Abstract:
A surgical microscope system includes a camera  20.  The camera  20  includes CCDs  21  and a focusing mechanism ( 41, 42, 43 ). If an image displayed on an electronic image display unit  5  is unclear due to a focusing error, the focusing mechanism is operated to focus the image and make the image clearly visible. Without regard to a focusing operation conducted by a doctor D 1  on a surgical microscope  4,  an assistant D 2  on the electronic image display unit is able to manipulate the focusing mechanism and observe clear images on the electronic image display unit.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a surgical microscope system. 
         [0003]    2. Description of Related Art 
         [0004]    The surgical microscope system typically includes a surgical microscope, a camera, and an electronic image display unit. The surgical microscope is installed on a medical stand and is vertically movable on the medical stand. The camera is installed on the surgical microscope and picks up a pair of electronic images of an affected part or a target part of a patient, the electronic images having binocular parallax to realize a stereoscopic view. The electronic image display unit includes a pair of left and right display panels to display the pair of electronic images, respectively, so that an observer may see a stereoscopic image of the target part through a pair of left and right eyepiece parts of the display unit. A related art is disclosed in, for example, Japanese Unexamined Patent Application Publication No. 2004-320722. 
       SUMMARY OF THE INVENTION 
       [0005]    According to the related art, an operator of the surgical microscope conducts a focusing action by manipulating an internal optical system of the surgical microscope and an action of adjusting the surgical microscope to a focal point of the observer&#39;s eye by vertically moving the surgical microscope on the medical stand. Vertically moving the surgical microscope frequently results in breaking the focused state of the internal optical system of the surgical microscope and displaying unfocused images on the display panels of the electronic image display unit. If this happens, the observer of the display unit sees unclear images. 
         [0006]    In consideration of this problem, the present invention provides a surgical microscope system having a surgical microscope, a camera, and an electronic image display unit, capable of displaying clear images on the electronic image display unit irrespective of an internal out-of-focus condition of the surgical microscope. 
         [0007]    According to an aspect of the present invention, the surgical microscope system includes a surgical microscope that is vertically movably supported and has an objective optical system, variable-power optical systems, and a pair of left and right eyepiece parts to form two main optical paths, at least one of the main optical paths being branched into a sub-optical path. A camera is installed on the surgical microscope and has a pair of left and right imaging elements to receive light from the sub-optical path and provide electronic images. An electronic image display unit has a pair of left and right display panels to display the electronic images provided by the camera and a pair of eyepiece parts through which an observer is able to observe the displayed images with his or her eyes, respectively. And a focusing mechanism is arranged for the imaging elements in the camera. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a perspective view illustrating a surgical microscope system according to a first embodiment of the present invention; 
           [0009]      FIGS. 2 and 3  are views illustrating an internal structure of a surgical microscope of the surgical microscope system; 
           [0010]      FIG. 4  is a view explaining optical systems of the surgical microscope; 
           [0011]      FIG. 5  is a view illustrating a relationship between a camera and an electronic image display unit of the surgical microscope system; 
           [0012]      FIG. 6  is a sectional view illustrating an internal structure of the camera; 
           [0013]      FIG. 7  is a view illustrating filters arranged in the camera; 
           [0014]      FIGS. 8 and 9  are views illustrating an internal structure of the electronic image display unit; 
           [0015]      FIG. 10  is a perspective view illustrating a surgical microscope and a camera of a surgical microscope system according to a second embodiment of the present invention; 
           [0016]      FIG. 11  is a perspective view illustrating an internal structure of the surgical microscope of  FIG. 10 ; and 
           [0017]      FIG. 12  is a sectional view illustrating an internal structure of the camera of  FIG. 10 . 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     First Embodiment 
       [0018]    A surgical microscope system according to the first embodiment of the present invention will be explained with reference to  FIGS. 1 to 9 . 
         [0019]    In  FIG. 1 , a support arm  1  horizontally extends from a medical stand (not illustrated) arranged in an operating room. A front end  2  of the support arm  1  is attached to a suspension aim  3  having a U-shape. A lower end of the suspension aim  3  supports a surgical microscope  4  manipulated by a doctor D 1 . 
         [0020]    On the right side of the surgical microscope  4 , an electronic image display unit  5  is supported with a support arm  6  that extends from the front end  2  of the support aim  1 . The display unit  5  is manipulated by an assistant D 2  who is on the right side of the doctor D 1 . 
         [0021]    The surgical microscope  4  allows a stereoscopic observation. For this, left and right main optical paths A each is defined inside the surgical microscope  4 . At a lower part of the surgical microscope  4 , a light inlet  7  is formed. Above the light inlet  7 , an objective optical system  8  having lens groups is vertically arranged. Above the objective optical system  8 , prisms  9  are arranged. Arranged behind the prisms  9  are horizontal variable-power optical systems  10  having lens groups. 
