JP5210719B2 - Electronic endoscope and image processing program - Google Patents

Description

  The present invention relates to an electronic endoscope and an image processing program that acquire video information along the axial direction and the circumferential direction of a transparent cylindrical body from the inside of the transparent cylindrical body.

  Many electronic endoscopes, for example, as described in Patent Document 1 below, insert a thin insertion part into a hole or body cavity, and use an objective lens attached to the distal end of the insertion part as an affected part in the insertion direction. To get video information.

  In the prior art described in Patent Document 2 below, an omnidirectional light receiving unit is provided at the distal end of the insertion portion, and an image over the entire circumference in the circumferential direction at the distal end of the insertion portion is reflected on the convex mirror in the omnidirectional light receiving unit, thereby taking an image I try to do it.

Japanese Patent Application Laid-Open No. 09-192084 JP 2003-279862 A

  The solid-state image sensor housed in the endoscope distal end portion has a smaller area and a smaller number of pixels than a solid-state image sensor used in a digital camera or the like. Therefore, when a detailed image of an affected area or the like is to be taken, the video information obtained by one shot is limited to an image with a narrow visual field range.

  For this reason, in order to obtain a wide range of video information, the operator of the endoscope takes a picture while manually adjusting the insertion position of the endoscope. That is, attention must be paid to both searching for an affected area, that is, adjusting the insertion position and photographing.

  In the case of an endoscope that captures an image of the entire circumference of the insertion section using an omnidirectional light receiving unit, image information of the entire circumference of the inserted insertion position can be obtained at one time. Is condensed on the light receiving surface of one solid-state imaging device, the obtained video information is compressed video information, and a detailed image of a small affected part cannot be obtained.

  An object of the present invention is to provide an electronic endoscope and an image processing program having a novel structure capable of accurately acquiring a wide range of detailed video information.

  An electronic endoscope according to the present invention includes a cylindrical transparent body in which at least a cylindrical observation window is transparent, a main body having a cylindrical portion connected to the cylindrical portion of the cylindrical transparent body, and the cylindrical shape A rotating body that rotates around the central axis of the cylindrical transparent body and moves in the direction of the central axis inside the transparent body and the main body, and the cylindrical portion of the cylindrical transparent body provided on the rotating body An objective mirror that reflects light incident through an objective lens provided at a position facing the main body in the direction of the main body, the objective lens that converts the incident light into a parallel light flux and travels to the objective mirror, and the main body An image sensor that receives light reflected by the objective mirror and converts it into an electrical signal, and a driving means that is provided inside the main body and rotates the rotating body and drives it in the central axis direction. Imaging of the image sensor Characterized in that it comprises a magnification correcting means for correcting the image size after the image processing into a predetermined size when the image processing captures No..

  The rotating body of the electronic endoscope according to the present invention includes a disk-shaped member on which the objective lens is mounted and the objective mirror is mounted, and a cylindrical shape integrally provided on the body side of the disk-shaped member. And a member.

  The electronic endoscope according to the present invention includes a female screw threaded on the inner peripheral surface of the main body and a male screw threaded on the outer peripheral surface of the cylindrical member and screwed into the female screw. And a male screw that moves the cylindrical member in the direction of the central axis when the cylindrical member is rotationally driven by the means.

  The objective lens of the electronic endoscope according to the present invention is characterized in that an optical axis is provided in a direction perpendicular to a rotation axis of the rotating body.

  The objective mirror of the electronic endoscope according to the present invention is characterized in that light incident through the objective lens is reflected in the direction of the main body along an optical path passing through the central axis.

  The electronic endoscope according to the present invention includes a half mirror provided in the middle of an optical path of light reflected by the objective mirror, light emitted from the illumination light, reflected by the half mirror, and reflected by the objective mirror. And a light emitter that illuminates a subject through the objective lens.

  The electronic endoscope according to the present invention includes an image memory for storing captured image data corrected by the magnification correction unit.

  The magnification correction unit of the electronic endoscope according to the present invention is characterized in that the correction is performed using a magnification value measured corresponding to a driving amount by the driving unit.

  The image processing program of the present invention includes a cylindrical transparent body in which at least the observation window of the cylindrical portion is transparent, a main body having a cylindrical portion connected to the cylindrical portion of the cylindrical transparent body, and the cylindrical transparent A rotating body that rotates about the central axis of the cylindrical transparent body and moves in the direction of the central axis inside the body and the main body, and the cylindrical portion of the cylindrical transparent body that is provided on the rotating body. An objective mirror that reflects light incident through an objective lens provided at a facing position in the direction of the main body, the object lens that converts the incident light into a parallel light flux and travels to the objective mirror, and the main body An image sensor that receives light reflected by the objective mirror and converts it into an electrical signal, and a driving means that is provided inside the main body and rotates the rotating body and drives it in the central axis direction. With electronic An image processing program for image processing of captured image data captured by a endoscope, comprising: a step of correcting a magnification of an image size after image processing to a predetermined size when capturing an image signal of the image sensor and performing image processing It is characterized by.

