WO2014054743A1

WO2014054743A1 - Imaging unit

Info

Publication number: WO2014054743A1
Application number: PCT/JP2013/076960
Authority: WO
Inventors: 亮町田
Original assignee: オリンパスメディカルシステムズ株式会社
Priority date: 2012-10-04
Filing date: 2013-10-03
Publication date: 2014-04-10

Abstract

An imaging unit (30) is provided with: objective optical systems (41, 42); an imaging element (45) for capturing an image that is formed by the objective optical systems (41, 42); and a light adjustment device (50) comprising a drive unit (70) that drives an adjustment member (56) for adjusting the light amount, wavelength bandwidth, or focus position of imaging light so that said adjustment member (56) is inserted into and removed from the objective optical systems. The drive unit (70) comprises electromagnetic coils (72, 73) and the axes of the electromagnetic coils (72, 73) are arranged so as to be parallel to the lengthwise direction of an effective image area (I) that is longer in the horizontal direction thereof.

Description

Imaging unit

The present invention relates to an imaging unit in which a member that changes optical performance is inserted into and removed from an imaging optical path by an actuator.

Conventionally, a technique is known in which an optical variable member is disposed on a photographing optical path of an objective optical system to perform aperture adjustment, a zoom function, special observation, and the like. For example, JP-A 2007-289278 discloses a video scope having an imaging unit including an objective optical system, a CCD, and a variable aperture unit.

In this conventional imaging unit, the special light filter is retracted during normal light observation and the variable aperture is inserted. The special light filter is inserted during special light observation. In the special light observation at a far point, a technique is disclosed in which an optimum brightness and observation depth are ensured by retracting the variable aperture and observing the aperture in the open state. The insertion / retraction of the special light dedicated filter and the variable aperture on the photographing optical path is performed by driving control of the filter / variable aperture unit.

However, an actuator such as the filter / variable aperture unit described in JP-A-2007-289278 is disposed in the objective optical system, and drives a plurality of members such as a special light dedicated filter and a variable aperture. The drive mechanism is complicated. Therefore, vignetting may be caused by these structures including the drive mechanism. In addition, the reflected light to the structure may cause flare, ghost, and the like.

Furthermore, the actuator has a problem that the outer diameter of the imaging unit becomes large if a driving mechanism for driving a plurality of members such as a special light filter and a variable diaphragm and a space for retracting them are secured. It was.

Therefore, the present invention has been made in view of the above circumstances, and it is an observation image by an actuator drive mechanism that inserts and removes a member that changes optical performance in an objective optical system without increasing the outer diameter. An object of the present invention is to provide an imaging unit that prevents the occurrence of vignetting, flare, ghost, and the like.

In order to achieve the above object, an imaging unit according to one embodiment of the present invention includes an objective optical system, an imaging element that captures an image formed by the objective optical system, and the amount or wavelength band or in-focus position of imaging light. And an optical adjustment device having a drive unit that drives the adjustment member to adjust the position so as to be inserted into and removed from the objective optical system. The drive unit includes an electromagnetic coil, and the axis of the electromagnetic coil is a horizontally long effective image. It arrange | positions so that it may become parallel to the longitudinal direction of an area | region.

According to the present invention, imaging that prevents the occurrence of vignetting, flare, ghost, and the like in an observation image by an actuator driving mechanism that inserts and removes a member that changes optical performance in an objective optical system without increasing the outer diameter. Units can be provided.

The perspective view which shows the structure of the endoscope apparatus which has the endoscope of 1 aspect of this invention. Sectional view showing the configuration of the imaging unit The exploded perspective view showing the configuration of the light adjusting device Same perspective view of light adjustment device Same as above, top view of light adjustment device Same as above, sectional view of light adjustment device Sectional drawing explaining arrangement | positioning of the light adjustment apparatus in an imaging unit FIG. 7 is a plan view showing the imaging substrate on the light receiving unit side along the line VIII-VIII in FIG. The figure which shows the display area of the picked-up image which projected and displayed the electromagnetic drive source of the light adjusting device similarly The top view which shows the imaging substrate by the side of the light-receiving part of a modification, and shows the display area of the picked-up image which projected and displayed the electromagnetic drive source of the light adjusting device

Hereinafter, an endoscope apparatus provided with the imaging unit of the present invention will be described. In the following description, the drawings based on each embodiment are schematic, and the relationship between the thickness and width of each part, the thickness ratio of each part, and the like are different from the actual ones. It should be noted that the drawings may include portions having different dimensional relationships and ratios between the drawings.

