Abstract:
A smear staining apparatus comprising: a staining section which stains a smear sample with a quantity of stain fluid; and a controller, wherein the controller: receives information regarding a stain state on a smear sample which is stained according to a first staining condition by the staining section; and determines a second staining condition on the basis of the information and a target value which defines a targeted stain state, is disclosed. A smear preparing apparatus, a smear processing system and method for determining staining condition are also disclosed.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a smear staining apparatus for staining a smear sample in which a sample such as blood is applied on a slide glass, a smear preparing apparatus, a smear processing system, and a method for determining the staining condition in staining the smear sample. 
     BACKGROUND 
     A smear staining apparatus for staining a smear sample is conventionally known (e.g., Japanese laid open patent application No. 2001-021468). 
     Japanese laid open patent application No. 2001-021468 discloses a smear staining apparatus for staining a smear sample by immersing the smear sample in a stain fluid bath. In the smear staining apparatus disclosed in this reference, the immersing time is determined by the user so as to stain the sample to a desired density. 
     The concentration of the concentrated stain fluid differs depending on the manufacturer and the manufacturing lot. Thus, an appropriate stain state may not necessarily be obtained after the concentrated stain fluid is replaced even if a constant immersing time is set. The immersing time thus needs to be re-determined if the concentrated stain fluid is replaced. However, although the operator determines the immersing time in the smear staining apparatus disclosed in the above document, the appropriate immersing time may not be determined at one time. Thus, the immersing time needs to be re-determined over and over until an appropriate stain state is obtained, which is a great load on the operator. 
     In view of the above situations, it is a main object of the present invention to provide a smear staining apparatus, a smear preparing apparatus, a smear processing system, and a method for determining the staining condition capable of easily determining an appropriate staining condition. 
     SUMMARY OF THE PRESENT INVENTION 
     A first aspect of the present invention is a smear staining apparatus comprising: a staining section which stains a smear sample with a quantity of stain fluid; and a controller, wherein the controller: receives information regarding a stain state on a smear sample which is stained according to a first staining condition by the staining section; and determines a second staining condition on the basis of the information and a target value which defines a targeted stain state. 
     A second aspect of the present invention is a smear preparing apparatus comprising: a smear preparing section for preparing a smear sample by smearing a sample on a slide glass; a staining section for staining the smear sample prepared by the smear preparing section using a quantity of stain fluid; and a controller, wherein the controller: receives information regarding a stain state on a smear sample which is stained according to a first staining condition by the staining section; and determines a second staining condition on the basis of the information and a target value which defines a targeted stain state. 
     A third aspect of the present invention is a smear processing system comprising: the smear staining apparatus of first aspect; and a smear imaging apparatus for imaging the smear sample stained by the smear staining apparatus to acquire an image, analyzing the obtained image, and outputting information regarding a stain state of the smear sample. 
     A fourth aspect of the present invention is a method of determining a staining condition including steps of: staining a smear sample according to a first staining condition by a staining apparatus for staining a smear sample using a quantity of stain fluid; acquiring information regarding a stain state of the smear sample stained by the staining apparatus according to the first staining condition from a smear imaging apparatus for imaging the stained smear sample and outputting information regarding the stain state; and determining a second staining condition of the staining apparatus based on the obtained information and a target value which defines a targeted stain state. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing an overall configuration of a smear processing system according to the embodiment; 
         FIG. 2  is a plan view showing an internal structure of the blood smear preparing apparatus according to the embodiment; 
         FIG. 3  is a perspective view showing the cassette and the slide glass used in the blood smear preparing apparatus according to the embodiment; 
         FIG. 4  is a perspective view showing the cassette and the slide glass used in the blood smear preparing apparatus according to the embodiment; 
         FIG. 5  is a perspective view showing a first aspirating and discharging unit of the staining section of the blood smear preparing apparatus according to the embodiment; 
         FIG. 6  is a fluid circuit diagram showing the supply path of the liquid supplied to the staining section of the blood smear preparing apparatus according to the embodiment; 
         FIG. 7  is a schematic view showing the configuration of the staining section of the blood smear preparing apparatus according to the embodiment; 
         FIG. 8  is a block diagram showing the configuration of the sample imaging apparatus according to the embodiment; 
         FIG. 9  is a perspective view showing one part of the configuration of the microscope unit of the sample imaging apparatus according to the embodiment; 
         FIG. 10  is a block diagram showing the configuration of the image processing unit of the sample imaging apparatus according to the embodiment; 
         FIG. 11  is a flowchart showing the flow of operation of changing the stain fluid of the blood smear preparing apparatus according to the embodiment; 
         FIG. 12  is a flowchart showing the flow of the blood cell imaging and the image analyzing operation of the sample imaging apparatus according to the embodiment; 
         FIG. 13  is a view showing an example of the blood cell image; 
         FIG. 14  is a view showing an input receiving screen according to the embodiment; 
         FIG. 15A  is a flowchart showing the flow of the staining condition setting process of the blood smear preparing apparatus according to the embodiment (first half); 
         FIG. 15B  is a flowchart showing the flow of the staining condition setting process of the blood smear preparing apparatus according to the embodiment (second half); and 
         FIG. 16  is a flowchart showing the flow of the smear sample preparing and staining process after changing the concentrated stain fluid by the blood smear preparing apparatus according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The preferred embodiment of the present invention will now be described with reference to the drawings. 
     [Configuration of Smear Processing System] 
       FIG. 1  is a perspective view showing an overall configuration of a smear processing system according to the present embodiment. As shown in  FIG. 1 , a smear processing system  100  includes a blood smear preparing apparatus  1  and a sample imaging apparatus  3 . A transport device  2  for transporting a blood sample accommodated in a test tube is arranged on the front side of the blood smear preparing apparatus  1 , where the sample is transported to the blood smear preparing apparatus  1  by the transport device  2  so that the blood smear preparing apparatus  1  uses the relevant sample to prepare a smear sample. The prepared smear sample is imaged by the sample imaging apparatus  3 , and the blood cells are classified through image processing. 
     &lt;Configuration of Blood Smear Preparing Apparatus&gt; 
     The blood smear preparing apparatus  1  aspirates a blood sample and drops it on a slide glass, thinly stretches the blood sample on the slide glass and dries to prepare the smear sample, and then supplies the stain fluid to the smear sample to stain the blood on the slide glass.  FIG. 2  is a plan view showing an internal structure of the blood smear preparing apparatus shown in  FIG. 1 . The blood smear preparing apparatus  1  is connected with five containers  101  to  105  in which the fluid to be used in the staining process are accommodated. In the present embodiment, May-Grunwald stain solution (concentrated stain fluid), diluted solution (phosphate buffer solution in the present embodiment), Giemsa solution (concentrated stain fluid), methanol solution, and sample cleaning solution are accommodated in the containers  101  to  105 , respectively. 
     A shown in  FIG. 2 , the blood smear preparing apparatus  1  includes a control unit  1   a  having a function of controlling the operation for preparing the smear sample of the blood sample. The control unit  1   a  includes a CPU  11  and a memory  12  consisting of a ROM and a RAM. As shown in  FIG. 1 , the blood smear preparing apparatus  1  includes a display operation unit  2   a  including a touch panel, an activation switch  2   b , a power switch  2   c , and a cover  2   d . The control unit  1   a  displays various types of information on the display operation unit  2   a . The transport device  2  is arranged to automatically transport a sample rack  50  accommodating a test tube  51  accommodating the blood to the blood smear preparing apparatus  1 . 
