Patent Publication Number: US-2006012872-A1

Title: Confocal microscope, fluorescence measuring method and polarized light measuring method using cofocal microscope

Description:
TECHNICAL FIELD  
      The present invention relates to a confocal microscope used for fluorescent observation or the like of biological tissues and organisms, a confocal microscope using liquid crystal device, the method of fluorescent measurement of microarray substrates by the confocal microscope using liquid crystal device, and to the method of polarized light measurement by the confocal microscope using liquid crystal device, which are of high sensitivity, excel in resolution in the horizontal and the depth directions, and are capable of dynamic observation in a wide range.  
     BACKGROUND ART  
      Heretofore, confocal microscopes have been used for the observation of fluorescent luminescence from the biological tissue samples in which biological tissues and fluorescent reagents are added in the fields of study of biological science. Since confocal microscopes have high resolution in the depth direction, they are mainly used for three dimensional observation of biological samples.  
       FIG. 19  shows a conventional example 1 of a confocal microscope disclosed in the Japanese Patent Application (JP H05-60980A (1993)). Laser light  161  is reflected by a beam splitter  162 , and focused on a sample  164  by an objective lens  163 , and the reflected light or fluorescence  166  from the sample  164  transmits a beam splitter  162 , passes a mirror  167  and a lens  169 , and enters a detector  171 . Here, by locating a pinhole  170  before the detector  171 , a clear image can be obtained by removing a light flux generated from other than a focal plane. In order to observe whole of the sample  164 , the sample  164  is moved in plane on the stage on which is it set, that is, observed by scanning  172 .  
      For a confocal microscope, the method to scan at high speed without moving a sample is the Nipkow disc system invented by Paul Nipkow in  1884 .  FIG. 20  illustrates the principle of scanning system of a multi-confocal microscope using the Nipkow disc in accordance with a conventional example 2 disclosed in the Japanese Patent Application (JP H05-60980A (1993)), “DNA Microarray substrate”, written by Mark Schena, translated by Ikunoshin Kato, published by Maruzen, 2000, pp. 19-45, and “Confocal Microscope, Laser Microscope Scanner and CCD Camera”, written by Shinichiro Kawamura and three co-authors, Yokokawa Gihou, 2001, Vol. 45, No. 2, p. 112-114).  
      A multi-confocal microscope  180  lets laser light  181  into a confocal scanning apparatus  190 . The confocal scanning apparatus  190  is made up with a light collecting disc  191  and a pinhole disc  192  made with two discs, a drum  194 , and a beam splitter  182 . The light collecting disc  191  and the pinhole disc  192  are held with the drum  194 , and are rotated by a motor  195 .  
      Here, the laser light  181  passes through a number of pinholes  193  provided to the light collecting disc  191 . Thus passed lights form a plurality of foci on the object  184  by a lens  183  via a beam splitter  182 , and the reflected light from the object  184  is focused on a camera  186  by a lens  185  with its path being bent 90 degrees with respect to the inlet direction via a beam splitter  182 . Thereby, the efficiency of the utilized light is enhanced, and a multi-confocal microscope by a plurality of simultaneous focal detections was realized.  
       FIG. 21  illustrates the makeup of a multi-confocal microscope in accordance with a conventional example 3 disclosed in the Japanese Patent Application (JP H05-210051A (1993)). A multi-confocal microscope  200  has the similar optical system as that of the conventional example 1 of  FIG. 18 , but differs in that a liquid crystal cell  203  is located in the incident light path. The incident light  201  passes a beam splitter  202 , and is focused on the sample  205  by an objective lens  204  via the liquid crystal cell  203 . The reflected light from the sample  205  passes a lens  207  via a beam splitter  202 , and the reflected light  208  is focused on a camera  209 .  
      Here, the incident light  201  passes an open inlet part  203   a  that is a pixel of liquid crystal, and is focused at a point of  210   a  of the sample  205 . Next, another pixel  203   b  of liquid crystal is opened, then the incident light is focused at a point of  210   b  of the sample  205 . Thus, scanning over the sample  205  is conducted, in turn on the pixels on the liquid crystal cell plane, by so-called X-Y scanning to turn the incident light  201  on and off.  
      In the Japanese Patent Application (JP 2001-108684A and JP 2001-208688A), a DNA inspection apparatus is disclosed which has a multi-spot array to make the incident light source a multi-beam, and it detects the confocal of the fluorescence generated by the irradiated excitation light.  
      Incidentally, the confocal microscope of a sample scanning type of a conventional example 1 conducts monofocal detection, and therefore scanning is required for wide range observation, thereby real time observation of fluorescence and others is difficult.  
      Since the multi-confocal microscope of a conventional example 2 detects a number of points simultaneously, the incident lights on neighboring foci mutually interfere. This is called a cross-talk. The incident light intensity distribution generated by said interference causes an interference pattern as bright and dark pattern. Because of this, the illuminated light intensity distribution becomes non-uniform, which causes a problem that the horizontal resolution of the observed image is lowered. Further, as an application of the confocal microscope, the largely dispersed fluoroescent signals from DNA chips cannot be observed on a detector at one time.  
      The multi-confocal microscope of a conventional example 3 conducts scanning by opening and closing in turn a number of points of a liquid crystal cell, and hence such a mechanical scanning system of a conventional example 2 is not necessary. However, since X-Y scanning for the number of pixels is required for turning on and off each pixel of a liquid crystal, scanning over one image takes time, and it is difficult to detect fluorescence and the like of whole of the sample in real time.  
      The DNA inspection apparatus discosed in JP 2001-108684A mentioned above makes the incident lights from a multi-spot array mutually interfere to cause cross-talk, and, like the confocal microscope of a conventional example 2, the illuminated light intensity distribution becomes non-uniform, thereby the horizontal resolution of the observed image is lowered.  
      Further, the DNA inspection apparatus disclosed in JP 2001-208688A mentioned above forms a multi-spot array using polarizer device, and, like the confocal microscope of a conventional example 1, makes observation by scanning in-plane on the sample stage. Although the time for scanning is made shorter than the case of monofocus of the multi-confocal microscope of a conventional example 1, the scanning is necessary to observe wide range, thereby a real time observation of fluorescence or the like is difficult.  
     DISCLOSURE OF THE INVENTION  
      The object of the present invention is, referring to the above-mentioned problems, to offer a confocal microscope using liquid crystal device, the method of fluorescent measurement of microarray substrates by the confocal microscopy using liquid crystal device, and to a method of polarized light measurement by the confocal microscopy using liquid crystal device, which are of high sensitivity, excel in resolution in the horizontal and the depth directions, and are capable of dynamic observation in a wide range.  
      In order to solve the problems mentioned above, a confocal microscope using liquid crystal in accordance with the present invention is a confocal microscope comprising: an inlet optical part to let a polarized light from an illuminating light source onto an object to be observed via a beam splitter, a matrix type liquid crystal device provided with a microlens array on its top part, and an objective lens; a light detecting part including an imaging device to detect a reflected or a fluorescent light from the object to be observed via said beam splitter and lens; and a control part including a liquid crystal control subpart to control each pixel of said matrix type liquid crystal device, characterized in that it transmits the light passing through said microlens array from each microlens to each pixel of said matrix type liquid crystal device, and makes a plurality of foci on said object to be observed by said objective lens, as well as controls the polarization direction of the light transmitted through each pixel of said matrix type liquid crystal device using said liquid crystal control subpart, and said liquid crystal control subpart controls polarization directions of the lights transmitted through each pixel of the matrix type liquid crystal device so that they are made mutually orthogonal.  
      In the above-mentioned aspect, a polarizer is preferably located under the matrix type liquid crystal device, and the polarization of light transmitted through a polarizer is preferably controlled by each pixel of the matrix type liquid crystal. According to said aspect, the light illuminated on the object to be observed is let in by a microlens array with each pixel of a matrix type liquid crystal device as a pinhole, and makes the first plurality of foci on the object to be observed. Further, since the reflected or fluorescent light from the object to be observed forms the second plurality of foci in the light detecting part, the microscope of the present invention works as a confocal microscope. In this case, as for each pixel of a matrix type liquid crystal device, each pixel of a matrix type liquid crystal device is controlled so that the polarization directions of the light transmitted through each pixel are made mutually orthogonal. Thus, observation of the reflected or fluorescent light from the object to be observed can be made at high speed without scanning control of said object. Also, the cross-talk between multi-confoci can be prevented, so that the resolution is improved.  
