JP2004177732A - Optical measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical measuring device capable of effectively preventing monochrome light generated in a monochrome optical system and having high energy density from reaching the color imaging device of a white optical system without being accompanied with disadvantage in terms of spacing and the reduction of cost. <P>SOLUTION: The white optical system 3 includes a white light projecting system including a white light source 20 and lenses 21 and 22, a white light receiving system including the color imaging device 24 and a lens 23 and a filter half mirror 16 for separating the white light projecting system from the optical axis of an objective 17. A half mirror 15 for separating a part including the monochrome light source 10 and the photodetector 19 of the monochrome optical system 2 from the optical axis of the objective 17 is provided between the mirror 16 and the objective 17. Then, filter glass through which the monochrome light does not pass but most of the components of the white light passes is used as the base material of the mirror 16, so that the white light passing through the mirror 16 reaches the device 24. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a monochromatic optical system for irradiating a sample with monochromatic light from a monochromatic light source to receive monochromatic light from the sample with a light receiving element, and irradiating the sample with white light from a white light source to form a white light from the sample. The present invention relates to an objective lens and an optical measurement device having an optical axis common to a monochromatic optical system and a white optical system, the system including a white optical system for receiving light with a color image sensor.
[0002]
[Prior art]
As such an optical measuring device, there is a confocal microscope having a color imaging function. The confocal microscope scans the sample surface with monochromatic light while changing the distance between the focal point of the objective lens and the sample, and receives monochromatic light from the sample surface with a light receiving element via a confocal optical system (monochromatic optical system). Then, a height distribution of the sample surface obtained by processing the received light information, an ultra-deep image (an image having a very deep focal depth), and the like are displayed on the screen. When the distance between the focus of the objective lens and the sample is changed, the amount of light incident on the light receiving element via the confocal optical system, that is, the amount of received light changes, and the amount of received light is focused when the surface of the sample is focused. Will be the largest. Therefore, height information of each point on the sample surface is obtained from the distance between the focus of the objective lens and the sample when the maximum amount of received light is obtained.
[0003]
Also, while changing the distance between the focus of the objective lens and the sample at a predetermined pitch, the maximum amount of light received at each point on the sample surface (the amount of light received when the subject is in focus) is acquired, and the maximum amount of light received at each point is connected. This makes it possible to obtain a black-and-white image of the sample surface with a very deep depth of focus. This image is a super-depth image.
[0004]
Further, a confocal microscope (color confocal microscope) having a color image capturing function includes a confocal optical system (monochromatic optical system), a non-confocal optical system (white optical system) that shares an objective lens and its optical axis. Have. By receiving light from a sample irradiated with white light by a color imaging element via a non-confocal optical system, a color image of the sample surface in the same range as the ultra-depth image can be obtained. This color image has a small depth of focus unlike the super-depth image, but is useful when observing the outline of the sample surface or when positioning the sample to obtain a confocal image of a target portion. Further, by performing a synthesizing process in which the luminance signal of the color image is replaced with the luminance signal of the super-depth image, a color image having a deep focal depth (this is referred to as a color super-depth image) can be obtained.
[0005]
As described above, in an optical measuring device such as a color confocal microscope in which a monochromatic optical system and a white optical system share an objective lens and the optical axis thereof, separation between the monochromatic optical system and the white optical system, or the projection system Usually, a beam splitter or a half mirror is used for separation from the light receiving system.
[0006]
FIG. 4 is a diagram illustrating a configuration example of an optical system of a conventional color confocal microscope. In this configuration example, a confocal optical system (monochromatic optical system) 101 includes a monochromatic light source 102 for irradiating the sample wk with monochromatic light (for example, laser light), a collimating lens 103, a polarizing beam splitter 104, and a 波長 wavelength plate. 105, a horizontal / vertical deflection device 106 for scanning the sample wk with monochromatic light, a half mirror 107, an objective lens 108, a PH lens 109, a pinhole plate 110, and a light receiving element 111.
[0007]
The non-confocal optical system (white optical system) 112 includes a white light source 113 for irradiating the sample wk with white light (illumination light for capturing a color image), a collector lens 114, a condenser lens 115, a beam splitter 116, It includes a half mirror 107, an objective lens 108, an imaging lens 117, and a color image sensor 118. The objective lens 108 and its optical axis (and the half mirror 107) are common to the monochromatic optical system 101 and the white optical system 112.
[0008]
In the configuration of FIG. 4, a portion including the monochromatic light source 102 and the light receiving element 111 of the monochromatic optical system 101 is separated from the optical axis of the objective lens 108 by the half mirror 107. Further, a white light projection system including the white light source 113 and the lenses 114 and 115 of the white optical system 112 and a white light receiving system including the color imaging element 118 and the lens 117 are separated by the beam splitter 116.