     The overall configuration of the blood smear preparing apparatus  1  will now be described. First, as shown in  FIG. 1 , the blood smear preparing apparatus  1  includes a hand member  1   b  for transporting the test tube  51  accommodating the blood from the transport device  2  side to the blood smear preparing apparatus  1  side. As shown in  FIG. 2 , the blood smear preparing apparatus  1  includes an aspirating and dispensing mechanism section  21 , a smearing section  22 , a resin cassette  23 , a cassette accommodating section  24 , a cassette transporting section  25 , a slide glass inserting section  26 , a staining section  27 , and a storage section  28 . 
     The aspirating and dispensing mechanism section  21  has a function of aspirating the blood from the test tube  51  transported to the blood smear preparing apparatus  1  side by the hand member  1   b  (see  FIG. 1 ) and dropping the aspirated blood on a slide glass  10 . As shown in  FIG. 2 , the aspirating and dispensing mechanism section  21  includes a piazza (aspiration needle)  21   a  for aspirating the blood from the test tube  51 , and a dispensing pipette  21   b  for dispensing the aspirated blood on the slide glass  10 . 
     As shown in  FIG. 2 , the smearing section  22  is arranged to supply the slide glass  10  to a dispensing/smearing position  90 , and to smear and dry the blood dropped on the slide glass  10  and print on the slide glass  10 . The resin cassette  23  is configured so as to be able to accommodate the smeared slide glass  10  and the liquid to be used in the staining step.  FIG. 3  and  FIG. 4  are perspective views showing the cassette and the slide glass used in the blood smear preparing apparatus shown in  FIG. 2 . As shown in  FIG. 3  and  FIG. 4 , the cassette  23  includes a slide glass accommodating hole  23   a  and a stain fluid aspirating and dispensing hole  23   b . The slide glass accommodating hole  23   a  and the stain fluid aspirating and dispensing hole  23   b  are connected inside. 
     Furthermore, as shown in  FIG. 2 , the cassette accommodating section  24  is arranged to convey the cassette  23  into the cassette transporting section  25 , and includes a feed belt  24   a . The cassette transporting section  25  is arranged to transport the cassette  23  conveyed in from the cassette accommodating section  24  to the slide glass inserting section  26  and the staining section  27 . As shown in  FIG. 2 , the cassette transporting section  25  includes a cassette transporting member  25   a  movable in a horizontal direction (A direction in  FIG. 2 ), and a transport path  25   b  for transporting the cassette  23  supplied from the cassette accommodating section  24 . As shown in  FIG. 2 , the slide glass inserting section  26  is arranged to accommodate the slid glass  10  performed with smearing and printing in the slide glass accommodating hole  23   a  of the cassette  23 . 
     As shown in  FIG. 2 , the staining section  27  according to the present embodiment is arranged to perform supply and discharge of the stain fluid and the cleaning solution to the stain fluid aspirating and dispensing hole  23   b  of the cassette  23  transported by the cassette transporting member  25   a , and to lift up and dry the slide glass  10  accommodated in the cassette  23  to perform the staining process on the smeared slide glass  10 . The staining section  27  includes a sending member  71  for sending the cassette  23  transported by the cassette transporting member  25   a  to the staining section  27 , a transport belt  72  for transporting the cassette  23  sent from the sending member  71 , first to fifth aspirating and discharging units  73  to  77  for performing supply and discharge of the stain fluid and the cleaning solution to the cassette  23 , a fan  78   a  for drying the slide glass  10  at the second aspirating and discharging unit  74 , a fan  78   b  for drying the stained slide glass  10 , and a send-out mechanism  79  for sending out the cassette  23  from the transport belt  72  to the transport belt  28   a  side of the storage section  28 . 
     The first aspirating and discharging unit  73  will now be described.  FIG. 5  is a perspective view showing a first aspirating and discharging unit of the staining section of the blood smear preparing apparatus shown in  FIG. 2 . As shown in  FIG. 5 , the first aspirating and discharging unit  73  includes a pipette  73   a  for supplying the methanol solution to the cassette  23 , a pipette supporting member  73   b  for supporting the pipette  73   a , and a drive mechanism  73   e  with a motor  73   c  and a drive belt  73   d  for moving the pipette supporting member  73   b  in the up and down direction. The relevant first aspirating and discharging unit  73  is configured to move the pipette  73   a  downward by the drive mechanism  73   e  to insert into the cassette  23 , and supply the methanol solution. The pipette supporting member  73   b  of the first aspirating and discharging unit  73  is attached with a slide glass gripping member  73   f  for gripping and lifting up the slide glass  10  from the cassette  23 . 
     The second aspirating and discharging unit  74  basically has a structure similar to the first aspirating and discharging unit  73 . The third aspirating and discharging unit  75  to the fifth aspirating and discharging unit  77  have a structure in which the slide glass gripping member  73   f  is removed from the first aspirating and discharging unit  73 . As shown in  FIG. 2 , the second aspirating and discharging  74  to the fifth aspirating and discharging unit  77  respectively includes a pipette  74   a ,  75   a ,  76   a , and  77   a  for supplying May-Grunwald solution, May-Grunwald diluted solution, Giemsa diluted solution, and cleaning solution to the cassette  23 . The pipette  74   a  is also used to aspirate (discharge) the methanol solution supplied by the pipette  73   a  from the cassette  23 . Similarly, the pipette  75   a  is used to aspirate (discharge) the May-Grunwald solution supplied by the pipette  74   a  from the cassette  23 , the pipette  76   a  is used to aspirate (discharge) the May-Grunwald diluted solution supplied by the pipette  75   a  from the cassette  23 , and the pipette  77   a  is used to aspirate (discharge) the Giemsa diluted solution supplied by the pipette  76   a  from the cassette  23 . 
     The supply path of the liquid supplied from each pipette  73   a ,  74   a ,  75   a , and  76   a  of the first aspirating and discharging unit  73  to the fourth aspirating and discharging unit  76  of the staining section  27  according to the present embodiment will now be described in detail.  FIG. 6  is a fluid circuit diagram showing the supply path of the liquid supplied to the staining section shown in  FIG. 2 . As shown in  FIG. 6 , four containers  101  to  104  for accommodating the liquid to be supplied to the staining section are arranged on the supply path according to the present embodiment. Specifically, May-Grunwald solution serving as the concentrated stain fluid is accommodated in the container  101 , the diluted solution (phosphate buffer solution) is accommodated in the container  102 , the Giemsa solution serving as the concentrated stain fluid is accommodated in the container  103 , and the methanol solution is accommodated in the container  104 . 
     As shown in  FIG. 6 , the container  101  accommodating the May-Grunwald solution serving as the concentrated stain fluid is connected to the pipette  74   a  of the second aspirating and discharging unit  74  through a valve  111 , a valve  112 , a chamber  113 , and a valve  114 . An air pressure adjustor  115  is connected to the chamber  113 . The valve  114  is connected to a diaphragm pump  117  connected to an air pressure adjustor  116 . 
     The chamber  113  is arranged on the lower side of the blood smear preparing apparatus  1  (not shown). As shown in  FIG. 6 , the chamber  113  is configured by a tank  113   b  interiorly including a float switch  113   a . When the liquid in the tank  113   b  reaches a defined amount, the float switch  113   a  detects the same. The air pressure adjustor  115  has a function of pressurizing and depressurizing the interior of the chamber  113 , to which the air pressure adjustor  115  is connected. The diaphragm pump  117  has a function of aspirating and discharging a constant amount of solution. A plurality of air pressure adjustors and diaphragm pumps installed in the fluid path according to the present embodiment have functions similar to the air pressure adjustor  115  and the diaphragm pump  117 . 