      Also, a confocal microscope using liquid crystal in accordance with the present invention is comprising: a inlet optical part to let a polarized light from an illuminating light source and a polarizer onto an object to be observed via a beam splitter, a lens, and the first matrix type liquid crystal device provided with a first microlens array on its top part, a light detecting part including an imaging device to detect a reflected or a fluorescent light from an object to be observed via a beam splitter, a lens, and a second matrix type liquid crystal device provided with a second microlens array on its top part; and a control part including a first and a second liquid crystal control subpart to control a polarization direction of a light transmitted through each pixel of said first and second matrix type liquid crystal device, characterized in that it transmits the light passing through said first microlens array from each microlens to each pixel of said first matrix type liquid crystal device aligned in the position corresponding to each microlens, and makes a plurality of foci on said object to be observed, and further, it transmits said reflected or fluorescent light passing through said second microlens array from each microlens array to each pixel of said second matrix type liquid crystal device aligned in the position corresponding to each microlens, and makes a plurality of foci on said imaging device, as well as controls the polarization direction of the light transmitted through each pixel of the first matrix type liquid crystal device using the first liquid crystal control subpart, and the first liquid crystal control subpart controls polarization directions of the lights transmitted through each neighboring pixel of the first matrix type liquid crystal device to be mutually orthogonal, thereby making a plurality of foci with the lights the polarization directions of which are mutually orthogonal onto an object to be observed, and controls the polarization direction of the light transmitted through each pixel of the second matrix type liquid crystal device using the second liquid crystal control subpart, and the second liquid crystal control part controls polarization directions of the lights transmitted through each neighboring pixel of the second matrix type liquid crystal device to be mutually orthogonal, thereby making a plurality of foci with the lights the polarization directions of which are mutually orthogonal onto an imaging device.  
      In the aspect mentioned above, a polarizer may be located under the first matrix type liquid crystal device, and the direction of polarized light passing through said polarizer may be controlled by each pixel of the first matrix type liquid crystal.  
      According to said aspect, the incident light illuminated on the object to be observed is let in by the first microlens array to each pixel of the first matrix type liquid crystal device, and makes the first plurality of foci on the object to be observed. Further, since the reflected or fluorescent light from the object to be observed passes through the second microlens array of the light detecting part and each pixel of the second matrix type liquid crystal device, and forms the second plurality of foci in the light detecting part, the microscope of the present invention works as a confocal microscope. In this case, as for each pixel of the first and the second matrix type liquid crystal devices, each pixel of a matrix type liquid crystal device is controlled so that the polarization directions of the light transmitted through each pixel are made mutually orthogonal. Thus, observation of the reflected or fluorescent light from the object to be observed can be made at high speed without scan control of said object. Also, the cross-talk between multi-confoci can be prevented, so that the resolution in the horizontal and the depth directions is improved. Further, by combination of the first and the second matrix type liquid crystal devices, polarization control, choice of detected signals, and others can be dynamically realized.  
      Also, a confocal microscope using liquid crystal in accordance with the present invention is comprising: an inlet optical part to let an amplitude modulated polarized light from an illuminating light source onto an object to be observed via a beam splitter, a matrix type liquid crystal device provided with a microlens array on its top part, and an objective lens; a light detecting part including an imaging device to detect a reflected or an fluorescent light from the object to be observed via said beam splitter and a lens; and a control part including a liquid crystal control subpart to control each pixel of said matrix type liquid crystal device, and an amplitude modulation control part of said illuminating light source, characterized in that it transmits the light passing through said microlens array from each microlens to each pixel of said matrix type liquid crystal device, and makes a plurality of foci said object to be observed by said objective lens, as well as it controls the polarization directions of the lights transmitted through each pixel of said matrix type liquid crystal device so that they are made mutually orthogonal by using said liquid crystal control subpart, and detects amplitude modulation signals of the reflected or fluorescent light from said object to be observed by transforming them to frequency component signals.  
      In the aspect mentioned above, a polarizer is preferably located under a matrix type liquid crystal device, and the polarized light transmitted through said polarizer is controlled by each pixel of the matrix type liquid crystal. Also preferably, the illuminating light source is either single wavelength or multi wavelengths, and the amplitude modulation of the illuminating light source is conducted using either of a matrix type liquid crystal device, an acoustooptic modulator, or a digital mirror device. Also, the amplitude modulation per one wavelength of the illuminating light source may be applied onto each pixel by a plurality of modulated frequency. Also preferably, the conversion of amplitude modulation signals of the reflected or fluorescent light from said object to be observed to frequency signals is operation-processed by high speed Fourier transform.  
      According to said aspect, since the incident light illuminated on the object to be observed is further amplitude modulated, the reflected or fluorescent light from said object can be detected with high sensitivity by signal conversion of the reflected or fluorescent light from said object on the frequency axis. Also, in case that the illuminating light source is multi wavelengths, the reflected or fluorescent light from multi wavelengths can be measured with high sensitivity in short period.  
      Also, a confocal microscope using liquid crystal device in accordance with the present invention is comprising: an inlet optical part to let an amplitude modulated polarized light from an illuminating light source onto an object to be observed via a beam splitter, a lens, and a first matrix type liquid crystal device provided with a first microlens array on its top part, a light detecting part including an imaging device to detect a reflected or a fluorescent light from the object to be observed via a beam splitter, a lens, a second matrix type liquid crystal device provided with a second microlens array on its top part, and a condenser lens; and a control part including a first and a second liquid crystal control subpart to control a polarization direction of a light transmitted through each pixel of said first and second matrix type liquid crystal device, characterized in that it transmits the light passing through said first microlens array from each microlens to each pixel of said first matrix type liquid crystal device, and makes a plurality of foci on said object to be observed, and further, it transmits said reflected or fluorescent light passing through said second microlens array from each microlens array to each pixel of said second matrix type liquid crystal device, and makes a plurality of foci on said imaging device, as well as controls the polarization direction of the light transmitted through each pixel of said first and second matrix type liquid crystal devices using said first and second liquid crystal control subpart, and detects amplitude modulation signals of the reflected or fluorescent light from said object to be observed by converting them to frequency signals.  
      In the aspect mentioned above, the first liquid crystal control subpart of the inlet optical part preferably controls the polarization direction of the light transmitted through each pixel of the first matrix type liquid crystal device to be mutually orthogonal. Also preferably, the second liquid crystal control subpart of the light detecting part controls the polarization direction of the light transmitted through each pixel of the second matrix type liquid crystal device to be mutually orthogonal. Also, a polarizer may be located in the lower part of the first matrix type liquid crystal device, and the polarization of the light transmitted through said polarizer may be controlled by each pixel of the matrix type liquid crystal. Preferably, the illuminating light source is either mono wavelength or multi wavelengths, and the amplitude modulation of said illuminating light source is conducted using either of a matrix type liquid crystal device, an acoustooptic modulator, or a digital mirror device. Also, the amplitude modulation per one wavelength of the illuminating light source may be applied on to each pixel by a plurality of modulation frequency. Also preferably, the conversion from amplitude modulation signal to the frequency signal of the reflected or the fluorescent light from an object to be observed is processed by Fast Fourier Transform.  
      According to said aspect, since the incident light illuminated on to the object to be observed is further amplitude modulated, the reflected or fluorescent light from said object can be detected with high sensitivity by signal conversion of the reflected or fluorescent light from said object on the frequency axis. Also, in case that the illuminating light source is multi wavelengths, the reflected or fluorescent light from multi wavelengths can be measured with high sensitivity in short period.  
      The measurement method of the fluorescence from a microarray substrate by the confocal microscope using the liquid crystal of the present invention in characterized to use a microarray substrate on which a fluorescent material to be a selective marker is applied in advance, and to observe the fluorescence from said fluorescent material by the confocal microscope of the present invention. In the aspect mentioned above, the microarray substrate is the object to be observed containing a minute amount of DNA or a biological material set in array on a plane. The microarray substrate may otherwise be a DNA chip. According to said aspect, by a confocal microscope using the liquid crystal of the present invention, the fluorescence can be efficiently observed without scanning on a microarray substrate.  
      Also, the measurement method of the polarized light of an object to be observed by a confocal microscope using the liquid crystal of the present invention is characterized to measure the polarized light from the reflected or the fluorescent light of said object by the confocal microscope of the present invention. Preferably, the polarized light from the object to be observed is measured by rotating said polarized light by 180 degrees in the liquid crystal matrix of a confocal microscope using liquid crystal. According to said aspect by the confocal microscope using liquid crystal of the present invention, the polarized light from the reflected or fluorescent light of the object to be observed can be efficiently observed.  
      By the confocal microscope using liquid crystal of the present invention, objects to be observed can be simultaneously measured without scanning of said object, owing to the use of matrix type liquid crystal device. And the cross-talk can be reduced by the polarized light control of each pixel of the matrix type liquid crystal device, and the resolution in the horizontal and the depth directions can be improved. Also in case that amplitude modulation is applied with the illuminating light source as mono wavelength or multi wavelengths, the reflected or the fluorescent light can be detected with high sensitivity.  