  The magnification correction of the image processing program according to the present invention is performed using a magnification value measured in correspondence with a driving amount by the driving unit and stored in a memory of the electronic endoscope.

  According to the present invention, it is possible to acquire a high-accuracy image over a wide range of the cylindrical inner peripheral surface.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is an external perspective view of an electronic endoscope according to an embodiment of the present invention. The electronic endoscope of the present embodiment can be referred to as a side view type, and is a rigid type. The electronic endoscope 1 includes a main body portion 2 and a transparent capsule portion 3 that are outer shells, a moving lens frame portion 4 housed inside, and an imaging drive unit portion 5 (see FIG. 2) described later. Composed.

  FIG. 2 is an exploded perspective view of the electronic endoscope 1, and FIG. 3 is a longitudinal sectional view of the electronic endoscope 1.

  The main body 2 is formed of a resin material or the like in a cylindrical shape with a bottom, and a cylindrical battery storage portion 2b is provided on the bottom (lower side in FIG. 2) 2a. The storage portion 2b is hermetically closed by the battery lid 12.

  Further, in the illustrated example, two rigid gripping tubes 13 and 14 made of resin are projected and fixed to the outside on the bottom portion 2a, and by operating the gripping tubes 13 and 14, The entire endoscope 1 can be inserted into and pulled out from a hole or a body cavity as a subject. In some cases, the electronic endoscope 1 is used by inserting wiring into the gripping tubes 13 and 14.

  A precise female screw 2c centering on the axis of the main body 2 is engraved on the inner peripheral surface of the main body 2. A member (moving lens frame) 4 on which the male screw is formed is screwed and rotated. As a result, the member 4 advances and retracts in the axial direction.

  The transparent capsule portion 3 is a cylindrical body formed of a hard transparent resin, one end side (tip side) is formed in a hemispherical shape, an opening end portion 3b opposite to the hemispherical portion 3a, and the main body portion 2 The opening end 2d is aligned and fixed by bonding. In the illustrated example, the entire capsule portion 3 is formed of a transparent resin, but at least a portion that becomes an observation window of the cylindrical portion 3c may be transparent, and the hemispherical portion 3a may be opaque. The observation window is a portion where an objective lens 17 described later faces as the moving lens frame rotates and moves. The hemispherical portion 3a and the cylindrical portion 3c may be formed separately from each other without being integrally formed of the same material, and may be integrally joined. In addition, the transparent resin should just be transparent with respect to the light of specific wavelengths, such as infrared light, for example, and does not necessarily need to be transparent with respect to visible light.

  The hemispherical portion 3a may be formed to have a smaller diameter than illustrated, and the tip of the cylindrical body 3c of the transparent capsule portion 3 may be smoothly connected to the hemispherical portion 3a after being narrowed to a tapered shape. If it does in this way, it will become easy to guide and insert the tip part of transparent capsule part 3 also in a small hole and a body cavity. In the case of the present embodiment, since the outer diameter of the cylindrical portion 3c of the transparent capsule portion 3 and the outer diameter of the main body portion 2 are exactly the same, no step is generated between them.

  The moving lens frame portion 4 includes an objective lens mounting portion 4a in which a resin material is formed in a disc shape, and a cylindrical member 4b having substantially the same diameter as the objective lens mounting portion 4a. The objective lens mounting portion 4a is bonded and fixed so as to be integrated with the opening end of the endoscope 1 at the opening end, and the opening end is closed. The outer diameter of the objective lens mounting portion 4a is formed to be slightly smaller than the inner diameter of the transparent capsule portion 3, so that the objective lens mounting portion 4a can be moved smoothly in the transparent capsule portion 3 without rattling.

  On the outer peripheral surface of the cylindrical member 4b, a precise male screw 4c that is screwed into the female screw 2c engraved on the inner peripheral surface of the main body 2 is engraved over the entire axial length of the cylindrical member 4b. An internal gear 4d is formed on the inner peripheral surface of the cylindrical member 4b. The internal gear 4d is formed by teeth that are parallel to the axis and that extend over the entire axial length of the cylindrical member 4b at equal intervals in the circumferential direction.

  A cylindrical hole 4e having a bottom in the upper end direction (the distal direction of the electronic endoscope 1) is drilled in the central axis portion of the objective lens mounting portion 4a, and the objective mirror 16 is accommodated in the cylindrical hole 4e. ing. The objective mirror 16 has a shape obtained by cutting a cylindrical glass body at an angle of 45 degrees, and a plane reflection film is formed on the cut surface at an angle of 45 degrees.

