Optical fiber scanning apparatus and optical scanning type endoscope

An optical fiber scanning apparatus is the optical fiber scanning apparatus for which an optical fiber to which a permanent magnet is disposed and which is configured to emit illumination light from a distal end portion is arranged in a hollow portion of a magnetic field generation unit, the magnetic field generation unit is provided with four coil units each including a flexible substrate where a planar coil, a lead-out wiring layer of the planar coil and an external connection electrode pad are disposed, and an inside of the four coil units arranged in a square prism shape configures the hollow portion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an optical fiber scanning apparatus including a frame body to which a magnetic field generation unit is disposed, and an optical fiber in which a permanent magnet is disposed and which emits light from a distal end portion, and an optical scanning type endoscope including the optical fiber scanning apparatus at a distal end portion of an insertion portion.

2. Description of the Related Art

An image pickup apparatus using an image pickup device such as a CCD or a CMOS image sensor simultaneously receives reflected light from a subject by many photodetectors arranged in a matrix shape, and acquires an object image. In the case of an endoscope which photographs a dark inside of a body, an image in a range illuminated by light from a light source is acquired.

In contrast, in an optical scanning type image pickup apparatus, while an object is scan-irradiated by a light spot, the reflected light is successively received, and an object image is prepared based on the light reception data.

For example, in the optical scanning type image pickup apparatus, by an optical fiber scanning apparatus two-dimensionally scanning a distal end portion of an optical fiber that guides light from a light source, scan irradiation of the light spot is performed.

Optical fiber scanning of the optical fiber scanning apparatus is performed by controlling magnetic application from a magnetic field generation unit to an optical fiber where a magnet is disposed, for example.

Further, in an endoscope, diameter reduction of a distal end portion is strongly demanded in order to reduce invasion. In order to reduce a diameter of an optical scanning type endoscope for which an optical fiber scanning apparatus is disposed at a distal end portion, the diameter reduction of the optical fiber scanning type image pickup apparatus is an important issue.

Japanese Patent Application Laid-Open Publication No. 2008-116922 discloses an optical fiber scanning apparatus using magnetic force. In the conventional optical fiber scanning apparatus, an optical fiber where a permanent magnet is disposed is arranged at a center of a magnetic field generation unit formed of four electromagnets (magnetic field generation portions) which are orthogonally arranged/oppositely arranged inside a cylinder.

In the optical fiber scanning apparatus, a coil of the electromagnet is a winding coil in which a copper wire is wound in an elliptic shape around an outer periphery of a magnetic core formed of a soft magnetic body.

SUMMARY OF THE INVENTION

An optical fiber scanning apparatus of an embodiment includes: a frame body with a hollow portion, a cross section in a long axis direction of which is square and a distal end of which is an opening; and a magnetic field generation unit, and an optical fiber to which a permanent magnet is disposed and which is configured to emit illumination light from a distal end portion, which are disposed in the hollow portion of the frame body, the magnetic field generation unit is provided with four coil units each including a flexible substrate where two planar coils lined in the long axis direction, a lead-out wiring layer of the two planar coils and an external connection electrode pad extended from a rear end of the lead-out wiring layer are disposed, the four coil units are disposed on inner surfaces of the hollow portion, and an incidence portion of a detection unit configured to detect reflected light of the illumination light emitted from the optical fiber is arranged at a distal end portion of the frame body.

In addition, an optical fiber scanning apparatus of another embodiment is the optical fiber scanning apparatus for which an optical fiber to which a permanent magnet is disposed and which is configured to emit illumination light from a distal end portion is arranged in a hollow portion of a magnetic field generation unit, the magnetic field generation unit is provided with four coil units each including a flexible substrate where a planar coil, a lead-out wiring layer of the planar coil and an external connection electrode pad extended from a rear end of the lead-out wiring layer are disposed, and an inside of the four coil units arranged in a square prism shape configures the hollow portion.

Further, an optical scanning type endoscope of another embodiment has, at a distal end portion of an insertion portion, the optical fiber scanning apparatus for which an optical fiber to which a permanent magnet is disposed and which is configured to emit illumination light from a distal end portion is arranged in a hollow portion of a magnetic field generation unit, wherein the magnetic field generation unit is provided with four coil units each including a flexible substrate where a planar coil, a lead-out wiring layer of the planar coil and an external connection electrode pad extended from a rear end of the lead-out wiring layer are disposed, and an inside of the four coil units arranged in a square prism shape configures the hollow portion.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

First Embodiment

UsingFIG. 1toFIG. 3, an optical fiber scanning apparatus10in the first embodiment will be described. Note that, in a following description, drawings based on respective embodiments are schematic, it is to be taken into consideration that relations between thicknesses and widths of respective portions and ratios of the thicknesses of the respective portions or the like are different from actual ones, and portions where mutual dimensional relations or ratios are different are sometimes included among the drawings.