      By the measurement method of a microarray substrate using a confocal microscope of the present invention, the fluorescence of mono wavelength or multi wavelengths can be efficiently observed without mechanical scanning of a microarray substrate. Also, by the measurement method of the polarized light by a confocal microscope using liquid crystal of the present invention, the polarized light from an object to be observed can be efficiently observed using mono wavelength or multi wavelengths without mechanical scanning of the object to be observed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The present invention will better be understood from the following detailed description and the drawings attached hereto showing certain illustrative forms of embodiment of the present invention. In this connection, it should be noted that such forms of embodiment illustrated in the accompanying drawings hereof are intended in no way to specify or limit the present invention but to facilitate an explanation and an understanding thereof, in which drawings:  
       FIG. 1  is a diagrammatic view illustrating the makeup of a confocal microscope using liquid crystal in accordance with the first embodiment of the present invention;  
       FIG. 2  is a view diagrammatically illustrating the polarized light control of each pixel of a matrix type liquid crystal device;  
       FIG. 3  is a view illustrating the state of the polarized light transmitted through each pixel of a matrix type liquid crystal device of  FIG. 2 ;  
       FIG. 4  is a view illustrating another makeup of a confocal microscope in accordance with the first embodiment of the present invention;  
       FIG. 5  is a view briefly illustrating the functional effect of a polarizer provided to the inlet optical part;  
       FIG. 6  is a diagrammatic view illustrating the makeup of a confocal microscope in accordance with the second embodiment of the present invention;  
       FIG. 7  is a view illustrating another makeup of a confocal microscope in accordance with the present invention;  
       FIG. 8  is a diagrammatic view illustrating the makeup of a confocal microscope in accordance with the third embodiment of the present invention;  
       FIG. 9  is a diagrammatic view illustrating another example of the makeup of an illuminating optical part of a confocal microscope in accordance with the third embodiment of the present invention;  
       FIG. 10  is a diagrammatic view illustrating another makeup of a confocal microscope in accordance with the third embodiment of the present invention;  
       FIG. 11  is a diagrammatic view illustrating the makeup of a confocal microscope in accordance with the fourth embodiment of the present invention;  
       FIG. 12  is a diagrammatic view illustrating an example of the makeup of an illuminating optical part of a confocal microscope in accordance with the fourth embodiment of the present invention;  
       FIG. 13  is a diagrammatic view illustrating another makeup of a confocal microscope in accordance with the fourth embodiment of the present invention;  
       FIG. 14  is a diagrammatic view illustrating the makeup of a confocal microscope in accordance with the fifth embodiment of the present invention;  
       FIG. 15  is a diagrammatic view illustrating another example of the makeup of an illuminating optical part of a confocal microscope in accordance with the fifth embodiment of the present invention;  
       FIG. 16  is a view illustrating another makeup of a confocal microscope in accordance with the present invention;  
       FIG. 17  is a diagrammatic view illustrating the makeup of a confocal microscope in accordance with the sixth embodiment of the present invention  
       FIG. 18  is a view illustrating another makeup of a confocal microscope in accordance with the present invention;  
       FIG. 19  is a view illustrating the makeup of a confocal microscope of Conventional Example 1;  
       FIG. 20  is a view illustrating the principle of the scanning part of a multi-confocal microscope using Nipkow disc of Conventional Example 2; and  
       FIG. 21  is a view illustrating the makeup of a multi-confocal microscope of Conventional Example 3. 
    
    
     BEST MODES FOR CARRYING OUT THE INVENTION  
      Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawing figures. First of all, the first embodiment of a confocal microscope using liquid crystal device of the present invention is shown.  FIG. 1  is a diagrammatic view illustrating the makeup of a confocal microscope using liquid crystal in accordance with the first embodiment of the present invention. A confocal microscope using liquid crystal device  1  comprises an illuminating optical part  10 , an inlet optical part  20  which includes matrix type liquid crystal device and makes multi-foci on an object to be observed, a light detecting part  30  to detect the reflected light from the illuminated object to be observed, a control part  50  to control image data from the matrix type liquid crystal device and a light detecting part, and a stage  3  on which the object to be observed  2  is put.  
      The illuminating optical part  10  comprises an illuminating light source  11 , a collimater  12 , a first polarizer  13 , and a beam splitter  14 . The illuminating light source  11  is, for example, a laser source, and the outlet light is expanded to parallel light of a desired beam diameter by the collimater  12  made up with a lenses  12   a  and  12   b , and is let into the beam splitter  14  via the polarizer  13 . The wavelength of the laser source may be about 400 to 700 nm. Here, if a laser source of straight polarization is used as the illuminating light source  11 , the polarizer  13  may be omitted.  
      The inlet optical part  20  comprises, in order from above, a microlens array  21 , a matrix type liquid crystal device  22 , and an objective lens  23 . The parallel light let into the beam splitter  14  is reflected downward, and the light having uniform intensity distribution is focused on each pixel of the matrix type liquid crystal device  22  by the microlens array  21  located under the beam splitter  14 .  
      Said microlens array  21  is made up with a plurality of microlenses alighned array-like at the position corresponding to each pixel  22   a  of a matrix type liquid crystal device  22 , and can let in the light efficiently to each pixel  22   a  of a matrix type liquid crystal device  22 . Each incident light to the microlens array  21  passes through each pixel  22   a  of a matrix type liquid crystal device  22  as a pinhole. Each light thus passing through said each pixel  22   a  as a pinhole is once expanded, and makes an image as a plurality of foci  24  on the surface of the object to be observed  2  by the objective lens  23 .  
      The object to be observed  2  is set on the stage  3 . The stage  3  comprises an XYZ stage  3   a  movable forth and back and left and right and up and down, and a θ stage  3   b . By the stage  3  moved and adjusted by the XYZ stage  3   a  both horizontally and vertically, the position of the object to be observed  2  can be adjusted. At the same time, by the angle adjustment in XYZ plane by the θ stage  3   b , the position of the object to be observed  2  can also be adjusted.  
      The light detecting part to detect the reflected light from the object to be observed is explained. In the light detecting part  30 , the reflected light from the object to be observed  2  proceeds reversely on the incident light path to an imaging lens  31  via the beam splitter  14 , a plurality of foci  32  are formed on an imaging device  33 , and the image is made of the reflected light from the object to be observed  2 . As the imaging device  33 , CCD type or MOS type imaging devices can be used which can detect the above-mentioned images simultaneously. Further, said imaging device  33  may be cooled by a cooling apparatus using, for example, liquid nitrogen or the Peltier device so as to reduce noise to improve S/N ratio (signal-to-noise ratio).  
      Here, the reflected light from the object to be observed is in case of ordinary reflected light of the same wavelength from the illuminating light source  11  and in case of fluorescence from the object to be observed excited by the illuminating light source  11 . The wavelength of fluorescence is longer, in general, than that of the illuminating light source. Therefore, in case of fluorescence observation, a dichroic mirror or others may be used as a beam splitter  14  which can separate the wavelengths of the illuminating light source and fluorescence.  
      The control part  50  is provided with a personal computer  51 , a first liquid crystal control subpart  52 , and an image processing device  53 . Said personal computer  51  is provided with a display device  54  to display the images of the object to be observed and others.  
      Further, said personal computer  51  outputs the data to control the direction of polarized light passing through each pixel of the matrix type liquid crystal device  22  to the liquid crystal control subpart  52 . Said liquid crystal control subpart  52  is a drive circuit to convert the direction of rotated polarized light to a liquid crystal device drive signal by each pixel  22   a  of the matrix type liquid crystal device  22 . Said drive circuit converts the polarized light signal of each pixel  22   a  of the matrix type liquid crystal device  22  from the personal computer  51  to the liquid crystal drive signal suitable to a matrix type liquid crystal device  22 , that is, the voltage signal about each pixel  22   a . And the liquid crystal control subpart  52  controls the direction of polarized light passing through each pixel  22   a  by appropriately adjusting the drive voltage applied to each pixel  22   a , or by changing the drive voltage during the drive time. The image signal  33   a  of the imaging device  33  is output to the image processing device  53  of the control part  50 , the image data is processed by the personal computer  51 , and the image is output to the display device  54 .  
      Next, a polarization control of the matrix type liquid crystal device is explained. Each pixel  22   a  of the matrix type liquid crystal device  22  controls the direction of polarized light passing through each pixel  22   a  of the matrix type liquid crystal device  22  by the first liquid crystal control subpart  51  constituting the control part  50 . Thereby, the directions of inlet polarized light to each neighboring pixel are controlled to be mutually orthogonal. In this case, since all the pixels of the matrix type liquid crystal device are controlled simultaneously and for the time required for observation of the object  2 , the plurality of foci  24  can be formed simultaneously on the object to be observed.  