  The objective lens mounting portion 4a has an imaging hole 4f for imaging that extends straight in the radial direction of the disk-shaped member, and one end of the imaging hole 4f is opened on the outer peripheral side surface of the objective lens mounting portion 4a. An objective lens 17 made of a concave lens is provided. The other end of the imaging hole 4f is opened in the cylindrical hole 4e, and the subject light that has entered the hole 4f through the objective lens 17 travels as a parallel light flux, and is reflected by the above-described oblique 45 ° reflecting surface of the objective mirror 16. The light beam travels along the central axis of the cylindrical member 4b with a parallel light beam.

  In FIG. 3, in order to clearly show the parallel light beam in the imaging hole 4f, the tooth of the internal gear 4d that is visible on the other side of the parallel light beam is not shown, and the parallel light beam is indicated by a white portion. ing.

  The imaging drive unit 5 is fixedly installed inside the main body 2 using a stay member (not shown) with a peripheral wall portion of the battery housing 2b provided on the bottom 2a of the main body 2 as a support. The imaging drive unit 5 includes three substrates 21, 22, and 23 in the illustrated example.

  A control unit 25 including a driver circuit of a stepping motor and the like is provided on the lowermost substrate (bottom 2a side) substrate 21, an image memory 26 for storing captured image data is provided on the intermediate substrate 22, and an upper substrate 23. Are provided with a solid-state imaging device 27 such as a CCD type image sensor or a CMOS type image sensor and a stepping motor 28.

  A lens holder 29 formed in a cylindrical shape is provided at the center of the substrate 23, and a solid-state image sensor 27 is accommodated therein. A condensing lens 30 is installed at the upper end opening of the lens holder 29, and the parallel light beam (subject light) incident along the central axis is incident on the light receiving surface of the solid-state image sensor 27 by the condensing lens 30. Imaged.

  A half mirror 31 placed at an angle of 45 degrees obliquely with respect to the optical axis of the parallel light beam (= the central axis of the cylindrical member 4b) in the portion immediately before the light collecting lens 30 of the parallel light beam incident on the light collecting lens 30. Is provided. And the illumination lens 32 which condenses illumination light so that it may become a parallel light beam with respect to the half mirror 31, and LED33 which light-emits illumination light is provided. The half mirror 31, the illumination lens 32, and the LED 33 are fixed to the substrate 23.

  A stepping motor 28 is fixed to the periphery of the substrate 23, and a motor gear (spur gear) 36 is attached to the rotating shaft of the stepping motor 28. The rotation axis of the stepping motor 28 is provided in parallel with the central axis of the cylindrical member 4b (= the optical axis of the parallel light beam), and a spur idle gear 37 is engaged with the motor gear 36.

  The rotation shaft of the idle gear 37 is pivotally supported perpendicularly to the substrate 23, and the number of teeth of the idle gear 37 is larger than the number of teeth of the motor gear 36. For this reason, the rotational speed of the stepping motor 28 is decelerated and transmitted to the idle gear 37. The idle gear 37 is meshed with an internal gear 4d provided on the inner peripheral surface of the cylindrical member 4b.

  When the stepping motor 28 rotates, the idle gear 37 rotates, and the cylindrical member 4b rotates accordingly. When the cylindrical member 4b rotates, the cylindrical member 4b of the movable lens frame portion 4 is screwed into or out of the main body portion 2 depending on the rotation direction, and advances and retreats in the axial direction.

  The electronic endoscope 1 is provided with a power switch (not shown). When the power switch is turned on, power from the power battery 11 is supplied to each component of the imaging drive unit 5 through a wiring (not shown). The imaging operation and driving operation are performed as described later.

  For example, the power switch may be provided on the bottom 2a of the main body 2 so that the manual operation switch is turned on and off. Alternatively, a switch terminal that responds to a magnetic force may be built in the main body unit 2, and the switch terminal may be turned on / off by moving the magnet closer to or away from the outside of the electronic endoscope 1.

  FIG. 4 is a functional block diagram of the imaging drive unit 5. The CPU 41 that performs overall control of the entire system stores a control program and also operates as a work memory, the image memory 26 provided on the board 22 described in FIG. 3, and an LED drive circuit that drives the LED 33 43, an image sensor driver 44 for driving the image sensor 27, and a pulse generator 46 for supplying a drive pulse to a motor driver 45 for driving the stepping motor 28 are connected.

