Abstract:
A particle analyzer is disclosed that comprises:
       a flow cell through which a specimen passes, the specimen including a plurality of particles to be captured;   an imaging device for capturing an image of a particle in the specimen passing through the flow cell;   an image processor for obtaining a first characteristic value of a first parameter relating to particle diameter, a second characteristic value of a second parameter relating to particle diameter, and a third characteristic value of a third parameter relating to particle diameter based on the particle image obtained by the imaging device; and   a controller for generating and outputting a screen on which the first, second and third characteristic values can be displayed at a time.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a particle analyzer which obtains information relating to the dimension and shape of a particle by analyzing an image of the particle, and a storage medium storing a computer program which imparts a function to display the information of the particle dimension and shape based on the particle image to a computer. 
       BACKGROUND 
       [0002]    There is a known conventional particle analyzer in which a particle suspension is poured into a sheath flow cell, and an image of a particle included in the particle suspension flowing in the sheath flow cell is captured and analyzed so that an analysis result is displayed (see U.S. Pat. No. 5,721,433 and Japanese Laid-Open Patent Publication 10-318904). The particle analyzer recited in U.S. Pat. No. 5,721,433 displays a two-dimensional scattergram based on two parameters representing particle characteristics (equivalent circle diameter and circularity). The analyzer recited in Japanese Laid-Open Patent Publication 10-318904 displays a three-dimensional scattergram based on three parameters representing particle characteristics (equivalent circle diameter, circularity, aspect ratio). The equivalent circle diameter is a parameter relating to particle diameter, and the circularity and the aspect ratio are parameters relating to particle shape. 
         [0003]    To analyze particles, useful information may be obtained from comparing at least three parameters relating to particle diameter. Two particles determined as having a substantially equal size by comparing two parameters relating to particle diameter, for example, may turn out to be very different in their sizes and shapes when a third parameter relating to particle diameter is added to the two parameters. To more accurately perform the particle analysis, therefore, it is desirable to compare at least three parameters relating to particle diameter, and it is similarly desirable to compare at least three parameters relating to particle shape for the same purpose. 
         [0004]    The particle analyzers recited in U.S. Pat. No. 5,721,433 and Japanese Laid-Open Patent Publication 10-318904, however, could not compare three or more parameters relating to particle diameter or particle shape. 
       SUMMARY 
       [0005]    The scope of the present invention is defined solely by the appended claims, and is not affected to any degree by the statements within this summary. 
         [0006]    A first particle analyzer embodying features of this invention comprises: 
         [0007]    a flow cell through which a specimen passes, the specimen including a plurality of particles to be captured; 
         [0008]    an imaging device for capturing an image of a particle in the specimen passing through the flow cell; 
         [0009]    an image processor for obtaining a first characteristic value of a first parameter relating to particle diameter, a second characteristic value of a second parameter relating to particle diameter, and a third characteristic value of a third parameter relating to particle diameter based on the particle image obtained by the imaging device; and a controller for generating and outputting a screen on which the first, second and third characteristic values can be displayed at a time. 
         [0010]    A second particle analyzer embodying features of this invention comprises: 
         [0011]    a flow cell through which a specimen passes, the specimen including a plurality of particles to be captured; 
         [0012]    an imaging device for capturing an image of a particle in the specimen passing through the flow cell; 
         [0013]    an image processor for obtaining a first characteristic value of a first parameter relating to particle shape, a second characteristic value of a second parameter relating to particle shape, and a third characteristic value of a third parameter relating to particle shape based on the particle image obtained by the imaging device; and 
         [0014]    a controller for generating and outputting a screen on which the first, second and third characteristic values can be displayed at a time. 
         [0015]    A first storage medium, embodying features of the invention, stores a computer program which imparts a function to display information of a particle by processing an image of the particle to a computer, the computer program executes steps of: 
         [0016]    obtaining first, second and third characteristic values of first, second and third parameters relating to particle diameter from the particle image; and 
         [0017]    generating and outputting a screen on which the first, second and third characteristic values can be displayed at a time. 
         [0018]    A second storage medium, embodying the features of the invention, stores a computer program which imparts a function to display information of a particle by processing an image of the particle to a computer, the computer program executes steps of: 
         [0019]    obtaining first, second and third characteristic values of first, second and third parameters relating to particle shape from the particle image; and 
         [0020]    generating and outputting a screen on which the first, second and third characteristic values can be displayed at a time. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  is an illustration of a structure of a particle analyzer according to an embodiment of the present invention; 
           [0022]      FIG. 2  is an illustration of a screen showing a record list displayed on a display unit of an information processing device according to the embodiment; 
           [0023]      FIG. 3  is an illustration of a screen showing an analysis result displayed on the display unit of the information processing device according to the embodiment; 
           [0024]      FIG. 4  is an illustration of a screen showing an analysis result displayed on the display unit of the information processing device according to the embodiment; 
           [0025]      FIG. 5  is an illustration of a screen showing a display parameter setting view displayed on the display unit of the information processing device according to the embodiment; 
           [0026]      FIG. 6A  illustrates a table representing specimens and parameter values thereof according to the embodiment; 
           [0027]      FIG. 6B  illustrates a table representing specimens and parameter values thereof according to the embodiment; 
           [0028]      FIG. 6C  illustrates a table representing specimens and parameter values thereof according to the embodiment; 
           [0029]      FIG. 7A  is a radar chart according to the embodiment; 
           [0030]      FIG. 7B  is a radar chart according to the embodiment; 
           [0031]      FIG. 8A  is a radar chart according to the embodiment; 
           [0032]      FIG. 8B  is a radar chart according to the embodiment; 
           [0033]      FIG. 9A  is a radar chart according to the embodiment; 