         [0022]    Behind the variable-power optical systems  10 , beam splitters  11  and prisms  12  are vertically arranged to upwardly and then forwardly bend the optical paths A. The optical paths A pass through imaging optical systems  13  to form primary images F 1  and reach eyepiece parts  14 . The eyepiece parts  14  have eyepiece optical systems  15 , respectively, through which the doctor D 1  optically three-dimensionally observes the primary images F 1 . 
         [0023]    As illustrated in  FIG. 4 , light L from an affected part, i.e., a target part T of a patient is guided at a convergence angle “θ (theta)” into the objective optical system  8 . The light L is divided by the objective optical system  8  into the two optical paths A that are guided through the prisms  9  and the like to the pair of left and right eyepiece parts  14  for the left and right eyes of the doctor D 1 . Due to the convergence angle “θ (theta)”, the primary images F 1  from the eyepiece parts  14  involve binocular parallax, and therefore, are stereoscopically observable. 
         [0024]    The main optical paths A are split by the beam splitters  11  into sub-optical paths B, respectively. As illustrated in  FIGS. 3 and 5 , the sub-optical paths B pass through prisms  16 , lenses  17 , relay lenses  18 , and parallelogram prisms  19  to a camera  20  installed on the surgical microscope  4 . 
         [0025]    The camera  20  incorporates a pair of left and right CCD image sensors (hereinafter referred to as “CCDs”)  21  that are two-dimensional photographing elements. The CCDs  21  pick up a pair of electronic images having binocular parallax. In front of the CCDs  21 , focus adjustment lenses  41  and  42  are arranged. Among them, the lenses  42  are moved by a servo mechanism  43 . The lenses  41  and  42  and servo mechanism  43  form the “focusing mechanism” stipulated in the claims. 
         [0026]    In front of the lenses  41  and  42 , a rotary plate  44  is arranged. The rotary plate  44  has four holes in which a pair of transmission observation glasses (having an infrared cutting function)  45  and a pair of fluorescence observation filters  46  are arranged. The filters  46  are band-pass filters to selectively transmit light of a predetermined wavelength band depending on a fluorescent material. The rotary plate  44  is turned by a motor  47  to select the transmission glasses  45  or the filters  46 . The electronic images picked up by the CCDs  21  of the camera  20  are outputted through a controller  22  to the electronic image display unit  5 . 
         [0027]    The electronic image display unit  5  has a casing  23  that incorporates a pair of left and right display panels  24 . The display panels  24  are organic electroluminescence panels according to the present embodiment and are assembled to a substrate  25  that receives electronic image signals from the controller  22 . The casing  23  also incorporates a partition  26  that separates an inner space of the casing  23  into two. Opposite to the display panels  24 , the casing  23  has a pair of left and right eyepiece parts  27  that each include an eyepiece optical system  28 . 
         [0028]    In addition to the eyepiece parts  27 , the casing  23  incorporates objective optical systems  29 , imaging optical systems  30 , and relay optical systems R arranged between the optical systems  29  and  30 . Each objective optical system  29  receives light from the corresponding display panel  24  and each imaging optical system  30  forms a primary image F 2  from light transmitted through the corresponding objective optical system  29 . Each primary image F 2  is enlarged through the eyepiece optical system  28  and is observed by the eye of the assistant D 2 . When seeing the primary image F 2 , the eye of the assistant D 2  is placed on an eye point where light from the eyepiece optical system  28  crosses. The pair of left and right display panels  24  display the electronic images having binocular parallax, and therefore, the assistant D 2  is able to stereoscopically observe the images through the eyepiece parts  27 . 
         [0029]    A side face of the casing  23  of the electronic image display unit  5  is provided with a switch  48  to operate the servo mechanism  43  of the camera  20 . Operating the switch  48  results in moving the lenses  42  and focusing the lenses  42  with respect to the CCDs  21 . 
         [0030]    According to the present embodiment, the electronic image display unit  5  of the assistant D 2  is separately supported from the surgical microscope  4  used by the doctor D 1 . Accordingly, even if the doctor D 1  moves the surgical microscope  4 , the electronic image display unit  5  causes no movement. Namely, the doctor D 1  and assistant D 2  are allowed to freely move the surgical microscope  4  and electronic image display unit  5 , respectively, without interfering with each other. This improves operability of the devices  4  and  5  for the two persons. 
         [0031]    The electronic image display unit  5  incorporates the objective optical systems  29  and imaging optical systems  30  in the casing  23 . The primary images F 2  formed through these optical systems  29  and  30  are observed through the eyepiece optical systems  28 . Namely, the display unit  5  allows the assistant D 2  to naturally observe the primary images F 2  as if observing the images through the surgical microscope  4 . This improves an observation performance of the display unit  5  and causes no fatigue on the assistant D 2  even after a long time of observation. 
