 24 that emits light toward the living tissue 35) shown in FIG. 9 and receives reflected light from the test object side is configured.

The distal end face 22a of the optical fiber 22 is 8
° is polished to an oblique plane. Further, as shown in FIG. 4, the distal end side of the optical fiber 22 is fixed to the holding member 25 so as to be slightly inclined vertically, for example, when the sectional view of FIG. 4B is viewed from the horizontal direction. ing. FIG.
FIG. 4A is a cross-sectional view from a direction perpendicular to the horizontal direction, and therefore, FIG. Then, the inclination of the distal end face 22a of the optical fiber 22 is corrected.

Accordingly, the illumination light emitted from the distal end face 22a of the optical fiber 22 travels along the optical axis 27 of the condenser lens 26, is condensed by the condenser lens 26, and forms a spot at the focal point 34. Further, the reflected light on the object side enters the distal end surface 22a of the optical fiber 22 via the condenser lens 26,
The incident light is detected, and optical information for the subject is imaged. In this case, the position of the focal point 34 and the distal end surface 22a having a small area of the optical fiber 22 have a focal relationship with each other with respect to the condenser lens 26 (and the distal end cover 20, and the refractive index in the optical path between them). A confocal optical system is formed so that light reflected by the optical fiber and incident on the distal end surface 22a of the optical fiber 22 is limited to light near the focal point.
The optical fiber 22 and the optical transmission fiber 9 may be either a single mode fiber or a multimode fiber.

The scanning unit 19 has a rear end fixed to the fixing member 17 and the front end of the holding member 25 is connected to the intermediate member 29.
(A low-speed drive side), an actuator 28B that drives the tip of the holding member 25 in a direction perpendicular to the drive direction of the actuator 28A (a high-speed drive side), and this actuator It comprises a substantially L-shaped intermediate member 29 which holds the rear end of 28B and has its rear end disposed between the holding member 25 and the fixing member 17. The distal end of the tube 16 is fixed to the outer peripheral surface of the fixing member 17 and the rear end 18 of the optical frame 18 is also fixed.

As shown in FIG. 5, the actuator 28A
(The same applies to 28B) includes a piezoelectric element plate 30 made of a PZT element plate or a quartz plate having piezoelectric characteristics, and a conductive member 31 longer than the piezoelectric element plate 30. FIG.
As shown in (2), the rear end of the actuator 28A extends to a horizontal plane 17a provided on a part of the outer periphery of the substantially tubular fixing member 17, and the front end thereof extends to the front end side of the substantially L-shaped intermediate member 29. The surface of the conductive member 31 is fixed to the front end side (top end side surface) 29a.

The side surface 29 of the intermediate member 29
a, and the rear end of the other actuator 28B is connected to the conductive member 31 on the rear end side surface 29b disposed at the rear end side of the position where the actuator 28A is fixed with respect to the condenser lens 26. The surface is fixed. The tip of the actuator 28B is
Is fixed to the front end side surface 25a of the base member by the surface of the conductive member 31.

The horizontal surface 17a of the fixing member 17
Side surface 29a, side surface 29b of intermediate member 29, holding member 25
A guide 32 is provided on the side surface 25a of the actuator, and the actuators 28A and 28B are guided and fixed by the guide 32. These guides 32 are shown in FIGS. 6 is a view of the fixing member 17 in FIG. 4 (A) as viewed in the direction of arrow A, FIG. 7 is a view of the intermediate member 29 in FIG. 4 (B) as viewed in the direction of arrow B, and FIG. FIG.

As shown in FIG. 4, the actuators 28A and 28B of the scanning unit 19 disposed in the optical frame 18 are provided.
Is connected to the distal end of the twisted pair signal cable 33, and the rear end of the signal cable 33 inserted into the tube 16 is connected to the X drive circuit 13 and the Y drive circuit 14.

As shown in FIG. 9, a cover receiver 21 for fixing the opening of the optical frame 18 in a watertight manner to protect the opening in a watertight manner is fixed. Hole 21a provided at opposing position
Is fixed to the front end cover (cover glass) 20 that transmits light. Therefore, the light emitted from the distal end face 22a of the optical fiber 22 by the light source 7 and collected by the condenser lens 26 passes through the distal end cover 20 and passes through the front focal point 3a.
At 4, the light is focused in a spot shape. Further, by driving the actuators 28A and 28B, the focus 3
4 scans the scanning plane 36 including the focal point 34 two-dimensionally.

In the present embodiment, the distance L37 (working distance: hereinafter referred to as WD) between the focal point 34 and the front surface (surface) 20a of the distal end cover 20 facing the living tissue 35 as the test object is 10 μm ≦ L. It is arranged so as to satisfy ≦ 2.0 mm so that the influence of the reflected light from the front end cover 20 is reduced, and the reflected light from near the focal point 34 can be detected.