Note that the endoscope in the following description of the configuration will be described by taking a so-called flexible endoscope having an insertion portion flexible for insertion into the digestive organs of the upper or lower part of the living body, but is not limited thereto. In addition, the technique can be applied to a so-called rigid endoscope having a hard insertion portion used for surgery.

(First embodiment)
First, a first embodiment of the present invention will be described with reference to the drawings. 1 is a perspective view showing a configuration of an endoscope apparatus having an endoscope, FIG. 2 is a sectional view showing a configuration of an imaging unit, FIG. 3 is an exploded perspective view showing a configuration of a light adjusting device, and FIG. FIG. 5 is a plan view of the light adjusting device, FIG. 6 is a cross-sectional view of the light adjusting device, FIG. 7 is a cross-sectional view for explaining the arrangement of the light adjusting device in the imaging unit, and FIG. FIG. 9 is a plan view showing the imaging substrate on the light receiving unit side along the line -VIII, FIG. 9 is a diagram showing a display area of a photographed image on which the electromagnetic drive source of the light adjusting device is projected, and FIG. It is a top view which shows the display area of the picked-up image which showed the imaging substrate and projected and displayed the electromagnetic drive source of the light adjusting device.

As shown in FIG. 1, the electronic endoscope system 1 of the present embodiment mainly includes an endoscope 2, a light source device 3, a video processor 4, and a monitor 5. The endoscope 2 includes a long and narrow insertion portion 9, an operation portion 10, and a universal cable 19 that is an electric cable. The insertion portion 9 of the endoscope 2 includes a distal end portion 6, a bending portion 7, and a flexible tube portion 8 in order from the distal end.

The operation section 10 is provided with a bending operation knob 14 for bending the bending section 7 of the insertion section 9 and is provided with

switches

15 and 16 for various endoscope functions. Yes. In the bending operation knob 14, a UD bending operation knob 12 for bending the bending portion 7 in the vertical direction and an RL bending operation knob 13 for bending the bending portion 7 in the left-right direction are superimposed. It is arranged.

The connecting portion between the insertion portion 9 and the operation portion 10 includes a gripping portion 11 that also serves as a gripping portion by the user, and a bend preventing portion provided between the gripping portion 11 and one end of the flexible tube portion 8 of the insertion portion 9. And a treatment instrument channel insertion portion 18 serving as an opening of a treatment instrument channel through which various treatment instruments arranged in the insertion portion 9 are inserted.

The universal cable 19 extended from the operation unit 10 has an endoscope connector 19a that is detachable from the light source device 3 at the extended end. The endoscope 2 according to the present embodiment illuminates from the light source device 3 to the distal end portion 6 by a light guide bundle (not shown) of illumination means disposed in the universal cable 19, the operation unit 10, and the insertion unit 9. It transmits light. Further, the endoscope connector 19a is provided with a coiled coil cable 20 extending, and an electric connector detachably attached to the video processor 4 is provided at an extended end of the coil cable 20.

The video processor 4 is electrically connected to a monitor 5 that displays an endoscopic image, and receives an imaging signal photoelectrically converted by an endoscope imaging unit 30 described later, which is an imaging unit described later of the endoscope 2. The signal is processed and output to the monitor 5 as an image signal. In the electronic endoscope system 1, although not shown, the light source device 3 is provided with an air / water supply function for ejecting air and water from the distal end portion 6 of the insertion portion 9 of the endoscope 2.

Here, the imaging unit 30 of the present invention will be described below based on the drawings.
An endoscope imaging unit (hereinafter simply referred to as an imaging unit) 30 shown in FIG. As shown in FIG. 2, the imaging unit 30 includes a metal and substantially tubular lens frame 31, a unit holding frame 32 fitted outside the lens frame 31, and an outer side behind the unit holding frame 32. And a reinforcing frame 33 fitted therein.

Here, the lens frame 31 is made of a metal such as stainless steel, and constitutes a lens fixing frame that holds the first lens group 41 and the second lens group 42 of the objective optical system. Between the first lens group 41 and the second lens group 42 of the lens frame 31, a light adjusting device 50, which will be described later, provided with a micro actuator is disposed. In addition, the lens frame 31 is fitted by inserting the distal end portion of the unit holding frame 32 to the base end portion.

