JP6456544B1 - Endoscope device - Google Patents

Abstract

To provide an endoscope apparatus that allows a photographer to acquire a photographed image having an arbitrary shift amount and meet the demand for downsizing.
[Solution]
An optical lens, an image sensor disposed on the optical axis of the optical lens, and a drive unit that relatively moves the optical lens and the image sensor so that the optical axis of the image sensor is deviated from the optical axis of the optical lens. And an endoscope apparatus in which a closed optical path space is formed between the optical lens and the imaging device.
[Selection] Figure 2

Description

  The present invention relates to an endoscope apparatus having a shift function in order to widen an observation range.

  Conventionally, endoscope apparatuses have been used in the medical and industrial fields. An endoscope apparatus is used for an operator to observe a desired part of an object that is difficult to observe directly by bending a probe portion of the endoscope apparatus.

  However, it may be difficult to bend the probe portion depending on the size or shape of the object and direct the probe portion to a desired site.

  In addition, when shooting with a camera, video camera, etc., the distortion of the captured image of the subject is corrected by shifting the optical axis of the optical system in the vertical direction with respect to the optical axis of the imaging means that is the imaging plane. Shifting (or tilting) processing is performed.

  For example, Patent Document 1 discloses a shift lens system used for a so-called silver salt camera. The shift lens system includes a front lens group and a rear lens group, and corrects distortion by shifting the whole or a part of the rear lens group in a direction perpendicular to the optical axis.

  Japanese Patent Application Laid-Open No. 2004-228561 discloses an imaging unit that captures an image of a subject to obtain image data, a storage control unit that stores the image data obtained by the imaging unit in a predetermined form as an image data file, and a memory card. Reproduction control means for reproducing the image data stored in the image data, and image data processing means for synthesizing the image data from the imaging means and the image data from the reproduction control means to generate image data and store it in a memory card And display control means for displaying the image data from the imaging means on the LCD and simultaneously displaying the image data from the reproduction control means on the LCD or displaying the image data from the image data processing means on the LCD. A digital camera is disclosed. In this digital camera, when a panoramic image is generated from a plurality of the image data stored in the storage medium, a correction process is performed on the connected image data.

  Therefore, it is conceivable to incorporate the configuration of Patent Document 1 and Patent Document 2 in an endoscope apparatus and provide a shift function in the endoscope apparatus.

Japanese Patent Laid-Open No. 4-253041 JP 2001-309212 A

  Incorporating a shift lens system having a shift function in the silver salt camera disclosed in Patent Document 1 described above into an endoscope apparatus is difficult in an endoscope apparatus that is required to be downsized. Further, since Patent Document 2 is an image pickup apparatus that performs tilt correction only when a plurality of images are combined in a panoramic shape, it is difficult to meet the demand for a photographer to acquire a shot image with an arbitrary shift amount.

  The present invention has been made in view of such circumstances. That is, an object of the present invention is to provide an endoscope apparatus in which an operator can obtain a captured image having an arbitrary shift amount and can be downsized.

  In order to solve the above-described problems and achieve the object, a first aspect of an endoscope apparatus according to the present invention includes an optical lens, an image sensor disposed on an optical axis of the optical lens, and the optical lens. Driving means for moving the optical lens and the image sensor relative to each other so that the optical axis of the image sensor deviates from the optical axis, and a closed optical path space is provided between the optical lens and the image sensor. Is formed.

  According to the second aspect of the endoscope apparatus of the present invention, in the endoscope apparatus according to the first aspect, the optical path space is defined by a bellows member.

  Moreover, according to the 3rd aspect of the endoscope apparatus of this invention, it is the endoscope apparatus of the said 1st or 2nd aspect, Comprising: The side surface of the said optical lens is light for preventing light reflection. Covered with anti-reflective material.

  According to a fourth aspect of the endoscope apparatus of the present invention, the endoscope apparatus according to any one of the first to third aspects, wherein the optical lens is asymmetric with respect to an optical axis thereof. Has a shape.