The optical unit 19 includes a tube 16,
Watertightness is maintained by the optical frame 18, the front cover 20 and the cover receiver 21. Further, the condenser lens 26, the hole 21a of the tip cover 20 and the cover receiver 21, have an area that does not block the light emitted from the optical fiber 22. The scanning unit 19 and the optical unit 24 are the same as those shown in FIG.
Etc. may be used.

As shown in FIG. 10A, the scanning unit 19 is formed integrally with an optical unit, and this scanning unit 19 is composed of a condenser lens 26, a lens frame 40, and a spacing tube 4.
1, scanning mirror 42, mirror base 43, optical fiber fixing base 44, optical fiber 22, flexible substrate 4
5 and a substrate 46. As in the case of FIG. 4, the optical frame 1 is attached to the distal end of the tube 16 via a fixing member 17.
The rear end of the optical frame 18 is fixed, and the rear end of the cover receiver 21 to which the front end cover 20 is attached is fixed to the front end of the optical frame 18.

In the case of FIG. 10 (A), the tip of the fiber 22 is fixed to the optical fiber fixing table 4 inside the optical frame 18 with the ferrule 23 fixed integrally.
4 and the optical axis 27 of the condenser lens 26 and the inclined surface 4 inclined
4a and is fixed. In this case, the portion of the ferrule 23 on the outer peripheral side of the distal end of the optical fiber 22 is cut out in a tapered shape (conical shape), and the ferrule 23 is thinly covered on the fiber distal end surface 22b.

The rear end of the scanning mirror 42 is fixed to the front end of the optical fiber fixing base 44 so as to approach and face the fiber front end face 22b via the mirror base 43. In addition, a spacing tube 41 having a substantially U-shape is disposed at the front of the scanning mirror 42, and the focusing lens 2 is held by the lens frame 40 while maintaining a predetermined distance.
6 is fixed. FIG. 10 (B) is a diagram corresponding to D in FIG.
3D shows a cross section.

The lens frame 40 has a concave portion whose front side has a step-like enlarged diameter. The condensing lens 26 is accommodated in this concave portion from the front side, and an auxiliary ring 47 is inserted into the front end side to cover the lens. The rear end of the lens frame 40 is positioned and fixed by abutting the spacing tube 41 by fitting the cover receiver 21 into the optical frame 18 and pressing the cover receiver 21 toward the rear end side.

A light-reflective vapor-deposited film 48 is provided on a portion near the optical axis 27 on the rear surface side of the condenser lens 26 except for a hole 49 at the center thereof. That is, as shown in FIG. 11, near the center of the rear surface of the condenser lens 26 facing the optical fiber 22, the illumination light directly emitted from the optical fiber 22 corresponds to the light beam diameter of the condenser lens 26. A light-reflective vapor-deposited film 48 having a size
It is applied except for.

A mirror base 43 to which a scanning mirror 42 is fixed is fixed to the spacing tube 41. An optical fiber fixed to an optical fiber fixing base 44 via a ferrule 23 is fixed in a hollow portion of the mirror base 43. The distal end side of the fiber 22 is inserted.

The substrate 4 extends over the scanning mirror 42, the mirror base 43, and the optical fiber fixing base 44.
6 and the flexible board 45 are arranged inside the optical frame 18, and the rear end of the flexible board 45 is connected to an electric cable 50.
And are connected by soldering.

The tip of the tapered ferrule 23 polished integrally with the optical fiber 22 is connected to the scanning mirror 4.
The optical fiber 22 is opposed to the optical fiber 22 at a small interval without contact with the optical fiber 2, and the optical axis of the light emitted directly from the optical fiber 22 coincides with the central axis of the condenser lens 26. It is arranged to be inclined with respect to.

The hole 49 of the condenser lens 26 where the light-reflective vapor deposition film 48 is not provided, the hole 51 provided in the scanning mirror 42 (see FIG. 12), and the tip of the optical fiber 22 It is arranged so that the optical axis 27 of the illumination light directly emitted from the surface 22a coincides.

As shown in FIG. 12, the scanning mirror 42 etches one surface (hereinafter referred to as a surface) of the silicon substrate 52 to form a depression 53. Etching is also performed from the back surface side of the silicon substrate 52 to form a recess 54 and a through hole 55.

Further, there is provided a plate 56 which is adhered to the front surface side of the silicon substrate 52 and is electrically insulated from the silicon substrate 52 by an oxide layer on the silicon substrate 52. Further, after appropriately masking, a nitride film 57 is provided on the upper surface of the plate 56, and the plate portion is etched except for a portion necessary for reflection (that is, the mirror portion 58) to form the mirror portion 58.

FIG. 13 is a diagram showing the mirror section 58 at this time as viewed from above. Shaded portions 59a and 59 in FIG.
b, 59c and 59d indicate portions where the nitride film 57 is not provided, and are removed by etching. Further, as shown in FIG. 14, a conductive layer is formed from above on FIG. 13, and electrodes 60a, 60b, 60c, 60d for electrically driving (the mirror portion 58 of) the scanning mirror 42, and wiring patterns 61a, 61b, 61c. , 61d.