The optical fiber scanning apparatus10has a frame body11, an optical fiber28arranged along a center line O in a long axis (Z axis) direction of a hollow portion11H of the frame body11, a magnetic field generation unit20U provided with four coil units20A to20D, and an illumination optical system32.

The optical fiber28guides light from a light source unit174(seeFIG. 21) and emits illumination light from a distal end portion. The illumination light spot-irradiates an object through the illumination optical system32formed of a plurality of lenses. Note that the illumination optical system32is not an essential component.

To a rear portion of the distal end portion of the optical fiber28, a permanent magnet29is bonded by an adhesive or the like. For example, the permanent magnet29formed of an SmCo alloy is a cylindrical type and is magnetized in a longitudinal direction. The optical fiber28is inserted through a through-hole33H of a holding member33, and is bonded to the holding member33. The distal end portion of the optical fiber28to which a bond portion (proximal end portion) of the holding member33is fixed is movable within an XY plane vertically and horizontally with the proximal end portion as a base point.

The frame body11has the hollow portion11H, a cross section of which orthogonal to the center line O is square. It is preferable that the frame body11is formed of a metal for accurate processing, and it is especially preferable that the frame body11is formed of stainless steel or an aluminum alloy which is excellent in machinability and weather resistance. In addition, from a viewpoint of magnetic flux leakage reduction or the like, it is also especially preferable that the frame body11is formed of a soft magnetic material of high magnetic permeability such as permalloy.

A coil unit20A is bonded by an adhesive or the like for example to a first surface11SA of the hollow portion11H of the frame body11, and a coil unit20B is bonded to a second surface11SB. Similarly, a coil unit20C is bonded to a third surface11SC, and a coil unit20D is bonded to a fourth surface11SD. The coil units20A to20D are in a same configuration. Note that, hereinafter, each of the coil units20A to20D is referred to as a coil unit20.

As illustrated inFIG. 3andFIG. 4or the like, the coil unit20is formed of a wiring board24on which a coil chip21including a planar coil21S is flip-chip-mounted.

For the coil chip21, to a base body22formed of silicon, the planar coil21S which is a drive coil in a spiral shape is disposed through an insulating layer of a silicon oxide or the like (not shown in the figure). The planar coil21S is covered with an insulating layer23formed of a resin such as polyimide or epoxy except for contact hole portions at an upper part of a bond pad21P at both ends. The illustrated planar coil21S includes a conductor layer (planar coil) formed of a patterned low resistance metal such as copper or gold and an insulating layer covering the conductor layer.

Note that, while a bond pad is arranged also at a coil center in the coil chip21, in order to provide the bond pad around the coil, one insulating layer/lead-out wiring layer may be provided further, or the coil chip21may be a multilayer coil in which a plurality of coils are laminated through the insulating layer.

The coil chip21can be manufactured by disposing many planar coils on a silicon wafer and then dividing the planar coils by a MEMS semiconductor process. By using a highly accurate resist mask manufactured by a photolithographic method using photoresist and a photomask and performing patterning by an additive method, a subtraction method or the like, the coil chip21including the planar coil21S with high accuracy can be easily manufactured in large quantities.

The wiring board24is a flexible wiring board in which a coil connection electrode pad24PA, an external connection electrode pad24PB, and a lead-out wiring layer24PL which connects the coil connection electrode pad24PA and the external connection electrode pad24PB are disposed to a flexible substrate24F.

In order to dispose the lead-out wiring layer24PL or the like to the flexible substrate24F formed of an insulating resin such as polyimide, a conventional printed wiring board manufacturing method is used. For example, the wiring board24is manufactured by forming an etching mask on a polyimide substrate to which copper foil is bonded and then etching the copper foil. That is, the coil connection electrode pad24PA, the external connection electrode pad24PB and the lead-out wiring layer24PL are formed of an integrated copper layer.

