JP2005312936A - Electronic endoscope system, lighting device for electronic endoscope system, and light controller for electronic endoscope system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic endoscope system which eliminates the need of a mechanism for changing an inter-axis distance and easily adjusts light with the use of a rotary shutter which has a smaller outer diameter and is well-balanced in rotation, and to provide a lighting device for the electronic endoscope system, and a light controller for the electronic endoscope system. <P>SOLUTION: The lighting device for the electronic endoscope system includes: a light source; and a rotary shutter group where a rotational axis is arranged in parallel with the optical axis of the light source and which intercepts incident illuminating light emitted from the light source and emits the incident illuminating light toward a light guide. The rotary shutter group includes a plurality of the rotary shutters which are integrally rotated and each of which has a light shielding part and an aperture part. The plurality of rotary shutters are relatively rotated each other to change the opening angle of each aperture part as a whole so as to adjust the amount of light emission. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electronic endoscope, and more particularly to an electronic endoscope light source device and an electronic endoscope dimmer using a plurality of rotary shutters.

In a conventional electronic endoscope, an endoscope recording apparatus disclosed in, for example, Japanese Patent Laid-Open No. 62-69222 has been proposed in order to perform appropriate light control. This apparatus has a rotary shutter provided with a rotation shaft capable of changing an inter-axis distance from an irradiation optical axis of an endoscope light source. This rotary shutter has a shape that produces a difference in peripheral speed at each part in the radial direction when it rotates, or changes its aperture ratio, and this difference in peripheral speed can be reduced by changing the inter-axis distance. Dimming is performed using it.
JP-A-62-69222 Japanese Patent Publication No. 7-85132

In the apparatus described in Japanese Patent Laid-Open No. 62-69222, although dimming is possible, the configuration of the rotary shutter is complicated, and the distance between the rotary shutter and the irradiation optical axis of the endoscope light source is set. A mechanism to change is necessary, and manufacturing is costly and troublesome. Furthermore, to realize this configuration, the outer diameter of the rotary shutter must be several times the luminous flux of incident light, and the rotary shutter must be enlarged. Also, if the shape of the rotary shaft is asymmetric with respect to the rotation axis in order to change the aperture ratio at each part of the rotary shutter, the center of rotation and the center of gravity will not match and the balance during rotation will be lost, and the illumination light will be emitted In addition, the rotary shutter and members disposed around the rotary shutter may be damaged.

  In order to solve the above-described problems, in the light source device for an electronic endoscope of the present invention, the light source and the rotation axis are arranged in parallel with the optical axis of the light source so as to block the illumination light incident from the light source or to the light guide. A rotary shutter group that emits light, and the rotary shutter group is integrally rotatable and includes a plurality of rotary shutters each having a light-shielding portion and an opening, and the plurality of rotary shutters are mutually connected. The amount of emitted light is adjusted by changing the opening angle of the opening of the entire rotary shutter group by relative rotation.

  A dimmer for an electronic endoscope according to the present invention includes a rotary shutter group in which a rotation axis is arranged in parallel with an optical axis of a light source, and shields illumination light incident from the light source or emits it toward a light guide. The shutter group is integrally rotatable and has a plurality of rotary shutters each having a light shielding portion and an opening, and the plurality of rotary shutters are rotated relative to each other so that the opening of the rotary shutter group as a whole is rotated. The amount of emitted light is adjusted by changing the opening angle.

An electronic endoscope according to the present invention includes an operation unit, an insertion unit that extends from the operation unit and is inserted into an observation target, a light guide that is inserted into the operation unit and the insertion unit, and the distal end of which extends to the distal end of the insertion unit. A light source device that makes illumination light incident on the light guide. The light source device has a light source and a rotation axis arranged in parallel with the optical axis of the light source, and shields the illumination light incident from the light source or to the light guide. A rotary shutter group that emits light, and the rotary shutter group is integrally rotatable and includes a plurality of rotary shutters each having a light-shielding portion and an opening, and the plurality of rotary shutters are mutually connected. The amount of emitted light is adjusted by changing the opening angle of the opening of the entire rotary shutter group by relative rotation.

  The rotary shutter group is rotated as a unit by a first motor, and the plurality of rotary shutters are preferably rotated relative to each other when one of the rotary shutters is rotated by a second motor separate from the motor. .