The pair of electrodes 60a and 60b and the electrode 60
c and 60d also serve as mirrors. Here, a portion not covered with the nitride film is removed by performing appropriate etching.

In this manner, a pair of electrodes 60a, 60a formed in the vicinity of the hole 51 so as to face in the vertical direction.
Ob is held so as to be vertically tiltable (tiltable) by left and right hinge portions 62a and 62b provided at the ends of the hatched portions 59a and 59b, and is opposed to the outside in the left and right direction. A pair of electrodes 60c, 60d formed at the end portions of the hatched portions 59c, 59d are held by longitudinal hinge portions 62c, 62d provided at the ends thereof so as to be tiltable in the left-right direction, and are gimbal type mirrors. A part 58 is formed.

The electrodes 60a, 60b, 60c, 60
Are the wiring patterns 61a, 61b, 61c, 61, respectively.
d, and these wiring patterns 61a, 61b, 6
1c and 61d are connected to the front end of the electric cable 50 via the board 46 and the flexible board 45, and the rear end of the electric cable 50 is connected to the X drive circuit 13 and the Y drive circuit 14.

Then, the X drive circuit 13 and the Y drive circuit 1
By outputting drive signals from the electrodes 60a, 6a,
0b and the electrodes 60c and 60 are driven to be tilted, respectively, so that the focal point 34 can perform surface scanning. A hole 51 having a size that does not block illumination light emitted from the optical fiber 22 is provided at the center of the mirror portion 58.

Next, the working distance WD is set to 10 μm ≦ L ≦
The grounds for setting 2.0 mm will be described with reference to FIGS. 15, 16, 17, and Tables 1, 2, 3, and 4. FIG.
Is a wavelength of 680 nm, a numerical aperture NA of 0.5, and a WD of 1.0.
Table 1 shows the optical path of the optical system shown in FIG.
Table 2 shows the change in the optical performance when the refractive index from the optical system to the converging point is changed.
6 is data showing the shape of FIG.

Table 1 (Change in optical performance due to change in refractive index of subject when WD is 1.0 mm) ―――――――――――――――――――――――― -Refractive index of subject | 1.33 | 1.4 | 1.5 Wavefront aberration RMS | 0.033 | 0.001 | 0.036 ----------------------------------------------------------------------------------------------------------- Table 2 (Table 1) (The wavelength for nd is 587.56 nm.) ―――――――――――――――――――――――――――――――――― RDY (radius of curvature) THI (between surfaces) nd (refractive index) Vd (Abbe number) ―――――――――――――――――――――――――――――― ―――――― Surface 1 INFINITY 11.20000 Surface 2 2.36494 1.405319 1.81474 37.03 Surface 3 -3.91541 1.013891 Surface 4 INFINITY 0.300000 1.51630 64.10 Surface 5 INFINITY 1.005000 1.41000 37.03 Surface 6 INFINITY 0.000000 ―― ―――――――――――――――――――――――――――――――――― ―――――――――――――――― ―――――――――――― Second page K: 0.000000 A:-. 977942E-02 B: 0.128213E-02 ――――――――――――――――――― ――――――――― ―――――――――――――――――――――――――――― Page 3 K: 0.000000 A: 0.272728E-01 B :-. 45647E-03 ―――――――――――――――――――――――――― FIG. 16 shows a wavelength of 680 nm, a numerical aperture of 0.5,
Table 3 shows an optical path in an optical system having a WD of 2.0 mm.
In the optical system No. 6, the change in the optical performance when the refractive index of the object is changed is shown. Table 4 shows the data of the shape of the condenser lens 26 in the optical system. FIG. 17 shows the distance from the focal point 34 and the light receiving intensity of the light from that position as a ratio.

Table 3 (Change in optical performance due to change in refractive index of subject when WD is 2.0 mm) ―――――――――――――――――――――――― -Refractive index of the object | 1.33 | 1.4 | 1.5 Wavefront aberration RMS | 0.071 | 0.001 | 0.077 Table 4 (Table 3) (The wavelength for nd is 587.56 nm.) ―――――――――――――――――――――――――――――――――― RDY (radius of curvature) THI (between surfaces) nd (refractive index) Vd (Abbe number) ―――――――――――――――――――――――――――――― ―――――― First surface INFINITY 11.20000 Second surface 2.41353 1.377416 1.81474 37.03 Third surface -3.80224 0.324356 Fourth surface INFINITY 0.300000 1.51630 64.10 Fifth surface INFINITY 2.005000 1.41000 37.03 Sixth surface INFINITY 0.000000 ―― ―――――――――――――――――――――――――――――――――― ―――――――――――――――― ―――――――――――― Second page K: 0.000000 A:-. 864143E-02 B: 0.990599E-03 ――――――――――――――――――― ――――――――― ―――――――――――――――――――――――――――― Page 3 K: 0.000000 A: 0.258114E-01 B :-. 701481E-03 ―――――――――――――――――――――――――――― K, A, B in Tables 2 and 4 are: This is an aspheric coefficient when the lens surface shape is set to a rotationally symmetric even-order aspheric surface. Here, assuming that the optical axis direction is the Z direction, the surface shape (each point (Z component in X and Y)) is expressed as follows.