     The container  101  is also connected to the pipette  75   a  of the third aspirating and discharging unit  75  through the valve  111 , the valve  112 , the chamber  113 , a valve  121 , and a mixed chamber  122 , and a valve  123 . The valve  121  is connected with a diaphragm pump  125  connected to an air pressure adjustor  124 . The valve  123  is connected to a diaphragm pump  127  connected to an air pressure adjustor  126 . The container  102  accommodating the diluted solution (phosphate buffer solution) is connected to the mixed chamber  122  through a valve  131 . The valve  131  is connected with a diaphragm pump  133  connected to an air pressure adjustor  132 . The mixed chamber  122  is arranged to mix the May-Grunwald solution or the concentrated stain fluid accommodated in the container  101  and the diluted solution (phosphate buffer solution) accommodated in the container  102 . 
     The container  103  accommodating the Giemsa solution serving as the concentrated stain fluid is connected to the pipette  76   a  of the fourth aspirating and discharging unit  76  through a valve  141 , a valve  142 , a chamber  143 , a valve  144 , a mixed chamber  145 , and a valve  146 . An air pressure adjustor  147  is connected to the chamber  143 . The valve  144  is connected to a diaphragm pump  149  connected to an air pressure adjustor  148 . The valve  146  is connected to a diaphragm pump  151  connected to an air pressure adjustor  150 . The chamber  143  has a structure similar to the chamber  113  and interiorly includes a float switch  143   a . The chamber  143  is arranged on the lower side of the blood smear preparing apparatus  1  (not shown). As shown in  FIG. 6 , the container  102  accommodating the diluted solution is connected to the mixed chamber  145  through a valve  134 . The valve  134  is connected with a diaphragm pump  136  connected to an air pressure adjustor  135 . The mixed chamber  145  is arranged to mix the Giemsa solution or the concentrated stain fluid accommodated in the container  103  and the diluted solution accommodated in the container  102 . 
     The mixed chamber  122  is connected to a waste chamber  163  through a valve  161 , and the mixed chamber  145  is connected to the waste chamber  163  through a valve  162 . The waste chamber  163  is connected with an air pressure adjustor  164 . The waste chamber  163  has a structure similar to the chamber  113  and interiorly include a float switch  163   a . The float switch  163   a  of the waste chamber  163  is arranged to detect whether or not the discharge of the waste solution stored in the waste chamber  163  is accurately carried out. The chamber  113 , the chamber  143 , and the waste chamber  163  are respectively connected to discharge ports  174 ,  175 ,  176  through valves  171 ,  172 , and  173 . 
     The container  104  accommodating the methanol solution is connected at the middle of the supply path of the May-Grunwald solution from the container  101 , which accommodates the May-Grunwald solution, to the chamber  113  through a valve  181 . The container  104  accommodating the methanol solution is connected at the middle of the supply path of the Giemsa solution from the container  103 , which accommodates the Giemsa solution, to the chamber  143  through a valve  182 . 
     In the present embodiment, the container  104  accommodating the methanol solution is connected to the pipette  73   a  of the first aspirating and discharging unit  73  through a valve  191 , as shown in  FIG. 6 . The valve  191  is connected with the diaphragm pump  193  connected to the air pressure adjustor  192 . Thus, the methanol solution for cleaning accommodated in the container  104  can be supplied to the smear sample (slide glass  10 ) of the first aspirating and discharging unit  73  of the staining section  27  by arranging a path from the container  104  to the pipette  73   a  of the first aspirating and discharging unit  73  through the valve  191 . 
     The storage section  28  shown in  FIG. 2  is arranged to store the cassette  23  in which a stained slide glass  10 , which is stained by the staining section  27 , is accommodated. The storage section  28  includes a transport belt  28   a  for transporting the cassette  23 . 
       FIG. 7  is a schematic view showing the configuration of the staining section  27  of the blood smear preparing apparatus  1  according to the present embodiment. The control unit  1   a  is connected to the motors  73   c  to  77   c  arranged in the first to fifth aspirating and discharging units  73  to  77 , respectively, and drive controls such motors  73   c  to  77   c . Each motor  73   c  to  77   c  is coupled to the pipette  73   a  to  77   a  respectively, so that the pipettes  73   a  to  77   a  move up and down by the operation of the motors  73   c  to  77   c . Furthermore, the pipettes  73   a  to  77   a  perform the aspirating and discharging operation of the fluid by the fluid circuit described above. As described above, the methanol solution, the concentrated May-Grunwald solution, the diluted May-Grunwald solution, the diluted Giemsa solution, and the cleaning solution are respectively supplied to the pipettes  73   a  to  77   a.    
     According to the above configuration, the staining of the smear sample in the blood smear preparing apparatus  1  is generally proceeded in the following manner. First, the immobilization step of immersing the smeared slide glass  10  in the methanol solution or May-Grunwald solution (undiluted solution) for a predetermined time (hereinafter referred to as “immobilization time”) is carried out, and then a first staining step of immersing the smeared and immobilized slide glass  10  in the diluted May-Grunwald solution (hereinafter referred to as “first stain fluid”) for a predetermined time (hereinafter referred to as “first staining time”) is carried out, a second staining step of immersing the slide glass  10  terminated with the first staining step in the Giemsa diluted solution (hereinafter referred to as “second stain fluid”) for a predetermined time (hereinafter referred to as “second staining time”) is carried out, and lastly, a cleaning step of cleaning the slide glass  10  is carried out.) 
     Such blood smear preparing apparatus  1  has a configuration in which the staining condition of the smear sample can be set. The staining condition here is the dilution magnification and the staining time of the concentrated stain fluid. The dilution magnification of the concentrated stain fluid can be set to one of five times, ten times, or twenty times, where the default value is ten times. The average nucleus G value is assumed to change by 30 if the dilution magnification of the concentrated stain fluid is changed one stage. That is, the average nucleus G value is assumed to increase by 30 if the dilution magnification is lowered one stage from ten times to five times or from twenty times to ten times, and the average nucleus G value is assumed to decrease by 30 if the dilution magnification is raised one stage from five times to ten times or from ten times to twenty times. The average nucleus G value is the average value of the G value of the region of the nucleus of the white blood cells in a plurality of blood cell images obtained by imaging the smear sample prepared by the blood smear preparing apparatus  1  with the sample imaging apparatus  3 . 
     The staining time can be set in 11 stages. The staining time that can be set includes the first staining time and the second staining time described above. The setting of the staining time is a combination of the first staining time and the second staining time, and one of the 11 ways of combinations can be set. That is, the first staining time and the second staining time cannot be independently setting changed, and the first staining time and the second staining time are both setting changed. The default value of the staining time is the combination of 5 minutes for the first staining time and 20 minutes for the second staining time, where the first staining time can be setting changed by 0.5 minutes and the second staining time can be setting changed by 2.5 minutes. The lower limit value of the staining time is a combination of 2.5 minutes for the first staining time and 7.5 minutes for the second staining time. The upper limit value of the staining time is a combination of 7.5 minutes for the first staining time and 32.5 minutes for the second staining time. If the staining time is changed one stage, the average nucleus G value is assumed to change by five. For instance, the average nucleus G value increases by five if the default value of “first staining time of 5 minutes and second staining time of 20 minutes” is changed to one stage higher or “first staining time of 5.5 minutes and second staining time of 22.5 minutes”, and the average nucleus G value decreases by five if changed to one stage lower or “first staining time of 4.5 minutes and second staining time of 17.5 minutes”. 
     &lt;Configuration of Sample Transport Device&gt; 
     As shown in  FIG. 1 , the sample transport device  6  is arranged between the blood smear preparing apparatus  1  and the sample imaging apparatus  3 . The sample transport device  6  is arranged to transport the slide glass  10  accommodated in the cassette received from the blood smear preparing apparatus  1  to the sample imaging apparatus  3 . As shown in  FIG. 1 , the sample transport device  6  includes a display unit  6   a  and a power switch  6   b  and a cover  6   c . The sample transport device  6  is configured to convey out the slide glass  10  to be imaged to the sample imaging apparatus  3  through the convey-out port  6   d.    