  The first motor may be a DC motor, and the second motor may be an ultrasonic motor.

  The opening angle is preferably changeable within a range of 0 to 90 degrees.

  The rotation shafts of the first motor and the second motor may be arranged concentrically.

  Each of the plurality of rotary shutters includes a central circular portion, and a plurality of rotationally symmetric arc-shaped light shielding portions and a plurality of rotationally symmetric arc-shaped openings disposed at equal angular intervals with respect to the rotation axis of the rotary shutter. It is preferable.

  According to the present invention, an electronic endoscope and an electronic endoscope that do not require a mechanism for changing an inter-axis distance, can be easily dimmed by a rotary shutter that has a small outer diameter and is balanced during rotation. Light source device and electronic endoscope light control device can be provided.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, an electronic endoscope 1 according to the present embodiment includes an operation unit 11 held by an operator, an elongated and flexible insertion unit 12 extending outward from the operation unit 11, A light guide 20 that emits illumination light from the distal end of the insertion portion 12 to the outside, and a light source device 30 that is connected to the operation portion 11 via a connection connecting tube 13 are provided. The light guide 20 is inserted into the insertion portion 12, the operation portion 11, and the connection connecting tube 13 and connected to the light source device 30. A lamp (light source) 31 is disposed in the light source device 30, and illumination light emitted from the light source device 30 passes through the light guide 20 and is emitted from the distal end of the insertion portion 12 to the outside. The reflected light from the observation site due to the illumination light enters the insertion portion 12 from the objective optical system 15 disposed at the distal end of the insertion portion 12 and is accumulated as a charge in the CCD (solid-state imaging device) 16 (see FIG. 2). . Here, the objective optical system 15 and the CCD 16 constitute an image pickup means, and the CCD 16 is an interlace drive image pickup element that handles one frame divided into an odd field and an even field. All pixel data of the CCD 16 is divided into odd fields and even fields, transferred to a register (image data storage means) 17, developed into one frame by an image processing device 18 connected thereto, and displayed on a display device 19. (FIG. 2).

In addition to the lamp 31, the light source device 30 includes a rotary shaft 40a parallel to the optical axis 31a of the lamp 31, and a rotary shutter group 40 as a dimming device capable of dimming and blocking illumination light emitted from the lamp 31; The condensing lens 34 that condenses the light emitted from the lamp 31 and enters the light guide 20, the motor (first motor) 33 that rotates the rotary shutter group 40 together, and the rotary shutter group 40 are configured. And an ultrasonic motor (second motor) 36 that rotates the second rotary shutter 42 relative to the first rotary shutter 41.

  As shown in FIG. 3A, the group of rotary shutters 40 includes a first rotary shutter 41 and a second rotary shutter 42 having the same outer shape. The first rotary shutter 41 shown in FIG. 3 (b) is a target (equal angular interval) with respect to the rotation shaft 41b, leaving a central circular portion 41a out of a disc of aluminum radius R41 formed by molding. It consists of openings 41c and 41d formed by cutting out arc portions having two central angles of 90 °, and light-shielding portions 41e and 41f corresponding to the two arc portions having a remaining central angle of 90 °. On the other hand, the second rotary shutter 42 shown in FIG. 3 (c) is an object with respect to the rotating shaft 42b, leaving a central circular portion 42a out of the aluminum disc R42 (R42 <R41) formed by molding. Opening portions 42c and 42d formed by cutting out arc portions having two central angles 90 ° (at equal angular intervals), and light shielding portions 42e and 42f corresponding to the two arc portions having the remaining central angle 90 ° of the disc. And consist of Here, the radii R41 and R42 are preferably equal to or larger than the diameter of the luminous flux of the illumination light incident on the rotary shutter group 40 from the lamp 31, and R41 = R42 may be satisfied if this condition is satisfied. R41 <R42 may be sufficient. Further, in the first rotary shutter 41 and the second rotary shutter 42 shown in FIG. 3, the disc is divided into four equal parts around the rotation shaft 41b and the rotation shaft 42b, thereby forming an opening portion and a light shielding portion having a central angle of 90 °. However, it may be an arc having a central angle other than 90 °, and the shapes of the first rotary shutter 41 and the second rotary shutter 42 may be different. Further, the rotary shutter group 40 may be constituted by three or more rotary shutters.

