Abstract:
An electronic endoscope of the present invention includes a video-scope having an image sensor, a video-processor, to which a proximal end of the video-scope and a monitor are respectively connected, a character and mark generation controller, and an area-image changer. The character and mark generation controller generates character signals and indicator-mark signals, and then feeds the character signals and the indicator-mark signals to the monitor. The image-area changer changes a size of an image-area of the object image displayed on the screen of the monitor to another size, thus the object image is selectively displayed within one of plural image-areas on the screen in accordance with a size change of the image-area. The characters and mark generation controller includes a display-position adjuster that determines display-positions of the character information and the indicator-mark on the basis of a reference table, in which a correspondence relationship between each of the image-area and each of the display-positions of the character information and the indicator-mark is indicated.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to an electronic endoscope for displaying a body-cavity image on a TV monitor, the endoscope having a video-scope having an image sensor and a video-processor. In particular, this invention relates to an adjustment of display-positions of character information including a patient&#39;s name, displayed on the monitor with the body-cavity image. 
     2. Description of the Related Art 
     In an electronic endoscope, a video-scope includes an optical light guide extended therethrough, which is formed as a bundle of optical fibers. A video-processor includes a light source, such as a halogen lamp. When the video-scope is connected to the video-processor, a proximal end of the optical light guide is optically connected to the light source. Thus, an object to be photographed is illuminated by light radiating from a distal end of the optical light guide, and then an object image is formed on a CCD (Charge-Coupled-Device) provided at the distal end of the video-scope, which is an image sensor. The object image, formed on the CCD, is converted into analog image-pixel signals by photoelectric conversion. The analog image-pixel signals are fed to the video-processor and are suitably processed, so that video signals are generated. The video signals are then output to a TV monitor. Thus, a body-cavity image (for example, an image of a stomach) is displayed on the monitor. 
     Further, a CRT controller for generating character signals is incorporated in the video-processor. Thus, character information, such as a patient&#39;s name and a doctor&#39;s name, and a pointer for pointing to a specific portion of the cavity can be also displayed on the monitor with the body-cavity image. 
     As is well known, the CCD in the video-scope has a smaller size than that of a CCD used in a normal camera. Namely, a number of image pixels, included in one frame, obtained from the video-scope CCD, is less than a number of image pixels, included in one frame, obtained from the normal camera CCD. Therefore, the object image, formed on the CCD in the video-scope, is only displayed on a partial area of the screen of the monitor. Accordingly, in a conventional electronic endoscope, a size of the image-area, within which the object image is displayed, is selectively and optionally changeable when a detailed examination of the diseased portion in the organ is needed. Thus, the object image, displayed on the screen, is enlarged to a predetermined size. Also, a large-sized image-area can be returned to the original-sized image-area. 
     In accordance with the size-change of the image-area, the character information is also shifted. Namely, a display-position of each item of the character information is changed such that the character information does not overlap the image-area on the screen. A display-position of the pointer is changed only when the pointer is displayed beyond the image-area by the size-change of the image-area. 
     A control process for changing the displayed-positions of the character information and the pointer is performed under a program in the video-processor. In a source code of the program, which is made by using a programming language, such as the “C” programming language, a description for computing the display-positions corresponding to each item of the character information and the original-sized/the large-sized image-area is needed. 
     However, the size of the image-area, within which the object image is displayed on the screen, differs from one video-scope to another because of differing characteristics of the CCDs in the video-scopes. Further, a hospital name, a patient&#39;s registration number and a patient&#39;s sex, and etc., should be also displayed on the screen with the patient&#39;s name and age. Therefore, the description for determining the display-positions in the source code increases as the kinds of video-scopes and the amount of character information increases. As a consequence, the structure of the source code becomes complicated, and processing for displaying of the character information cannot be rapidly performed. 
     Then, as inspection of the source code is difficult, reliability of operation of the electronic endoscope as a whole decreases. Further, the capacity of a memory, in which the program is stored, cannot be reduced. 
     SUMMARY OF THE INVENTION 
     Therefore, an object of the present invention is to provide an electronic endoscope that can execute a processing for displaying the character information and the pointer in accordance with a size-change of the image-area by a simple program. 
     An electronic endoscope of the present invention has a video-scope having an image sensor, a video-processor, to which a proximal end of the video-scope and a monitor are respectively connected, a character and mark generation controller, and an image-area changer. 
     In the video-scope, an object image is formed on the image sensor provided at a distal end of the video-scope, and then image-pixel signals corresponding to the object image are generated. In the video-processor, image-pixel signals are processed and video signals are generated to display the object image on the monitor. The character and mark generation controller generates character signals and indicator-mark signals, and then feeds the character signals and the indicator-mark signals to the monitor at a timing, such that character information and an indicator-mark are respectively displayed at a position on a screen of the monitor with said object image. The image-area changer changes a size of an image-area of the object image displayed on the screen of the monitor to another size, thus the object image is selectively displayed within one of plural image-areas on the screen in accordance with a size-change of the image-area. 
     Further, the character and mark generation controller includes a display-position adjuster. The display-position adjuster determines display-positions of the character information and the indicator-mark on the basis of a reference table, in which correspondence between each of the image-areas and each of the display-positions of the character information and the indicator-mark is indicated. Thus, the character information and the indicator-mark are respectively displayed at the determined display-positions in accordance with the size-change of the image-area. 
     As the display-positions of the character information and the indicator-mark are determined on the basis of the reference table, the structure of the program is simple. Therefore, the reliability of the operation of the electronic endoscope improves, and further, the program can be stored in a reduced-capacity memory. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be better understood from the description of the preferred embodiment of the invention set forth below together with the accompanying drawings, in which: 
     FIG. 1 is a block diagram showing an electronic endoscope of an embodiment of the present invention. 
     FIG. 2 is a view showing images displayed on a screen of a monitor. 
     FIG. 3 is a view showing a keyboard. 
     FIG. 4 is a view showing a reference table. 
     FIG. 5 is a view showing a main routine regarding operations of the electronic endoscope as a whole. 
     FIG. 6 is a view showing an interrupt routine regarding an operation of the keyboard. 
     FIG. 7 is a view showing a subroutine of Step  102  in FIG.  5 . 
     FIG. 8 is a view showing a subroutine of Step  103  in FIG.  5 . 
     FIG. 9 is a view showing in detail the interrupt routine shown in FIG.  6 . 
     FIG. 10 is a view showing a subroutine of Step  403  in FIG.  9 . 
     FIG. 11 is a view of a subroutine of Steps  405  and  409  in FIG.  9 . 
     FIG. 12 is a view showing a subroutine of Step  604  in FIG.  11 . 
     FIG. 13 is a view showing a subroutine of Step  407  in FIG.  9 . 
     FIG. 14 is a view showing a subroutine of Steps  413  and  426  in FIG.  9 . 
     FIG. 15 is a view showing a sub routine of Steps  411  and  426  in FIG. 9, and further Step  103  in FIG.  5 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, the preferred embodiment of the present invention is described with reference to the attached drawings. 
     FIG. 1 is a block diagram of an electronic endoscope of the embodiment. This endoscope is used when an operation, an inspection or a treatment regarding an organ, such as a stomach, is performed. 
     The electronic endoscope includes a video-processor  20  and a video-scope  10 . The video-scope  10  is a flexible conduit, and is detachably connected to the video-processor  20 . A monitor  49  is also connected to the video-processor  20 . During an operation, a proximal end  18  of the video-scope  10  is connected to the video-processor  20 , and a distal end of the video-scope  10  is inserted into the body-cavity. When the video-scope  10  is connected to the video-processor  20 , data associated with a type of video-scope  10  is read from an EEPROM (Electronic Erasable Programmable ROM)  19  and then fed to a CPU (Central Processing Unit)  30 . The electronic endoscope is controlled by the CPU  30 . 
     The video-scope  10  includes a light guide  14  extended therethrough, formed as a bundle of optical fibers. When the proximal end  18  of the video-scope  10  is connected to the video-processor  20 , an incidence end  14   a  of the light guide  14  is optically connected to a lamp  22 , such as a halogen lamp, controlled by a lamp driver circuit  23 . Thus, light emitted from the lamp  22 , is directed to the incidence end  14   a  of the light guide  14  via a condenser lens  24 , and then radiates from the distal end of the light guide  14  toward an object S via a diffusion lens  15 . 
     A stop (diaphragm)  25  is provided between the lamp  22  and the incidence end  14   a  of the light guide  14 , and is driven by a stepping motor (not shown), which rotates by a driving-signal output from a driver circuit  28 . The stop  25  is used for adjusting a quantity of light directed from the lamp  22  to the incidence end  14   a  of the light guide  14 . Namely, the stop  25  is used for adjusting a quantity of the illuminating-light radiating from the distal end of the light guide  14 . 
     A CCD (Charge-Coupled-Device)  13 , which is an image sensor, is provided at the distal end of the video-scope  10 . When an object S is illuminated by the illuminating-light, light reflected from the object S is focused on the CCD  13  via an optical lens  12 , so that the object image is formed on the CCD  13 . 
     Photoelectric conversion devices (not shown) are provided on the CCD  13 , and red (R), green (G), and blue (B) color mosaic-filter elements are provided in front of the photoelectric conversion devices. Namely, in this embodiment, one chip color method is applied. The object image, formed on the CCD  13 , is converted into electrical image-pixel signals corresponding to predetermined colors by the photoelectric conversion devices. These analog image-pixel signals, corresponding to a frame, are successively read from the CCD  13  to an image-processing circuit  21  via a connector  16 , i.e., the object image is scanned. In this embodiment, a NTSC color method is applied as a color-television video-standard. Therefore, one frame worth of the analog image-pixel signals is scanned at regular time-intervals of {fraction (1/30)} sec. However, other color-television methods may be used in alternative embodiments. 