       FIGS. 2 and 3  are the views diagrammatically illustrating the polarized light control of each pixel of the matrix type liquid crystal device. As is shown in  FIG. 2 , the parallel light  15  from the collimater  12  is let into the matrix type liquid crystal device  22  via the first polarizer  13  and a microlens array  21 . The first polarizer  13  mentioned above is made by known art, and, for example, by sandwitching the polarization film between two plates of glass.  
      The incident parallel light becomes illuminating polarized light  16  in the direction of an arrow mark as shown in  FIG. 2  by the first polarizer  13 , and the incident polarized light  16  is controlled by each pixel  22   a  of a matrix type liquid crystal device as  17   a ,  17   b , and  17   c . Here, the polarized lights  17   a ,  17   b , and  17   c  of the polarized light  17  by a matrix type liquid crystal device show the vertical, the parallel, and the intermediate of vertical and parallel states to the illuminating polarized light  16 , respectively.  
       FIG. 3  shows the polarized state of the transmitted light through each pixel  22   a  in a matrix type liquid crystal device  22 . In the figure, a and b are the states of polarized light parallel and vertical to the incident light. Therefore, in case in the figure, the directions of polarized lights passing through each neighboring pixel  22   a  are mutually orthogonal. Thus, by controlling the directions of polarized lights passing through each neighboring pixel  22   a  of a matrix type liquid crystal device  22 , the incident lights of mutually neighboring a and b have orthogonal vibration components and cause no interference.  
      Here, the interfering each other are the pixels between a and a, or between b and b positioned at opposing corners. Since the distance of foci at between a and a or between b and b positioned at opposing corners is expanded to 2 1/2  compared with that between the neighboring foci a and b, the distance of neighboring foci can be made shorter to 0.71 (that is 2 −1/2 ) time compared to the case where the neighboring polarized incident light is not controlled. Therefore, the horizontal resolution can be improved by about 30% compared to the conventional case. Thereby, since the directions of polarized lights collected to the neighboring foci are mutually orthogonal by using the matrix type liquid crystal, the neighboring illuminating lights do not interfere each other, and the lowering of horizontal resolution by cross-talk can be prevented.  
      Next, the function of the confocal microscope using liquid crystal of the present invention is explained. The light illuminated onto an object to be observed is incident through each pixel  22   a  of the matrix type liquid crystal device  22  as a pinhole, and forms the plurality of the first foci  24  on said object. Further, since the reflected or fluorescent light from the object to be observed  2  forms the plurality of the second foci  32  on the light detecting part  30 , the microscope of the present invention works as the confocal microscope. In this case, with respect to each pixel  22   a  of the matrix type liquid crystal device  22 , each pixel  22   a  of the matrix type liquid crystal device can be controlled so that the directions of polarized light passing through each pixel  22   a  are made mutually orthogonal. Thereby, the cross-talks between multi-confoci are prevented, and the resolutions in horizontal and depth directions are improved. Also, the measurement of the reflected or fluorescent lights from the object to be observed  2  can be conducted at high speed without mechanical scanning of said object  2 .  
      Strictly speaking here, since an image can not be obtained for the pitch as an interval between each pixel  22   a  of a matrix type liquid crystal device  22 , an image may be made by moving the stage  3  by 1 pitch in the directions of X and Y.  
      Next, a modified example of the first embodiment of the confocal microscope using liquid crystal of the present invention is shown.  FIG. 4  is a view illustrating another makeup of a confocal microscope using liquid crystal in accordance with the present invention. The difference of a confocal microscope  1 ′ shown in  FIG. 4  from a confocal microscope  1  using liquid crystal shown in  FIG. 1  is an inlet optical part  20 . Other illuminating optical part  10 , the light detecting part  30 , the control part  50 , and the stage  3  are all same as in  FIG. 1 , so that explanation is skipped. The inlet optical part  20  differs from that in  FIG. 1  in that a second polarizer  25  is set in the lower part of the matrix type liquid crystal device  22 .  
       FIG. 5  is a view briefly illustrating the functional effect of a polarizer  25  provided to the inlet optical part. As shown in  FIG. 5 , the parallel light  15  from the collimater  12  is illuminated after passing through the first polarizer  13 , the microlens array  21 , and the matrix type liquid crystal device  22 . Here, said first and second polarizers  13 , 15  are not in co-axial, but are located to be mutually orthogonal (90 degrees). When the drive voltage is not applied to the pixel  22   a  of the matrix type liquid crystal device, the light transmitted through the first polarizer  13  passes through a pixel  22   a , and its polarization direction is twisted by 90 degrees as shown by  17 . Then it is transmitted through the second polarizer  25  the transmittance axis of which is twisted by 90 degrees with respect to the first polarizer  13 , and becomes transmitted light  26   a.    
      On the other hand, if the drive voltage is applied to the pixel  22   a , since the twisting state of a liquid crystal molecule in the pixel  22   a  changes depending upon the voltage, the direction of straight polarization transmitted through the first polarizer  13  can be rotated in said pixel  22   a  within the range of 0-90 degrees. Thereby, the intensity of the light transmitted through the second polarizer  25  can be controlled arbitrarily. Therefore, since the incident light is controlled by drive voltage of each pixel  22   a  of the matrix type liquid crystal device  22  so as to be transmittance  26   a , untransmitted shielded light  26   b , and their intermediate state (gray)  26   c , the illumination intensity can be changed.  
      The feature of the function of a confocal microscope using liquid crystal of the present invention is explained here. In this example, the illuminated light intensity can be controlled by use of the additional second polarizer  25 . Thereby, by controlling each pixel  22   a  of the matrix type liquid crystal device depending upon the object to be observed, the illuminated light intensity can be controlled.  
      The second embodiment of a confocal microscope using liquid crystal of the present invention is shown next.  FIG. 6  is a diagrammatic view illustrating the makeup of a confocal microscope using liquid crystal in accordance with the second embodiment of the present invention. In this figure, the confocal microscope  5  using liquid crystal comprises an illuminating optical part  10 , an inlet optical part  20 ′ including a matrix type liquid crystal device, and forming multi-focus on an object to be observed  2 , a light detecting part  30 ′ to detect the reflected light from said object, a control part  50 ′ to control the image data from the matrix type liquid crystal device and the light detecting part, and a stage  3  to set said object  2 . Here, the same makeup elements as in  FIG. 1  are marked with the same reference numerals, and the explanation is omitted. The illuminating optical part  10  comprises, as that in  FIG. 1 , the illuminating light source  11 , the collimater  12 , and the first polarizer  13 , and lets the polarized parallel light into the beam splitter  14 .  
      The inlet optical part  20 ′ comprises an objective lens  26 , a lens  27 , a microlens array  21 , and a matrix type liquid crystal device  22 . The polarized parallel light from the beam splitter  14  is further expanded by use of the objective lens  26  and the lens  27 . This expanded light with uniform intensity distribution is illuminated over whole the first microlens array  21 . The light from each microlens transmitted through the first microlens array  21  located on the surface of the first matrix type liquid crystal device  22  is transmitted through each pixel  22   a  of the first matrix type liquid crystal device  22 , and forms a plurality of focus  24  on the object to be observed  2  located on the stage  3 .  
      Each pixel  22   a  of the matrix type liquid crystal device  22  controls, as explained in  FIGS. 2 and 3 , so that the polarization directions of neighboring pixels of each pixel  22   a  of the first matrix type liquid crystal device  22  become mutually orthogonal by the first liquid crystal control subpart  51  making up the control part  50 ′. Thereby, since the polarization directions of the incident light collected on the neighboring foci are made mutually orthogonal by using the first matrix type liquid crystal device  22 , the neighboring incident lights do not interfere with each other, and lowering of the horizontal resolution by cross-talk can be prevented.  
      Next, the light detecting part  30 ′ to detect the reflected or fluorescent light from the object to be observed  2  after transmitting the beam splitter  14  will be explained. The light detecting part  30 ′ comprises a mirror  34 , a filter  35 , an objective lens  36 , a lens  37 , a second microlens array  38 , a second matrix type liquid crystal device  39 , a condenser lens  40 , and an imaging device  33 . Here, the optical part from the objective lens  36  to the second matrix type liquid crystal device  39  has the same makeup as the inlet optical part  20 ′ from the objective lens  26  to the first matrix type liquid crystal device  22 . The mirror  34  bends the light path of the reflected light from the object to be observed transmitted through the beam splitter  14  by 90 degrees, and lets it into the objective lens  36  via the filter  35  which transmits the light of specific wavelength only.  
      In order to observe fluorescence from an object to be observed  2 , since the fluorescent wavelength is longer than that from the illuminating light source  11 , a dichroic mirror may be used as a beam splitter  14  to transmit fluorescence only to the light detecting part  30 ′. Further for improvement of the contrast of fluorescence, an emission filter that transmits fluorescence only is preferably used as the filter  35 .  