  As shown in FIG. 3A, the first rotary shutter 41 and the second rotary shutter 42 configured as described above are arranged so that the rotation shaft 41b and the rotation shaft 42b coincide with each other and are relatively rotatable. Mounting. The first rotary shutter 41 is arranged so that the light shielding part 41e and the light shielding part 41f are within the first quadrant and the third quadrant on the coordinate plane composed of the X axis (horizontal direction) and the Y axis (vertical direction). On the other hand, when the second rotary shutter 42 is disposed such that the light shielding part 42e and the light shielding part 42f are offset counterclockwise by an angle α (degrees) with respect to the light shielding part 41e and the light shielding part 41f, the opening 41c and A part of the opening 41d is shielded by the light shielding part 42e and the light shielding part 42f. Accordingly, the openings 40c and 40d constituting the rotary shutter group 40 are objects with respect to the rotation axis 40b, and have the same shape with a center angle (opening angle) θ cut out of an arc of (90−α) degrees. Become. The central angle θ can be set in a range of 0 to 90 degrees by relatively rotating the first rotary shutter 41 and the second rotary shutter 42. When θ is 0 degree, the rotary shutter group 40 blocks all incident light.

  As shown in FIG. 4, the first rotary shutter 41 and the second rotary shutter 42 are mounted on an ultrasonic motor 36 that can rotate relative to each other. Specifically, the first rotary shutter 41 is fixed to the base 37 a of the stator 37 of the ultrasonic motor 36, and the second rotary shutter 42 is fixed to the circular rotating portion 38 a of the rotor 38 of the ultrasonic motor 36. The base portion 37a passes through the circular portion 41a, and the circular rotating portion 38a passes through the circular portion 42a concentrically. In addition to the circular rotating portion 38a, the rotor 38 is disposed on the outer periphery of a shaft portion 37d formed so as to extend on the rotating shaft 37c of the stator 37, and the outer periphery is fixed to the inner periphery of the circular rotating portion 38a. A ring-shaped outer bearing 38b is provided. A ring-shaped piezoelectric element group 37b is inserted into the base portion 37a, and the piezoelectric element group 37b is disposed so as to be in contact with the circular rotating portion 38a. In this configuration, when a current is applied to the piezoelectric element group 37b, the piezoelectric element group 37b is deformed according to the amount of the current, and the circular rotating portion 38a rotates around the rotation axis 38a1 along with the deformation, The first rotary shutter 41 and the second rotary shutter 42 rotate relative to each other. On the other hand, in a state where no current is applied to the piezoelectric element group 37b, when the first rotary shutter 41 is rotated, the second rotary shutter 42 is also rotated integrally therewith.

  The stator 37 includes a shaft insertion recess 37e that is recessed so as to extend in the direction of the rotation shaft 37c. When the shaft portion 33b of the motor 33 (for example, a DC motor or an AC motor) is bonded and fixed in the shaft insertion recess 37e so that the rotation shaft 33a and the rotation shaft 37c coincide with each other, the stator 37 and the first shaft are driven by the motor 33. The rotary shutter 41 can be rotated around the rotation shaft 37c and the rotation shaft 41b. At this time, when no current is applied to the piezoelectric element group 37b, the second rotary shutter 42 also rotates integrally with the first rotary shutter 41. When current is applied to the piezoelectric element group 37b, the application time or The second rotary shutter 42 rotates relative to the first rotary shutter 41 by an amount corresponding to the amount of applied current. Therefore, by rotating the second rotary shutter 42 relative to the first rotary shutter 41 by applying a predetermined time or a predetermined amount of current to the piezoelectric element group 37b while the first rotary shutter 41 is rotated by the motor 33. Since the amount of light emitted from the rotary shutter group 40 can be adjusted by changing the opening angle of the opening 40c and the opening 40d, it is possible to adjust the illumination light. The application of current to the piezoelectric element group 37 b is performed under the control of the controller 35 provided in the light source device 30.