     &lt;Configuration of Sample Imaging Apparatus&gt; 
       FIG. 8  is a block diagram showing the configuration of the sample imaging apparatus according to the present embodiment.  FIG. 8  schematically shows the configuration of the apparatus, where the arrangement of the sensor, the slide cassette, and the like is slightly different from the actual to facilitate the understanding. For instance, in  FIG. 8 , the sensor for WBC detection and the sensor for autofocus are arranged above and below, but both sensors are actually arranged in substantially the same plane, as shown in  FIG. 9 . 
     The sample imaging apparatus  3  includes a microscope unit  3   a  for imaging an enlarged image of the blood smear sample focused by autofocus, and an image processing unit  3   b  for processing the imaged image to classify the white blood cells in the blood and counting for every classification of the white blood cells. The sample transport device  6  is arranged near the sample imaging apparatus  3 , so that the blood smear sample prepared by the blood smear preparing apparatus  1  is automatically supplied to the microscope unit  3   a  by the sample transport device  6 . 
     &lt;Configuration of Microscope Unit  3   a&gt;   
       FIG. 9  is a perspective view showing one part of the configuration of the microscope unit  3   a . The microscope unit  3   a  includes an objective lens  32  configuring one part of the lens system of the microscope for enlarging the image of the blood thinly stretched and applied on the slide glass  10  mounted on the XY stage  31 . The XY stage  31  for holding the sample (slide glass  10  having the blood applied on the upper surface) is freely movable forward, backward, leftward, and rightward (X direction and Y direction) by a drive unit (not shown) drive controlled by the XY stage drive circuit  33  (see  FIG. 8 ). The objective lens  32  is freely movable up and down (Z direction) by the drive unit (not shown) drive controlled by the objective lens drive circuit  34 . 
     A plurality of slide glasses  10  is accommodated in the slide cassette  35  in a stacked manner, and such slide cassette  35  is transported by the transport unit (not shown) drive controlled by the cassette transport drive circuit  36 . A chuck unit  37  (see  FIG. 9 ) capable of gripping two areas near the ends in the longitudinal direction of the slide glass  10  is arranged on the XY stage  31  in a freely advancing and retreating manner with respect to the slide glass  10  accommodated in the slide cassette  35  stopped at a predetermined position. The slide glass  10  can be gripped by the chuck unit  37 , and the chuck unit  37  can be retreated to pull out the slide glass  10  from the slide cassette  35  and arrange it at a predetermined position of the XY stage  31 . 
     A lamp  38  or a light source is arranged on the lower side of the slide glass  10 , where the light from the lamp  38  passes the blood on the slide glass  10 , and then enters the line sensor  311  for autofocus in which a plurality of pixels is lined in a line, the sensor  312  for white blood cell (WBC) detection in which a plurality of pixels is lined in a line, and the CCD camera  313  through the half mirror  39  and the interference filter  310  arranged on the optical path. The white blood cell detection unit  314  configured by FPGA, ASIC, or the like is connected to the sensor  312  for white blood cell detection, so that the white blood cells are detected by the white blood cell detection unit  314  based on the output signal of the sensor  312 . The focus calculating unit  315  configured by FPGA, ASIC, or the like is connected to the sensor  311  for autofocus, so that the information used in the operation of the autofocus is calculated by the focus calculating unit  315  based on the output signal of the sensor  311  and the operation of the autofocus is carried out based on the relevant information. 
     The microscope unit  3   a  includes a control unit  316  and communication interfaces  317 ,  318 . The control unit  316  includes a CPU and a memory, where the control unit  316  executes the control program stored in the memory to control each mechanism described above. 
     The communication interface  317  is data communicably connected to the image processing unit  3   b  through the communication cable. The communication interface  318  is connected to the CCD camera  313  through the A/D converter  313   a , and is also connected to the image processing unit  3   b  through the communication cable. The image signal (analog signal) output from the CCD camera  313  is A/D converted by the A/D converter  313   a , and the image data (digital data) output from the A/D converter  313   a  is provided to the communication interface  318  and transmitted to the image processing unit  3   b.    
     The microscope unit  3   a  includes a two-dimensional barcode reader  319 . As described above, a two-dimensional barcode indicating the sample ID is printed on the frost part (not shown) of the slide glass  10 , and the two-dimensional barcode of the slide glass  10  introduced to the microscope unit  3   a  is read by the two-dimensional barcode reader  319 . 
     &lt;Configuration of Image Processing Unit  3   b&gt;   
     The configuration of the image processing unit  3   b  will now be described.  FIG. 10  is a block diagram showing the configuration of the image processing unit  3   b . The image processing unit  3   b  is realized by a computer  320 . As shown in  FIG. 10 , the computer  320  includes a main body  321 , an image display unit  322 , and an input unit  323 . The main body  321  includes a CPU  321   a , a ROM  321   b , a RAM  321   c , a hard disc  321   d , a read-out device  321   e , an input/output interface  321   f , a communication interface  321   g , and an image output interface  321   j , where the CPU  321   a , the ROM  321   b , the RAM  321   c , the hard disc  321   d , the read-out device  321   e , the input/output interface  321   f , the communication interface  321   g , and the image output interface  321   j  are connected by a bus  321   k.    
     The read-out device  321   e  can read out the computer program  324   a  for functioning the computer as the image processing unit  3   b  from the portable recording medium  324 , and install the computer program  324   a  in the hard disc  321   d.    
     The image processing unit  3   b  stores the image transmitted from the microscope unit  3   a  in the ROM  321   b  or the hard disc  321   d . The CPU  321   a  causes the image display unit  322  to display the stored image in accordance with the operation from the user. The CPU  321   a  also analyzes the stored image and causes the image display unit  322  to display the analysis result in accordance with the operation from the user. 
     [Operation of Smear Processing System] 
     The operation of the smear processing system  100  according to the present embodiment will now be described. In the blood smear preparing apparatus  1 , the concentrated stain fluid or the diluted solution need to be replaced to a new one if the concentrated stain fluid or the diluted solution is gone or the expiration date for use is overdue. The concentration of the concentrated stain fluid differs depending on the manufacturer. The concentration also differs for every manufacturing lot even if the concentrated stain fluid is manufactured by the same manufacturer. Therefore, the degree of staining tends to differ if the sample is stained under the same staining condition (staining time and dilution magnification) before and after the concentrated stain fluid is replaced. In the blood smear preparing apparatus  1  according to the present embodiment, therefore, the staining conditions are set in the following manner when changing the stain fluid. 
       FIG. 11  is a flowchart showing the flow of operation of changing the concentrated stain fluid of the blood smear preparing apparatus  1  according to the present embodiment. First, the CPU  11  of the control unit  1   a  of the blood smear preparing apparatus  1  determines whether or not the concentrated stain fluid needs to be replaced (step S 101 ). In this process, determination is made that the May-Grunwald solution needs to be replaced if the supply of the May-Grunwald solution to the chamber  113  is not detected by the float switch  113   a  even though the valves  111 ,  112  are opened, and determination is made that the Giemsa solution needs to be replaced if the supply of the Giemsa solution to the chamber  143  is not detected by the float switch  143   a  even though the valves  141 ,  142  are opened. The expiration date for use of the May-Grunwald solution and the Giemsa solution are respectively stored in the memory  12  of the control unit  1   a , so that the need to replace the concentrated stain fluid can be determined by having the CPU  11  determine whether the date for use has expired. If the concentrated stain fluid does not need to be replaced (NO in step S 101 ), the CPU  11  repeats the process of step S 101 . If determined that the concentrated stain fluid needs to be replaced (YES in step S 101 ), the CPU  11  displays an error message notifying that the concentrated stain fluid needs to be replaced on the display operation unit  2   a  (step S 102 ). 