      Next, the objective lens  36  and the lens  37  further expand the reflected or fluorescent light from an object to be observed  2 , and this light with uniform intensity distribution is illuminated onto whole the second microlens array  38 . Said second microlens array  38  comprises, like the first microlens array  21 , the microlenses aligned array-wise in the position corresponding to each pixel of the second matrix type liquid crystal device  39 , and can let in the light efficiently to each pixel of the second matrix type liquid crystal device  39 . The light from each microlens transmitted through the second microlens array  38  located on the surface of the second matrix type liquid crystal device  39  is transmitted through each pixel of a second matrix type liquid crystal device  39 , and forms a plurality of foci  41  on the imaging device  33  by the condenser lens  40 .  
      The control part  50 ′ has the same makeup as that  50  in  FIG. 1  except that a second liquid crystal control subpart  55  is provided as the control part of the second matrix type liquid crystal device  39  of the light detecting part  30 ′. The matrix type liquid crystal device  22  of the inlet optical part is controlled, as explained in  FIGS. 2 and 3 , by the first liquid control part  52  which makes up a control part  50 ′ so as to make the polarization directions of the light transmitted through neighboring pixels of each pixel  22   a  of the matrix type liquid crystal device  22  mutually orthogonal.  
      With respect to the incident reflected or fluorescent light to the light detecting part  30 ′, when its polarization is in the same direction so that the influence of interference is generated, the polarization directions of the reflected or fluorescent light may be set mutually orthogonal upon transmittance through the second matrix type liquid crystal device  39  of the light detecting part. Thereby, the mutually neighboring reflected or fluorescent lights to the imaging device do not interfere with each other, and lowering of the horizontal resolution by cross-talk can be prevented.  
      The direction of polarization of the reflected light transmitted through the pixel of the second matrix type liquid crystal device  39  in the light detecting part  30 ′ can be also controlled. In this case, since each pixel of the matrix type liquid crystal device  39  of the light detecting part  30 ′ can be controlled to the states of transmittance, shielding, or their intermediate, the visual field can be limited.  
      Here, the function of a confocal microscope using liquid crystal of the present invention is explained. The light illuminating the object to be observed  2  is illuminated into each pixel  22   a  of the first matrix type liquid crystal device by the first microlens array  21 , and forms a plurality of the first foci  24  on said object  2 . Further, since the reflected or fluorescent light from the object to be observed  2  forms a plurality of the second foci  41  by using the second microlens array  38  and each pixel of the second matrix type liquid crystal device  39  in the light detecting part  30 ′, the microscope of the present invention functions as the confocal microscope. In this case, each pixel of matrix type liquid crystal devices  22  and  39  can be controlled so that the polarization directions of the light transmitted through each pixel of matrix type liquid crystal devices  22  and  39  are set mutually orthogonal.  
      Therefore, unlike the conventional example 1 described above, it is not necessary to measure and synthesize images in time series by scanning a sample under the pinholes so separated that the cross-talk is not generated. Also unlike the conventional example 2, it is not necessary to measure and synthesize images in time series for each pair of the pinholes so separated that the cross-talk is not caused. Consequently, by the confocal microscope using liquid crystal device of the present invention, even if an image is formed with all pixels of a matrix type liquid crystal device as pinholes, no disturbance of images by cross-talk is generated, and all images of the object to be observed can be measured in real time. Thereby, the reflected or fluorescent light from said object can be measured at high speed without mechanical scanning control of said object  2 . Also, since the cross-talk can be prevented between multi-confoci, the resolution in the horizontal and the depth directions is improved. Also, the polarization control, selection of detected signals, and others can be realized by combination of the two matrix type liquid crystal devices.  
      A modified example of the second embodiment of the confocal microscope using liquid crystal of the present invention is shown next.  FIG. 7  is a view illustrating another makeup of a confocal microscope using liquid crystal in accordance with the present invention. The difference of the illustrated confocal microscope using liquid crystal device  5 ′ from that of  5  as shown in  FIG. 6  is an inlet optical part  20 ′. Since other illuminating optical part  10 , the light detecting part  30 ′, the control part  50 ′, and the stage  3  are same makeup as in  FIG. 6 , the explanation is omitted. In this example, the inlet optical part  20 ′ differs from that of  FIG. 6  in that the second polarizer  25  is located in the lower part of the matrix type liquid crystal device  22 .  
      The function of said second polarizer  25  is, as explained in  FIGS. 4 and 5 , to change the illuminating light intensity by drive voltage of pixels  22   a  of the first matrix type liquid crystal device. Each pixel of the first matrix type liquid crystal device  22  can be controlled so that the polarization directions of the light transmitted through each neighboring pixel  22   a  of the first matrix type liquid crystal device  22  of the incident optical part are set mutually orthogonal.  
      Here, the cross-talk between a plural of the foci  41  formed on the imaging device  33  by the reflected light from the object to be observed  2  can be prevented by polarization control of each pixel of the second matrix type liquid crystal device. Therefore, in case that the illumination of the incident light is controlled, since the image without cross-talk of the reflected light can be formed, it is not necessary to synthesize a whole image by mechanical scanning, unlike the conventional confocal microscope, and an immediate observation is possible by the display apparatus  54  of the control part  50 ′. Thereby, the reflected or fluorescent light from said object  2  can be observed at high speed without mechanical scanning of said object  2 . Also, the cross-talk can be prevented between multi-confoci, and the resolution is improved. Further, the illuminating light control, the polarization control, the selection of detected signals, and others can be realized by combination of two matrix type liquid crystal devices and the second polarizer  25 .  
      A third embodiment of a confocal microscope of the present invention is explained next.  FIG. 8  is a diagrammatic view illustrating the makeup of a confocal microscope using liquid crystal device in accordance with a third embodiment. The difference of a confocal microscope  7  shown in  FIG. 8  from that of  1  as shown in  FIG. 1  is an illuminating optical part  60  and a control part  70 . Since other inlet optical part  20 , the light detecting part  30  and the stage  3  are the same makeup as shown in  FIG. 1 , their explanation is omitted.  
      An illuminating optical part  60  differs from a confocal microscope using liquid crystal  1  of  FIG. 1  in that amplitude modulation can be applied to an illuminating light source  11 . The illuminating optical part  60  comprises an illuminating light source  11  and an amplitude modulation part  61 . The amplitude modulation part  61  generates an amplitude modulated beam light  62 . For the amplitude modulation of the illuminating light source  11 , an amplitude modulation device such as a matrix type liquid crystal device, an acoustooptic modulator, a digital mirror device, and others may be used.  
      The illuminating optical part  60  shown in  FIG. 8  uses a matrix type liquid crystal device as the amplitude modulation device, and it comprises an illuminating light source  11 , a collimater  12 , a third polarizer  63 , a matrix type liquid crystal device  64  for amplitude modulation, and a fourth polarizer  65 . The illuminating light source  11  uses, for example, a laser light source, and the output light is expanded to parallel light of the desired beam diameter by the collimater  12  made up with lenses  12   a  and  12   b . The locations of the third and the fourth polarizers  63  and  65  are such that they are mutually orthogonal, and the intensity of the expanded beam is modulated, so-called AM modulated (frequency f 1 ) by the voltage applied on to each pixel of the matrix type liquid crystal device  64  for amplitude modulation inserted between the third and the fourth polarizers  63  and  65 . The matrix type liquid crystal device  64  for amplitude modulation is controlled by a control part  70  as described below. In this case, as the amplitude modulation frequencies of neighboring pixels differ from each other, the amplitude modulation may be conducted by a plurality of different frequencies such as, for example, f 1  and f 2 . Such modulation frequencies are preferably selected so that they are not in higher harmonic relation with each other.  
       FIG. 9  is a diagrammatic view illustrating another example of the makeup of an illuminating optical part of a confocal microscope in accordance with the third embodiment of the present invention. A illuminating optical part  60 ′ differs from the illuminating optical part  60  of  FIG. 8  in that an acoustooptic modulator  68  is further provided between the illuminating light source  11  and the collimater  12 . After the illuminating light source  11  is amplitude modulated (modulation frequency f AO ) by the acoustooptic modulator  68 , and is expanded to parallel light of the desired beam diameter by the collimater  12 , the light amplitude is modulated (modulation frequency f 2 ), so-called double amplitude modulated, by the matrix type liquid crystal device  64  for amplitude modulation. The acoustooptic modulator  68  can be modulated with much higher frequency than that of using the matrix type liquid crystal device for amplitude modulation (f AO &gt;f 1 , f 2 ).  