  When the power switch 47 is turned on, power is supplied from the power battery 11 to each part to start the operation, and the motor 28 is rotationally driven. Thereby, the moving lens frame part 4 rotates inside the electronic endoscope 1 and advances and retreats in the axial direction. Also, the emitted light from the LED 33 is condensed into parallel light by the illumination lens 32, the parallel light is reflected by the half mirror 32 toward the objective mirror 16, and the parallel light reflected by the objective mirror 16 passes through the objective lens 17 to the subject. Irradiated in the direction to become illumination light.

  The reflected light from the subject is taken into the electronic endoscope 1 through the objective lens 17, and the light image of the subject reflected by the objective mirror 16 proceeds to the condenser lens 30 as a parallel light flux, and is picked up by this condenser lens 30. An image is formed on the light receiving surface of the element 27.

  An imaging signal of a subject imaged by the imaging element 27 is captured by the CPU 41 and subjected to image processing, and stored in the image memory 26 as, for example, JPEG image data.

  FIG. 5 is a flowchart showing the processing procedure of the control program stored in the control memory 42. When the power switch 47 is turned on, this control program is started, and first, the stepping motor 28 is driven to the origin side (step S1). The origin side is, for example, the state shown in FIG. 3, that is, the direction in which the position of the objective lens 17 is the front end side of the electronic endoscope 1.

  In the present embodiment, in order to reduce the cost, a sensor for detecting whether or not the stepping motor 28 has reached the origin is not provided. Therefore, in the next step S2, whether or not the timer for counting a predetermined time has been counted up. If the predetermined time has not elapsed, step S1 is repeatedly executed. If a sensor for detecting that the origin has been reached is provided, step S1 may be repeated until the origin of this sensor is detected.

  The predetermined time may be the longest time required for the stepping motor 28 to reach the origin. For example, the state shown in FIG. 7 shows a state in which the moving lens frame unit 4 is rotated and moved to the lowest position. From this state, the moving lens frame unit 4 is rotated by the rotation of the stepping motor 28. The time required to reach the origin position shown in FIG.

  Thereby, the movable lens frame 4 is in any intermediate position between the state of FIG. 3 and the state of FIG. 7 (the state where the lower end of the cylindrical member 4b is in contact with the bottom 2a of the main body 2a). Even in such a case, the objective lens 17 is always at the origin position if the stepping motor 28 is driven in the origin position direction for a predetermined time.

  When the timer counts the predetermined time, the process proceeds from step S2 to step S3, and the contents of the counter described later are cleared to zero. Then, the process proceeds to step S4, and imaging processing is performed.

  In the imaging process, the LED 33 is turned on to irradiate illumination light from the objective lens 17, the light reflected from the subject is taken into the electronic endoscope 1 from the objective lens 17, and incident on the light receiving surface of the imaging device 27 from the subject. The light is imaged, and the CPU 41 drives the image sensor 27 via the image sensor driver 44, captures the imaging signal of the subject obtained from the image sensor 27 from the image sensor 27, processes the image, and stores it in the image memory 26. The process until it is done.

  In the next step S5, the stepping motor 28 is driven by the specified number of pulses. In the next step S6, the specified number of pulses is added to the count value of the counter. In the next step S7, the total count value of the counter is set to the specified number. Compare.

  If the total count value of the counter has not reached the designated number, the process returns from step S7 to step S4 to perform the imaging process, and thereafter the processing loop of steps S4 to S7 is repeatedly executed. When the total count value of the counter reaches the designated number, the processing in FIG. 5 is terminated.

  FIG. 8 is a diagram showing how the imaging field of view of the objective lens 17 moves when step S4 of FIG. 5 is repeatedly executed. In the first imaging process performed at the origin position, the subject image in the field of view indicated by “No. 001” in FIG.

  After the subject image of the field of view “No. 001” is captured, the stepping motor 28 with the specified number of pulses is driven in step S5, so that the cylindrical member 4b rotates by the specified number of pulses. As a result, the cylindrical member 4b is screwed into the main body 2 and retracted, and the next field of view is “No. 002” in FIG. 8. It is stored in the memory 26.

  Thereafter, the field of view is No. 003 → No. 004 → No. 005... To repeat the imaging process and storage of image data in the memory 26. FIG. 6 shows a state in which the movable lens frame portion 4 is half-turned inside the transparent capsule 3 as compared with the state of FIG. The imaging field of view when the moving lens frame part 4 has completed one round (one rotation) from the origin position in the transparent capsule part 3 is No. 1 in FIG. No. 011 and the imaging field of view when two rounds (two rotations) have been completed is No. 1 in FIG. 021.

  FIG. 7 shows a state in which the lower end of the cylindrical member 4b is in contact with the bottom 2a of the main body 2 and cannot move further in that direction. When the state shown in FIG. ) Is completed. That is, the “specified number” used in step S7 in FIG. 5 is the total number of pulses from the origin position to the state in FIG.