     In the image-processing circuit  21 , one frame worth of the analog image-pixel signals, output from the CCD  13  in order, is separated into analog image-pixel signals corresponding to the red R, analog image-pixel signals corresponding to green G, and analog image-pixel signals corresponding to blue B, respectively. Then, the analog image-pixel signals, corresponding to each color (R, G, B), are amplified and converted into digital image-pixel signals, respectively. Further, the digital image-pixel signals are subjected to various image-processes, such as a reset noise removal and gamma-correction, etc. One frame of luminance signals are successively generated on the basis of the digital image-pixel signals, and then fed to the CPU  30 . The stop  25  is controlled by the CPU  30  on the basis of the luminance signals. 
     The digital image-pixel signals are converted into analog image-pixel signals again in the image-processing circuit  21 , and are further converted into the video signals, in short, NTSC signals. The video signals are output from the image-processing circuit  21  to the monitor  49 . 
     Character-code is fed from the CPU  30  to a CRTC (Cathode Ray Tube Controller)  32  to display character information, such as patient&#39;s name, age etc, on the monitor  49 . In the CRTC  32 , character signals corresponding to the character information displayed on the monitor  49  are generated, and the character signals are output from the CRTC  32 . Similar to the character information, pointer signals corresponding to a pointer, which is an indicator-mark for pointing to a specific portion in the object image displayed on the monitor  49  (for example, a diseased portion), is generated in the CRTC  32 . 
     The character signals and the pointer signals are superimposed on the video signal output from the image-processing circuit  21 , and then the video signal including the character signals and the pointer signals is fed to the monitor  49 . One frame worth of the video signals are successively output to the monitor  49  at regular time-intervals of {fraction (1/30)} sec, thus the object image is displayed on the monitor  49 , as a moving picture. 
     Timing-control signals corresponding to an output-timing of the character and pointer signals output from the CRTC  32  are fed from the CPU  30  to the CRTC  32 , thus the character information and the pointer are displayed at a predetermined position on the monitor  49 , respectively. A timing generator (not shown), for synchronizing the image-pixel signals read from the CCD  13 , the video signals output from the image-processing circuit  21  and the character and pointer signals output from the CRTC  32 , is provided in the video-processor  20 . Thus, clock pulse signals are fed from the timing generator to the CCD  13 , the image-processing circuit  21  and the CRTC  32  by a clock frequency. 
     A panel switch  27  includes an up-switch  27 A, a down-switch  27 B and an auto/manual switch  27 C. When the up-switch  27 A and/or the down-switch  27 B are operated by an operator to set a level of brightness of the object image displayed on the monitor  49 , operation-signals are input to the CPU  30 , and thus the brightness of the object image is adjusted. The auto/manual switch  27 C is operated by an operator for selecting a method of an adjustment of the brightness. 
     When a keyboard  26  is operated, an operation-signal, regarding the object image and the character information and so on, is input to the CPU  30 . In this embodiment, an image-area, which is a displaying-area of the object image displayed on the monitor  49 , can be enlarged by operating the keyboard  26 . In this case, magnifying video signals, corresponding to an enlarged object image on the monitor  49 , are obtained by an interpolation processing, which is well known, in the image-processing circuit  21 , and are then fed to the monitor  49 . 
     When the object image on the monitor  49  is enlarged, the character and pointer signals are output from the CRTC  32  by a timing corresponding to the enlarged object image, thus the character information and the pointer are displayed at a position corresponding to the enlarged object image, respectively. 
     In the CPU  30 , a ROM  33  which is a nonvolatile memory  33 , a RAM  34  which is a volatile memory, and a RTC (Real Time Clock)  31  are provided. In the ROM  33 , a reference table, representing display-positions of the character information and the pointer, is stored as data. In the RAM  34 , a part of the display-positions of the character information and the pointer, which is read from the reference table, is temporarily stored. Then, the display-positions of the character information and the pointer on the monitor  49  are determined on the basis of the display-positions stored in the ROM  33  and the RAM  34 . Further, a list of patients who have been examined using the electronic endoscope is also stored in the RAM  34  as data. A current time and date are read from the RTC  31 , and the character-code corresponding to the current date and time is fed to the CRTC  32 . Thus, the time and date are displayed on the monitor  49 . 
     FIGS. 2 to  4  are views of display-positions of the character information and the pointer. FIG. 2 is a view showing pictures displayed on a screen of the monitor  49 . FIG. 3 is a view showing the keyboard  26 . FIG. 4 is a view showing the reference table. 
     In this embodiment, two kinds video-scopes, type A of the video-scope  10  and a type B of the video-scope  10  can be connected to the video-processor  20 . Further, regarding the image-area of the object image on the screen, a normal-display or a magnification-display can be selected by operating a F 8  (function  8 ) key  52  on the keyboard  26  (See FIG.  3 ). The image-area of the object image on the screen is changed by operating the F 8  key  52 . 
     A picture P 1 , shown in FIG. 2, indicates a picture displayed on the screen W of the monitor  49  in a case where the type A of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display. The body-cavity image is displayed within a normal image-area IA. Then, the character information, namely, a patient&#39;s name CH 1 , an ID number (patient&#39;s registration number) CH 2 , a patient&#39;s age CH 3 , a patient&#39;s sex CH 4 , a doctor&#39;s name CH 5 , a scope-name CH 6 , which is a code-name of the video-scope  10  connected to the video-processor  20 , a date CH 7  and a time CH 8  are respectively displayed at a position on the screen W with the object image. Further, the pointer P pointing to a diseased-portion Q is displayed in the normal image-area IA. The pointer P is displayed and erased by operating a F 4  (function  4 ) key  53  (See FIG.  3 ), as described below. A shifting of the pointer P on the screen W is performed by operating an up-shift key  50 U, a down-shift key  50 D, a right-shift key  50 R, and a left-shift key  50 L, shown in FIG.  3 . During an operation, the display-state is usually set to normal-display. A size of the normal image-area IA depends on a number of the pixels of the CCD  13  in the type A of the video-scope  10 . 
     When a character key  54  on the keyboard  26  (See FIG. 3) is operated, a letter corresponding to a position, at which a cursor C is displayed (herein, “D” in the doctor&#39;s name CH 5 ), is replaced to other letter corresponding to the operated character key, as described later. Then, the position of cursor C is shifted to rightward by one letter worth (herein, “r” in the doctor&#39;s name CH 5 ). The shifting of the position of the pointer P and the cursor C is performed by operating an Enter key  51 , the up-shift key  50 U, the down-shift key  50 D, the right-shift key  50 R, and the left-shift key  50 L (See FIG.  3 ). 
     When the F 8  key  52  is depressed by the operator in a case where the object image is displayed within the normal image-area IA, the display-state is changed to magnification-display, shown in the picture P 1 ′ in FIG. 2, as described later. Thus, the size of the normal image-area IA is enlarged to a large-sized magnifying image-area IA′, within which the object image is displayed. The magnifying image-area IA′ is located at a center portion of the screen W. 
     In accordance with the size-change of the image-area, character information is displayed at corner portions of the screen W. A position of each item of character information is shifted beyond the magnifying image-area IA′ on the screen W, such that the character information overlaps the object image within the magnifying image-area IA′ as little as possible. On the other hand, the display-position of the pointer P is not changed when the display-position of the pointer P is within the magnifying image-area IA′. 
     Inversely, when the F 8  key  52  is depressed by the operator in a case where the object image is displayed within the magnifying image-area IA′, the display-state is returned to the normal-display. Therefore, the magnifying image-area IA′ is again changed to the normal-image-area IA, and the display-positions of the character information are shifted to the original display-positions, respectively. On the other hand, the position of the pointer P is not changed when the display-position of the pointer P is within the normal image-area IA. 
     However, when the position of the pointer P is beyond the normal image-area IA or the magnifying image-area IA′ in a case where the size-change of the image-area is performed, the position of the pointer P is shifted within the normal image-area IA or the magnifying image-area IA′, as described later. 
     When the type B of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, the object image is displayed within a normal image-area IB, as shown in picture P 2  on the screen W in FIG.  2 . Note that, as shown in FIG. 2, the normal image-area IB is different from the normal image-area IA because of the difference between the CCD  13  in the type A of the video-scope  10  and the CCD  13  in the type B of the video-scope  10 . 
     Similarly to the type A of the video-scope  10 , when the F 8  key  52  is depressed by the operator in a case where the object image is displayed within the normal image-area IB, the display-state is changed to the magnification-display, as shown in a picture P 2 ′ in FIG.  2 . Thus, the size of the normal image-area IB is enlarged to a large-sized magnifying image-area IB′, within which the object image is displayed. In accordance with the size-change of the image-area, the character information is displayed at corner portions of the screen W. similarly to the type A of the video-scope  10 . When the F 8  key  52  is depressed by the operator in a case where the object image is displayed within the magnifying image-area IB′, the display-state is returned to normal-display. 
     The reference table T, shown in FIG. 4, represents x-y coordinates of each item of the character information and the pointer P. As shown in FIG. 2, a x-y coordinate system is defined with respect to the screen W of the monitor  49 , and an origin of the x-y coordinate system is positioned at the upper left-most corner of the screen W. Note that, values of x-coordinates ascend from a left-position to right-position. On the other hand, values of y-coordinates ascend from an upper-position to a lower-position. 
     In the reference table T, the character information is arranged by item (the patient&#39;s name CH 1 , the patient&#39;s age CH 2 , . . . , the time CH 8 ), and x-y coordinates (x,y) of 8 items are respectively represented. In this embodiment, x-y coordinates, corresponding to four image-areas, are prepared for each item. Namely, x-y coordinates (x,y) corresponding to the type A of the video-scope  10  and the normal-display, x-y coordinates (x,y) corresponding to the type A of the video-scope  10  and the magnification-display, x-y coordinates (x,y) corresponding to the type B of the video-scope  10  and the normal-display, and x-y coordinates (x,y) corresponding to the type B of the video-scope  10  and the magnification-display are represented in the reference table T. Note that, the x-y coordinates (x,y) indicate a position of a head letter in each item. For example, when the type A of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, the x-y coordinates of the patient&#39;s name CH 1  is “(1,1)”, which is a position of a letter “P”, as shown in FIG.  2 . 
     The reference table T is stored in the ROM  33  (shown in FIG. 1) as data in advance. Namely, x-y coordinates-data is stored in addresses of the ROM  33 . Herein, the x-y coordinates (x,y) are represented by using a 10-columns 8-rows array h as given by following formula: 
     