Z = 1 / RDY × (S ^ 2) (1 + SQRT (1- (K + 1) × 1 / RDY ^
(-2) × S ^ 2)) + A × (S ^ 4 + B × S ^ 6 where S ^ 2 = X ^ 2 + Y ^ 2, and S ^ N indicates S to the Nth power. (Where
N represents 2, 4, 6, or -2, etc.). Also, SQRT
(C) represents the square root of C.

Further, the first surface is the tip end surface of the optical fiber 22 (confocal pinhole). The second and third surfaces are the condenser lens 26 (the effective lens diameter is Φ2.
4 mm) The fourth and fifth surfaces are cover glass (tip cover 20). The fifth and sixth surfaces are subjects (refractive index 1.4 with respect to a wavelength of 680 nm). Note that the refractive index of the object in FIGS.
The optical design is made on the premise that the number becomes 4.

The confocal optical system has an effect of removing the reflected light from the object out of the focus position. This is called Z resolution (resolution in the depth direction). The amount of received light changes according to the depth position of the subject, and the full width at half maximum is Z
Resolution (see FIG. 17).

The Z resolution is such that the wavelength of light from the light source 7 is λ,
When the object refractive index is n and the numerical aperture of the optical system is NA,
It is expressed as 1.28λn / (NA · NA). Since the size of the cell nucleus is about several μm to several tens of μm, a Z resolution of 5 μm or more is desirable for observing the cell nucleus.
For example, in an optical system having a Z resolution of 5 μm, when the change in the received light intensity follows a normal distribution as shown in FIG. 17, if the position of the subject is 10 μm from the focal position, the amount of received light decreases to about 1/1000 or less. I do.

Generally, glass coated with an anti-reflection film is used as the material of the tip cover 20, and its reflectivity is about 1/100, whereas the reflectance inside the living cell (cell membrane, nucleus) is high. Reflectance is 1/1000 to 1/1
Since it is about 00000, by setting WD to 10 μm or more, compared with the amount of light reflected from the front end cover 20,
A sufficient amount of reflected light from living cells can be obtained for observation.

That is, the amount of light received by the reflection from the living cell at the focal point 34 (referred to as S) is 1/1000 to 1/100.
000, and by setting the position of the front surface of the front end cover 20 to 10 μm or more from the focal point 34,
The amount of received light (assumed to be N) is (1/100) ×
(1/1000) or less, in other words, S
> N.

When observing various living cells, living tissues, and the like, the refractive index differs depending on the type. When observation is performed by inserting the distal end cover 20 into the body cavity,
Fluid enters between the body tissue 35 and the body fluid.

The body fluid has a refractive index that is significantly different from that of the living tissue 35. Since the refractive index of water is 1.33 and the refractive index of the living tissue 35 is around 1.4, the living tissue 35 in the body cavity is
When observing, it is necessary to realize good optical system resolution with a subject having a refractive index of about 1.33 to 1.5.

As an index indicating the optical performance, the wavefront aberration RM
Although there is S, if the value is larger than 0.07, the degradation of the resolution of the optical system starts. From Tables 1 and 3, as the change in the refractive index and the WD of the test object increase, the wavefront aberration RMS increases.
Is large and the optical performance is degraded. However, when the refractive index of the object is 1.33 to 1.5 and the WD is 2.0 mm or less, the wavefront aberration RMS can be suppressed, and the optical system It can be seen that the resolution can be maintained.

In this embodiment, the wavelength of the light source is 680
Although the nm is taken up, even if the light source has a wavelength other than 680 nm, if the WD is 2.0 mm or less, the wavefront aberration RMS can be suppressed, and the optical system resolution can be maintained. The wavelength other than 680 nm may be, for example, visible light, infrared light, ultraviolet light, near infrared light, or the like.

As in the present embodiment, the wavelength 68 of the illumination light
At 0 nm and NA of 0.5, the Z resolution is 4.9 μm. This has sufficient resolution for observation of living tissue (cell membrane, nucleus).

Next, the operation of the present embodiment will be described. In the above configuration, the probe 6 is inserted into a body cavity through a treatment tool insertion channel of an endoscope (not shown) and pressed against an observation site. In this state, the light source 7 is driven by the light source driving circuit 12, and the light source 7 generates light. This light is incident on a terminal 11a formed by the optical transmission fiber 9, and the light is branched by the optical coupling unit 10 into a terminal 11b and a terminal 11d. The light branched to the terminal 11d is guided to the closed end, but the light branched to the terminal 11b enters the optical fiber 22 built in the probe 6, and the tip 6a of the probe 6
It is led to.