  The moving example of the imaging visual field illustrated in FIG. 8 is the number of designated pulses in step S5 of FIG. 5 so that the left and right end portions of adjacent imaging visual fields are in contact with each other in the rotation direction of the moving lens frame 4 serving as a rotating body. Shows the case where is set. The pitch of the threads provided on the inner peripheral surface of the main body 2 and the outer peripheral surface of the cylindrical member 4b is such that the upper and lower ends of the imaging fields adjacent to each other in the rotation axis direction are in contact with each rotation. The case where it is designed is shown.

  In the moving example of the imaging field of view illustrated in FIG. 8, the state of the entire field of view of the inner peripheral surface of the cylindrical subject to be observed can be captured without omission and acquired as image data. However, in this embodiment, in order to further improve the accuracy of the captured image data, the number of pulses of the stepping motor is set so that adjacent imaging fields of view overlap each other, and the pitch of the spirals 2c and 4c is designed. ing.

  FIG. 9A shows the overlapping state of the imaging fields at the same rotational position. In the illustrated example, the designated number of pulses of the stepping motor 28 is such that the next imaging field n + 1 in the rotation direction with respect to a certain imaging field n overlaps at least half (1/2 pitch) the rotation direction length of the imaging field. (Step S5 in FIG. 5) is set.

  FIG. 9B shows an overlapping state of the imaging field of view in the axial direction at the same rotation angle position. In the example shown in the figure, the inside of the main body 2 is arranged so that the next imaging field m adjacent in the axial direction to a certain imaging field n overlaps at least half (1/2 pitch) of the axial length of the imaging field. The pitch of each thread of the female screw 2c provided on the peripheral surface and the male screw 4c provided on the outer peripheral surface of the cylindrical member 4b is designed.

  By doing this, it is possible to acquire a plurality of images (four images in the example of FIG. 9) of the same affected part position, and improve the reliability of the imaging data.

  FIG. 10 is a flowchart illustrating a correction process performed on captured image data. This correction process is performed, for example, during the imaging process in step S4 of FIG.

  When captured image data (for example, JPEG image data of a subject image) is generated in step S41, magnification correction processing is next performed on the JPEG image data (step S42), and then rotation correction processing is performed on the JPEG image data. After the application (step S43), the corrected JPEG image data is stored in the image memory 26 (step S44).

  The magnification correction process in step S42 is the following process. With the objective lens 17 shown in FIG. 3, incident light from the subject is converted into a parallel light flux and enters the objective mirror 16, and is reflected by the objective mirror 16 as the parallel light flux and reaches the condenser lens 30.

  The distance between the objective mirror 16 and the condenser lens 30 changes from the longest distance state of FIG. 3 to the shortest distance state of FIG. However, since it is a parallel light beam, a light image having a certain size is incident on the light receiving surface of the image sensor 27 regardless of the change in the distance.

  However, in order to obtain a perfect parallel light beam, a high-performance objective lens 17 is required, which increases the manufacturing cost of the electronic endoscope 1. When the low-cost objective lens 17 is used, for example, as shown in FIG. 11, the parallel light beam 51 reflected by the objective mirror 16 is not a perfect parallel light beam, but slightly spreads in the illustrated example. Of course, it may become narrower.

  When the condensing lens 30 of the image sensor 27 moves back and forth in the axial direction and is at the position A in FIG. 11, a light image having a length a on one side is formed on the light receiving surface of the image sensor 27. When the light beam comes to, an optical image having a side length b (> a) is formed.

  For example, in the case of separately observing the captured images in the individual imaging fields shown in FIG. 8 (also in FIG. 9), the size of the acquired image at the position A and the acquired image at the position B in FIG. No problem. However, when the subject images for each imaging field of view in FIG. 8 are pasted together so as to form a single image, if the individual captured images have different sizes, they cannot be pasted together. End up.

  Therefore, in this embodiment, every time imaging processing is performed, the image data is multiplied by an appropriate magnification, and the size of the image obtained for each imaging field of view is set to a predetermined size (for example, the size of the image data at the origin position). And are stored in the image memory 26.

  Each magnification value to be used is measured in advance before shipment of the product (electronic endoscope 1), and is stored as a product-specific value in a predetermined area of the control memory 42 so as not to be rewritten. This magnification value is obtained as a value corresponding to the axial distance from the origin position (this distance can be obtained as a value corresponding to the cumulative value of the number of drive pulses from the origin position of the stepping motor 28). .

  FIG. 12 is a flowchart showing a processing procedure for obtaining the magnification measurement value. When measurement is started, first, in step S51, the stepping motor 28 is moved to the origin position. Next, imaging is performed (step S52), the size of the image data is measured (step S53), and the magnification (in this example, the magnification is “1” because it is an image at the origin position) is stored in the control memory. (Step S54).