The unit holding frame 32 holds the optical member 43 at the rear part. The front surface of the cover glass 44 is fixed to the rear surface of the optical member 43 with an optical adhesive. On the rear surface of the cover glass 44, a solid-state image pickup element 45 as an image pickup means as an image sensor such as a CCD or CMOS is fixed by an optical adhesive.

The solid-state imaging device 45 is electrically connected to the imaging substrate 46. The optical member 43, the cover glass 44, the solid-state imaging device 45, and the imaging substrate 465 held by the unit holding frame 32 are covered with the reinforcing frame 33. The periphery of the solid-state imaging device 45 and the imaging substrate 46 is covered with a filler (not shown) such as an adhesive in the reinforcing frame 33 for moisture prevention, insulation and the like.

In the imaging unit 30 configured as described above, photographing light (subject image) of the optical axis O that enters the first lens group 41 and the second lens group 42 is imaged by the light receiving unit of the solid-state imaging device 45. It has become so. The solid-state imaging device 45 photoelectrically converts the photographic light and outputs imaging data of the subject to the imaging substrate 46. And the imaging board | substrate 46 processes electrically imaging data appropriately, and outputs it to the communication cable (not shown) electrically connected. This communication cable is inserted and arranged in the endoscope 2, and the video processor 4 as an external device shown in FIG. 1 and an electrical connector provided on the coil cable 20 extending from the endoscope connector 19 a are provided. Electrically connected.

Here, the light adjusting device 50 as the light adjusting means will be described below based on the drawings.
As shown in FIGS. 3 to 5, the light adjustment device 50 includes a substrate 51 in which an optical opening 52 is formed, a substrate 53 in which an optical opening 54 is formed, and a plate-like light adjustment in which an optical opening 55 is formed. A mechanism 56, two

restriction portions

61 and 62 that are convexly formed on one surface of the substrate 53 and restrict the movement of the light adjustment mechanism 56, and an electromagnetic drive source 70 as an electromagnetic drive means for moving the light adjustment mechanism 56. I have.

In this light adjusting device 50, the substrate 51 and the substrate 53 are plate bodies having

disc portions

51a and 53a having substantially the same diameter, and an optical aperture 52 and an optical aperture are formed at the centers of the

disc portions

51a and 53a. An optical aperture 54 serving as a stop is provided. The optical aperture 55 of the light adjusting mechanism 56 has a predetermined aperture diameter as an optical diaphragm based on the objective lens. The optical aperture 54 has an aperture diameter smaller than that of the optical aperture 55 of the light adjusting mechanism 56 and the optical aperture 52 of the substrate 51.

In addition, the board | substrate 51 and the board | substrate 53 have the

rectangular parts

51b and 53b extended from one outer peripheral part of the

disk parts

51a and 53a. These

rectangular portions

51b and 53b are opposed to each other when they are overlapped (stacked) together to constitute a retracting portion into which the light adjustment mechanism 56 enters. Further, the rectangular portion 53b of the substrate 53 has a convex portion 52c that forms a gap for allowing the light adjusting mechanism 56 to enter the edge portion by contacting the rectangular portion 51b of the substrate 51 when the rectangular portion 51b overlaps. have. Note that the retreating unit including the

rectangular units

51 b and 53 b is disposed in a dead space in the imaging unit 30.

Rotating shaft holes 63 and 64 are respectively formed in the

substrates

51 and 53 at positions corresponding when the optical aperture 52 and the optical aperture 54 are laminated together. The light adjustment mechanism 56 disposed between the

substrates

51 and 53 is provided with a magnetic rotating shaft member 59. Both ends of the rotary shaft member 59 are rotatably inserted into the rotary shaft holes 63 and 64, respectively. Further, a spacer member 65 is disposed between the substrate 51 and the substrate 53 in order to form a gap for allowing the light adjusting mechanism 56 to freely rotate.

In the light adjusting mechanism 56 here, an optical filter 55 a is provided in the optical aperture 55. The optical filter 55a cuts light of a specific wavelength from normal observation light when performing special observation, for example, fluorescence observation. The light adjusting mechanism 56 is not limited to a mechanism for inserting / removing the optical filter 55a onto / from the photographing optical path, and may be a zoom mechanism in which a zoom lens is disposed in the optical aperture 55. Further, the optical aperture 55 itself is provided. A variable aperture mechanism having an optical variable aperture may be used.