  According to the present invention, by using an optical lens having an astigmatic shape, the relationship between the distortion amount and the shift amount is calculated based on the first image information and the second image information, and an arbitrary shift amount is obtained. By generating the image information, it is possible to provide an endoscope apparatus that has a shift function and can be miniaturized.

(A) is a schematic perspective view of the endoscope apparatus which concerns on embodiment, (b) is a schematic perspective view which shows the front-end | tip part of the endoscope apparatus shown to Fig.1 (a), (c). FIG. 3 is a perspective view of a second lens group. It is a schematic cross section which shows the endoscope apparatus which concerns on embodiment along an optical axis, (a) shows the matching position where the optical axis of a 1st and 2nd lens group and the optical axis of an image pick-up element correspond. , (B) show non-alignment positions where the optical axes of the first and second lens groups and the optical axis of the image sensor are shifted. It is a schematic diagram which shows typically LCD which displays a building, (a) is a state where a building does not fit in LCD, (b) is a state where the building is zoomed out and housed in LCD, (c) Is a state where a shift image is displayed. (A), (b) is a figure for demonstrating the calculation method for calculating the relationship between distortion amount and shift amount. It is a graph which shows the relationship between distortion amount and shift amount. It is a block diagram of an endoscope apparatus. It is a flowchart for producing | generating a shift image. (A), (b) is a figure for demonstrating the calculation method for calculating the relationship between distortion amount and shift amount.

  Hereinafter, a medical endoscope apparatus according to an embodiment of the present invention will be described with reference to the drawings. In addition, this invention is not limited by this embodiment.

  FIG. 1A is a schematic perspective view of an endoscope apparatus 201 according to the embodiment, and FIG. 1B is a schematic perspective view showing a distal end portion 219 of the endoscope apparatus 201 shown in FIG. FIG. 1C is a perspective view of the second lens group 5, and FIG. 2 is a schematic cross-sectional view showing the endoscope apparatus 201 according to the embodiment along the optical axes O and P. 2A shows an alignment position where the optical axis O of the first and second lens groups 3 and 5 and the optical axis P of the CCD 13 serving as an image sensor coincide with each other, and FIG. FIG. 3 is a schematic diagram schematically showing an LCD 15 that displays a building B. FIG. 3 shows a non-alignment position in which the optical axis P of the first and second lens groups 3 and 5 and the CCD 13 that is an image sensor are shifted. FIG. 3A shows a state where the building B does not fit in the LCD 15, and FIG. 3B shows a zoomed-out state where the building B fits in the LCD 15. State, FIG. 3 (c) is a state of displaying the shift image.

  4A and 4B are diagrams for explaining a calculation method for calculating the relationship between the distortion amount x and the shift amount S. FIG. 5 illustrates the distortion amount x and the shift amount S. FIG. 6 is a block diagram of the endoscope apparatus 201, and FIG. 7 is a flowchart for generating a shift image.

  An endoscope apparatus 201 according to the present embodiment includes an apparatus main body 205 and a scope unit 209 that is connected to the apparatus main body 205 and inserted into the body of a subject. The apparatus main body 205 and the scope unit 209 are connected via a wire 207. The scope unit 209 includes a scope operation unit 211 and an insertion unit 213. The insertion portion 213 includes an insertion support portion 215 and a bendable portion 217 that is continuous with one end portion of the insertion support portion 215. The scope operation unit 211 is connected to the bendable unit 215 by a wire (not shown), and the operator of the endoscope apparatus 201 operates the scope operation unit 211 so that the bendable unit 217 is vertically and horizontally with respect to the longitudinal direction. Can be bent.