[0009]
According to such an optical system, since both the monochromatic optical system 101 and the white optical system 112 always work, the image obtained from the light receiving element 111 of the monochromatic optical system 101 and the color image sensor 118 of the white optical system 112 are used. Can be superimposed and displayed in real time, or can be displayed simultaneously by dividing the screen.
[0010]
[Problems to be solved by the invention]
However, in the case of the optical system shown in FIG. 4, a part of the light emitted from the monochromatic light source 102 to the sample wk, reflected by the sample wk, and returned to the half mirror 107 passes through the half mirror 107 and reaches the color imaging element 118. I do. In the case of a sample wk having a high light reflectance such as a mirror surface, relatively strong monochromatic light reaches the color image sensor 118. Further, in order to increase the resolution of an image obtained from the light receiving element 111 of the monochromatic optical system 101, when a visible laser having a short wavelength is used as the monochromatic light source 102, the energy density of the laser spot formed on the color imaging element 118 is reduced. And the color image sensor (CCD) 118 may be damaged.
[0011]
When damage such as printing occurs on the color image sensor 118 (particularly, a color filter disposed immediately before the CCD), a problem such as color shift occurs in an image obtained from the color image sensor 118.
[0012]
As a first method for preventing such a phenomenon, as shown in FIG. 5, a configuration using a movable mirror 107 ′ instead of the half mirror 107 in FIG. 4 can be considered. In this configuration, when imaging is performed by the color imaging element 118 of the white optical system 112, the movable mirror 107 'is set to the position shown by the solid line to open the optical path between the objective lens 108 and the beam splitter 116. On the other hand, when acquiring an image by the light receiving element 111 of the monochromatic optical system 101, the movable mirror 107 'is switched to the position shown by the broken line, and the optical path between the objective lens 108 and the beam splitter 116 is blocked.
[0013]
In this way, the light emitted from the monochromatic light source 102 to the sample wk and reflected by the sample wk and returned is reflected by the movable mirror 107 ′, travels to the light receiving element 111, and reaches the color imaging element 118 of the white optical system 112. Never. Therefore, there is no possibility that the color imaging element 118 will be damaged by the laser spot having a high energy density.
[0014]
However, in the configuration of FIG. 5, only one of the monochromatic optical system 101 and the white optical system 112 is activated by switching the movable mirror 107 ′. Therefore, as shown in FIG. 4, the image obtained from the light receiving element 111 of the monochromatic optical system 101 and the image obtained from the color image sensor 118 of the white optical system 112 are superimposed and displayed in real time, or the screen is divided. Cannot be displayed at the same time.
[0015]
As another method for preventing the color image sensor 118 from being damaged by a laser spot having a high energy density, an optical filter is disposed in front of the color image sensor 118 or the imaging lens 117 in FIG. (Laser light) may be blocked. It is necessary to use an optical filter that attenuates the spectrum of the monochromatic light emitted from the monochromatic light source 102 and transmits other visible light components with as little attenuation as possible.
[0016]
In this case, there is no problem as in the configuration of FIG. An image obtained from the light receiving element 111 of the monochromatic optical system 101 and an image obtained from the color imaging element 118 of the white optical system 112 are displayed in real time in a superimposed manner, or the screen is divided and displayed simultaneously. In addition, it is possible to prevent the color image sensor 118 from being damaged by a laser spot having a high energy density. However, since an optical filter needs to be added before the color image sensor 118 or the imaging lens 117, it is disadvantageous in terms of space and low cost as compared with the configuration of FIG.
[0017]
The present invention has been made in view of the above-described problems, and it is possible that monochromatic light having a high energy density generated in a monochromatic optical system reaches a color image sensor of a white optical system without disadvantages in terms of space and cost. It is an object of the present invention to provide an optical measuring device capable of effectively preventing the occurrence of the optical measurement.
[0018]
[Means for Solving the Problems]
A first configuration of the optical measurement device according to the present invention includes a monochromatic optical system for irradiating a sample with monochromatic light from a monochromatic light source and receiving monochromatic light from the sample with a light receiving element, and white light from a white light source. An optical measurement device comprising a white optical system for irradiating a sample and receiving white light from the sample with a color image sensor, and an objective lens and an optical axis thereof common to the monochromatic optical system and the white optical system. The white optical system includes a white light projecting system including a white light source and a lens, a white light receiving system including a color image sensor and a lens, and a first half mirror for separating the white light projecting system from the optical axis of the objective lens. A second half mirror is provided between the first half mirror and the objective lens for separating a portion including the monochromatic light source and the light receiving element of the monochromatic optical system from the optical axis of the objective lens; Mirror passes monochromatic light A filter half mirror using a filter glass as a base material that allows most of the components of white light to pass therethrough, wherein the white light passing through the filter half mirror is configured to reach a color image sensor. I do.