       
         (x,y)=(h[cp,vs], h[cp,vs])  (1) 
       
     
     Note that, an item variable cp corresponds to the items. For example, the patient&#39;s age CH 3  corresponds to the item variable cp of “3”. On the other hand, a display-position variable vs corresponds to a x-coordinate or a y-coordinate corresponding to the four image-areas. For example, when the type B of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, the display-position variable vs of the x-coordinate is “3”, and the display-position variable vs of the y-coordinate is “4”. 
     The array h is utilized in the source code (programming language), and corresponds to the address in the ROM  33 . Namely, the x-y coordinates (x,y) are stored in the array h in the source code. When the type B of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, the x-y coordinates (x,y) of the doctor&#39;s name CHS is: 
     
       
         (x,y)=(h(5,5),h(5,6))=(24,13)  (2) 
       
     
     Further, in this embodiment, when the type of the video-scope  10  and the display-state are determined, as described later, corresponding x-y coordinates-data is read from the ROM  33  and then temporarily stored in the RAM  34  (shown in FIG.  1 ). Herein, the x-y coordinates (x,y) stored in the RAM  34  are represented by using a 10-columns 2-rows array H, corresponding to addresses in the RAM  34 , as follows: 
     
       
         (x,y)=(H[cp,1], H[cp,2])  (3) 
       
     
     For example, when the type B of the video-scope  10  is connected to the video-processor  20  and the display-state is the magnification-display, the x-y coordinates (x,y) of the item variable cp of “5” (doctor&#39;s name CHS) are: 
     