  As shown in FIG. 1B, the distal end portion 219 of the bendable portion 217 has an objective lens 1, an illumination lens 221 for irradiating a subject from a light source (not shown), and an endoscope device 1. A forceps port 223 for an operator to insert and remove the treatment tool and a water supply port 225 for supplying a liquid for cleaning the objective lens 1 and the illumination lens 221 are arranged.

  Further, the optical system provided at the tip 219 will be described. This is an image pickup means for acquiring image information of a subject by incidence of light beams from the first and second lens groups 3 and 5 and the first and second lens groups 3 and 5 which are optical systems having an optical axis O. The alignment position (see FIG. 2A) where the CCD 13, the optical axis O of the first and second lens groups 3, 5 and the optical axis P of the CCD 13 coincide, and the first and second lens groups. The first and second lens groups 3 and 5 and the CCD 13 are connected between the optical axes O of 3 and 5 and the non-alignment position where the optical axis P of the CCD 13 does not coincide (see FIG. 2A). The actuator 17 that is a relatively movable drive means, the first image information acquired by the CCD 13 at the alignment position, and the second image acquired by the CCD 13 at the non-alignment position (see FIG. 2B). A distortion amount x (see FIG. 2A) acquired from the information; A calculation unit 115 (see FIG. 6), which is a calculation means for calculating the relationship between the optical axis O of the second lens group 3, 5 and the shift amount S of the optical axis P of the CCD 13 (see FIG. 2B). An image processing unit 109 that is an image processing unit that generates a shift image (see FIG. 3C) from the first or second image information based on the relationship between the distortion amount and the shift amount S. . Various drive mechanisms such as piezoelectric elements can be used as the drive means.

  In addition, the first and second lens groups 3 and 5 have an asymmetrical shape in plan view (that is, viewed in the direction of the optical axis O). FIG. 1C shows the second lens group 5 having an asymmetrical shape about the optical axis O. A plurality of recesses 5 a are provided on the outer peripheral surface of the second lens group 5. Each recess 5 a constitutes a hole for receiving the illumination lens 221 and a part of the forceps opening 223. In addition, carbon black, which is an antireflection material, is applied to the side surface 5b of the second lens group 5 in order to prevent the influence of reflected light. Similarly to the second lens group 5, the first lens group is also provided with a hole for receiving the illumination lens 221 and a concave portion having a shape complementary to the forceps opening 223, and is formed on the side surface of each lens of the first lens group 3. Also, carbon black is applied. Needless to say, the antireflection material can be any material as long as it is a material that can prevent reflection of light. Moreover, you may employ | adopt the structure which plants a felt material on the side surface of a lens as a light reflection preventing material.

  Furthermore, the objective lens 1, the first and second lens groups 3, 5, and the image sensor 13 are provided by a bellows-shaped covering member 281 so that the optical path of light passing through each element is maintained in a desired environment. Surrounded. That is, a closed optical path space is formed by the objective lens 1, the first and second lens groups 3 and 5, the image sensor 13, and the covering member 281. In addition, even if the imaging device 13 is a movable imaging device 13 as shown in FIG. 2A, the bellows-shaped covering member 281 is used so that the closed sealed space can be maintained as described above. . The covering member 281 is not limited to the bellows-like structure, and can be formed of various flexible materials such as a rubber O-ring so that the optical path space can be maintained in a closed space. Furthermore, it is preferable to fill the closed optical path space with an inert gas such as nitrogen or argon from the viewpoint of maintaining the optical path in a desired state.

  In the present embodiment, the light path incident on the objective lens 1 passes through the first and second lens groups 3 and 5 and reaches the image sensor 13, but the second optical path space is closed. The space such as a space for closing only the optical path between the lens group 5 and the image sensor 13 can be changed according to the use environment. The imaging device 13 of the present embodiment includes a plurality of pixels arranged in a rectangular shape and a circular base material on which the pixels are arranged, and a covering member 281 is attached to the base material. However, it goes without saying that the shape of the substrate and the covering member and the arrangement shape of the pixels can be appropriately changed.