           [0034]      FIG. 9B  is a radar chart according to the embodiment; 
           [0035]      FIG. 9C  is a radar chart according to the embodiment; 
           [0036]      FIG. 10A  is a radar chart according to the embodiment; 
           [0037]      FIG. 10B  is a radar chart according to the embodiment; 
           [0038]      FIG. 10C  is a radar chart according to the embodiment; 
           [0039]      FIG. 11A  is a radar chart according to the embodiment; 
           [0040]      FIG. 11B  is a radar chart according to the embodiment; 
           [0041]      FIG. 11C  is a radar chart according to the embodiment; 
           [0042]      FIG. 11D  is a radar chart according to the embodiment; 
           [0043]      FIG. 12  is an illustration of a screen showing a particle image list displayed on the display unit of the information processing device according to the embodiment; 
           [0044]      FIG. 13  is an illustration of a screen showing a display screen for individual particle displayed on the display unit of the information processing device according to the embodiment; 
           [0045]      FIG. 14A  illustrates a table representing particles and parameter values thereof according to the embodiment; 
           [0046]      FIG. 14B  illustrates a table representing particles and parameter values thereof according to the embodiment; 
           [0047]      FIG. 15A  is a radar chart according to the embodiment; 
           [0048]      FIG. 15B  is a radar chart according to the embodiment; 
           [0049]      FIG. 15C  is a radar chart according to the embodiment; 
           [0050]      FIG. 16A  is a radar chart according to the embodiment; 
           [0051]      FIG. 16B  is a radar chart according to the embodiment; 
           [0052]      FIG. 16C  is a radar chart according to the embodiment; 
           [0053]      FIG. 17A  is a radar chart according to the embodiment; 
           [0054]      FIG. 17B  is a radar chart according to the embodiment; 
           [0055]      FIG. 17C  is a radar chart according to the embodiment; 
           [0056]      FIG. 18A  is a radar chart according to the embodiment; 
           [0057]      FIG. 18B  is a radar chart according to the embodiment; 
           [0058]      FIG. 18C  is a radar chart according to the embodiment; 
           [0059]      FIG. 19A  is a radar chart according to the embodiment; 
           [0060]      FIG. 19B  is a radar chart according to the embodiment; 
           [0061]      FIG. 19C  is a radar chart according to the embodiment; 
           [0062]      FIG. 20  is a block diagram illustrating a structure of the information processing device according to the embodiment; 
           [0063]      FIG. 21A  is a flow chart illustrating steps of a particle imaging process according to the embodiment; 
           [0064]      FIG. 21B  is a flow chart illustrating steps of an analysis result  1  display process according to the embodiment; 
           [0065]      FIG. 22A  is a flow chart illustrating steps of an analysis result  2  display process according to the embodiment; 
           [0066]      FIG. 22B  is a flow chart illustrating steps of a analysis and display process for individual particle according to the embodiment; 
           [0067]      FIG. 23A  illustrates a modified example of the radar chart according to the embodiment; and 
           [0068]      FIG. 23B  illustrates a modified example of the radar chart according to the embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0069]    The description of an embodiment given below will clearly articulate the effect and significance of the present invention. The embodiment described below, however, only suggests an example of embodying the present invention, and the present invention is not necessarily limited thereto. 
         [0070]    Hereinafter, a particle analyzer according to an embodiment of the present invention is described referring to the accompanied drawings. 
         [0071]      FIG. 1  is an illustration of a structure of a particle analyzer according to an embodiment of the present invention. The particle analyzer has a measurement device  1  and an information processing device  2 . The measurement device  1  pours a specimen into a flow cell and captures an image of a particle in the specimen flowing in the flow cell. The information processing device  2  analyzes the captured particle image and displays an analysis result thereby obtained. 
         [0072]    First, the specimen is suctioned through a suctioning pipette  11  by a suctioning device such as a diaphragm pump (not illustrated in the drawing) and passes through a sample filter  12  to be drawn into a specimen charging line  13  provided at an upper section of a flow cell  15 . The sample filter  12  removes coarse particles and dust included in the specimen as the specimen passes therethrough, thereby eliminating the risk of blocking the flow cell  15  having a narrow flow path. Another effect exerted by the sample filter  12  is to crumble coarse agglomerates. 
         [0073]    A sheath syringe  14  is turned on, so that the specimen sucked in the specimen charging line  13  is guided into the flow cell  15 . The specimen guided into the flow cell  15  extruded through a lower end of a sample nozzle  15   a . At the same time, a sheath liquid is poured into the flow cell  15  from a sheath liquid bottle  16  through a sheath liquid chamber  17 . The specimen in the flow cell  15  is surrounded by the sheath liquid and then formed into a flat specimen flow. 
         [0074]    The specimen flow thus flattened is irradiated with a pulsed light from a strobo light  18  at time intervals of 1/60 second, and a still image of a particle included in the specimen is captured every approximately 2μ second by a camera  20  via an object lens  19 . An image signal outputted from the camera  20  is inputted to the information processing device  2 . 
         [0075]    The information processing device  2  obtains an image of each particle based on the inputted image signal in parallel with reception of the image signal. The information processing device  2  obtains parameter values representing particle characteristics based on each of the obtained particle images, and displays an analysis result of the specimen on a display unit. The structure of the information processing device  2  will be described later referring to  FIG. 20 . 
         [0076]    A description is given below to the parameters representing the particle characteristics obtained by the information processing device  2  based on the particle image. 
         [0077]    The parameters representing the particle characteristics obtained by the information processing device  2  are classified into parameters in which a particle diameter is quantitatively determined and parameters in which a particle shape is quantitatively determined. The parameters in which a particle diameter is quantitatively determined include: equivalent circle diameter; maximum length; vertical length of maximum length; long-axis diameter; short-axis diameter; Feret diameter (horizontal); Feret diameter (vertical); perimeter equivalent circle diameter; particle perimeter; particle area; envelope perimeter; envelope area; and area equivalent circle diameter. The parameters in which a particle shape is quantitatively determined includes: circularity; aspect ratio; aspect ratio of horizontally circumscribed rectangle; average luminance value, luminance dispersion value; degree of envelope (perimeter); degree of envelope (area); and circularity (area). The parameters are described in detail below. 
         [0000]    
       
