Controller, endoscope system, control method, and control program

Abstract

A controller controls an image that is captured by an image sensor of an endoscope and is displayed on the display screen of a display device. The controller includes a processor. The processor acquires a first image that is an image captured by the image sensor, detects a first angle of a surgical instrument, and generates a second image rotated with respect to the first image on the basis of the first angle and a predetermined target angle. The first angle is an angle formed by the surgical instrument in the first image with respect to a predetermined reference line that is set with respect to a plane of the first image. A second angle formed by the surgical instrument in the second image with respect to the predetermined reference line is equal to the predetermined target angle.

1 . A controller configured to control an image that is captured by an image sensor of an endoscope and is displayed on a display screen of a display device,
 the controller comprising a processor,   wherein the processor acquires a first image that is an image captured by the image sensor,   the processor detects a first angle of a surgical instrument, the first angle being an angle formed by the surgical instrument in the first image with respect to a predetermined reference line that is set with respect to a plane of the first image, and   the processor generates a second image rotated with respect to the first image on a basis of the first angle and a predetermined target angle, the surgical instrument forming a second angle in the second image with respect to the predetermined reference line such that the second angle is equal to the predetermined target angle.   
     
     
         2 . The controller according to  claim 1 , wherein the processor generates the second image by rotating the image sensor. 
     
     
         3 . The controller according to  claim 1 , wherein the processor generates the second image by rotating the first image through image processing. 
     
     
         4 . The controller according to  claim 1 , wherein the target angle is 0°. 
     
     
         5 . The controller according to  claim 1 , wherein the processor rotates the first image about a rotation axis parallel to an optical axis of the endoscope. 
     
     
         6 . The controller according to  claim 5 , wherein the rotation axis passes through a center point of the first image. 
     
     
         7 . The controller according to  claim 1 , wherein the first angle is an angle formed by a longitudinal axis of a shaft of the surgical instrument in the first image with respect to the reference line, and
 the second angle is an angle formed by the longitudinal axis of the shaft of the surgical instrument in the second image with respect to the reference line.   
     
     
         8 . The controller according to  claim 1 , wherein the reference line is a straight line that forms a predetermined angle with respect to a horizontal line in the first image and is fixed relative to the first image. 
     
     
         9 . The controller according to  claim 1 , wherein the reference line is a horizontal line that is set in the first image and corresponds to a horizontal line on the display screen. 
     
     
         10 . The controller according to  claim 1 , wherein the reference line is a vertical line that is set in the first image and corresponds to a vertical line on the display screen. 
     
     
         11 . The controller according to  claim 1 , wherein the processor generates the second image when an absolute value of a difference between the first angle and the target angle is larger than a threshold value. 
     
     
         12 . The controller according to  claim 1 , further comprising a user interface that receives an input of a trigger from a user,
 wherein the processor acquires a third image in response to reception of a first trigger by the user interface, the third image being an image captured by the image sensor, and   the processor sets the target angle at a third angle of the surgical instrument in the third image, the third angle being an angle formed by the surgical instrument in the third image with respect to the reference line.   
     
     
         13 . The controller according to  claim 12 , wherein after the target angle is set, the processor acquires the first image in response to reception of a second trigger by the user interface. 
     
     
         14 . The controller according to  claim 1 , wherein the processor sets an angle of the surgical instrument at the target angle, the surgical instrument having a tip disposed on a predetermined horizontal line on the display screen. 
     
     
         15 . The controller according to  claim 1 , wherein the processor is operable in a rotation mode, and
 in the rotation mode, the processor regularly acquires the first image, detects the first angle, and generates the second image.   
     
     
         16 . The controller according to  claim 15 , further comprising a user interface that receives an input of turn-on/turn-off of the rotation mode. 
     
     
         17 . The controller according to  claim 16 , further comprising a storage unit that stores the predetermined target angle of an anatomical characteristic for each type of the anatomical characteristic,
 wherein when the user interface receives the input of the turn-off of the rotation mode,   the processor recognizes the type of the anatomical characteristic in the first image, and   the processor generates a fourth image rotated with respect to the first image on a basis of the predetermined target angle of the recognized type, the predetermined target angle being stored in the storage unit.   
     
     
         18 . An endoscope system comprising:
 an endoscope;   a moving device that comprises a robot arm and that moves the endoscope in a subject; and   the controller according to  claim 1 .   
     
     
         19 . A control method for controlling an image that is captured by an image sensor of an endoscope and is displayed on a display screen of a display device,
 the control method comprising:   acquiring a first image that is an image captured by the image sensor;   detecting a first angle of a surgical instrument, the first angle being an angle formed by the surgical instrument in the first image with respect to a predetermined reference line that is set with respect to a plane of the first image; and   generating a second image rotated with respect to the first image on a basis of the first angle and a predetermined target angle, the surgical instrument forming a second angle in the second image with respect to the predetermined reference line such that the second angle is equal to the predetermined target angle.   
     
     
         20 . A non-transitory computer-readable medium having a control program stored therein, the program being for controlling an image that is captured by an image sensor of an endoscope and is displayed on a display screen of a display device, the program causing a processor to execute functions of:
 acquiring a first image that is an image captured by the image sensor;   detecting a first angle of a surgical instrument, the first angle being an angle formed by the surgical instrument in the first image with respect to a predetermined reference line that is set with respect to a plane of the first image; and   generating a second image rotated with respect to the first image on a basis of the first angle and a predetermined target angle, the surgical instrument forming a second angle in the second image with respect to the predetermined reference line such that the second angle is equal to the predetermined target angle.