     The CPU  11  determines whether or not the concentrated stain fluid is replaced (step S 103 ). Determination is made that the concentrated stain fluid is replaced when the error message displayed on the display operation unit  2   a  is closed by the operator. If the concentrated stain fluid is not replaced (NO in step S 103 ), the CPU  11  repeats the process of step S 103 . If determined that the concentrated stain fluid is replaced (YES in step S 103 ), the CPU  11  displays the OK button and the NO button on the display operation unit  2   a  along with the message “Concentrated stain fluid is replaced. Perform test staining?”, and determines whether or not the execution of the test staining is instructed (step S 104 ). When the selection of the OK button is detected and the instruction to execute the test staining is made (YES in step S 104 ), the CPU  11  proceeds the process to step S 105 . When the selection of the NO button is detected, and the instruction not to execute the test staining is made (NO in step S 104 ), the CPU  11  terminates the process. In this case, the setting of the staining conditions is not replaced, and the staining conditions up to now are maintained. 
     In step S 105 , the CPU  11  executes the sample preparing process (step S 105 ). In the sample preparing process, the blood is aspirated by the aspirating and dispensing mechanism section  21  from the test tube  51  transported by the transport device  2 , and the aspirated blood is dropped on the slide glass  10 . 
     The blood used in the test staining is preferably a fresh blood collected from a healthy person. The fresh blood collected from the healthy person is preferably the blood which measurement value of each measurement item falls within a predetermined range when measured with respect to a plurality of measurement items in the blood cell analyzer and the blood collected within 24 hours. 
     As hereinafter described, the smear sample stained by the test staining is supplied to the sample imaging apparatus  3 , and the average nucleus G value indicating the stain state of the relevant smear sample is obtained. The average nucleus G value is obtained by acquiring the nucleus G value of the neutrophil cells of the white blood cells for a plurality of neutrophil cells, and obtaining the average value of the plurality of nucleus G values. The neutrophil cells are blood cells that occupy 60% of the white blood cells and are always contained in the blood collected from the healthy person, where barely any difference is recognized in the aspect of the neutrophil cells (e.g., easiness to stain) between the samples unless the blood is not degraded. Therefore, a stable average nucleus G value is always obtained only when the fresh blood collected from the healthy person is used in the test staining. 
     The blood dropped on the slide glass  10  is smeared on the slide glass  10  by the smearing section  22  and then dried. The smear sample obtained in such manner is inserted to the cassette  23 , and the test staining is carried out by the staining steps described above in the staining section  27 . In the test staining, the staining conditions of the default values are used. That is, the dilution magnification of the concentrated stain fluid is ten times, the first staining time is five minutes, and the second staining time is 20 minutes. 
     The test staining process will be described in detail. First, when the slide glass  10  that is smeared with the sample is sent to the staining section  27 , the immobilization step described above is carried out. In the immobilization step, the methanol solution or the concentrated May-Grunwald solution is discharged into the cassette  23 , to which the slide glass  10  is inserted, when the pipette  73   a  of the first aspirating and discharging unit  73  or the pipette  74   a  of the second aspirating and discharging unit  74  are operated. The slide glass  10  that is smeared with the sample is immersed in the methanol solution or the concentrated May-Grunwald solution until the immobilization time has elapsed from when the methanol solution or the May-Grunwald solution is supplied into the cassette  23 . After the immobilization time has elapsed from when the methanol solution or the May-Grunwald solution is supplied into the cassette  23 , the smeared slide glass  10  is lifted up from the slide glass accommodation hole  23   a  of the cassette  23  by the second aspirating and discharging unit  74 , and the air is blown to the smear surface of the slide glass  10  by the fan  78   a  to dry the fluid component on the smear surface. The immobilization process of the smear sample by the methanol solution is thereby terminated. The time (immobilization time) from when the smeared slide glass  10  is immersed in the methanol solution or the undiluted May-Grunwald solution until the slide glass  10  is lifted up by the second aspirating and discharging unit  74  is about 20 seconds to about 120 seconds. The methanol solution or the May-Grunwald solution inside the cassette  23  is discharged. This is carried out when the methanol solution is aspirated by the pipette  74   a  if the methanol solution is supplied into the cassette  23 , and carried out when the May-Grunwald solution is aspirated by the pipette  75   a  if the May-Grunwald solution is supplied into the cassette  23 . Thereafter, the slide glass  10  is returned to the slide glass accommodation hole  23   a  of the cassette  23 . 
     The first staining step is then carried out. When supplying the diluted May-Grunwald solution (undiluted solution of first stain fluid) to the pipette  75   a  of the third aspirating and discharging unit  75 , the flow path between the chamber  113  and the diaphragm pump  125  is in the open state by the valve  121  shown in  FIG. 6 . The interior of the diaphragm pump  125  is depressurized by the air pressure adjustor  124 . A constant amount of the May-Grunwald solution of the chamber  113  is aspirated by the diaphragm pump  125 . Thereafter, the flow path between the diaphragm pump  125  and the mixed chamber  122  is in the opened state by the valve  121 . The interior of the diaphragm pump  125  is pressurized by the air pressure adjustor  124 . The May-Grunwald solution of the diaphragm pump  125  is moved to the mixed chamber  122 . Thereafter, the flow path between the diaphragm pump  125  and the mixed chamber  122  is in the shielded state by the valve  121 . The movement of the May-Grunwald solution of the chamber  113  to the mixed chamber  122  is thereby terminated. 
     The diluted solution (phosphate buffer solution) of the container  102  is then moved to the mixed chamber  122  to dilute the May-Grunwald solution of the mixed chamber  122 . Specifically, the flow path between the container  102  and the diaphragm pump  133  is in the opened state by the valve  131 . The interior of the diaphragm pump  133  is depressurized by the air pressure adjustor  132 . A constant amount of the diluted solution of the container  102  is aspirated by the diaphragm pump  133 . Thereafter, the flow path between the diaphragm pump  133  and the mixed chamber  122  is in the opened state by the valve  131 . The interior of the diaphragm pump  133  is pressurized by the air pressure adjustor  132 . The diluted solution of the diaphragm pump  133  is moved to the mixed chamber  122 . Thereafter, the flow path between the diaphragm pump  133  and the mixed chamber  122  is in the shielded state by the valve  131 . The movement of the diluted solution of the container  102  to the mixed chamber  122  is terminated. The first stain fluid of the dilution magnification of ten times, which is the default value, is prepared by controlling the repeating number of times of the constant amount supplying operation of the May-Grunwald solution and the diluted solution to the mixed chamber  122 . 
     After the flow path between the mixed chamber  122  and the diaphragm pump  127  is opened by the valve  123 , the interior of the diaphragm pump  127  is depressurized by the air pressure adjustor  126 . A constant amount of the first stain fluid of the mixed chamber  122  is thereby aspirated by the diaphragm pump  127 . Thereafter, the flow path between the diaphragm pump  127  and the mixed chamber  122  is shielded, and the flow path between the diaphragm pump  127  and the pipette  75   a  of the third aspirating and discharging unit  75  is opened by the valve  123 . The interior of the diaphragm pump  127  is pressurized by the air pressure adjustor  126 . The first stain fluid in the diaphragm pump  127  is supplied from the pipette  75   a  of the third aspirating and discharging unit  75  to the cassette  23  (see  FIG. 2 ). 
     The slide glass  10  that is smeared with the sample is immersed in the first stain fluid while the cassette  23  is transported by the transport belt  72  and the staining of the sample by the first stain fluid is carried out until the first staining time has elapsed from when the first stain fluid is supplied into the cassette  23 . In the test staining, the first staining time is five minutes, which is the default value. After the elapse of the first staining time, the first stain fluid is aspirated by the pipette  76   a  and the first stain fluid in the cassette  23  is discharged. 