         
               
             
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 &lt;Particle diameter&gt; 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Equivalent circle 
                 Diameter of circle having circumference 
               
               
                   
                 diameter 
                 equal to particle perimeter 
               
               
                   
                 (area equivalent 
                 (diameter of circle having area equal to 
               
               
                   
                 circle diameter): 
                 particle area) 
               
               
                   
                 Maximum length 
                 Maximum length between two points on 
               
               
                   
                   
                 contour of particle image 
               
               
                   
                 Vertical length of 
                 When particle is sandwiched between two 
               
               
                   
                 maximum length 
                 straight lines in parallel with straight 
               
               
                   
                   
                 line which connects two points 
               
               
                   
                   
                 representing maximum length, shortest 
               
               
                   
                   
                 length which vertically connects the two 
               
               
                   
                   
                 straight lines 
               
               
                   
                 Long-axis diameter 
                 Length of long axis when particle is 
               
               
                   
                   
                 sandwiched between two pairs of parallel 
               
               
                   
                   
                 lines 
               
               
                   
                 Short-axis diameter 
                 Length of short axis when particle is 
               
               
                   
                   
                 sandwiched between two pairs of parallel 
               
               
                   
                   
                 lines 
               
               
                   
                 Feret diameter 
                 Horizontal tangent diameter defined by 
               
               
                   
                 (horizontal) 
                 distance between two pairs of parallel 
               
               
                   
                   
                 lines sandwiching particle 
               
               
                   
                 Feret diameter 
                 Vertical tangent diameter defined by 
               
               
                   
                 (vertical) 
                 distance between two pairs of parallel 
               
               
                   
                   
                 lines sandwiching particle 
               
               
                   
                 Perimeter equivalent 
                 Diameter of circle equal to particle 
               
               
                   
                 circle diameter 
                 perimeter 
               
               
                   
                 Particle perimeter 
                 Peripheral length of particle 
               
               
                   
                 Particle area 
                 Area of particle 
               
               
                   
                 Envelope perimeter 
                 Perimeter of shape connecting 
               
               
                   
                   
                 protruding portions of particle 
               
               
                   
                 Envelope area 
                 Area of shape connecting protruding 
               
               
                   
                   
                 portions of particle 
               
               
                   
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 &lt;Particle shape&gt; 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Circularity 
                 Ratio between particle perimeter and 
               
               
                   
                 perimeter of circle corresponding to 
               
               
                   
                 projected area of particle image 
               
               
                 Aspect ratio 
                 Ratio between long-axis diameter and 
               
               
                   
                 short-axis diameter 
               
               
                 Aspect ratio of 
                 When particle is surrounded by 
               
               
                 horizontally 
                 horizontally circumscribed rectangle, 
               
               
                 circumscribed 
                 aspect ratio of the rectangle 
               
               
                 rectangle 
               
               
                 Average luminance 
                 Average of pixel luminance values in 
               
               
                 value 
                 particle region 
               
               
                 Luminance dispersion 
                 Standard deviation of pixel luminance 
               
               
                 value 
                 values in particle region 
               
               
                 Degree of envelope 
                 Ratio between envelope perimeter and 
               
               
                 (perimeter) 
                 particle perimeter 
               
               
                 Degree of envelope 
                 Ratio between particle area and envelope 
               
               
                 (area) 
                 area 
               
               
                 Circularity (area) 
                 ratio between projected area of particle 
               
               
                   
                 image and area of circle equal to 
               
               
                   
                 particle perimeter 
               
               
                   
               
             
          
         
       
     