  Next, the stepping motor 28 is driven to move to the center position (the center position between the origin position (position in FIG. 3) and the end position (position in FIG. 7)) (step S55), and the image is taken (step S56). The data size is measured (step S57), the magnification value is calculated and stored in the control memory 42 (step S58).

  Next, the stepping motor 28 is driven to move to the end position (step S59), imaging (step S60), image data size measurement (step S61), magnification value calculation and storage in the control memory 42 (step S62). ) To finish this process.

  In this example, the magnification values of the three points of the start position (origin position), the center position, and the end point position are stored in the memory 42, and the CPU 41 obtains and uses individual magnifications at intermediate positions from the data of these three points by interpolation calculation. However, it is also possible to adopt a configuration in which the data is measured more finely and stored in the memory 42.

  The rotation correction process in step S43 in FIG. 10 is the following process. Now, as shown in FIG. 13A, it is assumed that a continuous arrow image 55 having the same helix as the spirals of the threads 2c and 4c is being imaged as the imaging field of view moves.

  At the origin position shown in FIG. 8 (the same applies to FIG. 9 but will be described with reference to FIG. 8), the relationship between the captured image data in the imaging field of view and the light receiving surface of the solid-state imaging device 27 is as shown in FIG. The relationship shown in That is, the outer rectangular frame in FIG. 13B shows the light receiving surface 52, and the inner small rectangular frame is the imaging field No. 1. A rectangular frame 001 (hereinafter referred to as an imaging visual field 53) is shown. The image shown in FIG. 13B is an erect image.

  The imaging element 27 is fixedly installed on the main body 2 and is immovable with respect to the main body 2. On the other hand, when the movable lens frame portion 4 rotates, the objective mirror 16 also rotates, so that the imaging visual field reflected on the objective mirror 16 also rotates, and the imaging visual field 53 reflected on the light receiving surface 52 also rotates.

  FIG. 13C shows the relationship between the light receiving surface 52 and the imaging field 53 when the moving lens frame portion 4 makes 1/8 round. Since it is 1/8 round, the imaging visual field 53 rotates with respect to the light receiving surface 52 by 360 degrees / 8 = 45 degrees. Therefore, the image obtained in the state shown in FIG. 13C is an image rotated by 45 degrees with respect to the erect image obtained in the state shown in FIG. 13B. Therefore, unless the image obtained in the state shown in FIG. 13C is reversely rotated by −45 degrees, the arrow image 55 does not become a continuous image when the image is pasted to an erect image.

  Similarly, every time the moving lens frame 4 rotates, the image rotates. FIGS. 13D, 13E, and 13F are views showing the relationship with the imaging field 53 of the light receiving surface 52 when 2/8, 3/8, and 4/8, respectively. And as shown in FIG.13 (g), when the moving lens frame part 4 makes one round, an erect image will be obtained again.

  As described above, a captured image obtained at a position other than the rotation angle position at which an erect image is obtained must be corrected in the reverse direction by the amount corresponding to the rotation angle. A single image cannot be obtained by pasting together. For this reason, rotation correction processing is performed in step S43, and all captured images are converted into erect images, and then stored in the image memory 26.

  The rotation angle information used in the rotation correction process performed for each imaging field of view can be obtained from the cumulative value of the number of drive pulses of the stepping motor 28 from the origin position. However, the product information varies depending on the gear ratio and the number of teeth of the internal gear 4d and the idle gear 37 of the product (electronic endoscope 1), the number of designated pulses in step S5 in FIG. Eigenvalue information is stored in a predetermined area of the control memory 42 in a non-rewritable manner, and the rotation angle is calculated using this information to perform rotation correction processing.

  Note that the image processing in steps S42 and S43 in FIG. 10 is preferably performed in parallel with the driving of the designated number of pulses in step S5 in FIG.

  After the imaging by the electronic endoscope 1 is completed, the accumulated data in the image memory 26 in FIG. 4 is read out to the outside. This reading may be performed using radio, or may be performed using wiring inserted into the gripping tubes 13 and 14 shown in FIG. Alternatively, the image memory 26 may be provided so as to be removable from the electronic endoscope 1, and the extracted image memory 26 may be read by a separate personal computer.

  FIG. 14 is a functional block diagram according to another embodiment of the imaging drive unit 5 of FIG. The only difference from the embodiment of FIG. 4 is that the captured image data is sent to an external monitor so that the captured image can be observed on-line on the external monitor and an operation instruction can be input from the outside.

  In the case of this embodiment, the CPU 41 may send the image signal acquired from the image sensor 27 to an external video processor as it is without performing image processing, and display the subject image image-processed by the video processor on an external monitor. good.