[0019]
According to such a configuration, the component of the monochromatic light (laser light) emitted from the monochromatic light source (for example, laser) is removed when passing through the filter half mirror, and does not reach the color image sensor of the white light receiving system. Therefore, there is no possibility that the color imaging element is damaged by monochromatic light (laser light) having a high energy density. Further, a first half mirror for separating the white light projecting system from the optical axis of the objective lens, that is, a half mirror for separating the white light projecting system and the white light receiving system also has an optical filter function as a filter half mirror. Therefore, there is no need to separately provide an optical filter, which is advantageous in terms of space and cost.
[0020]
The second configuration of the optical measurement device according to the present invention includes a monochromatic optical system for irradiating a sample with monochromatic light from a monochromatic light source and receiving monochromatic light from the sample with a light receiving element, and white light from a white light source. An optical measurement device comprising a white optical system for irradiating a sample and receiving white light from the sample with a color image sensor, and an objective lens and an optical axis thereof common to the monochromatic optical system and the white optical system. The white optical system includes a white light projecting system including a white light source and a lens, a white light receiving system including a color image sensor and a lens, and a first half mirror or a first half mirror for separating the white light projecting system and the white light receiving system from each other. Including a beam splitter, a second half mirror for separating a portion including a monochromatic light source and a light receiving element of a monochromatic optical system from the optical axis of the objective lens is provided between the first half mirror or the beam splitter and the objective lens. The second half mirror is a filter half mirror that does not pass or reflects most of the monochromatic light, and is configured such that white light that has passed through the filter half mirror reaches the color image sensor. .
[0021]
According to such a configuration, most of the monochromatic light (laser light) emitted from the monochromatic light source (for example, laser) is removed when passing through the filter half mirror, and does not reach the white light receiving color imaging device. Therefore, there is no possibility that the color imaging element is damaged by monochromatic light (laser light) having a high energy density. A second half mirror for separating a portion including the monochromatic light source and the light receiving element of the monochromatic optical system from the optical axis of the objective lens, that is, a half mirror for separating the monochromatic optical system and the white optical system is a filter half mirror. Since the optical filter also has the function of an optical filter, there is no need to separately provide an optical filter, which is advantageous in terms of space and cost.
[0022]
In a preferred embodiment, the optical measuring device is a color confocal microscope equipped with a color imaging function. In other words, the monochromatic optical system is a confocal optical system that includes a pinhole plate provided in front of the light receiving element, and receives light when the sample surface is scanned with monochromatic light while changing the distance between the focus of the objective lens and the sample. It has a function of acquiring a height distribution and a super-depth image of the sample surface based on light receiving information obtained from the element, and a function of acquiring a color image of the sample surface with a color image sensor. In such a color confocal microscope, by using the filter half mirror as described above, the color image sensor can be used for a monochromatic light having a high energy density without increasing or minimizing the space required and the cost. This can eliminate the risk of damage.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0024]
FIG. 1 shows a schematic configuration of a system using a color confocal microscope that is an optical measurement device according to an embodiment of the present invention. This system (color confocal microscope system) 1 includes a color confocal microscope having a confocal optical system (corresponding to a monochromatic optical system) 2 and a non-confocal optical system (corresponding to a white optical system) 3 and a color confocal microscope. A controller including a laser drive circuit 44 of the focus microscope, a first AD converter 41, a CCD drive circuit 43, a second AD converter 42, an objective lens moving mechanism 40, a control unit 46 using a microcomputer, and the like are connected to the controller. A display device 47 and an input device (console) 48 are provided.
[0025]
First, the confocal optical system (monochromatic optical system) 2 of the color confocal microscope and its signal processing will be described. The confocal optical system 2 includes a light source 10 for irradiating the sample wk with monochromatic light (for example, laser light), a collimating lens 11, a polarizing beam splitter 12, a quarter-wave plate 13, a horizontal / vertical deflection device 14, and a half mirror 15. , An objective lens 17, a PH lens 18, a pinhole plate 9, a light receiving element 19, and the like.