         [0078]      FIG. 2  is an illustration of a screen showing a record list displayed on the display unit of the information processing device  2 . The illustrated screen is displayed when a record list tab  110  is pressed. 
         [0079]    As illustrated in the drawing, the display unit includes a menu  100 , a record list  111 , and a select-cancel button  112 . The menu  100  includes a record list tab  110 , analysis result tabs  120  and  130 , and a particle image list tab  140 . When these tabs are pressed, screens corresponding to the pressed tabs are displayed. 
         [0080]    The record list  111  displays thereon records of specimens measured by the measurement device  1 . The record is a measurement result obtained by a measuring operation carried out under given measurement conditions. For example, when a user commands to end the measuring operation already started and the measuring operation is ended, the measurement result obtained during the measuring operation is created as one record. In the event that the analyzer is set to end the measuring operation as soon as the number of measured particles after the measurement started reaches a given number, the measurement result obtained during the measuring operation is created as one record. 
         [0081]    As illustrated in the drawing, record items include: record number; measurement date and time; specimen number; statistical values (for example, average, SD, CV) of the parameters (equivalent circle diameter, circularity). The record number is a specific number used to identify each record. The measurement date and time is a date and time when the measurement relevant to the record ended. The specimen number is a number used to identify each specimen. The specimen number is associated with the specimen name. 
         [0082]    The statistical values (for example, average, SD, CV) are obtained through statistics of parameter values of whole particles in one record. For example, average in the section of equivalent circle diameter in a record shows an average value of equivalent circle diameter values of all of particles measured to obtain the record. SD shows a standard deviation of the parameter values, and CV shows a coefficient of variation (degree of variability) calculated from the average and SD. 
         [0083]    When a cell in the record list  111  is pressed, a record including the cell is highlighted to be selectable. When the select-cancel button  112  is pressed, selection of any record on the table is cancelled. On the record list  111 , a plurality of records can be selected. 
         [0084]    At the right and left ends of the record list  111 , scroll bars respectively used to shift its display region side to side and up and down are provided. All of the records can be viewed when the up-down scroll bar is scrolled, and all of the record items can be viewed when the side-to-side scroll bar is scrolled. 
         [0085]      FIG. 3  is an illustration of a screen showing an analysis result  1  displayed on the display unit of the information processing device  2 . The illustrated screen is displayed when the analysis result tab  120  is pressed in a state where one record is selected on the record list  111  of  FIG. 2 . 
         [0086]    As illustrated in the drawing, the display unit includes, in addition to a menu  100  similar to that of  FIG. 2 , a record information list  121 , a particle diameter histogram  122 , a particle diameter parameter selection box  123 , a particle shape histogram  124 , a particle shape parameter selection box  125 , and a scattergram  126 . 
         [0087]    The record information list  121  displays information associated with one record selected on the record list  111  illustrated in  FIG. 2 . 
         [0088]    The particle diameter histogram  122  displays, in the form of histogram, distribution of the particle diameter parameters of different particles measured in the record displayed on the record information list  121 . The particle diameter parameter displayed on the particle diameter histogram  122  is selected from a list of selectable particle diameter parameters when the particle diameter parameter selection box  123  is pressed. A lateral axis of the particle diameter histogram  122  is set in a range corresponding to the particle diameter parameter currently displayed, and right and left sides of a longitudinal axis respectively represent accumulation and frequency. 
         [0089]    The particle shape histogram  124  displays, in the form of histogram, distribution of the particle shape parameters of different particles measured to in the record displayed on the record information list  121 . The particle shape parameter displayed on the particle shape histogram  124  is selected from a list of selectable particle shape parameters when the particle shape parameter selection box  125  is pressed. A longitudinal axis of the particle shape histogram  123  is set in a range corresponding to the particle shape parameter currently displayed, and upper and lower sides of a lateral axis respectively represent accumulation and frequency. 
         [0090]    When the particle diameter histogram  122  and the particle shape histogram  124  are displayed, a user can know values of the particle diameter parameters and particle shape parameters in different particles measured in the record displayed on the record information list  121 . 
         [0091]    The scattergram  126  is a graph two-dimensionally or three-dimensionally expressing the combined contents of the particle diameter histogram  122  and the particle shape histogram  124 . A lateral axis and a longitudinal axis of the scattergram  126  are set in the same manner as the lateral axis of the particle diameter histogram  122  and the longitudinal axis of the particle shape histogram  124 . 
         [0092]    When the scattergram  126  is displayed, a user can know distribution of values of the particle diameter parameters and particle shape parameters in different particles measured in the record displayed on the record information list  121 . 
         [0093]      FIG. 4  is an illustration of a screen showing an analysis result  2  displayed on the display unit of the information processing device  2 . The illustrated screen is displayed when the analysis result tab  130  is pressed in a state where at least one record is selected on the record list  111  illustrated in  FIG. 2 . 
         [0094]    As illustrated in the drawing, the display unit includes, in addition to a menu  100  similar to that of  FIG. 2 , a parameter value list  131 , a chart  132 , and a display parameter setting button  133 . 
         [0095]    The parameter value list  131  displays statistical values of the parameters associated with the specimen in at least one record selected on the record list  111  illustrated in  FIG. 2 . Items laterally shown display names of specimens corresponding to the records selected on the record list  111 , and items longitudinally shown displays the parameters. The parameters are defaulted in six items illustrated in the same drawing (equivalent circle diameter, long-axis diameter, short-axis diameter, circularity, aspect ratio, degree of envelope (area). As described later, the parameters can be changed by pressing the display parameter setting button  133  and then displaying a display parameter setting screen. At the right and left ends of the parameter value list  131 , scroll bars respectively used to shift its display region side to side and up and down are provided. In the case where contents to be displayed cannot be displayed within the display region of the parameter value list  131 , these scroll bars can be used to display the specimen names and parameters in all of the records. 
         [0096]    The chart  132  displays a radar chart based on the parameter values displayed on the parameter value list  131 .  FIG. 4  illustrates a radar chart showing on one screen three specimens displayed on the parameter value list  131 , and statistical values of three parameters relating to particle diameter and statistical values of three parameters relating to particle shape based on statistical values of six parameters of these specimens. When the chart  132  is thus displayed, a plurality of parameters of a plurality of specimens can be compared at a time. 