To the coil connection electrode pad24PA and the external connection electrode pad24PB, a connection pad formed of nickel/gold or the like may be disposed on the copper layer. In addition, an area excluding the coil connection electrode pad24PA and the external connection electrode pad24PB of the wiring board24may be covered with the insulating layer. In addition, in a case that the wiring board24is a multilayer wiring board, the coil connection electrode pad24PA and the external connection electrode pad24PB may be disposed on different main surfaces.

To the coil connection electrode pad24PA of the wiring board24, the bond pad21P of the coil chip21is bonded. To the external connection electrode pad24PB of the wiring board24, wiring75L connected with a drive control unit175(seeFIG. 21) which supplies a driving current is bonded. The planar coil21S generates a magnetic field in a direction orthogonal to the main surface of the coil chip21when the driving current is applied to the bond pad21P. Strength of the magnetic field is set by a current value of the driving current and a number of turns of a spiral coil or the like. When a direction of the driving current flowing through the coil is inverted, the direction of the generated magnetic field is inverted.

As already described, in the hollow portion11H of the frame body11, the magnetic field generation unit20U provided with the four coil units20each including the planar coil21S is disposed. That is, planar coils21S1and21S2are disposed respectively on the first surface11SA and the second surface11SB of the frame body11, and planar coils21S3and21S4are disposed respectively on the third surface11SC and the fourth surface11SD which are orthogonal to each other. That is, the planar coil21S1and the planar coil21S3are arranged at opposite positions, and the planar coil21S2and the planar coil21S4are arranged at opposite positions.

Therefore, the planar coils21S1and21S3generate the magnetic field in an X axis direction, and the planar coils21S2and21S4generate the magnetic field in a Y axis direction.

Note that, in the optical fiber scanning apparatus10, a surface where the coil chip21is disposed is bonded with the frame body11; however, an opposite surface may be bonded with the frame body11.

Next, a driving method of the optical fiber scanning apparatus10will be simply described.

As illustrated inFIG. 5A, when the driving current is supplied to the planar coil21S1, for example, the magnetic field in which an inner surface side is an N pole is generated. Simultaneously, when the driving current is supplied to the planar coil21S3, for example, the magnetic field in which the inner surface side is an S pole is generated. Then, a rear end side (N pole) of the permanent magnet29arranged within the magnetic field is pulled up in a Y axis upper direction. Therefore, a distal end of the optical fiber28is also moved in the Y axis upper direction.

On the other hand, as illustrated inFIG. 5B, when the driving current in the direction opposite to that in the case ofFIG. 5Ais supplied to the planar coil21S1, the magnetic field in which the inner surface side is the S pole is generated. Similarly, when the driving current in the direction opposite to that in the case ofFIG. 5Ais supplied to the planar coil21S3, the magnetic field in which the inner surface side is the N pole is generated. Then, the rear end side (N pole) of the permanent magnet29arranged within the magnetic field is pulled down in a Y axis lower direction. Therefore, the distal end portion of the optical fiber28is also moved in the Y axis lower direction.

Therefore, by controlling the direction of the driving current supplied to the planar coils21S1and21S3, the distal end portion of the optical fiber28is scanned in the Y axis direction. Similarly, by controlling the direction of the driving current supplied to the planar coils21S2and21S4, the distal end portion of the optical fiber28is scanned in the X axis direction.

Note that the permanent magnet29, the optical fiber or the magnetic field generation unit20U may be arranged such that the magnetic field is applied to a distal end side of the permanent magnet29. In addition, for example, scanning is possible even when only the planar coil21S1and the planar coil21S2are driven.

By controlling the direction of the driving current supplied to the four planar coils21S1to21S4, the distal end portion of the optical fiber28is two-dimensionally scanned within the XY plane. A scanning width is controlled by a driving current value. As a result, a light spot emitted from the distal end portion of the optical fiber28is two-dimensionally scanned.

As a two-dimensional scanning system, a spiral scanning system illustrated inFIG. 6Aor a raster scanning system illustrated inFIG. 6Bis preferable since image processing is easy, and the raster scanning system is especially preferable since illumination can be uniformly performed.

Then, the optical fiber scanning apparatus10has a small diameter since the magnetic field generation unit20U is formed of extremely thin coil chips21A to21D, a thickness of which is equal to or larger than 10 μm and is equal to or smaller than 200 μm for example, because the planar coil is provided. Further, since the coil units20A to20D are respectively disposed on inner surfaces of the hollow portion11H of the square cross section of the frame body11, the coil units20A to20D are accurately oppositely arranged/orthogonally arranged.