  As shown in FIG. 1C, a lens function capable of acquiring a second shift image at a non-alignment position shifted by a distance S downward in the vertical direction perpendicular to the optical axis O (in FIG. 1C) as will be described later. The lens diameter of the lens group 5 is dimensioned so that For example, since the second lens group 5 has the concave portion 5a, the amount of deviation from the optical axis O cannot be set relatively large in the left-right direction and the vertical direction upward in FIG.

  As shown in FIG. 6, the apparatus main body 205 of the endoscope apparatus 201 has an LCD 15 that is a liquid crystal screen and a control unit 101 that converts signals from the CCD 13 into video signals as accompanying components (see FIG. 6). ), An operation unit 113 (see FIG. 6) through which an operator using the endoscope apparatus 201 inputs a command, an external memory 111 (see FIG. 6), and a light source unit that supplies light to the illumination lens 221. (Not shown). Further, as shown in FIG. 6, the control unit 101 includes a CPU (central processing unit) 103 that controls each component, a RAM (Random Access Memory) 105 that stores acquired image information, and the like. A ROM (Read Only Memory) 107 in which a program for operating the mirror device 201 is stored is provided. Each component of the endoscope apparatus 201 is electrically connected through a bus.

  Further, in the CPU 103, the optical axis P of the CCD 13 is shifted in the vertical direction (vertical direction when the endoscope apparatus 201 is placed on a horizontal plane) with respect to the optical axis O of the first and second lens groups 3 and 5. As described above, the actuator 17 that can move the CCD 13, the angular velocity sensor 51 for detecting camera shake of the endoscope device 201, and the CCD 13 are electrically connected to each other, and the CCD 13, the motor 17, the angular velocity sensor 51, and the CPU 103 are connected to each other. It is controlled by sending and receiving signals between them.

  The camera shake prevention function of the present embodiment measures the amount of shake (movement) of the endoscope apparatus 201 itself by the angular velocity sensor 51, and based on the amount of movement, the actuator 17 is a drive means that moves the CCD 13 in the vertical direction. Is driven, and the CCD 13 is moved up, down, left, and right so that light reaches a predetermined position. Of course, based on the amount of movement of the endoscope device 201 acquired by the angular velocity sensor 51, instead of moving the CCD 13, the optical system (for example, the second lens group 5) is moved by the driving means, and a predetermined position of the CCD 13 is moved. It is also possible to apply a method for causing light to reach and preventing camera shake.

  Next, the shift function by the endoscope apparatus 201 having the above configuration will be described. In the initial state, the optical axis O of the first and second lens groups 3 and 5 of the endoscope apparatus 201 and the optical axis P of the CCD 13 coincide with each other (see FIG. 2A). )It is in. An operator operates the shift function using the operation unit 113 of the endoscope apparatus 201.

  The photographer points the endoscope apparatus 201 toward the building B as a desired subject while watching the LCD 15 of the endoscope apparatus 201. In the present specification, the subject is described as a building B in order to facilitate understanding of the shift function. It is identified whether or not the subject is within the LCD 15, that is, the area in the CCD 13 (step S 101 in FIG. 7). At this time, for example, as shown in FIG. 3A, when the entire building does not fit within the area of the LCD 15, the optical system (on the wide-angle side of the zoom function mounted in the endoscope device 201 in advance) The first and second lens groups 3 and 5) are operated by the operation unit 113 and adjusted so that the entire building B is accommodated in the LCD 15 (step S102 in FIG. 7). At this time, as shown in FIG. 3B, the left and right wall surfaces of the building B are displayed on the LCD 15 in a tapered state. Further, the image information at this time is stored in storage means such as the RAM 105 and the external memory 111 as first imaging information at an alignment position where the optical axis O and the optical axis P coincide (see FIG. 1A). (Step S103 in FIG. 7).