       
         (x,y)=(H[5,1],H[5,2])=(0,28)  (4) 
       
     
     Note that, the array H[cp,1] indicates the x-coordinate of the item corresponding to the item variable cp, and the array H[cp,2] indicates the y-coordinate of the item corresponding to the item variable cp. 
     While the display-state is not changed or the exchange of the video-scope  10  is not performed, the character information is displayed on the screen in accordance with the x-y coordinates stored in the array H. When the display-state is changed or the exchange of the video-scope  10  is performed, as described later, corresponding x-y coordinates-data is read from the array h and stored in the array H. Thus, the x-y coordinates (x,y) in the array H are rewritten. Then, the character information is displayed on the basis of the x-y coordinates (x,y) newly stored in the array H. 
     In the reference table T, a minimum limitation-position of the pointer A min  corresponding to the item variable “ 9 ” and a maximum limitation-position of the pointer A max . corresponding to the item variable “10” are also represented. As shown in FIGS. 2 and 4, x-y coordinates (x,y) of the minimum and maximum limitation-position of the pointer A min  and A max  indicate corner-positions of one of the image-areas IA, IA′, IB, IB′. Note that, the x-y coordinates (x,y) of the minimum and maximum limitation-position of the pointer A min  and A max  respectively represent a head position of the pointer of an arrow. 
     As mentioned above, the pointer P should be displayed within the image-area of the object image. Therefore, when the display-state is changed or the exchange of the video-scope  10  is performed, the display-position of the pointer P is determined depending upon the maximum limitation-position of the pointer A max  and the minimum limitation-position of the pointer A min , such that the display-position of the pointer P is not beyond the image-area of the object image. In this embodiment, the pointer P is shifted to a boundary of the image-area when the display-position of the pointer P is beyond the image-area by the size-change of the image-area, as described later. The x-y coordinates (x,y) regarding above the display-positions of the pointer P is also stored in the array h and further the array H. 
     In this way, the display-positions of the character information and the pointer P are determined depending upon the reference table T. 
     Note that, as shown in FIG. 2, when the display-state is magnification-display, a number of letters, which can be displayed in each column on the screen W, of the type A of the video-scope  10  is different from that of the type B of the video-scope  10  (See Pictures P 1 ′ and P 2 ′) Here, the number of letters of the type A of the video-scope  10  is “42”, while, the number of letters of the type B of the video-scope  10  is “35”. This difference is because the number of pixels of the CCD  13  provided in the type A of the video-scope  10  is different from that of the CCD  13  provided in the type B of the video-scope  10 , as is conventionally well known. Namely, The clock frequency, output from the timing generator (not shown in FIG. 1) to the CCD  13 , differs in accordance with the number of the pixels of the CCD  13 , i.e., the type of the video-scope  10  when the display-state is the magnification-display. Therefore, for example, as shown in FIG. 4, the x-y coordinates “(35,29)” of the date CH 7  in the type A of the video-scope  10  is different from the x-y coordinates “(26,30)” of the date CH 7  in the type B of the video-scope  10 , though the display-position of the date CH 7  in the type A of the video-scope  10  and the display-position of the date CH  7  in the type B of the video-scope  10  are substantially the same on the screen W, as shown in the pictures P 1 ′ and P 2 ′ of FIG.  2 . 
     FIG. 5 is a view showing a main routine regarding operations of the electronic endoscope as a whole. When electric power is turned ON, the main routine is started. 
     In Step  101 , the x-y coordinates (x,y) stored in the array H, the stop  25  and so on, are subjected to an initial setting, respectively. 
     In Step  102 , a processing regarding a displaying of the time and the date is performed. In Step  103 , a processing regarding the video-scope  10  is performed. In Step  104 , other processing, for example, a level of the brightness of the light source  19  is adjusted in accordance with the operation of the panel switches  27 . 
     These operations of the electronic endoscope are executed until the electric power is turned OFF. In Steps  102  to  104 , subroutines, as described later, are respectively performed. 
     FIG. 6 is a view showing an interrupt routine regarding the operation of the keyboard  26 , as described later. This interrupt processing interrupts the operations of the electronic endoscope shown in FIG.  5 . 
     FIG. 7 is a subroutine of Step  102  in FIG.  5 . 
     In Step  201 , it is determined whether or not data regarding the time and the date, read from the RTC  31 , has changed compared to a preceding date and time, read at a preceding processing. Namely, it is determined whether or not one second has passed compared to the preceding processing. When the time has passed by more than one second, the process goes to Step  202 . On the other hand, when the time has not passed by more than one second, this subroutine is terminated. 
     In Step  202 , the date (a year, a month, a day) CH 7  is displayed on the screen W on the basis of the x-y coordinates (x,y) stored in the array H. For example, when the type A of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, the date CH 7  is displayed such that a head numeral “1” in the date CH 7  is located at (24,9), as shown in FIG.  2 . Note that, the x-coordinate “24”and the y-coordinate “9” is respectively stored in the array H[7,1] and the array H[7,2]. 
     In Step  203 , the real time (hour, minute, second) CH 8  is displayed on the screen W on the basis of the x-y coordinates (x,y) stored in the array H, similarly to the date CH 8 . After the time and the date are displayed at the determined position, this subroutine is terminated, and the process then returns to Step  102  of FIG.  5 . 
     FIG. 8 is a view showing a subroutine of Step  103  in FIG.  5 . 
     In Step  301 , it is determined whether or not the video-scope  10  is newly connected to the video-processor  20 . When it is determined that the video-scope  10  is newly connected to the video-processor  20 , namely, the exchange of the video-scope  10  has been performed, the process goes to Step  302 . 
     In Step  302 , it is determined whether the video-scope  10 , which has been newly connected to the video-processor  20 , is the type A of the video-scope  10 . Note that, this determination is based on the data, read from the EEPROM  19  in the video-scope  10  (shown in FIG.  1 ). When it is determined that the connected video-scope  10  is the type A, the process goes to Step  303 . 
     In Step  303 , it is determined whether or not a display variable vr is 0. Namely, it is determined whether the display-state before the exchange of the video-scope  10  is the normal-display. The display variable vr indicates the normal-display or the magnification-display. When the display variable vr is 1, the display-state is the magnification-display, while, when the display variable vr is 0, the display-state is the normal-display. 
     When it is determined that the display variable vr is 0 at Step  303 , the process goes to Step  304 . 
     In Step  304 , the object image is displayed within the image-area IA. Further, the display-positions of the character information are determined from the reference table T. Namely, the x-y coordinates (x,y) stored in the array h[cp,1] and the array h[cp,2], corresponding to the type A of the video-scope  10  and the normal-display, is read, and then temporarily stored in the array H[cp,1] and the array H[cp,2]. Then, the process goes to Step  305 . 
     In Step  305 , each item of character information is displayed at the determined position on the basis of the x-y coordinates (x,y) stored in the array H[cp,1] and the array H[cp,2], as shown in the picture P 1  displayed on the screen W in FIG.  2 . At this time, the scope-name of the type A of video-scope  10 .is displayed. After the character information is displayed, this subroutine is terminated, and then the process returns to Step  103  in FIG.  5 . 
     When it is determined that the display variable vr is 1 at Step  303 , namely, the display-state is the magnification-display, the process goes to Step  306 . 