         [0097]    The display parameter setting button  133  is used to set the parameters to be displayed on the parameter value list  131  and the chart  132 . When the display parameter setting button  133  is pressed, a display parameter setting screen illustrated in  FIG. 5  is displayed. 
         [0098]    Referring to  FIG. 5 , a display parameter setting screen  200  includes setting regions  201  to  205 , and an OK button  206 . 
         [0099]    On the setting region  201 , the particle diameter parameters to be displayed on the parameter value list  131  and the chart  132  illustrated in  FIG. 4  are selected. When the particle diameter parameters displayed on the setting region  201  are pressed, relevant check boxes are checked as illustrated in the drawing, and it is known that the parameters with the checked boxes are selected. On the setting region  202 , the particle shape parameters displayed on the parameter value list  131  and the chart  132  illustrated in  FIG. 4  are selected. When the particle shape parameters displayed on the setting region  202  are pressed, relevant check boxes are checked as illustrated in the drawing, and it is known that the parameters with the checked boxes are selected. 
         [0100]    On the setting region  203 , types of the parameter statistical values displayed on the parameter value list  131  and the chart  132  illustrated in  FIG. 4  are selected. The selectable types of the statistical values include the statistical values of parameters illustrated in  FIG. 2  (for example, average, SD, and CV). 
         [0101]    On the setting region  204 , a reference parameter for normalizing the parameter values displayed on the parameter value list  131  and the chart  132  illustrated in  FIG. 4  is set. For example, when the long-axis diameter is selected as the reference parameter for normalization as illustrated in the drawing, the other parameter values are set so that the long-axis diameter shows the value of 1. The values thus set are displayed in  FIG. 4 . The average luminance value is normalized in the range of 0 to 1.0. In the case where the average luminance value is included in a range of specific thresholds previously set, the average luminance value is normalized in the range of 0-1.0 depending on the threshold value. The average luminance value exceeding the threshold value is always normalized to “1.0”. In the event that the reference parameter for normalization is not set, actually measured values are used as the statistical values. 
         [0102]    On the setting region  205 , a display range of axes displayed on the chart  132  illustrated in  FIG. 4  is set. When the display range is set to 0-1 as illustrated in the drawing, for example, the center of the axes expresses 0, and the outermost end thereof expresses 1 as illustrated in  FIG. 4 . 
         [0103]    When the OK button  206  is pressed, the parameters set in the display parameter setting screen  200  are reflected on the screen of the analysis result  2  illustrated in  FIG. 4 . Then, the parameter value list  131  and the chart  132  illustrated in  FIG. 4  are accordingly updated. 
         [0104]    Various examples of the radar chart displayed on the chart  132  of  FIG. 4  are illustrated in  FIGS. 7 to 11 . 
         [0105]      FIG. 6  illustrates names of specimens of the records referenced when the radar chart is created, and parameter values relevant to the specimen names of the records.  FIG. 6A  illustrates the parameter values obtained by normalizing average values of actually measured values in different particles, in which the parameter values are normalized based on the long-axis diameter. As described earlier, the average luminance value is normalized in the range of 0 to 1.0. The parameter values of  FIG. 6B  represent CV (degree of variability). The parameter values of  FIG. 6C  represent the average values of actually measured values in different particles. To simplify the illustration, the Feret diameter illustrated in  FIG. 6C  is one of average Feret diameter (horizontal) and average Feret diameter (vertical) larger than the other. 
         [0106]      FIGS. 7A and 7B  are radar charts when three specimens and six parameters are selected from the specimens and the parameters illustrated in  FIG. 6A . The six parameters are defaulted. “LATEX” generally called standard sample particles is a specimen containing particles having nearly spherical shapes. 
         [0107]    As illustrated in  FIG. 7A , the radar charts of “LATEX 4204A”, “Tonar”, and “Almina” have shapes closer to regular hexagon in the mentioned order. It is known from the illustration that “LATEX 4204A”, “Tonar”, and “Almina” contain particles having shapes closer to spherical shape in the mentioned order. 
         [0108]    As illustrated in  FIG. 7B , the radar charts of “LATEX 4203A”, “LATEX 4204A”, and “LATEX 4202A” have shapes closer to regular hexagon in the mentioned order. It is known from the illustration that “LATEX 4203A”, “LATEX 4204A”, and “LATEX 4202A”, contain particles having shapes closer to spherical shape in the mentioned order. The display range of the axes in  FIG. 7B  is set to 0.6 to 1. The display region is thus set based on display range of the setting region  205  on the display parameter setting screen illustrated in  FIG. 5 . 
         [0109]      FIGS. 8A and 8B  are radar charts when three specimens and six parameters are selected from  FIG. 6B . The six parameters are defaulted. 
         [0110]    According to the radar charts illustrated in  FIG. 8A , it is known that “LATEX 4204A”, “LATEX 4203A”, and “LATEX 4202A” have smaller degrees of variability in the mentioned order. According to the radar charts of  FIG. 8B , “LATEX 4204A”, “Tonar”, and “Almina” have smaller degrees of variability in the mentioned order. It is also known that the degree of variability is largely different from one specimen to another. 
         [0111]      FIGS. 9A-9C  are radar charts when three specimens and five, three, and four parameters are selected from  FIG. 6C . The default of the parameters is changed using the display parameter setting screen illustrated in  FIG. 5 . Likewise, it is determined whether or not the radar charts of  FIGS. 9A to 9C  have shapes close to regular pentagon, regular triangle, or square to know whether or not the particles of the specimens are nearly circular. Because the parameter values of these radar charts are the average values of actually measured values, it can be confirmed whether or not the different specimens have different values in a particular parameter. 
         [0112]    All of the parameters displayed on the radar charts of  FIGS. 9A to 9C  are the particle diameter parameters. When the particle diameter parameters alone are selected, it is desirable to include three of the particle diameter parameters, equivalent circle diameter, long-axis diameter and short-axis diameter. Referring to these three parameters, an outer shape of the particle, as well as its dimension, can be easily grasped. 
         [0113]      FIGS. 10A to 10C  are radar charts when three specimens and three parameters are selected from  FIG. 6A . The state of the parameters is already changed from their default state using the display parameter setting screen illustrated in  FIG. 5 . Likewise, it is determined whether or not the radar charts have shapes close to regular triangle to know whether or not the particles of the specimens are nearly circular. 
         [0114]      FIG. 10B  illustrates the radar chart in which the parameter display range of  FIG. 10A  is set to 0.5 to 1.  FIG. 10B , therefore, makes it easier to grasp the shape of the radar chart rather than  FIG. 10A . In  FIG. 10C , it is difficult to differentiate the shapes of the radar charts of three specimens, the parameter display range is set to 0.8 to 1. This helps to readily know that the particles of “LATEX 4203A” are more spherical than any other specimens. 