  In the image processing in steps S42 and S43 in FIG. 10, unless a high-performance arithmetic processing unit (CPU 41) is used, the imaging field of view cannot be moved one after another, and continuous imaging cannot be performed. It will be interrupted.

  For this reason, the process of steps S42 and S43 in FIG. 10 is skipped and the process proceeds from step S41 to step S44, and the image data obtained for each imaging field of view (the above-mentioned JPEG image data) is stored in the image memory 26 as it is. It is also possible to transfer the image data to an external high-performance video processor so that the video processor performs the image processing in steps S42 and S43. The external video processor can easily perform the magnification correction and the rotation correction process as long as the product-specific information stored in the predetermined area of the control memory 42 is acquired.

  Communication between the external video processor or external monitor and the CPU 41 may be wired or wireless. In the case of performing wired communication, an external power source can be used by inserting a power line in the wiring.

  In addition to the control program of FIG. 5, a control program for moving the visual field position of the objective lens 17 to an arbitrary imaging visual field position of FIG. 8 in accordance with an external operation instruction may be installed as the control program. .

  In the above-described embodiment, the moving lens frame 4 is rotationally driven by the stepping motor 28. However, a motor that can accurately control the rotation angle and the rotation length may be used instead of the stepping motor. Needless to say.

Next, a preferred use example of the electronic endoscope 1 according to the above-described embodiment will be described.
(I) Example of use as a uterine endoscope:
In recent years, cervical cancer affecting women is becoming younger, but early detection is important because cervical cancer is not important by partial extraction if it is detected early. However, women tend to resist seeing their bodies and the screening population does not increase.

  The electronic endoscope 1 according to the above-described embodiment is effective for screening for cervical cancer if the size and shape are designed to an appropriate size. The electronic endoscope 1 shown in FIG. 1 is inserted into a woman's vaginal cavity, and the electronic endoscope 1 is inserted into the uterus from the distal end (hemisphere 3a) so that a series of imaging visual field positions shown in FIG. 8 reach the cervix. By inserting into the cervix, it is possible to image the state of the inner peripheral surface of the cervix without omission.

  For example, if the electronic endoscope 1 is inserted into the cervix by the patient's own hand in the examination room and the doctor instructs the insertion position or monitors the captured image online in a separate room, the examination is performed. It is possible to increase the population.

  Further, in the electronic endoscope 1 described above, when the power switch 47 is turned on, the position of the objective lens 17 automatically returns to the origin position and the imaging process is automatically performed as described with reference to FIG. The electronic endoscope 1 can be lent to a patient, and the patient himself / herself can take an image of his / her cervix at home. The doctor can make a diagnosis by collecting the electronic endoscope 1 and examining the captured image data in the image memory 26.

(Ii) Examples of use as colonos and rectal endoscopes:

Conventionally, when examining the large intestine or the rectum, there is a problem that the affected part can be observed only from an obliquely upward direction because it is observed with an endoscope having an image sensor mounted on the tip. However, if the electronic endoscope 1 of the above-described embodiment is inserted to the affected part position and imaging is performed, the affected part can be observed from the vertically upper position, and can be observed in more detail and can be diagnosed with high accuracy. It becomes.

(Iii) Example of use as an industrial endoscope:
For example, the electronic endoscope 1 of the above-described embodiment can be used as an industrial endoscope that observes fine scratches in a thin pipe. An endoscope 1 having a dimension and shape corresponding to the size of the hole to be observed and the opening of the gap and the insertion depth is prepared. As described above, since it is possible to observe scratches and the like from the vertically upper side with respect to the inner peripheral surface of the hole, more detailed observation is possible. In addition, once inserted, it is possible to observe a wide range (a whole range in the axially movable length of the moving lens frame portion 4), and the oversight rate of small scratches is also reduced.

  The electronic endoscope according to the present invention can capture a wide range of images in detail, and can also observe an affected area or a wound from vertically above. It is useful as a medical endoscope and an industrial endoscope.