     In Step  306 , the object image is displayed within the image-area IA′. Further, the display-positions of the character information are determined, similarly to Step  304 . Note that, in this case, the x-y coordinates (x,y), stored in the array h[cp,3] and the array h[cp,4], corresponding to the type A of the video-scope  10  and magnification-display, is read and then temporarily stored in the array H[cp,1] and the array H[cp,2]. Then, the process goes to Step  307 . 
     In Step  307 , each item of character information is displayed at the determined position on the basis of the x-y coordinates (x,y) stored in the array H[cp,1] and the array H[cp,2], as shown in the picture P 1 ′ displayed on the screen W in FIG.  2 . After the character information is displayed, this subroutine is terminated, and then the process returns to Step  103  in FIG.  5 . 
     On the other hand, when it is determined that type B of the video-scope  10  is newly connected to the video-processor  20  at Step  302 , the process goes to Step  308 . 
     In Step  308 , it is determined whether or not the display variable vr is 0. When it is determined that the display variable vr is 0, namely, the display-state is the normal-display, the process goes to Step  309 . 
     In Step  309 , the object image is displayed within the image-area IB. Further, the display-positions of the character information are determined from the reference table T. Namely, the x-y coordinates (x,y) stored in the array h[cp,5]and the array h[cp,6], corresponding to the type B of the video-scope  10  and the normal-display, is read, and then temporarily stored in the array H[cp,1] and the array H[cp,2]. Then, the process goes to Step  310 . 
     In Step  310 , each item of character information is displayed at the determined position on the basis of the x-y coordinates (x,y) stored in the array H[cp,1] and the array H[cp,2], as shown in the picture P 2  displayed on the screen W in FIG.  2 . At this time, the scope-name of the type B of video-scope  10  is displayed. After the character information is displayed, this subroutine is terminated, and then the process returns to Step  103  in FIG.  5 . 
     When it is determined that the display variable vr is 1 at Step  308 , namely, the display-state is magnification-display, the process goes to Step  311 . 
     In Step  311 , the object image is displayed within the image-area IB′. Further, the display-positions of the character information are determined, similarly to Step  309 . Note that, in this case, the x-y coordinates (x,y) stored in the array h[cp,7] and the array h[cp,8], corresponding to the type B of the video-scope  10  and magnification-display, is read and then temporary stored in the array H[cp,l] and the array H[cp,2]. Then, the process goes to Step  312 . 
     In Step  312 , each of character information is displayed at the determined position on the basis of the x-y coordinates (x,y) stored in the array H[cp,1] and the array H[cp,2]), as shown in the picture P 2 ′ displayed on the screen W in FIG.  2 . After the character information is displayed, this subroutine is terminated, and then the process returns to Step  103  in FIG.  5 . 
     When it is determined that the video-scope  10  is not newly connected to the video-processor  20  at Step  301 , the process goes to Step  313 . 
     In Step  313 , it is determined whether the video-scope  10  is detached from the video-processor  20 . 
     When it is determined that the video-scope  10  is detached from the video-processor  20 , the process goes to Step  314 . In Step  314 , the object image and the scope-name of the video-scope  10  are erased from the screen W. At this time, the object image is not displayed on the screen W. Then, this subroutine is terminated and the process returns to Step  103  of FIG.  5 . 
     On the other hand, when it is determined that the video-scope  10  is not detached from the video-processor  20 , namely, the video-scope  10  is not changed, the subroutine is terminated and then the process returns to Step  103  of FIG.  5 . 
     As mentioned above, when the exchange of the video-scope  10  is performed, the display-positions of the character information are determined depending upon the corresponding x-y coordinates (x,y) stored in the array h. 
     FIG. 9 is a view showing the interrupt routine of FIG. 6 in detail. When any key on the keyboard  26  is operated, this routine is started. 
     In Step  401 , it is determined whether the pointer display variable vm is 0, namely, whether the pointer P is not displayed on the screen W of the monitor  49 . Note that, the pointer display variable vm is 1 when the pointer P is displayed, while the pointer display variable vm is 0 when the pointer P is not displayed. When the keyboard  26  is manipulated while the pointer P is displayed on the screen W, Steps  415  to  427  are performed. On the other hand, when the keyboard  26  is manipulated while the pointer P is not displayed on the screen W, Steps  402  to  414  are performed. 
     When it is determined that the pointer display variable vm is 0 at Step  401 , the process goes to Step  402 . 
     In Step  402 , it is determined whether or not one of the character keys  54  (shown in FIG. 3) on the keyboard  26  is operated by the operator. When it is determined that one of the character keys  54  is operated, the process goes to Step  403 , wherein a processing corresponding to the character keys  54  is performed. Then, this interrupt routine is terminated. On the other hand, when it is determined that none of the character keys  54  are operated at Step  402 , the process goes to Step  404 . 
     In Step  404 , it is determined whether or not the Enter key  51  (shown in FIG. 3) on the keyboard  26  is operated by the operator. When it is determined that the Enter key  53  is operated, the process goes to Step  405 , wherein a processing corresponding to the Enter key  53  is performed. Then, this interrupt routine is terminated. On the other hand, when it is determined that the Enter key  53  is not operated at Step  404 , the process goes to Step  406 . 
     In Step  406 , it is determined whether or not the up-shift key  50 U (shown in FIG. 3) on the keyboard  26  is operated. When it is determined that the up-shift key  50 U is operated, the process goes to Step  407 , wherein a processing corresponding to the up-shift key  50 U is performed. Then, this interrupt routine is terminated. On the other hand, when it is determined that the up-shift key  50 U is not operated at Step  406 , the process goes to Step  408 . 
     In Step  408 , it is determined whether or not the down-shift key  50 D (shown in FIG. 3) on the keyboard  26  is operated. When it is determined that the down-shift key  50 D is operated, the process goes to Step  409 , wherein a processing identical to Step  405  is performed. Then, this routine is terminated. On the other hand, when it is determined that the down-shift key  50 D is not operated at Step  408 , the process goes to Step  410 . 
     In Step  410 , it is determined whether or not the F 4  key  53  (shown in FIG. 3) on the keyboard  26  is operated. When it is determined that the F 4  key  53  is operated, the process goes to Step  411 , wherein a processing corresponding to the F 4  key  53  is performed. Then, the interrupt routine is terminated. On the other hand, when it is determined that the F 4  key  53  is not operated at Step  410 , the process goes to Step  412 . 
     In Step  412 , it is determined whether or not the F 8  key  52  (shown in FIG. 3) on the keyboard  26  is operated. When it is determined that the F 8  key  52  is operated, the process goes to Step  413 , wherein a processing corresponding to the F 8  key  52  is performed. Then, the interrupt routine is terminated. On the other hand, when it is determined that the F 8  key  52  is not operated at Step  412 , the process goes to Step  414 . 
     In Step  414 , a processing regarding other keys (for example, ESC key) on the keyboard  26  is performed. Then, this interrupt routine is finished. 
     When it is determined that the pointer display variable vm is 1 at Step  401 , namely, the pointer P is displayed on the screen W, the process goes to Step  415 . 
     In Step  415 , it is determined whether or not the up-shift key  50 U on the keyboard  26  is operated. When it is determined that the up-shift key  50 U is operated, the process goes to Step  416 . 
     In Step  416 , the pointer P is shifted upward along a y-direction by one coordinate worth only when a following formula (5) is satisfied regarding the display-position of the pointer P. 
     