  Next, the drive signal from CPU103 is sent to the actuator 17, and the actuator 17 act | operates. The actuator 13 moves the CCD 13 so that the optical axis P of the CCD 13 is arranged at a non-alignment position shifted by a distance S1 in the vertical direction perpendicular to the optical axis O (see FIG. 2B). The image information at this time is displayed on the LCD 15 in a state where the left and right wall surfaces of the building B extend parallel to each other (substantially in the vertical direction), as shown in FIG. The second image information is stored in the storage means such as the memory 111 (step S104 in FIG. 7).

  Next, the calculation unit 115 converts the first image information at the alignment position (see FIG. 3B) and the second image information at the non-alignment position (see FIG. 3C). Based on this, the relationship between the distortion amount x and the shift amount S is calculated.

  The distortion amount x and the shift amount S are calculated as follows. It is the ratio of the length (number of pixels) of the upper side 33 to the length (number of pixels) of the bottom 31 of the building B based on the first image information shown in FIG. 4 (a) corresponding to FIG. 3 (b). The distortion amount b0 / a0 is acquired. On the other hand, based on the second image information (shifted image) shown in FIG. 4B corresponding to FIG. 3C, the length (pixels) of the upper side 37 with respect to the length (number of pixels) of the base 35 of the building B The distortion amount b1 / a1 that is the ratio of the number) is acquired.

  Here, x is a distortion amount indicating the ratio of the length (number of pixels) of the upper side 33 to the length (number of pixels) of the bottom 31 of the building B, and S is the optical system (first and second lenses). The distance (shift amount) between the optical axis O of the groups 3 and 5) and the optical axis P of the CCD 13 is used. Then, the following expression 1 indicating the relationship between the distortion amount x and the shift amount S with respect to the upper side 33 is acquired (step S105 in FIG. 7). When Equation 1 is acquired, the photographer adjusts the shift amount S by the operation unit 113 while watching the LCD 15, adjusts the distortion amount x (that is, b / a) of the building B, and acquires an arbitrary shift image. it can.

  S = {1 / (b1 / a1-b0 / a0)}. {(S1-S0) x + (b1 / a1) .S0- (b0 / a0) .S1} (Formula 1)

  According to the above configuration, the distortion amount x is calculated from the first image information at the alignment position (T point in the graph in FIG. 5) and the second image information at the non-alignment position (point U in the graph in FIG. 5). The relationship of the shift amount S is calculated and acquired and stored in a storage means such as the RAM 105. In the above step S105, the relationship between the shift amount S related to the upper side 33 and the distortion amount x of the building B has been described. However, in this step, the width dimension of the building B is arranged below the pixel row constituting the upper side 33. Are also calculated and obtained for each of the pixel columns corresponding to. For example, it is assumed that the number of pixels that define the height dimension of the building B (height dimension) is h. In this case, there are h stages of pixel columns (including a pixel column that configures the upper side b) that define the length in the width direction (the horizontal direction in FIG. 3) that configures the building B. With respect to all the pixel columns in the h stage, a relational expression between the shift amount S of each pixel column and the distortion amount x of the building B is calculated and acquired.

  Thereafter, when the operator acquires a shift image having an arbitrary distortion amount (for example, the point V in the graph of FIG. 5, the distortion amount b2 / a2 and the shift amount S2), an expression related to the pixel column for h stages. Based on 1 and the first and second image information, the h-stage image information generated by the image processing unit 109 can be displayed and viewed on the LCD 15 (step S106 in FIG. 7).

  In the above embodiment, it is identified whether or not the entire building B, which is the subject, falls within the imaging area of the CCD 13 (step S101), and if not, adjustment is made so as to fit (step S102). Needless to say, these steps are not essential steps when generating a shift image. This embodiment merely shows an example of generating a shift image of the building B.