The light guided to the tip 6a of the probe 6 is
The optical unit 24 allows the distal end surface 22 of the optical fiber 22 to be
After exiting from a, the light is condensed by the condenser lens 26, passes through the distal end cover 20, and forms a focal point 34 near the surface of the living tissue 35 as shown in FIG. At this time, the actuators 28A and 28B of the scanning unit 19 are driven by drive signals from the X drive circuit 13 and the Y drive circuit 14 of the control unit 3, and the focal point 34 is scanned in a scan plane 36 orthogonal to the optical axis 27. You.

The reflected light from the focal point 34 of the living tissue 35 and the reflected light from the front surface 20a of the tip cover 20 are:
Optical fiber 22, terminal 11b of optical transmission fiber 9, 1
The light passes through 1c and is incident on the fat detector 8.

The incident reflected light is converted into an electric signal by the photo detector 8 and transmitted to the image processing circuit 15.
At this time, the value of the electric signal corresponds to the amount of reflected light from the scanning surface 36 of the focal point 34 of the living tissue 35.

The image processing circuit 15 refers to the driving waveforms of the X driving circuit 13 and the Y driving circuit 14 to image the electric signal transmitted from the photodetector 8 as luminance information at the corresponding focal position, and display the image on the monitor 4. I do. Further, if necessary, the data is transmitted to the recording device 5 and recorded as electronic data.

At this time, the tip 6a of the probe 6 having the scanning unit 19 shown in FIG. 4 is scanned in the following manner. The X drive circuit 13 applies a sine wave positive voltage to the actuator 28B. The frequency of the sine wave is set to the resonance frequency of the system including the optical unit 24 and the scanning unit 19.

The piezoelectric element plate 30 of the actuator 28B repeatedly expands and contracts according to the voltage value that changes in a sinusoidal manner. On the other hand, since the conductive member 31 of the actuator 28B does not expand and contract, the actuator 28B moves in the direction 6 in FIG.
4 (vertical direction in FIG. 18). With this movement, the holding member 25 to which the actuator 28B is fixed is
By vibrating (the front end side with respect to the fixed rear end), the condenser lens 26 is also driven so as to vibrate, so that the focal direction is scanned in one direction (vertical direction).

The other actuator 28A has the Y
The drive circuit 14 applies a positive voltage as a sawtooth wave. By applying the voltage value of the sawtooth wave, the actuator 28A moves in a direction different from that of the actuator 28B, more specifically, in a direction 6 orthogonal to the direction.
5 (in the horizontal direction in FIG. 18). With this movement, via the intermediate member 29 and the actuator 28B,
As the holding member 25 connected to the actuator 28A vibrates, the focal position is scanned in the direction 65 orthogonal to the direction 64 accompanying the movement of the actuator 28B.

At this time, the frequency of the sawtooth wave is a value obtained by dividing the frequency of the sine wave by the number of scanning lines, whereby the focal point 34 is scanned in a plane while synchronizing the scanning in the two directions.

The scanning of the focal point 34 at the probe tip 6a shown in FIG. 10A will be described with reference to FIG. The illumination light emitted from the tip 22b of the optical fiber 22 passes through the through hole 55 of the silicon substrate 52 and the hole 51 at the center of the mirror portion 58, and travels toward the condenser lens 26. This light is reflected by the light-reflective vapor-deposited film 48 of the condenser lens 26, spreads toward the mirror 58 of the scanning mirror 42, and is reflected by the mirror 58.

Subsequently, the light travels from the portion of the condenser lens 26 where the light-reflective vapor-deposited film 48 is not applied to the opposite surface (front surface) of the condenser lens 26, and is condensed during this time. Proceeds through the tip cover 20 and becomes a spot at the focal point.

In this case, the electrode 6 forming the mirror section 58
To 0c and 60d, a saw-tooth voltage having a phase inverted to each other and having the same amplitude is applied, and a capacitance is formed with a GND portion formed in the concave portion 54, thereby generating an electrostatic force, thereby generating a mirror. The part 58 is a hinge part 62c, 62
Vibrates around d.

Also, a sine wave voltage having the same amplitude and the opposite phase is applied to the other electrodes 60 a and 60 b, and a capacitance is formed with the GND portion formed in the concave portion 54. Then, an electrostatic force is generated, and the mirror portion 58 vibrates around the hinge portions 62a and 62b.

At this time, the frequency of the sine wave is
Wherein the frequency of the sawtooth wave is equal to the frequency of the sine wave divided by the scan line. The inclination of the mirror portion 58 changes every moment due to the two voltage values, and accordingly, the position of the focal point 34 of the illumination light is surface-scanned.

This embodiment has the following effects. By setting the working distance WD to be 10 μm <L <2.0 mm, while maintaining the optical performance necessary for observing the living tissue 35, light reflected from other than the living tissue 35 and incident on the photodetector 8 can be obtained. By making the light smaller than the light from the living tissue 35, the living tissue 35 can be observed.