Therefore, the optical fiber scanning apparatus10has the small diameter and is capable of performing highly accurate scan irradiation. Further, since the planar coil21S (coil chip21) of each coil unit20is flip-chip-mounted on the wiring board24including the external connection electrode pad24PB, it is easy to connect wiring which transmits driving power.

Note that, without using the frame body11, after arranging the coil units20A to20D in a square prism shape, the coil units20A to20D may be fixed by molding an outer peripheral portion by a resin or the like. That is, the frame body11is not an essential component of the optical fiber scanning apparatus10.

Modifications of First Embodiment

Next, optical fiber scanning apparatuses10A and10B in modifications of the first embodiment will be described. Since the optical fiber scanning apparatuses10A and10B are similar to the optical fiber scanning apparatus10, descriptions of components of same functions are omitted. Note that, in the following diagrams, the optical fiber and the magnetic field generation unit or the like are sometimes not illustrated.

The optical fiber scanning apparatuses10A and10B have effects of the optical fiber scanning apparatus10and have further characteristic effects.

Modification 1 of First Embodiment

As illustrated inFIG. 7, in the optical fiber scanning apparatus10A, four coil units30(30A to30D) of a magnetic field generation unit20UA is a wiring board34in which a planar coil34S in the spiral shape, a lead-out wiring layer34PL and an electrode pad34PB are disposed to a flexible substrate34F by a copper layer which is an integrated same material. That is, the wiring board34includes the planar coil34S. The coil units30A to30D are in the same configuration.

The wiring board34where the planar coil34S is disposed can be manufactured by the almost same method as the wiring board24, that is, by a general purpose printed wiring board manufacturing method. Therefore, the planar coil34S with relatively high dimension accuracy can be manufactured simultaneously with the lead-out wiring layer34PL and the electrode pad34PB.

For the magnetic field generation unit20UA, the coil units30A to30D are arranged in the square prism shape. Note that, while a surface where the planar coil34S or the like is disposed is an inner surface of a square prism inFIG. 7, the surface where the planar coil34S or the like is disposed may be an outer surface of the square prism. In addition, in the case that the wiring board34is a double-sided wiring board, the surface where the planar coil34S is disposed and the surface where the electrode pad34PB is disposed may be different for example.

Note that, like the optical fiber scanning apparatus10, the coil units30A to30D may be bonded to the inner surfaces of the hollow portion of the square cross section of the frame body.

Since the wiring board34includes the planar coil34S, the optical fiber scanning apparatus10A is easier to manufacture and more inexpensive than the optical fiber scanning apparatus10.

Modification 2 of First Embodiment

As illustrated inFIG. 8, in the optical fiber scanning apparatus10B, four coil units40(40A to40D) of a magnetic field generation unit20UB includes a wiring board44in which a planar coil44S is disposed to a flexible substrate44F as a conductor layer integrated with a lead-out wiring layer44PL and an electrode pad44PB. That is, similarly to the optical fiber scanning apparatus10A, the wiring board44includes the planar coil44S.

Then, in the optical fiber scanning apparatus10B, further, a coil chip41provided with a second planar coil41S is flip-chip-mounted right above the planar coil44S of the wiring board44. That is, by disposing and connecting the second planar coil41S of the coil chip41, such that a center of the spiral coil coincides, on the planar coil44S of the wiring board44, the multilayer coil formed of the two planar coils is configured. The coil units40A to40D are in the same configuration.

The coil chip41is in the almost same configuration as the already-described coil chip21with the silicon as the base body.

As illustrated inFIG. 9, the planar coil44S of the wiring board44and the second planar coil41S of the coil chip41are wound in the same direction, and configure the multilayer coil which generates the magnetic fields in the same direction when a current is applied.

The strength of the magnetic field generated by the spiral coil increases proportionally to the number of turns of the coil. Therefore, in order to efficiently drive the planar coil arranged within a predetermined occupancy area with low power, the multilayer coil is preferable. However, multilayer coil manufacture needs not only disposition of an insulating layer between the coils but also complicated processes such as flattening of the insulating layer with recesses and projections by the coil of a lower layer in order to guarantee dimension accuracy of the coil of an upper layer.

In the optical fiber scanning apparatus10B, the multiplayer coil can be configured just by flip-chip-mounting the coil chip41to the wiring board44. The optical fiber scanning apparatus10B provided with the multilayer coil can be driven with lower power and with better efficiency than the optical fiber scanning apparatus10.