(Modification 1)
In the above-described embodiment, the CCD 13 serving as the image pickup device is moved by the actuator 17. However, the endoscope apparatus according to Modification 1 fixes the CCD 13 and the optical system (the first lens group 3 or the second lens group 3). The lens group 5) is moved. For example, it is possible to provide a shift function by moving the optical axis of the second lens group 5 serving as a correction optical system on a vertical line that is a perpendicular to the optical axis P of the CCD 13.

  In this configuration, the operator of the endoscope apparatus 201 uses the operation unit 113 to first match the optical axis O of the optical system (first and second lens groups 3 and 5) with the optical axis P of the CCD 13. First image information as shown in FIG. 3B is acquired at the alignment position (see FIG. 2A) and stored in storage means such as the RAM 105. Then, at a non-alignment position (see FIG. 2B) where the optical axis of the second lens group 5 is shifted in a direction perpendicular to the optical axis P of the CCD 13, a building B as shown in FIG. The second image information is acquired and stored in storage means such as the RAM 105. Thereafter, Equation 1 indicating the relationship between the distortion amount x and the shift amount S is acquired as in the above embodiment, and an arbitrary shift image is generated by the image processing unit 109 based on Equation 1 and displayed on the LCD 15.

  After that, as in the embodiment, while operating the operation unit 113, the shift image generated by the image processing unit 109 is displayed on the LCD 15, and the operation unit 113 is operated while watching the image, and the image of the desired building B is displayed. Information is acquired and stored in the external memory 111 or the like as necessary.

(Modification 2)
Modification 2 of the above-described embodiment is a configuration that realizes a shift function by using a camera shake function that is built in the endoscope apparatus 201 in advance. A camera shake image is a phenomenon in which a photographed image flows even though a still subject is imaged by an operator moving the endoscope device 201 while the shutter of the endoscope device is open. It is.

  In the camera shake prevention function, as described above, the movement (camera shake amount) of the endoscope apparatus 201 itself in the three-dimensional direction obtained by the angular velocity sensor 51 is detected, and the optical axis O of the optical system and the CCD 13 are detected according to the camera shake amount. The optical axis P is relatively moved.

  In the endoscope apparatus of the second modification, the operator substitutes the image information necessary for the shift function by the operation unit 113 with the image information acquired by the camera shake function. Specifically, the image information when the camera shake function is not activated is acquired as the first image information, the image information when the camera shake function is activated is acquired as the second image information. The shift amount information when the second image information is acquired is acquired. In the camera shake function, the calculation unit 115 calculates the shift amount of the CCD 13 based on the shake amount acquired by the angular velocity sensor 51.

  Note that the shift amount in the camera shake function is not necessarily the amount of movement in the direction perpendicular to the optical axis O. Therefore, when a shift image related to the vertical direction is acquired as in the embodiment, the vertical component of the shake amount, that is, the shift amount S is calculated based on the acquired shake amount, and the storage unit such as the RAM 105 is used. Stored in

  Further, similarly to the above-described embodiment, the distortion amount x, which is the ratio of the upper side b to the lower side a of the same building B, is calculated and stored in the storage means such as the RAM 105 in the same way as in the previous embodiment. Is done. Thereafter, the relational expression of Expression 1 is acquired from the first and second image information, the distortion amount x, and the shift amount S stored in the storage unit by the calculation unit. Therefore, the operator can acquire an arbitrary shift image while viewing the captured image generated by the image processing unit 109 and displayed on the LCD 15.

  As described above, the shift function can be realized by using the image information acquired by the built-in camera shake prevention function without newly incorporating a component for the shift function in the endoscope apparatus. Therefore, the shift function can be given to the endoscope apparatus with a simpler configuration than in the embodiment and the first modification.

  In the configuration of the second modification, the shift amount S acquired in connection with the camera shake prevention function and the distortion amount x between the upper side and the bottom side of the building B are relatively small because they originate from camera shake. That is, it is assumed that the image information or the like used for the shift function in the camera shake prevention function does not include image information when the distortion amount x is 1 (no distortion).