      The control part  70  differs from that of  50  in the confocal microscope using liquid crystal of  FIG. 1  in that the amplitude modulated reflected light is detected. The control part  70  is provided with an amplitude modulation control part  56  and an image processing apparatus  58  to detect the amplitude modulated reflected light. The illuminating light source  11  is modulated by amplitude modulation devices  64  and  68  which are driven by the amplitude modulation control part  56 . The amplitude modulated incident light in the illuminating optical part  60  is illuminated onto an object to be observed  2  via an inlet optical part  20 , like the confocal microscope  1  shown in  FIG. 1 . The reflected light from said object is let into the light detecting part  30 , signal-processed in the image processing apparatus  58 , and its image signal is sent out to the personal computer  51 .  
      The image processing apparatus  58  is comprised an amplifier for the detected electrical signal, an A/D converter, and others, digitalizes the time axis signal from the light detecting part, and sends it out to the personal computer  51 . The personal computer  51  conducts the Fourier transform to transfer time axis signals to frequency component signals, obtains the amplitude distribution of the reflected or fluorescent light from the object to be observed  2 , and displays it on the display  54 . The Fourier transform can be calculated by the Fast Fourier Transform method.  
      The function of the confocal microscope  7  in accordance with the third embodiment is explained next. The function of the confocal microscope  7  in accordance with the third embodiment differs from that of the confocal microscope  1  in that the light illuminated onto an object to be observed  2  is amplitude modulated. In each pixel  22   a  of the matrix type liquid crystal device  22 , the light transmitted through each pixel  22   a  is amplitude modulated, as well as each pixel  22   a  of it is controlled so the polarization directions are made mutually orthogonal. The reflected or fluorescent light from said object  2  can be detected on the frequency axis by converting the amplitude modulated signal from each pixel to a frequency signal in the light detecting part  30  and the control part  70 . In this case, since the noise or others except for the cross-talk generated inside the confocal microscope  7  using liquid crystal device are different from the amplitude modulation frequency and can be easily distinguished on the frequency axis, the signal-to-noise ratio (S/N ratio) can be improved. That is, the reflected or fluorescent light from the object to be observed  2  can be detected with high sensitivity. Also in case that neighboring pixels are amplitude modulated with different frequency, the cross-talk can be further prevented. Thereby, since the cross-talk between multi-confoci can be prevented, as well as the reflected or fluorescent light intensity can be detected by the frequency of amplitude modulation, the sensitivity is made higher, and the resolutions in the horizontal and the depth directions are further improved than that of the confocal microscope  1 . Also, the reflected or fluorescent light from the object to be observed  2  can be measured with high speed.  
      Next, a modified example of a confocal microscope of the third embodiment mentioned above will be explained.  FIG. 10  is a diagrammatic view illustrating another makeup of a confocal microscope using liquid crystal in accordance with the third embodiment. The difference of a confocal microscope  7 ′ shown in  FIG. 10  from that of  7  using liquid crystal shown in  FIG. 8  is an inlet optical part  20 . Since other illuminating optical part  60 , the light detecting part  30 , the control part  70 , and the stage  3  are the same makeup as in  FIG. 8 , their explanation is omitted. The inlet optical part  20  differ from that of  FIG. 8  in that a second polarizer  25  is provided in the lower part of a matrix type liquid crystal device  22 . In this example, the intensity of illuminating light can be controlled, as explained in  FIG. 5 , by adding the second polarizer  25 . Thereby, the intensity of illuminating light can be controlled by the control of each pixel  22   a  of a matrix type liquid crystal device depending upon the object to be observed.  
      Next, the fourth embodiment of a confocal microscope of the present invention will be explained.  FIG. 11  is a diagrammatic view illustrating the makeup of a confocal microscope using liquid crystal in accordance with the fourth embodiment. The difference of a confocal microscope  8  shown in  FIG. 11  from that of  7  using liquid crystal shown in  FIG. 8  is an illuminating optical part  80  and the control part  90 . Since other inlet optical part  20 , the light detecting part  30  and the stage  3  are same makeup as in  FIG. 8 , their explanation is omitted. In the illuminating optical part  80 , the illuminating light source  11  comprises a light source having a plurality of wavelengths and an amplitude modulation part  82  to apply different amplitude modulation to a light source of each wavelength. In the figure, the illuminating light source  11  is explained as having light sources  11   a ,  11   b , and  11   c  of three different wavelengths. The amplitude modulation part  82  generates the beam light  84  to amplitude modulate the illuminating light source  11 . For the amplitude modulation of the illuminating light source  11 , such amplitude modulation devices as a matrix type liquid crystal device, an acoustooptic modulator, a digital mirror device, and others may be used. The control part  90  is provided with an amplitude modulation control part  91  of the illuminating light source, and an image processing apparatus to detect the amplitude modulated reflected or fluorescent light from an object to be observed  2 .  
       FIG. 12  is a diagrammatic view illustrating an example of the makeup of an illuminating optical part of a confocal microscope in accordance with the fourth embodiment mentioned above. In the illuminating optical part  80 , each of light sources  11   a ,  11   b , and  11   c  with three different wavelengths comprises collimaters  12   a ,  12   b , and  12   c , a third polarizers  63   a ,  63   b , and  63   c , matrix type liquid crystal devices for amplitude modulation  64   a ,  64   b , and  64   c , a fourth polarizers  66   a ,  66   b , and  66   c , and beam splitters  85 ,  86 , and  87 , respectively. For example, in the illuminating light source  11   a , the outlet light is expanded to parallel light of the desired beam diameter by a collimater  12  comprising lenses  12   a  and  12   b , similarly to the illuminating light source  11  explained in  FIG. 9 . The locations of the third and the fourth polarizers  62  and  66  are such that they are mutually orthogonal. The light amplitude of said expanded beam is modulated, so-called AM (frequency f 1 ) by the voltage applied onto each pixel of the matrix type liquid crystal device  64   a  for amplitude modulation inserted between the third and the fourth polarizers  62   a  and  66  to become the amplitude modulated beam  84   a.    
      The matrix type liquid crystal device  64   a  for amplitude modulation is controlled by the amplitude modulation control part  91  of the control part  90 . Also in the illuminating light sources  11   b  and  11   c  as in the illuminating light source  11   a , amplitude modulated beams  84   b  (frequency f 2 ) and  84   c  (frequency f 3 ) are formed by matrix type liquid crystal devices  64   b  and  64   c  for amplitude modulation. The amplitude modulation devices  64   a ,  64   b , and  64   c  are driven by the amplitude modulation control part  91  and the illuminating light sources  11   a ,  11   b , and  11   c  are amplitude modulated. The amplitude modulated beams  84   a ,  84   b , and  84   c  in the illuminating optical part  80  are let into beam splitters  85 ,  86 , and  87 , respectively, to become the amplitude modulated beam  84  by wave multiplexing. Here, as the amplitude modulation frequencies differ for the neighboring pixels, each pixel of the amplitude modulated beams  84   a ,  84   b , and  84   c  may be amplitude modulated with a plurality of different frequencies. For example, the amplitude modulation frequencies of the amplitude modulated beam  84   a  (wavelength λ 1 ) may be defined as f 1 , f 2 , and f 3  in the order of neighboring pixels, and, similarly the amplitude modulation frequencies of the amplitude modulated beam  84   b  (wavelength λ 2 ) may be defined as f 4 , f 5 , and f 6 , and the amplitude modulation frequencies of the amplitude modulated beam  84   c  (wavelength λ 3 ) may be defined as f 7 , f 8 , and f 9 . Such modulation frequencies are preferably selected so they are not in higher harmonic relation with each other.  
      Amplitude modulated beams  84  are illuminated onto an object to be observed  2  via an inlet optical part, like the confocal microscope  7  using liquid crystal as shown in  FIG. 8 . The reflected or fluorescent light from said object is let into the light detecting part  30 , signal-processed in the image processing apparatus  92 , and its image signal is sent out to the personal computer  51 . The image processing apparatus  92  is comprising an amplifier for the detected electrical signals, an A/D converter, and others, digitalizes the time axis signal from the light detecting part, and sends it out to the personal computer  51 . The personal computer  51  conducts Fourier transform to convert time axis signals to frequency component signals, obtains the intensity distribution of the reflected light, and displays it on the display  54 . The Fourier transform can be calculated by the Fast Fourier Transform method to shorten the processing time.  