Second Embodiment

Next, an optical fiber scanning apparatus10C in a second embodiment will be described. Since the optical fiber scanning apparatus10C is similar to the optical fiber scanning apparatus10or the like, the descriptions of the components of the same functions are omitted.

In the optical fiber scanning apparatus10C, four coil units50(50A to50D) of a magnetic field generation unit20UC include two planar coils51S1and51S2lined in the long axis direction. The coil units50A to50D are in the same configuration.

That is, as illustrated inFIG. 10andFIG. 11, on a wiring board54of the coil unit50, a coil chip51A1provided with a planar coil51S1and a coil chip51A2provided with a planar coil51S2are flip-chip-mounted. The coil chips51A1and51A2are in the almost same configuration as the coil chip21.

A permanent magnet29C disposed to the optical fiber28has an almost same length as a distance between the centers of spirals of the two planar coils51S1and51S2. Note that, instead of the long permanent magnet29C, two permanent magnets may be disposed to the optical fiber28.

As illustrated inFIG. 12AandFIG. 12B, the two serially connected planar coils51S1and51S2generate the magnetic fields in the same direction (FIG. 12A) or generate the magnetic fields in the opposite directions (FIG. 12B) depending on a difference of a connection state.

Next, a driving method of the optical fiber scanning apparatus10C will be simply described. In the optical fiber scanning apparatus10C, a first driving method or a second driving method can be used.

As illustrated inFIG. 13A, in the first driving method, the two planar coils51S1and51S2of the coil unit50generate the magnetic fields in the same direction.

Planar coils51S1A and51S2A of the coil unit50A both generate the magnetic fields in which the inner surface side is the N pole for example, and planar coils51S1C and51S2C of the coil unit50C both generate the magnetic fields in which the inner surface side is the S pole for example.

The distal end side (N pole) of the permanent magnet29C is pulled up in an upper direction (+Y direction) by the planar coils51S1A and51S1C. On the other hand, the rear end side (S pole) of the permanent magnet29C receives force in a lower direction (−Y direction) by the planar coils51S2A and51S2C. By vibrations of the permanent magnet29C by magnetic force from the planar coils51S, the optical fiber28performs resonant vibrations of a higher mode with an antinode and a node in the longitudinal direction, a high resonance frequency is obtained by the resonant vibrations of the higher mode, and scanning at a high speed becomes possible.

On the other hand, as illustrated inFIG. 13B, in the second driving method, the two planar coils51S1A and51S2A of the coil unit50A generate the magnetic fields in the opposite directions. In addition, the two planar coils51S1C and51S2C of the coil unit50C also generate the magnetic fields in the opposite directions.

The distal end side (N pole) of the permanent magnet29C is pulled up in the upper direction (+Y direction) by the planar coils51S1A and51S1C. The rear end side (S pole) of the permanent magnet29C is also pulled up in the upper direction (+Y direction) by the planar coils51S2A and51S2C. Thus, the optical fiber28is capable of scanning of a predetermined amplitude even when the magnetic field generated by each coil is weak.

Note that, in the case that two short permanent magnets are disposed, the driving method different from the above is also possible.

Since the optical fiber scanning apparatus10C can scan the optical fiber28more efficiently than the optical fiber scanning apparatus10, power consumption is low.

Modifications of Second Embodiment

Next, optical fiber scanning apparatuses10D to10F in modifications of the second embodiment will be described. Since the optical fiber scanning apparatuses10D to10F are similar to the optical fiber scanning apparatus10C, the descriptions of the components of the same functions are omitted.

In the optical fiber scanning apparatuses10D to10F, similarly to the optical fiber scanning apparatus10C, each coil unit is provided with two planar coils lined in the long axis direction. Therefore, the optical fiber scanning apparatuses10D to10F have effects of the optical fiber scanning apparatus10C and have further characteristic effects.

Modification 1 of Second Embodiment

As illustrated inFIG. 14, in the optical fiber scanning apparatus10D, for coil units60(60A to60D) of a magnetic field generation unit20UD, a coil chip61provided with a base body62and two planar coils61S1and61S2lined in the long axis direction of the base body62respectively is flip-chip-mounted on a wiring board64. For the wiring board64, a coil connection electrode pad64PA, a lead-out wiring layer64PL and an external connection electrode pad64PB are disposed to a flexible substrate64F as an integrated conductor layer.