  Even in this case, as described in connection with the above-described embodiment, the image information of the shift image can be calculated and acquired. That is, the value of the graph T in FIG. 5 is obtained from the first image information acquired at the alignment position, and the value of the V point in the graph in FIG. 5 is obtained from the second image information acquired at the non-alignment position. If so, the relationship of Equation 1 is calculated and acquired for each pixel row of h stages recognized as the building B. For example, the CPU 103 receives a command for acquiring image information (a state in which there is no distortion with a distortion amount of 1) at the point U from the operation unit 113. At that time, the calculation unit 115 calculates and obtains the distortion amount x related to the pixel columns (width dimensions) for each of the h stages from Equation 1 regarding the pixel columns for the h stages, and obtains the shift image (in this case, the upper side and the bottom side). Are generated on the LCD 15.

  Thus, as long as the first image information at the alignment position and the second image information at the non-alignment position can be acquired, the relationship represented by Equation 1 can be calculated and acquired. Can be generated by the image processing unit 109 and the image information can be displayed on the LCD 15 (step S106 in FIG. 7). Also in the embodiment, similarly, even if the amount of distortion of the shift image indicated by the second image information is smaller than 1 (that is, there is distortion), an arbitrary shift image can be acquired from Expression 1. Needless to say, you can.

  Note that the shift function of the second modification is realized by a configuration in which an actuator used for a camera shake function is used to move the image sensor or the optical system with respect to the optical axis. By the way, the shift amount used in the shift image tends to be larger than the shift amount according to the vertical component (or horizontal component) of the blur amount. For example, in the graph of FIG. 5, it is expected that the maximum value of the shift amount used in the shift image is the U point and the maximum value of the shift amount corresponding to the blur amount is the V point. In order to increase the accuracy of the shift image generated under such conditions, the drive range in which the optical system or the image sensor can be moved by the actuator constituting the camera shake function is driven by the actuator according to the shift amount according to the blur amount. It is preferable to set wider than the range (for example, so that the shift amount can reach the V point).

  In the above embodiment and the first and second modifications, the shift function for acquiring the shift image in the vertical direction is provided. However, the present invention is not limited to this configuration. For example, it is possible to acquire a shift amount in the horizontal direction and generate a shift image. FIGS. 8A and 8B correspond to FIGS. 4A and 4B and are diagrams for explaining a calculation method for calculating the relationship between the distortion amount and the shift amount.

  Regarding the horizontal direction, the first image information (see FIG. 8A) at the alignment position where the optical axis of the optical system and the optical axis of the image sensor coincide with each other, and the second image information at the non-alignment position where both optical axes do not coincide. Image information (see FIG. 8B), the amount of distortion (a0 / b0, a1 / b1) in the horizontal direction and the amount of shift (distance between the optical axis O and the optical axis P in the horizontal direction). Get the relationship. This relational expression can be expressed by the same expression as Expression 1. The operator can generate a shift image having an arbitrary distortion amount. Furthermore, it goes without saying that the shift direction of the shift image is not limited to the vertical direction and the horizontal direction, and can be set in any direction.

  In the above-described embodiment and the first modification thereof, based on the two pieces of image information, Formula 1 indicating the relationship between the distortion amount and the shift amount is acquired, and a desired shift image is acquired from the relationship equation. The present invention is not limited to this configuration. That is, it goes without saying that a shifted image can be acquired without using the above-described relational expression within a range in which the imaging device or the correction optical system with respect to the optical axis O can be physically (mechanically) shifted. Therefore, a shift image can be acquired without using the above equation 1 within the movement range (that is, a shiftable range) of the image sensor or the correction optical system with respect to the optical axis O, and shift is performed in a region beyond the shiftable range. An image may be generated using Expression 1.