         [0032]    Accommodating the objective optical systems  29  and imaging optical systems  30  in the casing  23  of the electronic image display unit  5  improves an optical performance of the display unit  5 . Depending on the resolution and response speed of the display panels  24 , the display unit  5  is able to provide finer electronic images. The display panels  24  made of organic electroluminescence panels are superior to liquid crystal panels in response speed and contrast and such superior characteristics can fully be utilized when images on the display panels  24  are observed through the objective optical systems  29 , imaging optical systems  30 , and eyepiece parts  27 . 
         [0033]    According to the present embodiment, the camera  20  is provided with the focusing mechanism that operates separately. When the doctor D 1  adjusts the surgical microscope  4  to a focal point of his or her eye by vertically moving the surgical microscope  4  instead of controlling the internal optical system of the surgical microscope  4 , the camera  20  causes an out-of-focus state. In this case, the assistant D 2  operates the focusing mechanism to focus the lenses  42  with respect to the CCDs  21  in the camera  20  so that the electronic image display unit  5  may provide clear electronic images. 
         [0034]    This focusing operation of the camera  20  is achievable with the switch  48  arranged on a side face of the electronic image display unit  5 , and therefore, the assistant D 2  is able to easily and correctly conduct the focusing operation while observing the images provided by the display unit  5 . 
         [0035]    According to the first embodiment, the rotary plate  44  is arranged for the CCDs  21 . The rotary plate  44  is turnable to use the filters  46  that transmit light of a predetermined wavelength band to form images on the CCDs  21 . In this case, the images from the CCDs  21  allow a fluorescence observation. 
       Second Embodiment 
       [0036]    A surgical microscope system according to the second embodiment of the present invention will be explained with reference to  FIGS. 10 to 12 . The second embodiment is similar to the first embodiment, and therefore, like elements are represented with like reference marks in  FIGS. 10 to 12  to omit overlapping explanations. 
         [0037]    The surgical microscope system according to the second embodiment employs a surgical microscope  40 . In the surgical microscope  40 , main optical paths A are totally upwardly reflected by prisms  31  and are bent toward eyepiece parts  14 . Unlike the first embodiment, the second embodiment creates no sub-optical paths that run through the inside of the surgical microscope  40 . 
         [0038]    Instead, the second embodiment arranges beam splitters  32  in the main optical paths A in front of imaging optical systems  13 . Each beam splitter  32  branches the corresponding main optical path A at a right angle into a sub-optical path C. The sub-optical path C goes outside from a light outlet  33  arranged on the right (left) side of the surgical microscope  40 . According to the second embodiment, only the light outlet  33  on the right side is used and the light outlet  33  on the left side is closed. The light outlet  33  on the right side is connected to a camera  34 . 
         [0039]    The camera  34  incorporates a light dividing unit that includes a slit plate  35 , a pair of left and right parallelogram prisms  36 , and the like. 
         [0040]    The slit plate  35  has a pair of left and right holes  38  to divide the sub-optical path C branched by the beam splitter  32  of the surgical microscope  40  into two parallel beams L that are guided to CCDs  39 . 
         [0041]    Similar to the first embodiment, the second embodiment arranges, in front of the CCDs  39 , lenses  41  and  42 , a servo mechanism  43 , and a rotary plate  44 . The rotary plate  44  has filters  46 . The servo mechanism  43  drives and moves the lenses  42 . The two parallel beams L are transmitted through the rotary plate  44  and lenses  42  and  41  and are guided to the CCDs  39 , respectively. The CCDs  39  form electronic images from the beams L and the electronic images are outputted through a controller to an electronic image display unit  5 . 
         [0042]    In this way, the second embodiment branches one of the main optical paths A of the surgical microscope  40  into the sub-optical path C and divides the sub-optical path C into the two parallel beams L. Accordingly, the parallel beams L involve a slight parallax as depicted by d. Due to this parallax, the electronic image display unit  5  provides pseudo three-dimensional images instead of simple two-dimensional images. 
         [0043]    Although the first and second embodiments support the electronic image display unit  5  on the right side of the surgical microscope  4  ( 40 ), the display unit  5  may be placed at any position with respect to the surgical microscope  4  ( 40 ). For example, the display unit  5  may be arranged on the left side of the surgical microscope  4  ( 40 ), or at a position opposite to the doctor D 1 . 
         [0044]    The electronic image display unit  5  is usable not only for the assistant D 2  but also for nurses or interns for their study by installing it in a room other than the operating room. 
         [0045]    The display panels  24  of the electronic image display unit  5  are not limited to the organic electroluminescence display panels. They may be transmissive liquid crystal display panels, reflective liquid crystal display panels, or any other display panels. 
         [0046]    This application claims benefit of priority under 35USC §119 to Japanese Patent Application No. 2013-015347, filed on Jan. 30, 2013, the entire contents of which are incorporated by reference herein.