Since one coil chip61is flip-chip-mounted on the coil unit60, the optical fiber scanning apparatus10D is easy to manufacture.

Modification 2 of Second Embodiment

As illustrated inFIG. 15, in the optical fiber scanning apparatus10E in the modification 2 of the second embodiment, coil units70(70A to70D) of a magnetic field generation unit20UE are a wiring board74where two planar coils74S1and74S2are lined in the long axis direction.

That is, for the wiring board74, the two planar coils74S1and74S2, a lead-out wiring layer74PL and an external connection electrode pad74PB are disposed to a flexible substrate74F as an integrated conductor layer.

Since the wiring board74includes the two planar coils74S1and74S2, manufacture is easier and it is more inexpensive than the optical fiber scanning apparatuses10C and10D.

Modification 3 of Second Embodiment

As illustrated inFIG. 16, in the optical fiber scanning apparatus10F in the modification 3 of the second embodiment, for coil units80(80A to80D) of a magnetic field generation unit20UF, coil chips81A1and81A2are flip-chip-mounted further on a wiring board84including two planar coils81S1and81S2.

A second planar coil81S1is disposed to the coil chip81A1, and a second planar coil81S2is disposed to the coil chip81A2. The coil units70A to70D are in the same configuration.

In the optical fiber scanning apparatus10F, the coil chips81A1and81A2provided with a base body82and the second planar coils81S1and81S2disposed to the base body82are flip-chip-mounted right above each of two planar coils84S1and84S2of the wiring board84, and each of the planar coils84S1and84S2and each of the second planar coils81S1and81S2are connected and configure the multilayer coil.

FIG. 17illustrates a connection example of the four planar coils84S1,84S2,81S1and81S2configuring two multilayer coils of the coil unit80. In the example illustrated inFIG. 17, the two multilayer coils generate the magnetic fields in the same direction. However, the magnetic fields in the opposite directions are generated depending on a connection state as already described.

The optical fiber scanning apparatus10E can scan the optical fiber28with further lower power than the optical fiber scanning apparatus10C.

Note that, similarly to the optical fiber scanning apparatus10D, it is needless to say that the optical fiber scanning apparatus in which a coil chip with two planar coils disposed to one base body is flip-chip-mounted on the wiring board64has the same effects as the optical fiber scanning apparatuses10D and10F.

Third Embodiment

As illustrated inFIG. 18andFIG. 19, while an optical fiber scanning apparatus10X in the third embodiment is similar to the already described optical fiber scanning apparatuses10and10A to10F, two incidence portions16of a detection unit176(seeFIG. 21) which detects reflected light of light with which an object is irradiated from the optical fiber28are arranged in the frame body11.

Note thatFIG. 18is a sectional view in a long axis orthogonal direction of the optical fiber scanning apparatus10X, andFIG. 19is a sectional view along a XVIIII-XVIIII line inFIG. 18.

As illustrated inFIG. 18, the incidence portion16is a distal end portion of an optical fiber (also referred to as “detection fiber”, hereinafter)27which guides the reflected light. The reflected light made incident from the distal end portion of the optical fiber27through a detection optical system46formed of a plurality of lenses is guided to a main body device3(seeFIG. 20andFIG. 21). Note that it is preferable that the optical fiber27is a fiber bundle formed of a plurality of optical fibers. In addition, there may be one incidence portion16or three or more incidence portions16.

Here, the optical fiber27is considered as a part of the detection unit176. In addition, a photodiode (PD) element or the like which detects the reflected light may be directly arranged in the frame body11as the incidence portion16.

For the optical fiber scanning apparatus10X, since the incidence portions16of the detection unit176are arranged in the frame body11, a structure is simple as a whole and the diameter is small compared to the optical fiber scanning apparatus in which the incidence portion16is disposed to a different member.

Fourth Embodiment

An optical scanning type endoscope (referred to as “endoscope” hereinafter)2in the fourth embodiment illustrated inFIG. 20has one of the already-described optical fiber scanning apparatuses10and10A to10X at a distal end portion94of an insertion portion91. Hereinafter, the description will be given with the endoscope2including the optical fiber scanning apparatus10as an example.

An optical scanning type endoscope system (referred to as “endoscope system” hereinafter)1including the endoscope2is provided with the endoscope2, the main body device3having functions of a light source device and a video processor, and a monitor4. The endoscope2irradiates a subject with the illumination light while performing two-dimensional scanning by the optical fiber scanning apparatus10, detects the reflected light (return light) from the subject, performs data processing in the main body device3, and displays a generated subject image on the monitor4.