       
         vy&gt;H[9,2]  (5) 
       
     
     Note that, a value of the y-coordinate of the pointer P is denoted by “vy”, and the y-coordinate of the minimum limitation-position of the pointer A min  is stored in the array H[9,2]). For example, when the type A of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, as shown in FIG. 4, the formula (6), which corresponds to the formula (5), is: 
     
       
         vy&gt;2  (6) 
       
     
     When the formula (5) is satisfied, the pointer P is shifted upward by one coordinate worth. In other words, the value of the y-coordinate vy is decremented by 1. For example, the pointer P, the y-coordinate of which is “20”, is shifted to the position of y-coordinate “19”. If the formula (5) is not satisfied, the pointer P is not shifted such that the display-position of the pointer P remains within the image-area. After Step  416  is executed, the interrupt routine is terminated. 
     On the other hand, when it is determined that the up-shift key  50 U is not operated at Step  415 , the process goes to Step  417 . 
     In Step  417 , it is determined whether or not the down-shift key  50 D in the keyboard  26  is operated. When it is determined that the down-shift key  50 D is operated, the process goes to Step  418 . 
     In Step  418 , the pointer P is shifted downward along the y-direction by one coordinate worth only when a following formula (7) is satisfied regarding the display-position of the pointer P. 
     
       
         vy&lt;H[10,2]  (7) 
       
     
     The y-coordinate of the maximum limitation-position of the pointer A max  is stored in the array H[10,2]. For example, when the type A of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, formula (8), which corresponds to the formula (7), is: 
     
       
         vy&lt;23  (8) 
       
     
     When the formula (7) is satisfied, the pointer P is shifted downward by one coordinate worth. In other words, the value of the y-coordinate vy is incremented by 1. For example, the pointer P, the y-coordinate of which is “20”, is shifted to the position of the y-coordinate “21”. If the formula (7) is not satisfied, the pointer P is not shifted. After Step  418  is executed, the interrupt routine is terminated. 
     On the other hand, when it is determined that the down-shift key  50 D is not operated at Step  417 , the process goes to Step  419 . 
     In Step  419 , it is determined whether or not the left-shift key  50 L in the keyboard  26  is operated. When it is determined that the left-shift key  50 L is operated, the process goes to Step  420 . 
     In Step  420 , the pointer P is shifted leftward along a x-direction by one coordinate worth, only when a following formula (9) is satisfied regarding the display-position of the pointer P. 
     
       
         vx&gt;H[9,1]  (9) 
       
     
     A value of the x-coordinate of the pointer P is denoted by “vx”, and the x-coordinate of the minimum limitation-position of the pointer A min  is stored in the array H[9,1]. For example, when the type A of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, as shown in FIG. 4, formula (10), which corresponds to the formula (9), is: 
     
       
         vx&gt;0  (10) 
       
     
     When the formula (9) is satisfied, the pointer P is shifted leftward by one coordinate worth. In other words, the value of the x-coordinate “vx” is decremented by 1. For example, the pointer P, the x-coordinate of which is “17”, is shifted to the position of x-coordinate “16”. If the formula (9) is not satisfied, the pointer P is not shifted. After Step  420  is executed, the interrupt routine is terminated. 
     On the other hand, when it is determined that the left-shift key  50 L is not operated at Step  419 , the process goes to Step  421 . 
     In Step  421 , it is determined whether or not the right-shift key  50 R in the keyboard  26  is operated. When it is determined that the right-shift key  50 R is operated, the process goes to Step  422 . 
     In Step  422 , the pointer P is shifted rightward along the x-direction by one coordinate worth only when a following formula (11) is satisfied regarding the display-position of the pointer P. 
     
       
         vx&lt;H[10,1]  (11) 
       
     
     The x-coordinate of the minimum-limitation-position of the pointer A max  is stored in the array H[10,1]. For example, when the type A of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, formula (12), corresponds to the formula (11), is: 
      vx&lt;18  (12) 
     When the formula (11) is satisfied, the pointer P is shifted rightward by one coordinate worth. In other words, the value of the x-coordinate vx is incremented by 1. For example, the pointer P, the x-coordinate of which is “15”, is shifted to the position of the x-coordinate “16”. If the formula (11) is not satisfied, the pointer P is not shifted. After Step  422  is executed, the interrupt routine is terminated. 
     On the other hand, when it is determined that the right-shift key  5 OR is not operated at Step  421 , the process goes to Step  423 . 
     In Step  423 , it is determined whether or not the F 4  key  53  on the keyboard  26  is operated. When it is determined that the F 4  key  53  is operated, the process goes to Step  424 , wherein the pointer P is erased from the screen W of the monitor  49 , and further the pointer display variable vm is set to 0. Then, the interrupt routine is terminated. On the other hand, when it is determined that the F 4  key  53  is not operated at Step  423 , the process goes to Step  425 . 
     In Step  425 , it is determined whether or not the F 8  key  52  on the keyboard  26  is operated. When it is determined that the F 8  key  52  is operated, the process goes to Step  426 , wherein a processing corresponding to the F 8  key  52  is performed. Then, the interrupt routine is terminated. On the other hand, when it is determined that the F 8  key  52  is not operated at Step  425 , the process goes to Step  427 . In Step  427 , the process equal to Step  414  is performed, and then the interrupt routine is terminated. Note that, in Step  426 , as described later, the display-position of the pointer P is adjusted. 
     As mentioned above, the process for operating the keyboard  26  is performed at Steps  401  to  427 . Then, as described later, subroutines are performed at Steps  403 ,  405 ,  407 ,  409 ,  411 ,  413 ,  426 , respectively. 
     FIG. 10 is a subroutine of Step  403  in FIG.  9 . This subroutine is performed when one of the character keys  54  is depressed. 
     In Step  501 , it is determined whether the item variable cp is 0, namely, whether the cursor C is not displayed on the monitor  46 . The item variables 1 to 6 correspond to the patient&#39;s name CH 1  through to the scope-name CH 6  of the character information respectively. When the item variable cp is 0, the cursor C is not displayed. 
     When it is determined that the item variable cp is not 0, the process goes to Step  502 . 
     In Step  502 , a letter corresponding to the depressed character key among the character keys  54  is input at a position corresponding to the display-position of the cursor C. Then, at Step  503 , a cursor position variable cu is incremented by 1, thus the cursor C is shifted rightward by one letter worth Note that, the cursor position variable cu corresponds to a cursor&#39;s display-position in each item of the character information. Further note that, the cursor C is located at the head letter in each of the character information when the cursor position variable cu is 0, as shown in the picture P 1  of FIG.  2 . After the letter is input and the cursor C is shifted, the subroutine is terminated and then the process returns to Step  403  in FIG.  9 . 
     In this way, the character information is rewritten by operating the character keys  54 . 
     On the other hand, when it is determined that the item variable cp is 0 at Step  501 , this subroutine is terminated and the process returns to Step  403  in FIG.  9 . 
     FIG. 11 is a &#39;subroutine of Steps  405  and  409  in FIG.  9 . As described above, this subroutine is performed when the Enter key  51  or the up-shift key  50 U is depressed. 
     In Step  601 , it is determined whether the item variable cp is 6, namely, whether the cursor C is located at the scope-name of the video-scope CH 6  on the screen W. When it is determined that the item variable cp is 6, the process goes to Step  602 , wherein the item variable cp is set to 0. Then the process goes to Step  604 . 
     On the other hand, when it is determined that the item variable cp is not 6 at Step  601 , the process goes to Step  603 , wherein the item variable cp is incremented by 1. For example, when the item variable cp is 5 corresponding to the doctor&#39;s name CH 5 , the item variable cp is set to 6, corresponding to the scope-name CH 6 . Then, the process goes to Step  604 . 
     In Step  604 , the cursor C is shifted to a position of the item corresponding to the item variable cp, which is set to at Step  602  or Step  603 , and further the cursor position variable cu is set to 0. Namely, the cursor C is shifted to the head letter in the item corresponding to the item variable cp, which is set at Step  602  or  603 . 
     FIG. 12 is a subroutine of Step  604  in FIG.  11 . 
     In Step  701 , it is determined whether or not the item variable cp is 0, namely, whether the item variable cp is set to 0 at Step  602  in FIG.  11 . When it is determined that the item variable cp is 0, the process goes to Step  702 , wherein the cursor C is erased from the screen W of the monitor  46 . Then, this subroutine is terminated. On the other hand, when it is determined that the item variable cp is not 0, the process goes to Step  703 . 
     In Step  703 , it is determined whether or not the item variable cp is 1, namely, whether the item variable cp is set to 1 at Step  603  in FIG.  11 . When it is determined that the item variable cp is 1, the process goes to Step  704 , wherein the cursor C is displayed at the position corresponding to the head letter in the patent&#39;s name CH 1 . Note that, the x-y coordinates (x,y) of the head letter position is stored in the array H. For example, when the type B of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, as shown in the picture P 2  of FIG. 2, the x-y coordinates (x,y ) of the position of the cursor C is: 
     