[0026]
As the light source 10, for example, a semiconductor laser is used. However, the light source 10 is not limited to a laser, and may be a monochromatic light source. Further, even if the light source is not a monochromatic light source such as a mercury lamp, it can be used as a monochromatic light source by combining with a band filter. Laser light emitted from the light source 10 driven by the laser drive circuit 44 passes through the collimator lens 11, the optical path is bent by the polarization beam splitter 12, and passes through the １ ／ wavelength plate 13. Thereafter, the light is deflected in the horizontal (horizontal) direction and the vertical (vertical) direction by the horizontal / vertical deflection device 14, reflected by the half mirror 15 to bend the optical path, and placed on the sample stage 30 by the objective lens 17. The light is focused on the surface of the sample wk.
[0027]
The horizontal / vertical deflection device 14 includes a horizontal (resonant) scanner for horizontal deflection and a galvano (electromagnetic) scanner for vertical deflection. By deflecting the laser light in both the horizontal and vertical directions, the surface of the sample wk is scanned with the laser light. For convenience of description, the horizontal direction is referred to as an X direction, and the vertical direction is referred to as a Y direction. The objective lens 17 is driven in the Z direction (optical axis direction) by the objective lens moving mechanism 40. Thus, the distance between the focus of the objective lens 17 and the sample wk in the optical axis direction (that is, the height direction of the sample wk) can be changed.
[0028]
However, the distance in the optical axis direction between the focal point of the objective lens 17 and the sample wk can be changed by another method. For example, instead of driving the objective lens 17 in the Z direction, the sample stage 30 may be driven in the Z direction. Alternatively, a configuration in which the focal point of the objective lens 17 is moved in the Z direction by inserting a lens whose refractive index changes between the objective lens 17 and the sample wk is also possible.
[0029]
In the color confocal microscope of the present embodiment, the objective lens 17 can be electrically moved in the Z-axis direction via the objective lens moving mechanism 40 by a control signal from the control unit 46, and the sample stage 30 is manually operated by the stage. It can be displaced in the X direction, the Y direction, and the Z direction by manual operation via the mechanism 31. In addition, the objective lens 17 can be moved up and down via the control unit 46 and the objective lens moving mechanism 40 by a key operation of the input device 48 (for example, an operation of an up / down key).
[0030]
The laser beam reflected by the sample wk is reflected by the half mirror 15 through the objective lens 17 and reversely passes through the quarter-wave plate 13 via the horizontal / vertical deflection device 14 so as to follow the above optical path in reverse. . As a result, the laser light passes through the polarizing beam splitter 12 and is collected by the PH lens 18. The collected laser light passes through the pinhole of the pinhole plate 9 arranged at the focal position of the PH lens 18 and enters the light receiving element 19. The light receiving element 19 is composed of, for example, a photomultiplier tube (photomultiplier tube) or a photodiode, and converts the amount of received light into an electric signal. The electric signal corresponding to the amount of received light is provided to the first AD converter 41 via an output amplifier and a gain control circuit (not shown), and is converted into a digital value.
[0031]
The height (depth) information of the sample wk can be acquired by the confocal optical system 2 configured as described above. The principle will be briefly described below.
[0032]
As described above, when the objective lens 17 is driven in the Z direction (optical axis direction) by the objective lens moving mechanism 40, the relative distance in the optical axis direction between the focal point of the objective lens 17 and the sample wk changes. When the focus of the objective lens 17 is focused on the surface of the sample wk, the laser light reflected on the surface of the sample wk is condensed by the PH lens 18 through the above-described optical path, and almost all the laser light is focused. It passes through the pinhole of the hole plate 9. Therefore, at this time, the amount of light received by the light receiving element 19 is maximized. Conversely, when the focus of the objective lens 17 is shifted from the surface of the sample wk, the laser light condensed by the PH lens 18 focuses on a position shifted from the pinhole plate 9, so that a part of the laser light Only the pinhole can pass. As a result, the amount of light received by the light receiving element 19 is significantly reduced.
[0033]
Therefore, if the amount of light received by the light receiving element 19 is detected at any point on the surface of the sample wk while driving the objective lens 17 in the Z direction (optical axis direction), the objective lens 17 when the amount of received light is maximized is detected. (Distance in the optical axis direction between the focal point of the objective lens 17 and the sample wk) can be uniquely obtained as height information.
[0034]
In practice, each time the objective lens 17 is moved by one step (one pitch), the surface of the sample wk is scanned by the horizontal / vertical deflection device 14 to obtain the amount of light received by the light receiving element 19. When the objective lens 17 is moved in the Z direction from the lower end to the upper end of the measurement range in the Z direction, light reception amount data that changes according to the Z direction position is obtained for each point (pixel) in the scanning range.
[0035]
FIG. 2 is a graph illustrating an example of the amount of received light that changes according to the position of the objective lens 17 in the Z direction. Based on such received light amount data, the maximum received light amount and the Z-direction position at that time are obtained for each point (pixel). Therefore, the distribution of the surface height of the sample wk on the XY plane is obtained. This process is executed by the control unit 46 using a microcomputer.