The endoscope2is provided with an elongated insertion portion91to be inserted into a living body, an operation portion92, and a universal cable93to which an electric cable or the like is inserted. The insertion portion91of the endoscope2includes the distal end portion94, a bending portion95, and a flexible tube portion96. Note that, while the endoscope2of the embodiment is a so-called flexible endoscope, even a so-called rigid endoscope in which the insertion portion91is rigid has the effects described later.

To the operation portion92, a bending operation knob97for performing a bending operation of the bending portion95is freely turnably disposed. A connection portion of the insertion portion91and the operation portion92is a grasping portion98to be grasped by a user.

The universal cable93extended from the operation portion92is connected with the main body device3through a connector90. The main body device3is connected with the monitor4which displays an endoscope image.

Next, the configuration of the endoscope system1is illustrated inFIG. 21.

In the inside of the insertion portion91of the endoscope2, the detection fiber27which is inserted from a proximal end side to the distal end side along an inner periphery of the insertion portion91and guides the reflected light from the subject is provided. To the incidence portion16which is a distal end of the detection fiber27, the detection optical system46is disposed. When the connector90of the endoscope2is connected to the main body device3, the detection fiber27is connected to a demultiplexer186.

The main body device3is provided with a power source171, a memory172, a controller173, a light source unit174, the drive control unit175, and the detection unit176. The light source unit174is provided with three light sources181a,181band181c, and a multiplexer182.

The drive control unit175is provided with a driver unit177, and the optical fiber scanning apparatus10or the like is driven by the driver unit177.

The power source171supplies power to the controller173or the like. In the memory172, a control program for controlling the entire main body device3or the like is stored.

The controller173reads the control program from the memory172, and controls the light source unit174and the drive control unit175. In addition, the controller173performs control of performing data processing to light intensity signals of the reflected light from the object detected by the detection unit176and displaying the image on the monitor4.

The light sources181a,181band181cof the light source unit174emit the light of respectively different wavelength bands, the light of the wavelength bands of R (red), G (green) and B (blue) for example, to the multiplexer182, based on the control of the controller173. The multiplexer182multiplexes the light of the wavelength bands of R, G and B, and emits it to the optical fiber28.

The driver unit177of the drive control unit175outputs drive signals for causing the distal end of the optical fiber28of the optical fiber scanning apparatus10to perform scanning by a desired scanning method to the magnetic field generation unit20U, based on the control of the controller173. That is, the driver unit177outputs predetermined drive signals to the optical fiber scanning apparatus10so as to drive the distal end of the optical fiber28in a horizontal direction (X axis direction) and a vertical direction (Y axis direction) regarding an insertion axis (Z axis) of the insertion portion91.

The detection fiber27receives the reflected light reflected on a surface of the subject, and guides the received reflected light to the demultiplexer186. The demultiplexer186is a dichroic mirror or the like for example, and demultiplexes the reflected light by each predetermined wavelength band. Specifically, the demultiplexer186demultiplexes the reflected light guided by the detection fiber27into the reflected light of the wavelength bands of R, G and B, and outputs the respective reflected light to detectors187a,187band187c.

The detectors187a,187band187care PD elements which detect light intensity of the reflected light of the wavelength bands of R, G and B respectively or the like. Signals of the light intensity detected in the detectors187a,187band187care respectively outputted to A/D converters188a,188band188c. The A/D converters188ato188crespectively convert the signals of the light intensity outputted from the detectors187ato187cfrom analog signals to digital signals, and output the digital signals to the controller173.

The controller173generates the object image by executing predetermined image processing to the digital signals from the A/D converters188ato188c, and displays the object image on the monitor4.

Note that monochromatic light may be used or a laser beam may be used as the illumination light.

Since the optical scanning type endoscope2has one of the optical fiber scanning apparatuses10and10A to10F at the distal end portion94of the insertion portion91, the distal end portion is small in the diameter and is lowly invasive. In addition, since the optical fiber scanning apparatuses10and10A to10F perform highly accurate scan irradiation, the optical scanning type endoscope2can obtain excellent images. In addition, since the optical scanning type endoscope2can efficiently drive the magnetic field generation unit, the power consumption is low.

The present invention is not limited to the individual embodiments described above, and various modifications, combinations and applications are of course possible without deviating from the scope of the invention.