         [0115]    All of the parameters displayed on the radar charts of  FIGS. 10A to 10C  are the particle shape parameters. When the particle shape parameters alone are selected, it is desirable to include three of the particle shape parameters, which are circularity, aspect ratio, and degree of envelope. Referring to these three parameters, the particle shape can be accurately grasped. 
         [0116]      FIGS. 11A to 11D  are radar charts when three specimens and 4 to 5 parameters are selected from  FIG. 6A . The state of the parameters is already changed from their default state using the display parameter setting screen illustrated in  FIG. 5 . Likewise, it is determined whether or not the radar charts have shapes close to regular pentagon or square to know whether or not the particles of the specimens are nearly spherical. 
         [0117]      FIG. 11B  illustrates the radar chart in which the parameter display range of  FIG. 11A  is set to 0.5 to 1.  FIG. 11D  illustrates the radar chart in which the parameter display range of  FIG. 11C  is set to 0.5 to 1. Therefore,  FIG. 11B  makes it easier to grasp the shape of the radar chart rather than  FIG. 11A , and  FIG. 11D  makes it easier to grasp the shape of the radar chart rather than  FIG. 11C . 
         [0118]      FIG. 12  is an illustration of a screen showing a particle image list displayed on the display unit of the information processing device  2 . The illustrated screen is displayed when the particle image list tab  140  is pressed in a state where at least two records are selected on the record list  111  illustrated in  FIG. 2 . 
         [0119]    As illustrated in the drawing, the display unit includes, in addition to a menu  100  similar to that of  FIG. 2 , record information lists  141  and  143 , and particle image lists  142  and  144 . 
         [0120]    The record information lists  141  and  143  display information of the records selected on the record list  111  illustrated in  FIG. 2 . 
         [0121]    The particle image lists  142  and  144  respectively display the images of all of particles measured in the records displayed on the record lists  141  and  143 . At the right ends of the particle image lists  142  and  144 , scroll bars respectively used to shift their display regions up and down are provided. Accordingly, all of the particle images on the particle image lists  142  and  144  can be viewed. 
         [0122]    In the example illustrated in  FIG. 12 , two records are displayed. When one record is selected on the record list  111  illustrated in  FIG. 2 , the record contents are displayed on the record information list  141  and the particle image list  142  alone. In the event that at least three records are selected on the record list  111  illustrated in  FIG. 2 , the record information lists and the particle image lists are suitably arranged on the screen depending on the number of selected records. In such a case, the display regions of the record information lists and the particle image lists that correspondent to the respective records are suitably adjusted on the screen. 
         [0123]    When the particle images of the particle image lists  142  and  144  are selected, a particle selection range  145  is set. In response to an operation to display a submenu on the particle selection range  145 , a selection display menu  146  is displayed. In the drawing, the particle selection range  145  is set for the particle images continuously displayed, however, can also be set for an arbitrary number of any particle images displayed on the particle image lists  142  and  144 . 
         [0124]    The selection display menu  146  is provided with an “analysis and display for individual particle” window. When the “analysis and display for individual particle” window is pressed, a display screen for individual particle illustrated in  FIG. 13  is displayed. 
         [0125]    Referring to  FIG. 13 , a display screen for individual particle  150  includes a parameter value list  151 , a particle image list  152 , a chart  153 , and a display parameter setting button  154 . 
         [0126]    The parameter value list  151  displays information of particles selected by the particle selection range  145  on the particle image list illustrated in  FIG. 12 . Items laterally shown displays names of specimens corresponding to the particles selected by the particle selection range  145 , and items longitudinally shown displays the parameters of the particles. The six parameters are defaulted. The parameters can be changed by pressing the display parameter setting button  154  and then displaying parameter setting screen, which will be described later. 
         [0127]    The particle image list  152  displays the images of the particles displayed on the parameter value list  151 . Along with the particle images, particles names are displayed, which are the specimen names with serial numbers appended thereto. 
         [0128]    The chart  153  displays a radar chart based on the parameter values displayed on the parameter value list  151 . The illustration of  FIG. 13  displays a radar chart showing on one screen two particles displayed on the parameter value list  151 , and three parameter values relating to particle diameter and three parameter values relating to particle shape based on six parameters of these particles. When the chart  153  is thus displayed, a plurality of parameters of a plurality of particles can be compared at a time. 
         [0129]    The display parameter setting button  154  is used to set the parameters to be displayed on the parameter value list  151  and the chart  153 . When the display parameter setting button  154  is pressed, a setting screen similar to the display parameter setting screen  200  illustrated in  FIG. 5  is displayed. In the display parameter setting screen thus displayed, a region corresponding to the setting region  203  is omitted. 
         [0130]    When the parameters are changed on the setting screen, any changes made then are reflected on the display screen for individual particle  150  illustrated in  FIG. 13 , and the display contents of the parameter value list  151  and the chart  153  illustrated in  FIG. 13  are updated. 
         [0131]    Various examples of the radar chart displayed on the chart  151  of  FIG. 13  are illustrated in  FIGS. 15 to 19 . 
         [0132]      FIG. 14  illustrate names of particles in the records referenced when the radar chart is created, and the parameter values of the particles.  FIG. 14A  illustrates the parameter values obtained by normalizing actually measured values of different particles, in which the values are normalized based on the long-axis diameter. As described earlier, the average luminance value is normalized in the range of 0 to 1.0. The parameter values illustrated in  FIG. 14B  represent actually measured values of the respective particles. To simplify the illustration, the Feret diameter illustrated in  FIG. 14C  is one of Feret diameter (horizontal) and Feret diameter (vertical) larger than the other. 
         [0133]      FIG. 15A  is a radar chart when two particles of one specimen and six parameters thereof are selected from  FIG. 14A . The six parameters are defaulted. By determining whether or not the radar chart of  FIG. 15A  has a shape close to regular hexagon, it is known whether or not the particle image is nearly circular. 
         [0134]      FIG. 15B  is a radar chart when two particles of one specimen and three parameters thereof are selected from  FIG. 14B . The state of the parameters is already changed from their default state using the display parameter setting screen. Likewise, it is determined whether or not the radar chart of  FIG. 15B  has a shape close to regular triangle to know whether or not the particle image is nearly circular. The display range of the axes in  FIG. 15B  is set to 10 to 20. 
