Internal observation device for object having light scattering properties, internal body observation device, endoscope for internal observation and internal observation method

Abstract

There is provided an inside observation apparatus of an endoscope and the like which can perform an inside observation for irradiating an illumination light to a minute area of a surface of an object (for example, a living tissue) having a light scattering property and detecting a back-scattered light of the illumination light, can increase a detected light amount by a simply and low cost configuration by making an area of a detection region larger than an illumination region, and can reduce a time necessary to detect an body (for example, a blood vessel) to be observed and detect a region deeper than a conventional region.

1 .- 17 . (canceled) 
     
     
         18 . An inside observation apparatus for observing, in an object having a light scattering property and a body to be observed which may exist in a deep portion of the object, an existence of the body from the object, comprising:
 an illumination device configured to irradiate a light including at least a wavelength having optical characteristics, which are different in the object and in the body, to the object;   a detection device configured to detect a light from a specific detection region in a back-scattered light of a illumination light irradiated by the illumination device and to obtain light intensity data;   an imaging device configured to analyze the obtained light intensity data and to configure an image;   a display device configured to display the image; and   an optical system in which an area of the specific detection region is larger than an illumination region of the illumination light on a surface of the object and which causes a back-scattered light from the detection region to be incident on a single detection element.   
     
     
         19 . The inside observation apparatus according to  claim 18 , wherein the illumination device and the detection device are disposed to prescribe a distance between the illumination region and the detection region. 
     
     
         20 . The inside observation apparatus according to  claim 19 , wherein, in the distance between the illumination region and the detection region, the illumination device and the detection device are disposed so that at least the illumination region is not included in the detection region. 
     
     
         21 . The inside observation apparatus according to  claim 19 , wherein an inter-center distance x between a position of the illumination light on the surface of the object and a position of the back-scattered light detected by the detection device on the surface of the object is prescribed to satisfy x≧2.8×z to an approximate depth z from the surface of the object at a position where the body exists. 
     
     
         22 . The inside observation apparatus according to  claim 18 , comprising:
 a plurality of illumination detection devices in which two or more of illumination positions illuminated by the illumination device and detection positions detected by the detection device are disposed on the surface of the object, respectively; and   an imaging device configured to configure an image caused to correspond to the illumination positions and the detection positions.   
     
     
         23 . The inside observation apparatus according to  claim 18 , comprising:
 a scanning device configured to scan a illumination position illuminated by the illumination device and a detection position detected by the detection device to the object; and   an imaging device configured to configure an image caused to correspond to the scan.   
     
     
         24 . The inside observation apparatus according to  claim 22 , wherein a size of the detection region is larger than an inter-center distance between adjacent detection regions and an interesting portion is made between adjacent detection regions. 
     
     
         25 . The inside observation apparatus according to  claim 18 , wherein a size of the detection region is made so that at least the illumination region is not included in the detection region. 
     
     
         26 . The inside observation apparatus according to  claim 22 , wherein the imaging device configures an image by causing the detected light intensity data to correspond to a gap in a scanning. 
     
     
         27 . The inside observation apparatus according to  claim 23 , wherein the detection device comprises an aperture for extracting only a back-scattered light from the detection region in the back-scattered light guided via the scanning device. 
     
     
         28 . The inside observation apparatus according to  claim 27 , wherein the detection device comprises an aperture, which extracts only a back-scattered light from the detection region in the back-scattered light guided via the scanning device disposed at a position conjugate with the detection region in an optical system for guiding a light to the aperture. 
     
     
         29 . The inside observation apparatus according to  claim 27 , wherein the detection device comprises a magnification adjustment optical system interposed between the scanning device and the aperture to make easy to take out only a back-scattered light from the detection region in the back-scattered light guided via the scanning device. 
     
     
         30 . The inside observation apparatus according to  claim 26 , comprising:
 a light guide optical system for guiding the illumination light and the back-scattered light to the same optical system; and a separation optical system for causing the illumination light from the illumination device to be incident on the light guide optical system and extracting only a back-scattered light from the detection region from the back-scattered light from the light guide optical system.   
     
     
         31 . The inside observation apparatus according to  claim 18 , wherein the illumination device uses a laser light source as a light source. 
     
     
         32 . The inside observation apparatus according to  claim 31 , wherein the illumination device uses an optical fiber to guide a laser light of the laser light source to a rear stage of the illumination device. 
     
     
         33 . The inside observation apparatus according to  claim 27  comprising an NA adjustment optical system for causing, when the illumination light is guided, the illumination light to be made to a parallel light in an illumination end in a light path until at least an illumination light outgoing from the illumination device is incident on an inside of an object. 
     
     
         34 . An apparatus for observing the interior of living body according to  claim 18  for observing, in a first living tissue and a second living tissue distributed in a deep portion of first living tissue, a distribution of the second living tissue from a surface of the first living tissue, comprising:
 an illumination device configured to irradiate a light including at least a wavelength having optical characteristics, which are different in the first living tissue and in the second living tissue, to the first living tissue; 
 a detection device configured to detect only a light from a detection region of the surface of the first living tissue in a back-scattered light of the illumination light irradiated by the illumination device and to obtain light intensity data; 
 an imaging device configured to analyze the obtained light intensity data and to configure an image; 
 a display device configured to display the image; and 
 an optical system in which an area of the detection region is larger than an illumination region of the illumination light on the surface of the first living tissue and which causes a back-scattered light from the detection region to be incident on a single detection element. 
 
     
     
         35 . The apparatus for observing the interior of living body according to  claim 34 , wherein an inter-center distance between a position of the illumination light of the surface of the first living tissue and a position of the back-scattered light, which is detected by the detection device, on the surface of the first living tissue is prescribed to be set to 8 mm or more. 
     
     
         36 . The apparatus for observing the interior of living body according to  claim 35 , configured to satisfy the following numerical expression when an area of the detection region is shown by S, a band width of the illumination light is shown by BWL, a detected light density in the detection region is shown by P, a conversion coefficient for converting the detected light to light intensity data is shown by G, a noise floor of the detection device is shown by N, an exposure time in the detection is shown by t, and a change rate of the light intensity data depending on the presence or absence of the second living tissue is shown by r. 
       
         
           
             
               S 
               ≥ 
               
                 N 
                 
                   
                     ( 
                     
                       1 
                       - 
                       r 
                     
                     ) 
                   
                   · 
                   P 
                   · 
                   G 
                   · 
                   BWL 
                   · 
                   t 
                 
               
             
           
         
       
     
     
         37 . The apparatus for observing the interior of living body according to  claim 34 , wherein when the size of the detection region in a direction is shown by D and a size of the second living tissue desired to be found is shown by W, the size of the detection region is determined to satisfy D≦W. 
     
     
         38 . The apparatus for observing the interior of living body according to  claim 34 , wherein the second living tissue contains hemoglobin, the first living tissue is a living tissue other than a blood vessel, and the illumination light is a light including a wavelength of at least 400 to 600 nm, 800 to 1000 nm, or 1350 to 1550 nm. 
     
     
         39 . The apparatus for observing the interior of living body according to  claim 34 , wherein the second living tissue is a blood vessel, the first living tissue is a living tissue other than a blood vessel, and the illumination light is a light including a wavelength of at least 900 to 1000 nm. 
     
     
         40 . A medical endoscope comprising a living body inside observation function according to  claim 18 . 
     
     
         41 . A hard endoscope comprising a living body inside observation function according to  claim 18 . 
     
     
         42 .- 66 . (canceled)