       
         (x,y)=(H[1,1], H[1,2])=(1,1)  (13) 
       
     
     After Step  704  is performed, this subroutine is terminated. 
     On the other hand, when it is determined that the item variable cp is not 1 at Step  703 , the process goes to Step  705 . 
     In Steps  705  to  714 , the value of the item variable cp is determined, similarly to Step  703 , and then the cursor C is displayed depending upon the item variable cp, similarly to Step  704 . Note that, the display-position of the cursor C is in accordance with the x-y coordinates (x,y) stored in the array H as following: 
     
       
         (x,y)=(H[cp,1].H[cp,2])  (14) 
       
     
     For example, when it is determined that the item variable cp is 3 at Step  707  in a case where the type A of the video-scope  10  is connected to the video-processor  20  and the display-state is the normal-display, as shown in the picture P 1  of FIG. 2, the cursor C is displayed at following display-position at Step  708 : 
     
       
         (X,y)=(H[3,1],H[3,2])=(24,2)  (15) 
       
     
     In this way, the cursor C is shifted to the head letter in the next item when the Enter key  51  or the down-shift key  50 D is depressed. For example, when the Enter key  51  is depressed in a case where the cursor C is located at the doctor&#39;s name CH 5 , the cursor C is shifted to the head letter in the scope-name CH 6 . At this time, the display-position of the cursor C is determined in accordance with the x-y coordinates (x,y) stored in the array H. After the cursor C is displayed at the determined position, this subroutine is terminated, and the process returns to Step  604  in FIG.  10 . 
     FIG. 13 is a subroutine of Step  407  in FIG.  9 . As described above, this subroutine is performed when the up-shift key  50 U is depressed. 
     In Step  801 , it is determined whether or not the item variable cp is 0, namely, whether the cursor C is not displayed on the screen W. When it is determined that the item variable cp is 0, the process goes to Step  802 , wherein the item variable cp is set to 6. Then, the process proceeds to Step  804 . 
     On the other hand, when it is determined that the item variable cp is not 0, the process goes to Step  803 , wherein the item variable cp is decremented by 1. For example, when the item variable cp is 5 corresponding to the doctor&#39;s name CH 5 , the item variable cp is set to 4, corresponding to the patient&#39;s sex CH 4 . Then, the process proceeds to Step  804 . 
     In Step  804 , the cursor C is shifted to the item corresponding to the item variable cp, which is set at Step  802  or  803 . Then, the cursor position variable cu is set to 0. Namely, the cursor C is displayed at a position corresponding to the head letter in the character information. Note that, Steps  701  to  714  shown in FIG. 11 is performed at Step  804 , similarly to Step  604  in FIG.  12 . After the cursor C is shifted, this subroutine is terminated and then the process returns to Step  407  in FIG.  9 . 
     In this way, the cursor C is shifted to the head letter in the next item when the up-shift key SOU is depressed, similarly to the Enter key  51  or the down-shift key  50 D. Note, the shifting-direction of the up-shift key  50 U is opposite to the shifting-direction of the Enter key  51  or the down-shift key SOD. 
     FIG. 14 is a subroutine of Steps  413  and  426  in FIG.  9 . As described above, this subroutine is performed when the F 8  key  52  is depressed. 
     In Step  901 , it is determined whether or not the display variable vr is 0, namely, whether the F 8  key  52  on the keyboard  26  is depressed when the display-state is the normal-display. When it is determined that the display variable vr is 0, the process goes to Step  902 . 
     In Step  902 , the display variable vr is set to 1, namely, the display-state is changed to the magnification-display. Then, the process proceeds to Step  903 . 
     In Step  903 , it is determined whether or not the type A of the video-scope  10  is connected to the video-processor  20 . When it is determined that the type A of the video-scope  10  is connected to the video-processor  20 , the process goes to Step  904 . 
     In Step  904 , the object image is displayed within the magnifying image-area IA′, as shown in the picture P 1 ′ of FIG.  2 . Further, the x-y coordinates (x,y) of the character information are determined on the basis of the reference table T. Namely, the x-y coordinates (x,y), corresponding to the type A of the video-scope  10  and the magnification-display, are read from the array h, and then temporarily stored in the array H. In this case, the x-y coordinates (x,y) are: 
     
       
         (x,y)=(h[cp,3],h[cp,4])  (16) 
       
     
     The above x-y coordinates (x,y) are temporarily stored in the array H [cp,1] and the array H [cp,2]. Then, the process proceeds to Step  910 . 
     On the other hand, when it is determined that the type B of the video-scope  10  is connected to the video-processor  20  at Step  903 , the process goes to Step  905 . 
     In Step  905 , the object image is displayed within the magnifying image-area IB′ , as shown in the picture P 2 ′ of FIG.  2 . Further, the x-y coordinates (x,y) of the character information are determined on the basis of the reference table T. Namely, the x-y coordinates (x,y), corresponding to the type B of the video-scope  10  and the magnification-display, are read from the array h, and then temporarily stored in the array H. In this case, the x-y coordinates (x,y) are: 
     
       
         (x,y)=(h[cp,7],h[cp,8])  (17) 
       