         [0135]      FIG. 15C  is a radar chart when two particles of one specimen and three parameters thereof are selected from  FIG. 14A . The state of the parameters is already changed from their default state using the display parameter setting screen. Likewise, it is determined whether or not the radar chart of  FIG. 15C  has a shape close to regular pentagon to know whether or not the particle image is nearly circular. 
         [0136]    In  FIGS. 16 and 17 , the shapes of the radar charts are determined to know whether or not the particle images are nearly circular in a manner similar to  FIG. 15 .  FIGS. 18 and 19  are radar charts when two particles of different specimens are selected. Likewise, the shapes of the radar charts are determined to know whether or not the particle images are nearly circular. 
         [0137]      FIG. 20  is a block diagram illustrating the structure of the information processing device  2 . 
         [0138]    The information processing device  2  is made of a personal computer, and includes a main body  300 , an input unit  310 , and a display unit  320 . The main body  300  has a CPU  301 , a ROM  302 , a RAM  303 , a hard disc  304 , a read out device  305 , an input/output interface  306 , an image output interface  307 , and a communication interface  308 . 
         [0139]    The CPU  301  runs a computer program stored in the ROM  302  and a computer program loaded into the RAM  303 . The RAM  303  is used to read out the computer programs recorded on the ROM  302  and the hard disc  304 . The RAM  303  is also used as a working region of the CPU  301  when the computer programs are run. 
         [0140]    The hard disc  304  is installed with various computer programs to be run by the CPU  301  such as operating system and application program, as well as data used to run the computer programs. More specifically, the hard disc  304  is installed with a program for receiving an image signal outputted from a camera  20 , creating an image of each particle based on the received image signal, and analyzing a specimen based on the particle image, and a display program for displaying an analysis result on the display unit  320 . By installing these programs, the analyzing process and the display process illustrated in  FIGS. 2 to 19  are carried out. 
         [0141]    The read out device  305  includes a CD drive or a DVD drive. The read out device  305  can read a computer program and data recorded on an external storage such as a recording medium. Therefore, the programs executed by the information processing device  2  can be updated via the external storage, for example, recording medium. 
         [0142]    The input unit  310  including a keyboard and a mouse is connected to the input/output interface  306  so that a user can input a command to the information processing device  2  using the input unit  310 . The image output interface  307  is connected to the display unit  320  including, for example, a display screen so that a video signal based on image data is displayed on the display unit  320 . The display unit  320  displays an image based on the inputted video signal. The image signal outputted from the camera  20  can be inputted through the communication interface  308 . 
         [0143]      FIG. 21A  is a flow chart illustrating steps of the particle imaging process carried out in the information processing device  2 . 
         [0144]    When the particle image is captured by the camera  20 , the image signal outputted from the camera  20  is received by the information processing device  2  through the communication interface  308  (S 1 ). After a predetermined image processing is applied to the received image signals, the resulting image signals are separated from one another by each particle, and the particle image is generated therefrom for individual particle. The generated particle images are stored in the hard disc  304  (S 2 ). Based on the particle images, all of the parameter values relating to particle diameter and particle shape described so far are calculated (S 3 ). The calculated parameters are stored in the hard disc  304  in association with the particle image. Then, statistical values of equivalent circle diameter and circularity (average, SD, CV) are calculated based on the actually measured values of equivalent circle diameter and circularity of each particle, and then stored in the hard disc  304  (S 4 ). Then, the particle imaging process ends. 
         [0145]    When the record list screen illustrated in  FIG. 2  is thereafter displayed, record information of the specimen most recently measured is added to the list, and the statistical values obtained in S 4  (average, SD, CV) are included in the record information. 
         [0146]      FIG. 21B  is a flow chart illustrating steps of a display process of an analysis result  1 . 
         [0147]    The process is carried out when the analysis result tab  120  is pressed in a state where one record is selected on the record list  111  of  FIG. 2 . 
         [0148]    First, all of the parameter values relating to particle diameter and particle shape are obtained from the hard disc  304  for the record selected on the record list  111  of  FIG. 2  (S 11 ). An initial screen of the analysis result  1  is generated and displayed based on the obtained parameter values (S 12 ). In this description, the record information list  121  of  FIG. 3  displays the record information selected on the record list  111  of  FIG. 2 . Further, the particle diameter histogram  122 , particle shape histogram  124 , and scattergram  126  are generated based on the parameters (equivalent circle diameter, circularity) defaulted in the particle diameter parameter selection box  123  and the particle shape parameter selection box  125 , and then displayed in the corresponding regions of  FIG. 3 . 
         [0149]    When the initial screen of the analysis result  1  is thus displayed, it is determined whether or not the parameters in the particle diameter parameter selection box  123  and the particle shape parameter selection box  125  have been changed (S 13 ). When any of the parameters is changed (S 13 : YES), the particle diameter histogram  122 , particle shape histogram  124 , and scattergram  126  are generated based on the changed parameters, and then displayed in the corresponding region of  FIG. 3  (S 14 ). The process then returns to S 13  to determine again whether or not any of the parameters is changed. When any tab other than the analysis result tab  120  is selected via the menu  100  of  FIG. 3  during the determination, the display process of the analysis result  1  ends. 
         [0150]      FIG. 22A  is a flow chart illustrating steps of a display process of an analysis result  2 . 
         [0151]    The process is carried out when the analysis result tab  130  is pressed in a state where at least one record is selected on the record list  111  of  FIG. 2 . 
         [0152]    First, all of the parameter values relating to particle diameter and particle shape are obtained from the hard disc  304  for the record selected on the record list  111  of  FIG. 2  (S 21 ). An initial screen of the analysis result  1  is generated and displayed based on the obtained parameter values (S 22 ). The parameter values are obtained from the default values of the set parameters of  FIG. 5 . Then, based on the defaulted parameters and the obtained parameter values, the parameter value list  131  and the chart  132  of  FIG. 4  are displayed. An example of the initial screen of the analysis result  1  is illustrated in  FIG. 4 . 
         [0153]    When the initial screen of the analysis result  2  is thus displayed, it is determined whether or not any of the parameters (setting region  201 ,  202 ), type of statistical value (setting region  203 ), reference parameter for normalization (setting region  204 ), and display range (setting region  205 ) is changed based on the display parameter setting screen of  FIG. 5  (S 23 ). Having determined that any of the parameters, type of statistical value, reference parameter for normalization, and display range is changed (S 23 : YES), the parameter value list  131  and the chart  132  are reconfigured based on the changed contents, and then displayed on the corresponding region of  FIG. 4  (S 24 ). Then, the process returns to S 23  to determine again whether or not any of the parameters, type of statistical value, reference parameter for normalization, and display range is changed. When any tab other than the analysis result tab  130  is selected via the menu  100  of  FIG. 3  during the determination, the display process of the analysis result  2  ends. 