     The second staining step is then carried out. When supplying the Giemsa diluted solution (undiluted solution of second stain fluid) to the pipette  76   a  of the fourth aspirating and discharging unit  76  of the staining section  27 , the valves  141  and  142  shown in  FIG. 6  are first opened from the initial state (all valves are shielded), and the interior of the chamber  143  is depressurized by the air pressure adjustor  147 . The Giemsa solution of the container  103  is thereby aspirated to the chamber  143 . The float switch  143   a  installed in the chamber  143  is turned ON with the flow of the Giemsa solution to the chamber  143 . The valves  141  and  142  are then shielded, and the depressurization by the air pressure adjustor  147  is released. The movement of the Giemsa solution of the container  103  to the chamber  143  is then terminated. 
     The Giemsa solution of the chamber  143  is moved to the mixed chamber  145 . Specifically, the flow path between the chamber  143  and the diaphragm pump  149  is first opened by the valve  144 . The interior of the diaphragm pump  149  is depressurized by the air pressure adjustor  148 . A constant amount of Giemsa solution of the chamber  143  is thereby aspirated by the diaphragm pump  149 . Thereafter, the flow path between the diaphragm pump  149  and the mixed chamber  145  is in the opened state by the valve  144 . The interior of the diaphragm pump  149  is pressurized by the air pressure adjustor  148 . The Giemsa solution of the diaphragm pump  149  is moved to the mixed chamber  145 . Thereafter, the flow path between the diaphragm pump  149  and the mixed chamber  145  is in the shielded state by the valve  144 . The movement of the Giemsa solution of the chamber  143  to the mixed chamber  145  is then terminated. 
     The diluted solution (phosphate buffer solution) of the container  102  is then moved to the mixed chamber  145  to dilute the Giemsa solution of the mixed chamber  145 . Specifically, the flow path between the container  102  and the diaphragm pump  136  is in the opened state by the valve  134 . The interior of the diaphragm pump  136  is depressurized by the air pressure adjustor  135 . A constant amount of the diluted solution of the container  102  is aspirated by the diaphragm pump  136 . Thereafter, the flow path between the diaphragm pump  136  and the mixed chamber  145  is in the opened state by the valve  134 . The interior of the diaphragm pump  136  is pressurized by the air pressure adjustor  135 . The diluted solution of the diaphragm pump  136  is moved to the mixed chamber  145 . Thereafter, the flow path between the diaphragm pump  136  and the mixed chamber  145  is in the shielded state by the valve  134 . The movement of the diluted solution of the container  102  to the mixed chamber  145  is terminated. The Giemsa solution is mixed with the diluted solution in the mixed chamber  145  to become the Giemsa diluted solution (second stain fluid). The second stain fluid of the dilution magnification of ten times, which is the default value, is prepared by controlling the repeating number of times of the constant amount supplying operation of the Giemsa solution and the diluted solution to the mixed chamber  145 . 
     After the flow path between the mixed chamber  145  and the diaphragm pump  151  is opened by the valve  146 , the interior of the diaphragm pump  151  is depressurized by the air pressure adjustor  150 . A constant amount of the second stain fluid of the mixed chamber  145  is thereby aspirated by the diaphragm pump  151 . Thereafter, the flow path between the diaphragm pump  151  and the mixed chamber  145  is shielded, and the flow path between the diaphragm pump  151  and the pipette  76   a  of the fourth aspirating and discharging unit  76  is opened by the valve  146 . The interior of the diaphragm pump  151  is pressurized by the air pressure adjustor  150 . The Giemsa diluted solution in the diaphragm pump  151  is supplied from the pipette  76   a  of the fourth aspirating and discharging unit  76  to the cassette  23  (see  FIG. 2 ). 
     The slide glass  10  is then immersed in the second stain fluid while the cassette  23  is transported by the transport belt  72  and the staining of the sample by the second stain fluid is carried out until the second staining time has elapsed from when the second stain fluid is supplied into the cassette  23 . In the test staining, the second staining time is twenty minutes, which is the default value. After the elapse of the second staining time, the second stain fluid is aspirated by the pipette  77   a  and the second stain fluid in the cassette  23  is discharged. 
     The cleaning step is then carried out. After the cleaning solution is dispensed to the stain fluid aspirating and dispensing hole  23   b  of the cassette  23  by the pipette  77   a , the stained slide glass  10  aspirated by the pipette  77   a  is cleaned. The stained slide glass  10  is then dried with the fan  78   b . The staining process is thereby completed. 
     The cassette  23  accommodating the stained slide glass  10  is then sequentially sent to the transport belt  28   a  of the storage section  28  from the transport  72 . The cassette  23  is transported by the transport belt  28   a  of the storage section  28 . 
     After the relevant sample preparing process is completed, the stained smear sample that is prepared is automatically supplied from the blood smear preparing apparatus  1  to the microscope unit  3   a  by the sample transport device  6 .  FIG. 12  is a flowchart showing the flow of the blood cell imaging and the image analyzing operation of the sample imaging apparatus  3  according to the present embodiment. The sample imaging apparatus  3  detects the white blood cells in the blood applied to the slide glass  10  with the sensor  312  while moving the slide glass  10  in the X direction and the Y direction with the XY stage  31  (step S 201 ). The control unit  316  then executes the autofocus operation (step S 202 ), and images the stained blood cells (step S 203 ). 
     The control unit  316  transmits the obtained blood cell image to the image processing unit  3   b . The CPU  321   a  of the image processing unit  3   b  stores the received blood cell image in the ROM  321   b  or the hard disc  321   d , and calculates various characteristic parameters of the white blood cells based on the blood cell image (step S 204 ). The characteristic parameter includes the area, the number of nucleus, the bumps, the color tone, and the concentration (unevenness) of the nucleus of the white blood cell that can be obtained based on the color signal (G, B, R) of the image, the area, the color tone, and the concentration (unevenness) of the cell cytoplasm of the white blood cells, as well as the area ratio and the concentration ratio of the nucleus and the cell cytoplasm. 
     The CPU  321   a  then classifies the type of white blood cells based on the acquired characteristic parameter (step S 205 ). Specifically, for example, the types of white blood cells can be gradually narrowed down by sequentially comparing with the criterion value defined in advance for each parameter with respect to some of the characteristic parameters of the white blood cells. The imaged white blood cells is thus subjected to the classification of mature white blood cells such as lymphocytes, monocytes, acidocytes, basocytes, neutrophil cells (bacillary, lobulated), and the classificaiton of immature white blood cells such as gemmules, young granulocytes, and atypical lymphocytes, and the classification of erythoblasts. 
       FIG. 13  is a view showing an example of the blood cell image. A blood cell image  160 A of when the May Giemsa staining is performed includes a blood cell image  161  with a nucleus region  161   a  and a cytoplasm region  161   b . The nucleus region  161   a  of the blood cell image  160 A has different color shades depending on the concentration of the stain fluid and the staining time. The luminance value of the specific color component (green component in the present embodiment) of the nucleus region  161   a  represents the characteristic of the nucleus region  161   a  of the blood cell image and shows the stain state of the blood cell. 
     The image processing unit  3   b  acquires the stain state information showing the stain state. This will be specifically described below. The CPU  321   a  determines whether or not the white blood cells in the blood cell image is classified to the neutrophil cells based on the classification of step S 205  (step S 206 ). If the white blood cells are classified to the neutrophil cells (YES in step S 206 ), the luminance value (hereinafter referred to as G value) of the green component is acquired of the color components (red: R, green: G, blue: B) of each pixel in the nucleus region of the white blood cells in the blood cell image after the correction, the average value of the G values acquired for all the pixels of the nucleus region is calculated, and the obtained value (nucleus G value) is stored in the RAM  321   c  (step S 207 ). The CPU  321   a  then proceeds the process to step S 208 . 