The electromagnetic drive source 70 of the light adjusting mechanism 56 includes a U-shaped yoke member 71 (yoke) as a structure and two winding coil portions (electromagnetic coil portions) wound around two arm portions of the yoke member 71. ) 72 and 73, and disposed on the substrate 51 in the outer region of the imaging light beam focused by the first and

second lens groups

41 and 42. The winding

coil portions

72 and 73 constitute a drive portion, and are wound at both ends of the yoke member 71 so that both

end portions

74 and 75 of the yoke member 71 are exposed. Both

end portions

74 and 75 of the yoke member 71 are provided at positions facing each other with the rotary shaft member 59 interposed therebetween.

As shown in FIG. 6, the light adjustment device 50 configured as described above is configured such that the light adjustment mechanism 56 rotates the rotation shaft member 59 using the electromagnetic drive source 70, thereby causing the central axis of the rotation shaft member 59 to rotate. Is rotated around the center of rotation. That is, by applying a current to the electromagnetic drive source 70, the rotating shaft member 59 is rotated by the magnetic force generated from the both

end portions

74 and 75 of the yoke member 71, and the light adjustment mechanism 56 is superimposed on the optical aperture 52 and the optical aperture 54. The first stationary position A where the optical filter 55a is disposed on the photographing optical path, and the second stationary position where the optical filter 55a of the light adjusting mechanism 56 enters the retracting portion by the

rectangular portions

51b and 53b and is removed from the photographing optical path. The position B can be moved mutually.

In the light adjusting device 50 here, since the light adjusting mechanism 56 includes the optical filter 55a, the optical filter 55a of the light adjusting mechanism 56 is moved to the first stationary position A on the photographing optical path. Thus, the fluorescence observation can be performed here, and the optical filter 55a can be switched to the second stationary position B that is removed from the photographing optical path so that the normal light observation can be performed.

As described above, the endoscope 2 according to the present embodiment can perform normal observation and fluorescence observation with one objective optical system even if it does not include two objective optical systems (imaging unit 30) for normal observation and fluorescence observation. It has a configuration that can be switched and observed. As described above, the imaging unit 30 of the endoscope 2 is configured so that the normal observation and the fluorescence observation without parallax can be performed simultaneously by the two objective optical systems by switching by the light adjustment device 50. Yes.

If the light adjustment mechanism 56 is a zoom mechanism in which a zoom lens is disposed in the optical aperture 55 as described above, the light adjustment mechanism 56 is switched between the first stationary position A and the second stationary position B. By moving, the zoom or tele state can be switched. Further, as described above, when the light adjustment mechanism 56 is a variable diaphragm mechanism having the optical aperture 55 as an optical variable diaphragm, the light adjustment mechanism 56 is switched between the first stationary position A and the second stationary position B. By doing so, it is possible to change the depth of field by adjusting the amount of light.

Here, the arrangement configuration of the light adjustment device 50 in the imaging unit 30 will be described below.
As shown in FIG. 7, the light adjustment device 50 is disposed between the first lens group 41 and the second lens group 42. The light adjusting device 50 is arranged so that the second substrate 53 on which an optical aperture 54 serving as an optical diaphragm (brightness diaphragm) is formed is on the first lens group 41 side on the object point side. In other words, the electromagnetic drive source 70 of the light adjusting device 50 is arranged so as to be on the second lens group 42 side on the imaging side.

That is, in order to reduce the size of the light adjusting device 50, it is preferable that the diameter of the light beam of the photographing light (light beam) passing through is as small as possible. For this reason, the optical aperture 54 of the second substrate 53 functions as an aperture stop, and an optical adjustment mechanism 56 having an optical filter 55a in the vicinity of the aperture stop and an electromagnetic as a minute actuator that drives the optical adjustment mechanism 56. The drive source 70 is arranged.

Further, the electromagnetic drive source 70 includes a yoke member 71 and two winding

coil portions

72 and 73 as a driving portion for electromagnetically driving the light adjusting mechanism 56, and these yoke member 71 and winding

coil portions

72 and 73. Is on the object point side, it is easy to enter or reflect the incident light of the photographing light (optical axis O), which may cause vignetting, flare, ghosting, etc. in the observed image. Therefore, the electromagnetic drive source 70 of the present embodiment is arranged so as to be on the second lens group 42 side on the imaging side.