When the focal point is scanned by the configuration shown in FIG. 4, the optical axis 27 is fixed to the condenser lens 26, so that the condenser lens 26 can be easily designed. On the other hand, FIG.
When scanning of the focal point is performed with the configuration shown in FIG. 7, since only the mirror member 58 operates, the mass is light and high-speed scanning can be realized.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. Except for the cover receiver 21, the configuration is the same as that of the first embodiment.
Only different points from the first embodiment will be described.

As shown in FIG. 20, the cover receiver 21 is formed of a substantially tubular shape having a hole, and protrudes in the direction of the living tissue 35 from the front surface 20a of the distal end cover 20 facing the living tissue 35. The edge of the front end surface 21a of the cover receiver 21 which comes into contact with the living tissue 35 is chamfered 21.
b, 21c are given.

It should be noted that, for example, instead of the chamfer 21c on the outer peripheral side in FIG.
May be made substantially hemispherical on the tip side. The length s71 of the hole 21d from the front end surface 21a of the cover receiver 21 to the front surface 20a of the front cover 20 is equal to the focal length 34.
Is the distal end surface 2 of the cover receiver 21 in contact with the living tissue 35
1a, or is located in the hole 21d, and at the time of observation, the tip 6a of the probe 6 is pressed against the living tissue 35, and when the tissue 35 enters the hole 21d, the front surface 20a of the tip cover 20 D72 between the object and the surface of the living tissue 35 is 10 μm corresponding to the working distance WD (L37).
It is set so that m ≦ d ≦ 2.0 mm.

The front end cover 20 is fitted in a hole 21e of which the rear end side of the hole 21d of the cover receiver 21 has an enlarged diameter.

The length s71 is not unique because the penetration amount of the tissue 35 varies depending on the cross-sectional area of the hole 21d and the like. However, for example, the WD is 40 μm, and the diameter D73 of the cross-section of the hole 21d is Φ1 to Φ1. When it is about 1.5mm, 0.1 ~
0.6 mm.

The shape of the cover receiver 21 is shown in FIG.
The configuration shown in FIG. 23 may be used. FIG. 22 is an external view of the distal end 6a of the probe 6, and FIG. 23 is a longitudinal sectional view of the distal end 6a of the probe 6.

The front end cover 20 is fixed to the cover receiver 21 so as to be the same as or slightly projecting from the front surface 20 a of the cover receiver 21 facing the living tissue 35.
In 1a, a plurality of protrusions 74 are provided so as to protrude in the direction of the living tissue 35. Tip 74 of the protrusion 74
a has a substantially hemispherical shape, for example, in which a ridge line is cut off.

Further, as shown in FIG.
Is a distance B75 protruding from the front surface 20a of the front end cover 20, and a length L37 of the working distance WD is
The relationship of B ≧ L is satisfied, and the distal end 6a of the probe 6 is pressed against the living tissue 35, and the tissue 35
4, the distance d72 between the front surface 20a of the distal end cover 20 and the surface of the living tissue 35 is 10 μm ≦ d ≦ 2.
It is set to be 0 mm.

Next, the operation of the present embodiment will be described. Length s71 or B75 of the protruding portion of the cover receiver 21
However, the length L37 of the working distance WD and the relationship of s ≧ L or B ≧ L are satisfied, and at the time of observation, the distal end portion 6a of the probe 6 is pressed against the living tissue 35, and the tissue 35 enters the hole 21d. At this time, the distance d72 between the front surface 20a of the distal end cover 20 and the surface of the living tissue 35 is 1 corresponding to L37.
By setting the length to be 0 μm ≦ d ≦ 2.0 mm,
The focal point 34 can be located near the surface of the living tissue 35.

This embodiment has the following effects. Since the focal point 34 can be easily fixed to the vicinity of the surface of the living tissue 35 with a simple structure, more reflected light can be obtained than the living tissue 35, and the living tissue 35 can be reliably observed.

In addition, as in the first embodiment, L
37 by setting 10 μm ≦ d ≦ 2.0 mm, S
The / N ratio is improved, and the living tissue 35 can be observed more reliably.

Further, the configuration shown in FIGS. 22 and 23 facilitates the cleaning of the front surface 20a of the distal end cover 20.
Incidentally, regarding this effect, instead of the projecting portion 74, FIG.
As shown in FIG.
The same effect can be obtained by providing 0.

[Supplementary Notes] The illumination light emitted by the light source device is emitted through a plurality of light transmitting members including a light collecting optical system that collects light from the front end of the light transmitting member, and the front end becomes confocal with the plurality of light transmitting members. An optical scanning probe device that scans a focal point formed on the test portion side and transmits reflected light of the illumination light from the test portion obtained by the scanning to an observation device; The distance between the light-transmitting member closest to the test portion and the focal point of the illumination light among the plurality of light-transmitting members arranged is reflected by an end face of the light-transmitting member and transmitted to an observation device. The total amount of light N and the amount of reflected light S reflected by the subject and transmitted to the observation device are S>
An optical scanning probe device, wherein the optical scanning probe device is arranged to be N.