      Next, a function of the confocal microscope  8  of the fourth embodiment mentioned above will be explained. The function of said confocal microscope  8  differ from that of the confocal microscope  7  in that a plurality of lights illuminated onto an object to be observed  2  are amplitude modulated. In each pixel  22   a  of the matrix type liquid crystal device  22 , the light transmitted through each pixel  22   a  is amplitude modulated, as well as each pixel  22   a  of it is controlled so the polarization directions are made mutually orthogonal. The reflected or fluorescent lights of a plurality of wavelengths from said object  2  can detect the amplitude modulated signal of each wavelength from each pixel on the frequency axis in the light detecting part  30  and the control part  90 . In this case, since the noise or others except for the cross-talk generated inside the confocal microscope  7  using liquid crystal device are different from the amplitude modulation frequency and can be easily distinguished on the frequency axis, the signal-to-noise ratio (S/N ratio) can be improved. That is, the reflected or fluorescent light from the object to be observed  2  can be detected with high sensitivity. Also in case that neighboring pixels are amplitude modulated with different frequency, the cross-talk can be further prevented. Thereby, since the cross-talk between multi-confoci can be prevented, as well as the reflected or fluorescent light intensity can be detected by the frequency of amplitude modulation. The sensitivity is made higher for multi wavelengths, and the resolutions in the horizontal and the depth directions from multi wavelengths are improved as the confocal microscope  7  could not attain. Also, the reflected or fluorescent light from the object to be observed  2  can be measured with high speed.  
      A modified example of the fourth embodiment of a confocal microscope is shown next.  FIG. 13  is a diagrammatic view illustrating another makeup of a confocal microscope using liquid crystal in accordance with the fourth embodiment. The difference of a confocal microscope  8 ′ shown in  FIG. 13  from that of  8  using liquid crystal shown in  FIG. 11  is an inlet optical part  20 . Since other illuminating optical part  80 , the light detecting part  30 , the control part  90 , and the stage  3  are the same makeup as in  FIG. 11 , their explanation is omitted. The inlet optical part  20  differs from that of  FIG. 11  in that a second polarizer  25  is provided to the lower part of a matrix type liquid crystal device  22 . In this modified example, the illuminating light intensity can be controlled, as explained in  FIG. 5 , by adding the second polarizer  25 . Thereby, the illuminating light intensity can be controlled by the control of each  22   a  of a matrix type liquid crystal device depending upon the object to be observed.  
      The fifth embodiment of a confocal microscope of the present invention is explained next.  FIG. 14  is a diagrammatic view illustrating the makeup of a confocal microscope using liquid crystal in accordance with the fifth embodiment. The difference of a confocal microscope  9  shown in  FIG. 14  from that of  5  using liquid crystal shown in  FIG. 6  is an illuminating optical part  60  and a control part  100 . Since other inlet optical part  20 ′, the light detecting part  30 ′ and the stage  3  are same makeup as in  FIG. 6 , their explanation is omitted. The illuminating optical part  60  is same as that  60  shown in  FIG. 8  comprising a light source  11  and an amplitude modulation part  62 , and generates the beam light  62  from the illuminating light source  11  which is amplitude modulated by a matrix type liquid crystal device  64  for amplitude modulation. The matrix type liquid crystal device  64  for amplitude modulation is controlled by the control part  100  described below. In this case, the amplitude modulation by a plurality of different frequencies is preferable so that the amplitude modulation frequencies of neighboring pixels differ.  
       FIG. 15  is a diagrammatic view illustrating another example of the makeup of an illuminating optical part of a confocal microscope in accordance with the fifth embodiment mentioned above. In said confocal microscope  9 A, an illuminating optical part  60  differs from that of  60  as shown in  FIG. 14  in that an acoustooptic modulator  68  is further provided between the illuminating light source  11  and a collimater  12 . After the illuminating light source  11  is amplitude modulated by the acoustooptic modulator  68 , and the light is expanded to parallel light of desired beam diameter by the collimater  12 , the light amplitude is modulated by the matrix type liquid crystal device  64  for amplitude modulation, that is, so-called double amplitude modulated. It can be modulated with more high frequency with use of the acoustooptic modulator  68  than that of the matrix type liquid crystal device for amplitude modulation.  
      The control part  100  differs from that of  50 ′ as shown in  FIG. 6  in that it is provided with an amplitude modulation control part  56  and an image processing apparatus  101  to detect the amplitude modulated reflected light. The amplitude modulation control part  56  drives an amplitude modulation device  64 , and amplitude modulates the illuminating light source  11 . The incident light which is amplitude modulated by the illuminating optical part  60  is illuminated onto an object to be observed  2  via the inlet optical part  20 ′, as in case of the confocal microscope  5  shown in  FIG. 6 . The reflected light from said object  2  is let into the light detecting part  30 ′, signal processed in the image processing apparatus  101 , and its image signal is sent out to the personal computer  51 .  
      The image processing apparatus  101  is comprising an amplifier for the detected electrical signals, an A/D converter, and others, digitalizes the time axis signal from the light detecting part, and sends it out to the personal computer  51 . The personal computer  51  conducts Fourier transform to transfer time axis signals to frequency component signals, obtains the amplitude distribution of the reflected or fluorescent light, and displays it on the display  54 . The Fourier transform can be calculated by the Fast Fourier Transform method to shorten the processing time.  
      An operation of the confocal microscope in accordance with the fifth embodiment is explained here. In the confocal microscope  9  of the fifth embodiment mentioned above, each pixel of matrix type liquid crystal devices  22  and  39  is controlled so that the polarization directions transmitted through each pixel of matrix type liquid crystal devices  22  and  39  are made mutually orthogonal, as explained in the operation of a confocal microscope  5  in accordance with the second embodiment.  
      According to the fifth embodiment, the reflected or fluorescent light from the object to be observed  2  can be detected by using the amplitude modulated signals of each pixel on the frequency axis in the light detecting part  30  and the control part  100 . In this case, since the noise or others except for the cross-talk generated inside the confocal microscope  7  using liquid crystal device are different from the amplitude modulation frequency and can be easily distinguished on the frequency axis, the signal-to-noise ratio (S/N ratio) can be improved. That is, the reflected or fluorescent light from the object to be observed  2  can be detected with high sensitivity. Also when neighboring pixels are amplitude modulated with different frequency, the cross-talk can be further prevented.  
      Next, a modified example of the fifth embodiment of a confocal microscope of the present invention is shown in  FIG. 16 . The difference of a confocal microscope  9 B using liquid crystal shown in the figure from that of  9  shown in  FIG. 14  is an inlet optical part  20 ′. Since other illuminating optical part  60 , the light detecting part  30 ′, the control part  100 , and the stage  3  are same makeup as in  FIG. 14 , their explanation is omitted. The inlet optical part  20 ′ of this example differs from that of  FIG. 14  in that a second polarizer  25  is provided to the lower part of the matrix type liquid crystal device  22 . The function of said second polarizer  25  is to change illuminating light intensity by drive-voltage of a pixel  22   a  of the first matrix type liquid crystal device, as explained in  FIGS. 4 and 5 . In each pixel  22   a  of the first matrix type liquid crystal device  22  of the inlet optical part, each pixel of the first matrix type liquid crystal device  22  can be controlled so that the polarization directions transmitted through each neighboring pixel  22   a  are made mutually orthogonal.  
      Next, the sixth embodiment of a confocal microscope of the present invention is shown in  FIG. 17 . The difference of a confocal microscope  9 C from that of  9  shown in  FIG. 14  is an illuminating optical part  80  and a control part  100 ′. Here, the explanation is omitted by marking with same reference numerals to the same makeup components of  FIG. 14 . Since the illuminating optical part  80  can be made up identically as in  FIGS. 11 and 12 , the detail explanation is omitted. Since also the control optical part  100 ′ can be made up identically as in  FIG. 14  except that it is comprising an amplitude modulation control part  56  and an image processing apparatus  101  to detect the amplitude modulated reflected light, the detail explanation is omitted.  
      Here, the illuminating light source  11  has the lights  11   a ,  11   b , and  11   c  of three different wavelengths, and each light of respective wavelength is amplitude modulated. For the light transmitted through each pixel of matrix type liquid crystal devices  22  and  39 , each pixel of matrix type liquid crystal devices  22  and  39  is controlled so that the polarization directions are made mutually orthogonal, and, since the reflected or fluorescent lights of different wavelengths are amplitude modulated in each pixel, the cross-talk is not occurred. Also, since the incident light of different wavelength has different amplitude modulation frequency in each pixel, the reflected or fluorescent light from respective wavelength can be easily distinguished.  
      Further, since the noise or others except for the cross-talk generated inside the confocal microscope  9  are different from the amplitude modulation frequency and can be easily distinguished on the frequency axis, the signal-to-noise ratio (S/N ratio) can be improved. That is, the reflected or fluorescent light from the object to be observed  2  can be detected with high sensitivity. Thereby, the reflected or fluorescent light having multi wavelengths of said object  2  can be observed at high speed and high sensitivity without mechanical scanning of said object  2  and switching of detectors depending upon wavelengths. Also, the cross-talk can be prevented between multi-confoci, and the resolution is improved.  