  Next, an actual imaging display operation of the observation site will be described with reference to FIG. Prior to the observation, the insertion portion 12 is inserted into the body of the patient to be observed, and the tip thereof is directed to the observation site. When a start button (not shown) is pressed in this state, illumination light is emitted from the lamp 31, the observation region is illuminated via the light guide 20, and the state of the observation region is displayed on the display device. At this time, the luminance of the observation site is detected by the luminance sensor 21. If the luminance is low, the luminance is such that the central angle (opening angle) of the opening 40c and the opening 40d is 90 degrees or close to 90 degrees. Is higher, the controller 35 rotates the second rotary shutter 42 relative to the first rotary shutter 41 so that the central angle of the opening 40c and the opening 40d is close to 0 degrees.

  FIGS. 5A to 5D show the irradiation light amount to the observation site, the accumulated charge amount to the CCD 16, the transfer charge amount to the register 17, and the video output timing when the luminance of the observation site is constant. Although shown, there is no difference in timing even when the luminance of the observation region is not constant.

  In this embodiment, the rotary shutter group 40 rotates once in 1/30 seconds, and the observation site is illuminated for a time corresponding to the opening angles of the opening 40c and the opening 40d in one rotation (light emission period). For example, when the opening angle of the opening 40c and the opening 40d is 90 degrees, light emission is performed for each 1/120 second. Illumination light is blocked during periods other than the light emission period of the opening 40c and the opening 40d. For example, when the opening angle of the opening 40c and the opening 40d is 90 degrees, the light shielding period of 1/120 seconds and the light emission period of 1/120 seconds are produced while the rotary shutter group 40 rotates once. Appears twice each time. (FIG. 5 (a)). As described above, in the rotary shutter group 40 of the present embodiment, since there are two light emission periods and two light-shielding periods during one rotation, a desired image can be obtained by driving at a speed half the normal moving image rate. be able to. Reflected light from the observation site due to light emission is divided into odd fields (corresponding to cyan and yellow data in this embodiment) and even fields (corresponding to magenta and green data) every 1/30 seconds in accordance with the light emission timing. Separately, both frames are continuously stored as charges in the CCD 16 (FIG. 5B). Since the odd and even fields are continuously accumulated in this way, there is less possibility of blurring in the image when the frames are combined later.

In the light shielding period following the light emission from the opening 40c or the opening 40d, the odd-numbered pixel data is transferred from the CCD 16 to the register 17 (FIG. 5C). This data transfer is started when the luminance sensor 21 detects that the illumination light from the lamp 31 is blocked, and based on this, the controller 35 outputs a signal instructing the transfer start to the register 17.

When the odd field data transfer is completed, the even field pixel data is transferred from the CCD 16 to the register 17. On the other hand, when the light shielding period ends, the light emission period starts again. The data transfer in the light emission period and the even field starts at the same time, but the accumulation in the CCD 16 by the light emission is performed in the order of the odd field and the even field. Since they are sequentially performed, new accumulation of even-field pixel data is performed after the previous even-field data is transferred.

  The accumulation of the odd-numbered field and even-numbered field data in the CCD 16 and the transfer to the register 17 are sequentially repeated in the light emission period or the light shielding period. When the transfer of all the pixel data of the odd field and the even field obtained by one light emission to the register 17 is finished, this data is immediately read out to the image processing device 18 and developed into one frame, and is displayed on the display device 19. Is displayed (FIG. 5D). Such readout of the pixel data is performed at the start of the light shielding period, and is not overwritten by the transfer of the next accumulated data. Further, the same image is continuously displayed until the start of the next light shielding period, and is updated to the next image as the light shielding period starts. Thus, since one frame is synthesized using all pixel data, a high-quality image can be displayed.

  In the electronic endoscope 1 of the present embodiment, when the user operates the capture button 22 (see FIG. 2) connected to the image processing apparatus 18 (FIG. 5 (e)), the image processing apparatus 18 without delay. Stops outputting the display image signal to the display device 19, and the image displayed on the display device 19 is maintained (frozen) as the currently displayed image (FIG. 5 (f)). Even after the capture button 22 is operated, the data in the register 17 continues to be read out to the image processing device 18. When the capture button 22 is operated again, the image processing device 18 displays the display image on the display device 19. The signal output is resumed and the latest image is displayed on the display device 19.

Although the present invention has been described with reference to the above embodiment, the present invention is not limited to the above embodiment, and can be improved or changed within the scope of the purpose of the improvement or the idea of the present invention.