     If the white blood cells in the blood cell image are not classified to the nuetrophil cells in step S 206  (NO in step S 206 ), the CPU  321   a  proceeds the process to step S 208 . In step S 208 , the CPU  321   a  determines whether or not the nucleus G value is calculated for a predetermined number (e.g., 100) of blood cell images (step S 208 ). If a predetermined number of nucleus G value is not obtained (NO in step S 208 ), the process returns to step S 201 , and the processes of steps S 201  to S 208  are again executed. 
     If a predetermined number of nucleus G values is obtained (YES in step S 208 ), the CPU  321   a  calculates the average nucleus G value or the average value of the obtained nucleus G values (step S 209 ). The average nucleus G value becomes the information indicating the stain state of the smear sample stained according to the default staining condition in the staining section  27 . The CPU  321   a  displays the obtained blood cell image and the average nucleus G value on the image display unit  322  (step S 210 ), and terminates the process. 
     Returning back to  FIG. 11 , after the sample preparing process of step S 105  is completed, the CPU  11  of the blood smear preparing apparatus  1  displays an input receiving screen for receiving the input of the nucleus G value to become the target (hereinafter referred to as “target nucleus G value”) and the average nucleus G value displayed on the image processing unit  3   b  on the display operation unit  2   a  (step S 106 ).  FIG. 14  is a view showing the input receiving screen. The input receiving screen  200  includes an input area  201  for inputting the target nucleus G value, an input area  202  for inputting the average nucleus G value, and a software key  203  for inputting numbers and the like. The target nucleus G value and the average nucleus G value are respectively a numerical value in the range of 0 to 125. Thus, the numerical value in the range of 0 to 125 can be input to the input areas  201 ,  202 . The user operates the software key  203  displayed on the display operation unit  2   a  to input the target nucleus G value showing the nucleus G value of the appropriately stained smear sample to the input area  201 , and to input the average nucleus G value displayed on the image processing unit  3   b  to the input area  202 , and selects the enter key. The CPU  11  determines whether or not the inputs of the target nucleus G value and the average nucleus G value are received (step S 107 ), and repeats the process of step S 107  until input if the target nucleus G value and the average nucleus G value are not input (NO in step S 107 ). If the target nucleus G value and the average nucleus G value are input (YES in step S 107 ), the CPU  11  executes the following staining condition setting process (step S 108 ). If the target nucleus G value is not input and the average nucleus G value is input, the target nucleus G value of default value (e.g., 70) is automatically set. 
     The nucleus G value indicating the stain state of the appropriately stained smear sample is input for the target nucleus G value. The nucleus G value of the stained smear sample subjected to staining before changing the concentrated stain fluid can be used for such nucleus G value. Such operation is carried out in the following manner. 
     A plurality of blood cells images of the neutrophil cells obtained by imaging the stained smear sample stained before changing the concentrated stain fluid is stored in the image processing unit  3   b  of the sample imaging apparatus  3 . The user operates the image processing unit  3   b  to display the stored blood cell images on the image display unit  322 , and selects a plurality of blood cell images stained to the desired stain state. The blood cell image selected here is preferably the blood cell image obtained by imaging the smear sample prepared using a fresh blood collected from a healthy person and then stained. The plurality of blood cells images to be selected may be obtained from one stained smear sample or may be respectively obtained from different stained smear samples, and are not particularly limited. 
     The user instructs the image processing unit  3   b  to execute the process (process of step S 207  of  FIG. 12 ) for obtaining the average nucleus G value of the plurality of selected blood cell images. The image processing unit  3   b  obtains the nucleus G value for each of the plurality of blood cell images, and displays the average value thereof on the image display unit  322 . The user inputs the displayed value in the input receiving screen as the target nucleus G value. 
     The staining condition capable of realizing substantially the same stain state as the desired stain state obtained before changing the concentrated stain fluid can be set by inputting the target nucleus G value and setting the staining conditions. 
       FIG. 15A  and  FIG. 15B  are flowcharts showing the flow of the staining condition setting process. The CPU  11  performs a calculation to subtract the average nucleus G value from the input target nucleus G value to calculate a difference A (step S 111 ). The CPU  11  then determines whether or not the difference A is zero (step S 112 ), and sets the dilution magnification and the staining time (first staining time and second staining time), which are the staining conditions, to default values (step S 113 ) if the difference A is zero (YES in step S 112 ), and returns the process to the call-out address of the staining condition setting process in the main routine. 
     If the difference A is not zero (NO in step S 112 ), the CPU  11  determines whether or not the difference A is greater than zero (positive) (step S 114 ), and determines whether or not the difference A is greater than or equal to 30 (step S 115 ) if the difference A is positive (YES in step S 114 ). If the difference A is greater than or equal to 30 (YES in step S 115 ), the CPU  11  determines whether or not the difference A is greater than 55 (step S 116 ). If the difference A is greater than 55 (YES in step S 116 ), abnormality that cannot be handled by changing the staining condition is assumed to have occurred, and hence the CPU  11  causes the display operation unit  2   a  to display the error message (step S 117 ) and returns the process to the call-out address of the staining condition setting process in the main routine. 
     If the difference is greater than or equal to 30 and smaller than or equal to 55 (NO in step S 116 ), the CPU  11  performs a calculation of subtracting 30 from the difference A and dividing the result thereof by five (step S 118 ). If there is a remained in the process of step S 118 , such remained is cut off. That is, an integer in the range of 0 to 5 is obtained in the process of step S 118 . The CPU  11  then sets the staining conditions (step S 119 ). In the process of step S 119 , the dilution magnification is lowered by one stage and the staining time is raised by the number obtained in the process of step S 118 . That is, the dilution magnification is set to 5 times, which is one stage lower than the default value of ten times, and the staining time is set to a value higher than the default value of five minutes for the first staining time and twenty minutes for the second staining time by the number obtained in the process of step S 118 , and the set values are stored in the memory  12 . After the setting of the staining conditions is completed, the CPU  11  returns the process to the call-out address of the staining condition setting process in the main routine. 
     If the difference A is smaller than 30 in step S 115  (NO in step S 115 ), the CPU  11  performs a calculation of dividing the difference A by five (step S 120 ). If there is a remained in the process of step S 120 , such remained is cut off. That is, an integer in the range of 0 to 5 is obtained in the process of step S 120 . The CPU  11  then sets the staining conditions (step S 121 ). In the process of step S 121 , the dilution magnification is not changed and the staining time is raised by the number obtained in the process of step S 120 . That is, the dilution magnification is set to the default value of ten times, and the staining time is set to a value higher than the default value of five minutes for the first staining time and twenty minutes for the second staining time by the number obtained in the process of step S 120 , and the set values are stored in the memory  12 . After the setting of the staining conditions is completed, the CPU  11  returns the process to the call-out address of the staining condition setting process in the main routine. 
     If the difference A is negative in step S 114  (NO in step S 114 ), the CPU  11  determines whether or not the difference A is smaller than or equal to −30 (step S 122 ). If the difference A is smaller than or equal to −30 (YES in step S 122 ), the CPU  11  determines whether or not the difference A is smaller than −55 (step S 123 ). If the difference A is smaller than −55 (YES in step S 123 ), abnormality that cannot be handled by changing the staining condition is assumed to have occurred, and hence the CPU  11  causes the display operation unit  2   a  to display the error message (step S 124 ) and returns the process to the call-out address of the staining condition setting process in the main routine. 