As shown in FIG. 8, in the image R in which the imaging light beam focused by the

lens groups

41 and 42 is imaged on the light receiving unit 45a of the solid-state image sensor 45, the outer peripheral portion where distortion or the like occurs is masked by image processing. The image area I, which is an effective image area to be cut out, has a horizontally long shape in which the image height H1 in the Y direction in the drawing is smaller than the image height H2 in the X direction in the drawing (H1 <H2). Is an octagon obtained by cutting off a corner of a rectangle having a short length and a long horizontal direction (left and right direction). That is, the image area I has an image height H1 that is the lowest in the vertical direction, and is an effective image area displayed on the monitor 5. Here, the up, down, left, and right directions are image directions displayed on the monitor 5.

As shown in FIG. 9, the winding

coil portions

72 and 73 of the electromagnetic drive source 70 are substantially symmetric with respect to the center of the image area I (shooting optical axis O), and the coil axis is substantially parallel to the X direction. It is arranged to become.

Further, the cutout shape masked by the image processing is not limited to the octagon in the image region I, and the image region I is imaged on any shape, for example, on the light receiving unit 45a of the solid-state image sensor 45 as shown in FIG. Only the upper and lower sides of the image R in the Y direction may be masked. Also in this case, the winding

coil portions

72 and 73 are arranged so that the axes of the respective coils are substantially parallel to the longitudinal direction (X direction) of the image region I.

As described above, in the imaging unit 30 of the present embodiment, even if the light adjustment device 50 that drives the optical filter 55a is disposed between the first and

second lens groups

41 and 42, the light adjustment is performed. The first and

second lens groups

41 and 42 are arranged so that the drive mechanism of the device 50, the electromagnetic drive source 70 as a structure here, does not enter the photographing light flux in the direction of the image height H1 of the image area I. Is arranged so as to be an area outside the imaging light beam that is focused by the lens, so that the occurrence of vignetting, flare, ghost, etc. on the observation image can be prevented.

Furthermore, the light adjustment device 50 arranges the retracting portion of the light adjustment mechanism 56 in the dead space in the imaging unit 30. For example, since the space can be effectively utilized if arranged in the diagonal direction in FIGS. 9 and 10, it is possible to prevent the outer diameter of the imaging unit 30 from increasing. In addition, the imaging unit 30 can perform normal observation and fluorescence observation with one objective optical system by switching the optical filter 55a on the imaging optical path by the light adjustment device 50, so simultaneous observation without parallax can be performed. Yes. As a result, since the imaging unit 30 can be reduced in diameter, the distal end portion 6 of the endoscope 1 can be reduced in size, and the insertion portion 9 can be reduced in diameter.

It should be noted that the invention described in the above-described embodiment is not limited to the embodiment and modification examples, and various modifications can be made without departing from the scope of the invention in the implementation stage. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.
For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the described requirements can be deleted if the stated problem can be solved and the stated effect can be obtained. The configuration can be extracted as an invention.

This application is filed on the basis of the priority claim of Japanese Patent Application No. 2012-222236 filed in Japan on October 4, 2012, and the above contents include the present specification, claims, and It is cited in the drawing.

Claims

An objective optical system;
An image pickup device for picking up an image formed by the objective optical system;
A light adjustment device having a drive unit for driving an adjustment member that adjusts the light amount or wavelength band of the photographing light or the focus position so as to be inserted into and removed from the objective optical system;
With
The drive unit has an electromagnetic coil, and an axis of the electromagnetic coil is arranged so as to be parallel to a longitudinal direction of a horizontally long effective image region.
The imaging unit according to claim 1, wherein the adjusting member is disposed in the vicinity of an aperture stop.
3. The imaging unit according to claim 2, wherein the brightness diaphragm is provided in the light adjustment device.
4. The image pickup unit according to claim 2, wherein the brightness diaphragm is disposed on an object point side of the adjustment member.
The imaging unit according to any one of claims 1 to 4, wherein the electromagnetic coil is disposed symmetrically with respect to an optical axis of the photographing light focused by the objective optical system.
The imaging unit according to any one of claims 1 to 5, wherein the driving unit is disposed on the imaging element side of the adjustment member.
The image pickup unit according to any one of claims 1 to 6, wherein the light adjusting device includes a retracting portion into which the adjusting member that is out of the photographing optical path enters.
The imaging unit according to any one of claims 1 to 7, wherein the adjustment member includes an optical filter, a zoom lens, or a variable diaphragm.