         [0154]      FIG. 22B  is a flow chart illustrating steps of an analysis and display process for individual particle. 
         [0155]    This process is carried out when an “analysis and display for individual particle” window on the selection display menu  146  based on the particle selection range  145  set on the particle image lists  142  and  144  of  FIG. 12  is pressed. When the particle image list screen illustrated in  FIG. 12  is displayed, all of the parameter values relating to particle diameter and particle shape for the records to be displayed on the list screen are obtained from the hard disc  304 . 
         [0156]    First, all of the parameter values relating to the diameters and shapes of particles included in the particle selection range  145  set on the particle image lists  142  and  144  of  FIG. 12  are obtained (S 31 ). Based on the obtained parameter values, an initial screen of the “analysis and display for individual particle” is generated and displayed (S 32 ). The parameter values are obtained from the default values of the set parameters of  FIG. 5 . Then, based on the defaulted parameters and the obtained parameter values, the parameter value list  151  and the chart  153  of  FIG. 4  are displayed. An example of the initial screen of the “analysis and display for individual particle” is illustrated in  FIG. 13 . 
         [0157]    When the initial screen of the “analysis and display for individual particle” is thus displayed, the display parameter setting button  154  illustrated in  FIG. 13  is pressed to determine whether or not the set parameters have been changed (S 33 ). As described earlier, when the display parameter setting button  154  is pressed, the screen in which the setting region  203  is deleted from the display parameter setting screen of  FIG. 5  is displayed so that the set parameters can be changed. When the screen is operated to change any of the parameters (setting region  201 ,  202 ), reference parameter for normalization (setting region  204 ) and display range (setting region  205 ) (S 33 : YES), the parameter value list  151  and the chart  153  are reconfigured based on the changed contents and displayed on the corresponding regions illustrated in  FIG. 13  (S 34 ). Then, the process returns to S 33  to determine again whether or not any of the parameters, reference parameter for normalization and display range is changed. When an operation to end the “analysis and display for individual particle” is done during the determination, the display process of the “analysis and display for individual particle” ends. 
         [0158]    Processes in  FIGS. 21 and 22  are carried out by the CPU  301  in accordance with the program installed in the hard disc  304  illustrated in  FIG. 20 . The analysis and display processes described referring to  FIGS. 2 to 19  are carried out based on the processes using the program. 
         [0159]    According to the present embodiment, the chart  132  of  FIG. 4  displays the radar chart where arbitrary particle diameter parameters and arbitrary particle shape parameters of one specimen can be subjected to comparison. Accordingly, characteristics of one specimen can be visually grasped based on a plurality of parameters. 
         [0160]    Because the radar charts of a plurality of specimens can be displayed as well, characteristics of the different specimens can be visually compared. 
         [0161]    According to the present embodiment, the chart  153  of  FIG. 13  displays the radar chart where arbitrary particle diameter parameters and arbitrary particle shape parameters of one particle can be subjected to comparison. Accordingly, characteristics of one particle can be visually grasped based on a plurality of parameters. 
         [0162]    Because the radar charts of a plurality of particles can be displayed as well, characteristics of the different particles can be visually compared. 
         [0163]    The embodiment of the present invention was described so far. The present invention, however, is not necessarily limited to the embodiment, and the embodiment can be variously modified. 
         [0164]    According to the present embodiment, the chart  132  of  FIG. 4  and the chart  153  of  FIG. 13  display the radar charts. As far as a plurality of parameter values can be compared in a plurality of specimens or particles, any charts other than the radar chart may be displayed. 
         [0165]      FIG. 23  illustrate charts which can be used in place of the radar charts. 
         [0166]      FIGS. 23A and 23B  are respectively a polygonal line graph and a bar graph when three specimens and six parameters are selected. When these charts are displayed, a plurality of parameters can be compared in a plurality of specimens in a manner similar to the radar charts. The charts of  FIGS. 23A and 23B  can display a plurality of parameters of a plurality of particles, in which case a plurality of parameters can be similarly compared in a plurality of particles. 
         [0167]    According to the present embodiment, the chart  153  displays the radar chart of each particle as illustrated in  FIGS. 12 and 13 . The radar chart of  FIG. 13  may be displayed based on a comparison unit in which the particle selection range including a plurality of particles in  FIG. 12  is set as the unit. 
         [0168]    More specifically, after the particle selection range including a plurality of particles is set in  FIG. 12 , particles included in the selection range are used as the comparison unit. Then, another comparison unit including different particles is set.  FIG. 13  illustrates the radar chart showing statistical values of the parameters of the particles included in the comparison units. Instead of comparing different particles, the units each including a plurality of particles can be used as the basis of comparison. The display parameter setting screen is provided with a region corresponding to the setting region  203  of  FIG. 5 , in which types of statistical values of the displayed parameters are selectable. 
         [0169]    According to the present embodiment, the statistical values of equivalent circle diameter and circularity are calculated during the measuring operation. Instead, the statistical values of these parameters may be calculated during the display of the analysis result  1  of  FIG. 3  or the analysis result  2  of  FIG. 4 , or the statistical values of all of the parameters may be calculated during the measuring operation. 
         [0170]    According to the present embodiment, equivalent circle diameter, long-axis diameter, and short-axis diameter are used as the particle diameter parameters, and circularity, aspect ratio, and degree of envelope (area) are used as the particle shape parameters on the initial screen (default) of the analysis result  2  and the initial screen (default) of the “analysis and display for individual particle”. On these initial screens, combination of any other parameters may be set, and at least four particle diameter parameters or at least four particle shape parameters may be set. However, the particle diameter parameters preferably include equivalent circle diameter, long-axis diameter, and short-axis diameter, and the particle shape parameters preferably include circularity, aspect ratio, and degree of envelope (perimeter or area). 
         [0171]    The selectable parameters are not necessarily limited to the parameters illustrated in  FIG. 5 , and other parameters may be included as the particle diameter parameters and particle shape parameters. 
         [0172]    The embodiment of the present invention can be variously modified within the scope of the technical idea disclosed in the appended claims.