1. 2. The optical scanning probe device according to claim 1, wherein a distance L between the focal point of the illumination light and a light-transmitting member provided on an optical path of the illumination light and closest to the focal point is one.
The focal point is arranged closer to the portion to be inspected than the light transmitting member so that 0 μm ≦ L. 2. 2. The optical scanning probe device according to claim 1, wherein a distance L between a focal point of the illumination light and a light-transmitting member provided on an optical path of the illumination light and closest to the focal point is L ≦ 2.0 mm.
The focal point is disposed closer to the test object than the light transmissive member.

3. 2. The optical scanning probe device according to claim 1, wherein a distance L between the focal point of the illumination light and a light-transmitting member provided on an optical path of the illumination light and closest to the focal point is one.
The focal point is arranged closer to the subject than the light transmitting member so that 0 μm ≦ L ≦ 2.0 mm. 4. 3. The optical scanning probe device according to claim 2, wherein the length of the protruding portion is set such that a distance d between a surface of the light transmitting member facing the test portion and the surface of the test object satisfies 10 μm ≦ d. It is characterized by.

5. 3. The optical scanning probe device according to claim 2, wherein a length of the protruding portion is set such that a distance d between a surface of the light transmitting member facing the test portion and the surface of the test object is d ≦ 2.0 mm. It is characterized by having done. 6. 3. The optical scanning probe device according to claim 2, wherein the length of the protruding portion is set such that a distance d between a surface of the light transmitting member facing the test portion and the surface of the test object is 10 μm ≦ d ≦ 2.0 mm. Is set.

7. 4. The illumination device according to claim 1, wherein the illumination light emitted from the light source device is transmitted to be emitted from the terminal surface to the test portion, and the reflected light of the illumination light from the test portion is incident from the terminal surface. Transmission means for transmitting the illumination light emitted from the end face of the transmission means to the observation device; and fixing the light collection optical system together with the end face of the transmission means. Fixing means, a first moving means for moving the fixing means in a direction substantially orthogonal to the optical axis of the illumination light, and a direction substantially orthogonal to the optical axis of the illumination light and different from the first moving means An optical scanning probe device, comprising:

8. 4. The illumination device according to claim 1, wherein the illumination light emitted from the light source device is transmitted to be emitted from the terminal surface to the test portion, and the reflected light of the illumination light from the test portion is incident from the terminal surface. A movable plate provided with an opening through which the illumination light passes and a first reflecting surface; a support for supporting the movable plate; and illumination passing through the opening. A second reflecting surface for reflecting light toward the first reflecting surface; and a condensing optical system for condensing observation illumination light reflected from the first reflecting surface. Optical scanning probe device.

9. 8. The optical scanning probe device according to claim 8, wherein the second reflection surface is formed integrally with the light collecting optical system. 10. The transmitting means described in Supplementary Notes 7 and 8 is characterized by being made of an optical fiber. 11. The optical fiber according to Supplementary Note 10 is characterized by being composed of a single mode fiber. 12. The optical fiber according to Supplementary Note 10 is characterized by being composed of a multimode fiber.

[0100]

According to the first aspect of the present invention, the incident light amount N which is reflected by the light transmitting member provided on the optical path and is incident on the observation device is reflected by the living tissue near the focal point of the illumination light. The amount of light incident on the observation device is large, and the living tissue can be observed.

According to the second aspect of the present invention, the focal point of the illumination light can be easily positioned near the surface of the subject, and the amount of incident light reflected from the living tissue near the focal point of the illumination light and incident on the observation device. Can be obtained in many cases, so that a biological tissue image can be stably obtained. In addition, an effect that stable fixation can be achieved with a simple structure is obtained. According to the configuration of the third aspect, the same portion can be stably observed at a high S / N ratio.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of an optical diagnostic apparatus having a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of an optical transmission / reception unit.

FIG. 3 is a block diagram showing a configuration of a control unit.

FIG. 4 is a vertical cross-sectional view of the configuration on the distal end side of the probe viewed from two orthogonal scanning directions.

FIG. 5 is a perspective view showing a configuration of an actuator.

FIG. 6 is a front view showing a portion for fixing the actuator to the fixing member as viewed in the direction of arrow A in FIG. 4 (B).

FIG. 7 is a front view showing a portion for fixing the actuator to the intermediate member as viewed from the arrow B in FIG. 4 (B).

FIG. 8 is a front view showing a portion for fixing the actuator to the holding member as viewed from arrow C in FIG.

FIG. 9 is a cross-sectional view showing a state in which a distal end surface of a probe is pressed against a living tissue to perform optical diagnosis.

FIG. 10 is a vertical cross-sectional view of a configuration of the distal end side of a probe according to a modification and a cross-sectional view taken along the line DD.