It is the schematic which shows the internal structure of the electronic endoscope which concerns on embodiment of this invention. It is a block diagram which shows the structure of the electronic endoscope which concerns on embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a top view which shows notionally the structure of the rotary shutter which concerns on embodiment of this invention, Comprising: (a) is the state which united the 1st rotary shutter and the 2nd rotary shutter so that relative rotation was mutually possible, (b) Is a plan view showing the configuration of the first rotary shutter, and (c) is a plan view showing the configuration of the second rotary shutter. It is a figure which shows the structure of the rotary shutter group which concerns on embodiment of this invention, a motor, and an ultrasonic motor. It is a timing chart which shows operation | movement of the electronic endoscope which concerns on embodiment of this invention.

Explanation of symbols

1 Electronic endoscope 15 Objective optical system (imaging means)
16 CCD (imaging means)
17 register (image data storage means)
18 Image processing device 19 Display device 20 Light guide 30 Light source device 31 Light source 31a Optical axis 33 Motor (first motor)
36 Ultrasonic motor (second motor)
40 Rotary shutter group 40a Rotating shaft 41 First rotary shutter 42 Second rotary shutter

Claims (12)

A light source;
A rotary shutter group in which a rotation axis is arranged in parallel with the optical axis of the light source, and shields illumination light incident from the light source or emits it toward a light guide;
With
The rotary shutter group is integrally rotatable and has a plurality of rotary shutters each having a light shielding portion and an opening,
A light source device for an electronic endoscope that adjusts the amount of emitted light by rotating the plurality of rotary shutters relative to each other to change the opening angle of the opening as the entire rotary shutter group. The rotary shutter group rotates as a unit by a first motor, and the plurality of rotary shutters rotate relative to each other when one of the rotary shutters is rotated by a second motor separate from the motor. Item 2. A light source device for an electronic endoscope according to Item 1. The light source device for an electronic endoscope according to claim 2, wherein the first motor is a DC motor and the second motor is an ultrasonic motor. A rotary shaft is arranged in parallel with the optical axis of the light source, and includes a rotary shutter group that blocks the illumination light incident from the light source or emits it toward the light guide,
The rotary shutter group is integrally rotatable and has a plurality of rotary shutters each having a light shielding portion and an opening,
A dimming device for an electronic endoscope, wherein the emitted light quantity is adjusted by rotating the plurality of rotary shutters relative to each other to change the opening angle of the opening as the entire rotary shutter group. The rotary shutter group rotates as a unit by a first motor, and the plurality of rotary shutters rotate relative to each other when one of the rotary shutters is rotated by a second motor separate from the motor. Item 5. A light control device for an electronic endoscope according to Item 4. The electronic endoscope light control device according to claim 5, wherein the first motor is a DC motor, and the second motor is an ultrasonic motor. An operation unit;
An insertion portion extending from the operation portion and inserted into the observation target;
A light guide that is inserted into the operation portion and the insertion portion, and whose tip extends to the tip of the insertion portion;
A light source device that makes illumination light incident on the light guide;
Have
The light source device includes a light source, and a rotary shutter group whose rotation axis is arranged in parallel with the optical axis of the light source and shields illumination light incident from the light source or emits it toward a light guide. The shutter group is integrally rotatable and has a plurality of rotary shutters each having a light-shielding portion and an opening. By rotating the plurality of rotary shutters relative to each other, the rotary shutter group as a whole An electronic endoscope characterized in that the amount of emitted light is adjusted by changing the opening angle of the opening. The rotary shutter group rotates as a unit by a first motor, and the plurality of rotary shutters rotate relative to each other when one of the rotary shutters is rotated by a second motor separate from the motor. Item 8. The electronic endoscope according to Item 7. The electronic endoscope according to claim 8, wherein the first motor is a DC motor, and the second motor is an ultrasonic motor. The light source device for an electronic endoscope according to claim 1, wherein the opening angle can be changed within a range of 0 to 90 degrees. The light source device for an electronic endoscope according to claim 2, wherein rotation axes of the first motor and the second motor are arranged concentrically. Each of the plurality of rotary shutters is
A central circular part,
2. The light source device for an electronic endoscope according to claim 1, further comprising: a plurality of rotationally symmetric arc-shaped light shielding portions and a plurality of rotationally symmetric arc-shaped openings disposed at equal angular intervals with respect to the rotation axis of the rotary shutter.

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