     If the difference is smaller than or equal to −30 and greater than or equal to −55 (NO in step S 123 ), the CPU  11  performs a calculation of adding 30 to the difference A and dividing the result thereof by five (step S 125 ). If there is a remained in the process of step S 125 , such remained is cut off. That is, an integer in the range of 0 to −5 is obtained in the process of step S 125 . The CPU  11  then sets the staining conditions (step S 126 ). In the process of step S 126 , the dilution magnification is raised by one stage and the staining time is lowered by the number obtained in the process of step S 125 . That is, the dilution magnification is set to twenty times, which is one stage higher than the default value of ten times, and the staining time is set to a value lower (value lower by one stage if −1) than the default value of five minutes for the first staining time and twenty minutes for the second staining time by the number obtained in the process of step S 125 , and the set values are stored in the memory  12 . After the setting of the staining conditions is completed, the CPU  11  returns the process to the call-out address of the staining condition setting process in the main routine. 
     If the difference A is smaller than −30 in step S 122  (NO in step S 122 ), the CPU  11  performs a calculation of dividing the difference A by five (step S 127 ). If there is a remained in the process of step S 127 , such remained is cut off. That is, an integer in the range of 0 to −5 is obtained in the process of step S 127 . The CPU  11  then sets the staining conditions (step S 128 ). In the process of step S 128 , the dilution magnification is not changed and the staining time is lowered by the number obtained in the process of step S 127 . That is, the dilution magnification is set to the default value of ten times, and the staining time is set to a value lower (value lower by one stage if −1) than the default value of five minutes for the first staining time and twenty minutes for the second staining time by the number obtained in the process of step S 127 , and the set values are stored in the memory  12 . After the setting of the staining conditions is completed, the CPU  11  returns the process to the call-out address of the staining condition setting process in the main routine. 
     After the staining condition setting process is terminated, the CPU  11  terminates the process. 
     After the staining conditions are set, the set values are stored in the memory  12  of the control unit  1   a , and used in the subsequent staining process of the smear sample. 
       FIG. 16  is a flowchart showing the flow of the smear sample preparing and staining process after changing the concentrated stain fluid by the blood smear preparing apparatus  1  according to the present embodiment. The CPU  11  determines whether or not the preparing and the staining of the smear sample are instructed from the user (step S 301 ). If not instructed (NO in step S 301 ), the process of step S 301  is repeated until instruction is made. The CPU  11  determines that the instruction is made when the test tube  51  accommodating the blood is set in the transport device  2  by the user, and the preparing and the staining of the smear sample are instructed from the display operation unit  2   a  (YES in step S 301 ), and reads out the set values of the staining conditions stored in the memory  12  (step S 302 ). The CPU  11  then executes the sample preparing and staining process (step S 303 ). In the sample preparing process, the blood is aspirated by the aspirating and dispensing mechanism section  21  from the test tube  51  transported by the transport device  2 , and the aspirated blood is dropped on the slide glass  10 . The blood dropped on the slide glass  10  is smeared on the slide glass  10  by the smearing section  22  and then dried. The smear sample obtained in such manner is inserted to the cassette  23 , and the staining is carried out by the staining section  27 . In the staining process, the smear sample is stained according to the set values of the staining conditions read from the memory  12  in step S 302  using the undiluted solution of the stain fluid same as the concentrated stain fluid used in the test staining. Specifically, the new concentrated stain fluid that was replaced is diluted according to the set dilution magnification to prepare first and second stain fluids. The smear sample is subjected to staining by the first stain fluid in the set first staining time, and to staining by the second stain fluid in the set second staining time. After the smear sample preparing and the staining process is terminated, the CPU  11  terminates the process. 
     According to such configuration, the operator inputs the target nucleus G value and the average nucleus G value, and can set the staining conditions with which the nucleus G value close to the target nucleus G value can be expected to be obtained according to the difference A of the input target nucleus G value and the average nucleus G value. Therefore, the operator can easily set the appropriate staining conditions. Skilled training is not required to set the staining conditions, and the setting of the staining conditions can be prevented from varying for every operator. 
     Furthermore, the staining state can be greatly changed by changing the dilution magnification and the staining state can be finely tuned by changing the staining time by individually setting the dilution magnification and the staining time. Therefore, the operator can finely and accurately set the desired staining conditions. 
     Other Embodiments 
     In the embodiment described above, the average nucleus G value displayed on the image processing unit  3   b  is input to the blood smear preparing apparatus  1  by the user, but this is not the sole case. The blood smear preparing apparatus  1  and the sample imaging apparatus  3  may be communicably connected, the average nucleus G value may be obtained by the sample imaging apparatus is provided to the blood smear preparing apparatus by communication, and the blood smear preparing apparatus  1  automatically may set the staining condition using the average nucleus G value. 
     In the embodiment described above, a configuration of performing the test staining and the setting of the staining conditions when changing the undiluted solution of the stain fluid has been described, but is not limited thereto. The test staining and the setting of the staining conditions may be performed in an arbitrary period, and for example, the test staining and the setting of the staining conditions may be carried out in the maintenance task of the blood smear preparing apparatus  1 . 
     In the embodiment described above, a configuration of setting the staining conditions of the blood smear preparing apparatus  1  using the average nucleus G value related to the G value of the region of the nucleus of the blood cell image has been described, but is not limited thereto. The value (average nucleus B value or average nucleus R value) obtained by averaging the B values or the R values of the region of the nucleus of the blood cell image for every sample may be obtained instead of the average nucleus G value, and the staining conditions may be set using the average nucleus B value or the average nucleus R value. The blood cell image of the density image may be obtained, and the staining conditions may be set using the average value of the brightness (luminance) of the region of the nucleus of the blood cell image. The staining conditions may be set using the nucleus G value (or the nucleus B value or the nucleus R value) calculated from one blood cell image instead of the average value of the nucleus G value calculated from each of the plurality of blood cell images, or the blood cell image or one density image may be obtained and the staining conditions may be set using the average value of the brightness of the region of the nucleus of the blood cell image. Furthermore, the G value (or B value, R value, or brightness of density image) of one pixel in the region of the nucleus of the blood cell image may be used as a representative value, and the staining conditions may be set using such value. 
     In the embodiment described above, the input of the target nucleus G value and the average nucleus G value is received, and the staining conditions are set based on the input target nucleus G value and the average nucleus G value, but this is not the sole case. The target nucleus G value may be stored as a fixed value, the input of only the average nucleus G value may be requested, and the staining conditions may be set based on the input average nucleus G value and the stored target nucleus G value. The user may set the target nucleus G value, the input of the target nucleus G value may not be requested when requesting for the input of the average nucleus G value, and the staining conditions may be set using the input average nucleus G value and the target nucleus G value stored as the set value. 
     In the embodiment described above, the dilution magnification is determined by the magnitude of the difference A between the target nucleus G value and the average nucleus G value, and the staining time is determined by performing a predetermined calculation using the difference A, but this is not the sole case. The set value may be changed from a default value by the amount of change of the staining condition corresponding to the difference A with reference to a table storing the relationship of the difference A, and the amount of change from the default value of the staining condition (dilution magnification, first staining time, and second staining time). 
     In the embodiment described above, the staining conditions are reset to the default setting uniformly at the time of test staining, but this is not the sole case. For instance, the test staining may be carried out based on the setting of immediately before the test staining. 
     In the embodiment described above, the configuration in which the blood smear preparing apparatus for preparing the smear sample sets the staining conditions has been described, but this is not the sole case. The smear staining apparatus, which does not have a function of preparing a smear sample but has a function of staining the smear sample, may receive the input of the target nucleus G value and the average nucleus G value, and set the staining conditions based on the input target nucleus G value and the average nucleus G value. 
     INDUSTRIAL APPLICABILITY 
     The smear staining apparatus, the smear preparing apparatus, the smear processing system, and the method of determining the staining conditions of the present invention are useful as a smear staining apparatus for staining a smear sample in which a sample such as blood is smeared on a slide glass, a smear preparing apparatus and a smear processing system, as well, as a method of determining the staining conditions in the staining of the smear sample.