  Further, in Expression 1 of the present embodiment, the relationship between the distortion amount and the shift amount is represented by a straight line, but the relationship of the present invention is not limited to a straight line. Based on the type of subject, the composition of the subject, and the like, the shift amount is used to acquire the distortion amount and the shift amount, the information is accumulated, and an expression representing the relationship is derived from the accumulated information.

  In addition, in this embodiment and the modification 1, although the actuator 17 which is a drive means to move between an alignment position and a non-alignment position is provided, it is not an indispensable component requirement of this invention. That is, it is only necessary that the first image information at the alignment position and the second image information at the non-alignment position can be acquired for the same subject. For example, a first image sensor (or correction optical system) arranged at the alignment position and a second image sensor (or correction optical system) arranged at the non-alignment position are provided, and the former is applied to the same subject. First image information is acquired, and second image information is acquired from the latter. It is also possible to obtain a shift image by obtaining Equation 1 from these two pieces of image information. According to this configuration, since the actuator is not provided, the endoscope apparatus can be simplified. As described above, the endoscope apparatus may be configured to include a plurality of imaging elements (or correction optical systems).

  In the above-described embodiment and its modifications 1 and 2, the shift function is incorporated in the endoscope apparatus, but the present invention is not limited to this configuration. For example, it can be incorporated into a device that needs to be miniaturized, such as a compact digital camera, a mirrorless single-lens camera, a mobile phone with a camera, a print sealing machine, an automatic ID photograph camera, and a digital video camera.

  In the above-described embodiment and its modifications 1 and 2, each of the first and second lens groups 3 and 5 includes a predetermined number of lenses. However, the present invention is not limited to the above-described configuration. It goes without saying that the number of groups and the number of lenses constituting the lens group can be changed as appropriate. Furthermore, the first and second lens groups 3 and 5 are composed of a plurality of optical lenses for the purpose of correcting chromatic aberration. However, if a lens capable of correcting chromatic aberration is used, the first and second lens groups can be constituted by a single lens.

  In the above-described embodiment and its modifications 1 and 2, the relational expression between the distortion amount and the shift amount is acquired based on two pieces of image information. However, the relational expression between the distortion amount and the shift amount based on three or more pieces of image information. It is also possible to improve the generation accuracy of the shift image. Furthermore, it goes without saying that the subject for which the shift image is created is not limited to the building of the above-described embodiment, and can be applied to any subject having distortion such as a human body or a structure.

201 Endoscopic device 3, 5 First and second lens group 13 CCD
15 LCD
17 Actuator 51 Angular velocity sensor 101 Control unit 103 CPU
105 RAM
109 Image processing unit 113 Operation unit 115 Calculation unit B Building S Shift amount x Distortion amount

Claims (4)

An optical lens,
An image sensor disposed on the optical axis of the optical lens;
Driving means for relatively moving the optical lens and the image sensor so that the optical axis of the image sensor deviates from the optical axis of the optical lens;
An endoscope apparatus , wherein an optical path space closed by a bellows member is formed between the optical lens and the imaging element, and the optical lens and the imaging element are supported by the bellows member . The light beam from the optical lens is incident on the image sensor, and image information of a subject is acquired by the image sensor,
The first distortion amount acquired from the first image information by the image sensor at the alignment position where the optical axis of the optical lens and the optical axis of the image sensor coincide with each other, and the optical axis of the optical lens and the image sensor. The relationship between the second distortion amount acquired from the second image information by the image sensor at the non-alignment position where the optical axis does not match, and the shift amount of the optical axis of the optical lens and the optical axis of the image sensor. Computing means for computing;
The endoscope apparatus according to claim 1, further comprising: an image processing unit that generates a shift image based on a relationship between the first and second distortion amounts and the shift amount .   The endoscope apparatus according to claim 1, wherein a side surface of the optical lens is covered with a light reflection preventing material for preventing light reflection.   The endoscope apparatus according to any one of claims 1 to 3, wherein the optical lens has an asymmetrical shape with respect to an optical axis thereof.

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