     
     The above x-y coordinates (x,y) are temporarily stored in the array H [cp,1] and the array H [cp,2]. Then, the process proceeds to Step  910 . 
     When it is determined that the display variable vr is 1 at Step  901 , namely, whether the F 8  key  52  on the keyboard  26  is depressed when the display-state is the magnification-display (vr=1), the process goes to Step  906 . 
     In Step  906 , the display variable vr is set to 0, namely, the display-state is changed to the normal-display. Then, the process proceeds to Step  907 . 
     In Step  907 , it is determined whether or not type A of the video-scope  10  is connected to the video-processor  20 . When it is determined that the type A of the video-scope  10  is connected to the video-processor  20 , the process goes to Step  908 . 
     In Step  908 , the object image is displayed within the normal image-area IA, as shown in the picture P 1  of FIG.  2 . Further, the x-y coordinates (x,y) of the character information are determined on the basis of the reference table T. Namely, the x-y coordinates (x,y), corresponding to the type A of the video-scope  10  and the normal-display, are read from the array h , and then temporarily stored in the array H. In this case, the x-y coordinates (x,y) are: 
     
       
         (x,y)=(h[cp,1],h[cp,2])  (18) 
       
     
     The above x-y coordinates (x,y) are temporarily stored in the array H [cp,1] and the H [cp,2]. Then, the process proceeds to Step  910 . 
     On the other hand, when it is determined that the type A of the video-scope  10  is not connected to the video-processor  20  at Step  907 , the process goes to Step  909 . 
     In Step  909 , the object image is displayed within the normal image-area IB, as shown in the picture P 2  of FIG.  2 . Further, the x-y coordinates (x,y) are determined on the basis of the reference table T. Namely, the x-y coordinates (x,y), corresponding to the type B of the video-scope  10  and the normal-display, are read from the array h, and then temporarily stored in the array H. In this case, the x-y coordinates (x,y) are: 
     
       
         (x,y)=(h[cp,5],h[cp,6])  (19) 
       
     
     The above x-y coordinates (x,y) are temporarily stored in the array H[cp,1] and the array H [cp,2]. Then, the process proceeds to Step  910 . 
     In Step  910 , all of the character information, displayed on the screen W before the depression of the F 8  key  52 , is erased from the screen W. Then, at Step  911 , each of the character information is newly displayed at the determined position in accordance with the x-y coordinates (x,y), set at one of Step  904 , Step  905 , Step  908  and Step  909 . After the character information is newly displayed, this subroutine is terminated. 
     FIG. 15 is a subroutine of Step  411  in FIG. . 9 . 
     This subroutine is performed when the F 4  key  53  is depressed. Further, this subroutine is also performed when Step  426  in FIG.  9  and Step  103  in FIG. 5 are performed. Namely, Steps  951  to  954  are performed when the exchange of the video-scope  10  is performed or when the change of the image-area is executed. Herein, the subroutine is referred to as “pointer subroutine”. 
     At Step  951 , it is determined whether or not the pointer P can be displayed within the image-area. Namely, it is determined whether or not a display-position, at which the pointer P is displayed before the erasing by the F 4  key  53 , the exchange of the video-scope or the change of the image-area, is within the image-area. Step  951  is performed on the basis of the x-y coordinates (x,y) stored in the array H[9,1], the array H[9,2] and the array H [10,1], the array H[10,2]. 
     When it is determined that the pointer P can be displayed within the image-area, the process goes to Step  952 , wherein the pointer P is displayed as before. Then, the process proceeds to Step  954 . 
     On the other hand, when it is determined that the pointer P cannot be displayed within the image-area at Step  951 , the display-position of the pointer P is changed such that the pointer P can be displayed within the image-area, at Step  953 . 
     For example, when the magnification-display is changed to the normal-display by depressing the F 8  key  52  when the type B of the video-scope  10  is connected to the video-processor  20  and the pointer P is displayed at a position of ( 28 , 15 ), within in the image-area IB′, Step  951  is performed on the basis of the x-y coordinates (x,y) stored in the array H[9,1], the array H[9,2] and the array H[10,1], the array H[10,2], corresponding to the x-y coordinates (x,y) stored in the array h[9,5], the array h[9,6] and the array h[10,5], the array h[10,6] (See FIG.  4 ). As the display-position of ( 28 , 15 ) is beyond the normal-image-area IB, the pointer P is shifted to a position of ( 21 , 15 ) on the basis of the x-coordinate “21”stored in the array H [10,1], so that the pointer P is displayed on the boundary of the image-area IB. After the pointer P is shifted at Step  953 , the process goes to Step  954 . 
     In Step  954 , the pointer display variable vm is set to 1, which indicates that the pointer P is displayed, and then the pointer subroutine is terminated. 
     As described above, the display-positions of the character information and the pointer P are adjusted in accordance with the size-change of the image-area. The display-positions of the character information are adjusted in accordance with the exchange of the video-scope, as shown at Steps  301  to  312  in FIG. 8, and in accordance with the size-change of the image-area, as shown at Steps  901  to  911  in FIG.  14 . Also, the display-position of the pointer P is adjusted as shown at Steps  951  to  954  in FIG.  15 . 
     Generally, in the conventional electronic endoscope, when the display-position of each item is determined, processing, which determines the type of the video-scope and determines whether the display-state is the normal-display or the magnification-display, is performed for each item, one by one. For example, after the display-position of the patient&#39;s name CH 1  is determined by performing the above process, the display-position of the ID number CH 2  is determined by performing the processing, similarly to the patient&#39;s name CH 1 . 
     On the other hand, in this embodiment, the display-positions of the character information (all of items) and the pointer P are determined from the reference table T. At this time, the corresponding x-y coordinates (x,y) of the character information and the pointer P, stored in the array h (ROM  33 ), are read and then temporarily stored in the array H (RAM  34 ). Thus, each item of the character information is displayed in accordance with the x-y coordinates (x,y) stored in the array H, and further the display-position of the pointer P is adjusted on the basis of the x-y coordinates (x,y) stored in the array H. Namely, the character information and the pointer P can be displayed without performing a processing, which determines the type of the video-scope  10  and further determines the display-state by each item. As a consequence, the processing-speed regarding a displaying of the character information and the pointer P improves. 
     As described above, generally, when the display-state is the magnification-display, the number of letters, which can be displayed in each column on the screen W, of the type A of the video-scope  10  is different from that of the type B of the video-scope  10 . Namely, the x-y coordinates (x,y) of the character information and the pointer P are different depending upon the type of the video-scope  10  in a case where the display-state is the magnification-display. Accordingly, when the input of the letter and the shifting of the position of the cursor C and the pointer P are performed, the x-y coordinates (x,y) of the inputted letter, the cursor C and the pointer P are different depending upon the type of the video-scope  10 . Therefore, conventionally, the type of the video-scope  10  is determined and the display-state is determined every time the letter is newly rewritten, the cursor C is shifted, or the pointer P is shifted. 
     However, in this embodiment, when the input of the letter and the shifting of the position of the cursor C and the pointer P are performed, the x-y coordinates (x,y) of the character information and the pointer P, corresponding to the image-area selected by the operator, is stored in the RAM  34 , in short, the array H. Thus, the input of the letter and the shifting of the position of the cursor C and the pointer P are performed without performing the processing, which determines the type of the video-scope  10  and determines the display-state. 
     In a modification, only character information may be displayed on the basis of the reference table T. 
     Finally, it will be understood by those skilled in the art that the foregoing description is of preferred embodiment of the device, and that various changes and modifications may be made to the present invention without departing from the spirit and scope thereof. 
     The present disclosure relates to subject matters contained in Japanese Patent Application No. 10-370172 (filed on Dec. 25, 1998) which is expressly incorporated herein, by reference, in its entirety.