1 is an overall external perspective view of an electronic endoscope according to an embodiment of the present invention. It is a disassembled perspective view of the electronic endoscope shown in FIG. It is a longitudinal cross-sectional view of the electronic endoscope shown in FIG. It is a functional block diagram of the control unit mounted in the electronic endoscope shown in FIG. It is a flowchart which shows the process sequence of the control program which CPU shown in FIG. 4 performs. It is a longitudinal cross-sectional view which shows the state which the moving lens frame part made | formed half way from the state shown in FIG. It is a longitudinal cross-sectional view which shows the state which the movable lens frame part shown in FIG. 6 moved down to the imaging completion position. It is a figure which shows the mode of a movement of the imaging visual field of the objective lens shown in FIG. It is a figure which shows a mode that an imaging visual field is moved for every half pitch to a rotation direction (a) and an axial direction (b). It is a flowchart which shows the image processing procedure of the imaged image data. It is explanatory drawing of the magnification correction process shown in FIG. It is a flowchart which shows the measurement procedure of the magnification value used by the magnification correction process shown in FIG. It is explanatory drawing of the rotation correction process shown in FIG. FIG. 5 is a functional block diagram of a control unit according to an embodiment instead of FIG. 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electronic endoscope 2 Main-body part 2a Bottom part 2b Battery accommodating part 2c Female screw 3 provided in the inner peripheral surface Transparent capsule part 3a Hemispherical part 3c at the tip Cylindrical part 4 Moving lens frame part (rotating body)
4a Disc-shaped objective lens mounting portion 4b Cylindrical member 4c Male screw 4d provided on the outer peripheral surface 4d Internal gear 4f Imaging hole 5 Imaging drive unit 11 Power supply battery 12 Battery lid 13, 14 Grasping tube 16 Objective mirror 17 Objective lens 21 , 22, 23 Substrate 26 Image memory 27 Solid-state imaging device 28 Stepping motor 29 Lens holder 30 Condensing lens 31 Half mirror 32 Illumination lens 33 LED (light emitting body)
36 Motor gear 37 Idle gear 41 Control device (CPU)
47 Power switch

Claims (10)

  A cylindrical transparent body in which at least the observation window of the cylindrical portion is transparent; a main body portion having a cylindrical portion connected to the cylindrical portion of the cylindrical transparent body; and the inside of the cylindrical transparent body and the main body portion. A rotating body that rotates about the central axis of the cylindrical transparent body and moves in the direction of the central axis, and an objective that is provided on the rotating body and that faces the cylindrical portion of the cylindrical transparent body An objective mirror that reflects light incident through the lens in the direction of the main body, the objective lens that converts the incident light into a parallel luminous flux and travels to the objective mirror, and is fixedly installed on the main body and reflected by the objective mirror An image sensor that receives the received light and converts it into an electrical signal, a drive unit that is provided inside the main body and drives the rotary body to rotate and drives in the direction of the central axis, and captures an image signal of the image sensor In image processing An electronic endoscope, characterized in that it comprises a magnification correcting means for correcting the image size after the image processing into a predetermined size when.   The rotating body includes a disk-shaped member on which the objective lens is mounted and the objective mirror is mounted, and a cylindrical member that is integrally connected to the main body side of the disk-shaped member. The electronic endoscope according to claim 1.   A female screw threaded on the inner peripheral surface of the main body and a male screw threaded on the outer peripheral surface of the cylindrical member and screwed into the female screw, and the cylindrical member is rotationally driven by the driving means. The electronic endoscope according to claim 2, further comprising a male screw that moves the cylindrical member in the direction of the central axis when being performed.   The electronic endoscope according to any one of claims 1 to 3, wherein an optical axis of the objective lens is provided in a direction perpendicular to a rotation axis of the rotating body.   5. The electronic endoscope according to claim 1, wherein the objective mirror reflects light incident through the objective lens in the direction of the main body along an optical path passing through the central axis. 6. .   A half mirror provided in the middle of the optical path of the light reflected by the objective mirror, and illuminating the subject through the objective lens by emitting illumination light, reflecting the illumination light by the half mirror, and reflecting by the objective mirror The electronic endoscope according to claim 1, further comprising a light emitter.   7. The electronic endoscope according to claim 1, further comprising an image memory for storing captured image data corrected by the magnification correction unit. The electronic endoscope according to claim 1, wherein the magnification correction unit performs the correction using a magnification value measured corresponding to a driving amount by the driving unit.   A cylindrical transparent body in which at least the observation window of the cylindrical portion is transparent; a main body portion having a cylindrical portion connected to the cylindrical portion of the cylindrical transparent body; and the inside of the cylindrical transparent body and the main body portion. A rotating body that rotates about the central axis of the cylindrical transparent body and moves in the direction of the central axis, and an objective that is provided on the rotating body and that faces the cylindrical portion of the cylindrical transparent body An objective mirror that reflects light incident through the lens in the direction of the main body, the objective lens that converts the incident light into a parallel luminous flux and travels to the objective mirror, and is fixedly installed on the main body and reflected by the objective mirror The image is picked up by an electronic endoscope that includes an imaging element that receives the received light and converts it into an electrical signal, and a driving means that is provided inside the main body and drives the rotating body to rotate and drive in the direction of the central axis. Captured image data The An image processing program for image processing, image processing program characterized by comprising the step of magnification correcting an image size after the image processing into a predetermined size when the image processing takes in imaging signals of the imaging element.   10. The image processing program according to claim 9, wherein the magnification correction is performed using a magnification value measured in correspondence with a driving amount by the driving unit and stored in a memory of the electronic endoscope.

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