      Next, a modified example of the sixth embodiment of a confocal microscope is explained, referring to  FIG. 18 . The difference of a confocal microscope  9 D using liquid crystal shown in the figure from that of  9 C shown in  FIG. 17  is an inlet optical part  20 ′. Since other illuminating optical part  80 , the light detecting part  30 ′, the control part  100 ′, and the stage  3  are same makeup as in  FIG. 17 , their explanation is omitted. The inlet optical part  20 ′ of this example differs from that of  FIG. 17  in that a second polarizer  25  is provided to the lower part of a matrix type liquid crystal device  22 . The function of said second polarizer  25  is to change illuminating light intensity by drive-voltage of a pixel  22   a  of the first matrix type liquid crystal device as explained in  FIGS. 4 and 5 . In each pixel  22   a  of the first matrix type liquid crystal device  22  of the inlet optical part, each pixel of the first matrix type liquid crystal device  22  is controlled so that the polarization directions of the light transmitted through each neighboring pixel  22   a  are made mutually orthogonal.  
      Here, the cross-talks between plural foci  41  formed on the imaging device  33  by the reflected light from the object to be observed  2  can be prevented by polarization control of each pixel of the second matrix type liquid crystal device. Therefore, when the incident light illumination is controlled, since the image without cross-talks of the reflected light can be formed, it is not necessary to synthesize a whole image by mechanical scanning like a conventional confocal microscope, and immediate observation is possible on the display  54  of the control part  100 ′. Thereby, the reflected or fluorescent light having multi wavelengths of said object  2  can be measured with a high speed without using mechanical scanning of said object  2 . Also, cross-talks can be prevented between multi confoci, and the resolution is improved, as well as the sensitivity is improved by the amplitude modulated light source. Further by combination of two matrix type liquid crystal devices and the second polarizer  25 , the illuminating light control, the polarized light control, selection of detected signals, and others can be realized.  
      The embodiment of the method of measurement of a microarray substrate using a confocal microscope is explained below. Here, the microarray substrate is an object to be observed of a minute amount of the planarly located DNA, or a biological material. A fluorescent material is given in advance as a selective marker in said microarray substrate. Said microarray substrate may also be a DNA microarray substrate which is hybridization-reacted with a fluorescent-marked single chain DNA.  
      The measurement method to observe said DNA microarray substrate using a confocal microscope  5  of the present invention shown in  FIG. 6  is explained. The size of the first and second matrix type liquid crystal devices  22  and  39  in the confocal microscope  5  should be sufficiently larger than that of the DNA microarray substrate. Therefore, the whole reflected image or fluorescent light from the DNA microarray substrate can be observed using the confocal microscope  5 .  
      First, the DNA microarray substrate is located on the stage  3 , and the illuminating light source  11  is switched on. Next the Z-direction position of the DNA microarray substrate to be observed is adjusted using the XYZ stage  3   a  and the θ stage  3   b  so that the focus position of the illuminating light source  11  and the detection position of the DNA microarray substrate are overlapped.  
      The incident light to the DNA microarray substrate is controlled by the first liquid crystal control subpart  52  so that the polarization directions of the incident light transmitted through each neighboring pixel  22   a  are made mutually orthogonal by the matrix type liquid crystal device  22 . In this case, each pixel of the second matrix type liquid crystal device  39  in the light detecting part is also controlled by the second liquid crystal control subpart. Thus, all the fluorescence generated from the DNA microarray substrate can be simultaneously detected by using, for example, a CCD camera as the imaging device  33 , and the fluorescent image can be observed by changing the intensity of detected signals or polarization direction.  
      Here, the size of pixels of matrix type liquid crystal devices  22  and  39  is 10-20 μm, and since the diameter of single fluorescence generated from a DNA microarray substrate is, for example, about 100 μm, the resolution is sufficient. Therefore, the number of fluorescences or their positions of generation on the DNA microarray substrate can be immediately judged. And the image recording or data processing can be conducted rapidly by using the personal computer  51  of the control part  50 . Also, by observing said DNA microarray substrate by using the confocal microscope of the present invention shown in  FIG. 14 , the light source is amplitude modulated, and the fluorescence from said DNA microarray substrate can be measured with a high sensitivity on the frequency axis.  
      Next, the measurement method to observe a DNA microarray substrate by using the confocal microscope  5  of the present invention shown in  FIG. 11  is explained when a fluorescent material is given in advance which possesses a plurality of fluorescent wavelengths as selective markers. If the observation is made by using the confocal microscope  9 B of the present invention as shown in  FIG. 16 , then the light source has multi wavelengths, and each wavelength is amplitude modulated, so that the fluorescence of multi wavelengths from a DNA microarray substrate can be measured with a high sensitivity on the frequency axis.  
      According to the measurement method of the microarray substrate using the confocal microscope mentioned above, the multi foci corresponding to the number of pixels of thetrix type liquid crystal device are formed on the micorarray substrate, the reflected light from them are let into a confocal light detecting part via the operation optical part, and are formed as the multi foci corresponding to the number of pixels via a matrix type liquid crystal device. Consequently, by the confocal microscope of the present invention, the objects to be observed corresponding to the number of pixels of a matrix type liquid crystal device can be observed simultaneously. Also, since the light source of not only a single wavelength but also multi wavelengths can be used, the fluorescence of multi wavelengths from a DNA microarray substrate can be measured in a short time with high accuracy. Thereby, a sharp whole image of the ecxited fluorescence from the DNA microarray substrate can be observed without mechanical scanning of a DNA microarray substrate, that is, at ream time.  
      An embodiment of the measurement method of the polarized light using a confocal microscope is explained next. The polarized light is that from the reflected or fluorescent light of the object to be observed  2 , and for example, a case is explained as an example where the polarized light from the fluorescent light by said DNA microarray substrate, using a confocal microscope  9 C of the present invention shown in  FIG. 17 .  
      First of all, a DNA microarray substrate is set on a stage  3 , and an illuminating light source  11  is switched on. Next the Z-directional position of the DNA microarray substrate to be observed is adjusted by using an XYZ stage  3   a  and a θ stage  3   b  so that the focus position of the illuminating light source  11  and the detection position of the DNA microarray substrate are overlapped. The incident light into the DNA microarray substrate is controlled by the first liquid crystal control subpart  52  so that the polarization directions of the incident lights transmitted through neighboring pixels are made to differ from one another by the matrix type liquid crystal device  22 . In this case, the polarization direction of the light transmitted through each pixel can be controlled independently for each pixel. By rotating said polarized light to 180 degrees, the amount of light transmitted through a polarizer  25  is changed, and the change of the polarized light from the object to be observed can be observed.  
      Thus, the polarized light from fluorescent or reflected light of the DNA microarray substrate, biological samples, sugar-protein bonding, or the like can be detected by using, for example, a CCD camera as an imaging device  33 . When the observation is made by use of the confocal microscope  9 B of the present invention, then the light source has multi wavelengths, and each wavelength is amplitude modulated, so that the polarized light of fluorescence of multi wavelengths from a DNA microarray substrate can be measured with high sensitivity on the frequency axis.  
      Here, since the sizes of pixels of the matrix type liquid crystal devices  22  and  39  are 10-20 μm, and, for example, the size of single fluorescence generated on a DNA microarray substrate is about 100 μm in diameter, the resolution is sufficient. Therefore, the polarized light of fluorescence of the DNA microarray substrate can be measured immediately. In this case, recording of images and data processing can be performed with high speed by using the personal computer  51  in the control part  50 .  
      According to the measurement method of the polarized light of the reflected or fluorescent light using a confocal microscope of the present invention, the multi foci corresponding to the number of pixels of a matrix type liquid crystal device are formed on the micorarray substrate, the reflected light from them are let into a confocal light detecting part via a separation optical part, and are formed as the multi foci corresponding to the number of pixels via a matrix type liquid crystal device. Consequently, by the confocal microscope of the present invention, the polarized lights from the objects to be observed corresponding to the number of pixels of a matrix type liquid crystal device can be observed simultaneously. Also, since the light source of not only a single wavelength but also multi wavelengths can be used, the polarized light from the reflected or the fluorescent light of multi-wavelength from the object to be observed can be measured in a short time with high accuracy.  
      It is needless to mention that the present invention is not limited to the embodiments described above, but can be modified variously within the limitation of the invention as set forth in the claims, and said modifications are also included in the claims. An imaging device is used as a light detecting part in the embodiments mentioned above, but it is also possible to use a plurality of detective parts if necessary, so that the visual observation or the photography are possible at the position of an imaging device. Also it is needless to mention that, for the compositions of the inlet and the light detecting part of multi wavelengths and the amplitude modulation devices, optimal designs and the parts to use for them may be selected depending upon the object to be observed.