FIG. 11 is a diagram showing a portion on the rear surface side of the condenser lens where a light-reflective vapor deposition film is provided.

FIG. 12 is a view schematically showing a sectional structure of a scanning mirror.

FIG. 13 is a plan view schematically showing a mirror section before forming electrodes and the like.

FIG. 14 is a plan view schematically showing a mirror section on which electrodes and the like are formed.

FIG. 15 is a diagram showing an optical path for focusing light from the tip of the optical fiber when the working distance is set to 1.0 mm by setting the wavelength of the light source specifically.

FIG. 16 is a diagram showing an optical path for focusing light from the tip of an optical fiber when a working distance is set to 2.0 mm by specifically setting a wavelength of a light source.

FIG. 17 is a diagram illustrating characteristics of light receiving intensity with respect to a focal point and distances before and after the focal point.

FIG. 18 is a diagram showing a state in which two actuators are driven by the probe in FIG. 4 to perform surface scanning with light.

FIG. 19 is a diagram showing a state in which a scanning mirror is driven by the probe in FIG. 10 to perform surface scanning with light.

FIG. 20 is a longitudinal sectional view showing a configuration near a tip of a probe according to a second embodiment of the present invention.

FIG. 21 is a longitudinal sectional view showing the configuration near the tip of the probe when the tip shape of the cover receiver of FIG. 20 is changed.

FIG. 22 is a perspective view showing a probe tip side when a protrusion is provided on a cover receiver.

FIG. 23 is a longitudinal sectional view showing the internal structure near the tip end in the case of FIG. 22;

FIG. 24 is a perspective view showing a distal end side of a probe according to a modification of FIG. 22;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Optical diagnostic apparatus 2 ... Optical transmission / reception part 3 ... Control part 4 ... Monitor 5 ... Recording device 6 ... Optical scanning probe device (probe) 7 ... Light source 8 ... Photodetector 9 ... Optical transmission fiber 11a-11d ... 4 terminal coupler 12 ... light source drive circuit 13 ... X drive circuit 14 ... Y drive circuit 15 ... image processing circuit 16 ... tube 17 ... fixing member 18 ... optical frame 19 ... scanning unit 20 ... tip cover (cover glass) 21 ... cover receiver 22 ... optical fiber 23 Ferrule 24 Optical unit 25 Holding member 26 Condensing lens 27 Optical axis 28A, 28B Actuator 29 Intermediate member 30 Piezoelectric element plate 31 Conductive member 32 Guide 33 Signal cable 34 Focus 35 ... living tissue 36 ... scanning surface 37 ... working distance WD 40 ... lens frame 42 ... scanning mirror 43 ... Over base 48 ... deposited film 52 ... silicon substrate 56 ... plate 58 ... mirror section 60 a to 60 d ... electrodes 61a-61d ... wiring pattern

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] April 11, 2001 (2001.4.1
1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0100

[Correction method] Change

[Correction contents]

[0100]

According to the configuration of claim 1, wherein, according to the present invention, anti living tissue in the focal point near the illumination light from the incident light quantity N which is incident on the reflection of a light transmissive member disposed on the optical path observation device <br The amount of light incident and incident on the observation device is large, and it is possible to observe the living tissue.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G059 AA05 AA06 BB12 EE01 EE02 FF01 HH02 HH06 JJ11 JJ13 JJ15 JJ17 JJ30 KK01 LL01 LL04 MM09 NN01 2H040 CA10 CA12 4C061 FF40 LL10

Claims (3)

[Claims] 1. An optical scanning probe device for scanning a focal point of illumination light emitted from a light source device with respect to a test portion and transmitting reflected light of the illumination light from the test portion obtained by the scanning to an observation device. In the plurality of light transmitting members disposed on the optical path of the illumination light, the distance between the light transmitting member closest to the test portion and the focal point of the illumination light is reflected by an end surface of the light transmitting member. An optical scanning probe device, wherein the total amount N of reflected light transmitted to the observation device and the reflected light amount S reflected by the subject and transmitted to the observation device satisfy S> N. 2. An optical scanning probe device for scanning a focal point of illumination light emitted from a light source device with respect to a test portion and transmitting reflected light of the illumination light from the test portion obtained by the scanning to an observation device. In, among the plurality of light-transmitting members arranged on the optical path of the illumination light, a member disposed around the light-transmitting member closest to the test portion projects in the direction of the test portion, The optical scanning probe device, wherein the focal point is located on the same plane as the tip of the protruding portion or in a concave portion formed by the protruding portion. 3. The distance between the light transmitting member closest to the test object and the focal point among the plurality of light transmitting members arranged on the optical path is reflected by the end face of the light transmitting suitable member and transmitted to the observation device. 3. The optical scanning probe device according to claim 2, wherein the total amount N of the reflected light and the reflected light amount S reflected by the subject and transmitted to the observation device satisfy S> N.