[0036]
The obtained surface height distribution information can be displayed on the monitor screen of the display device 47 by several methods. For example, the height distribution (surface shape) of the sample can be displayed three-dimensionally by three-dimensional display. Alternatively, the height data can be converted into luminance data to be displayed as a two-dimensional distribution of brightness. By converting the height data into color difference data, the height distribution can be displayed as a color distribution.
[0037]
Further, a surface image (monochrome image) of the sample wk can be obtained from a luminance signal using the received light amount obtained for each point (pixel) in the XY scanning range as luminance data. If a luminance signal is generated using the maximum amount of received light in each pixel as luminance data, an ultra-deep image with an extremely deep focal depth focused at each point having a different surface height can be obtained. When the height (Z-direction position) at which the maximum amount of received light is obtained at an arbitrary pixel of interest is fixed, the amount of received light of a pixel having a large height difference from the pixel of interest is significantly small, and An image in which only portions having the same height are bright (ie, a slice image) is obtained.
[0038]
Next, the non-confocal optical system (white optical system) 3 and its signal processing will be described. The non-confocal optical system 3 includes a white light source 20, a collector lens 21, a condenser lens 22, a filter half mirror 16, a half mirror 15, an objective lens for irradiating the sample wk with white light (illumination light for capturing a color image). 17, an imaging lens 23 and a color CCD (color image sensor) 24 are included. The half mirror 15 and the objective lens 17 are shared by the confocal optical system 2 and the non-confocal optical system 3, and the optical axis of the objective lens 17 is common to the confocal optical system 2 and the non-confocal optical system 3.
[0039]
For example, a white lamp is used as the white light source 20, but natural light or indoor light may be used without providing a special light source. The white light emitted from the white light source 20 passes through the collector lens 21 and the condenser lens 22, is reflected by the filter half mirror 16, the optical path is bent, passes through the half mirror 15, and is sampled on the sample stage 30 by the objective lens 17. It is focused on the surface of wk.
[0040]
The white light reflected by the sample wk passes through the objective lens 17 and the half mirror 15 so as to follow the above optical path in reverse. Then, the light passing through the filter half mirror 16 passes through the imaging lens 23 and enters the color CCD 24 to form an image. The color CCD 24 is provided at a position conjugate with or close to the pinhole of the pinhole plate 9 of the confocal optical system 2. The color image picked up by the color CCD 24 is read out by the CCD drive circuit 43, and its analog output signal is given to the second AD converter 42 and converted into a digital value.
[0041]
The filter half mirror 16 includes a white light receiving system (located on the optical axis of the objective lens 17) including the color CCD 24 and the imaging lens 23 of the white optical system 3, a white light source 20, and a white light including the two lenses 21 and 22. It corresponds to a first half mirror for separating the light from the light projecting system. Further, the above-mentioned half mirror 15 corresponds to a second half mirror provided between the filter half mirror 16 and the objective lens 17, and a monochromatic optical system (confocal optical system) 2 from the optical axis of the objective lens 17. This is for separating a portion including the light source 10 and the light receiving element 19.
[0042]
The filter half mirror 16 is formed of a metal film or a dielectric film on a filter glass in which impurities are mixed so as not to pass monochromatic light from the light source (semiconductor laser) 10 but to pass most components of white light from the white light source 20. Is deposited to form the reflection surface 16a. Therefore, the light that passes through the filter half mirror 16 and is imaged on the color CCD 24 by the imaging lens 23 hardly contains monochromatic light from the semiconductor laser 10. As a result, the possibility that the color CCD 24 (particularly the color filter) is damaged by the laser spot having a high energy density is eliminated. Further, it is advantageous in terms of space and cost as compared with a configuration in which an optical filter is separately provided in front of the color CCD 24 or the imaging lens 23 to block laser light. Note that the above filter glass is commercially available under the name of a sharp cut filter.
[0043]
The color image obtained as described above is displayed on the monitor screen of the display device 47 as an enlarged color image for observing the sample wk. The color image is also useful for locating the surface of the sample to be measured such as an ultra-depth image using a confocal optical system. Further, the super-depth image obtained by the confocal optical system 2 and the normal color image obtained by the non-confocal optical system 3 are combined to obtain a deep color super-depth with a focal depth substantially in focus at all pixels. Images can also be generated and displayed. For example, it is possible to generate a color super-depth image by a synthesis process in which a luminance signal forming a color image obtained by the non-confocal optical system 3 is replaced with a luminance signal of an ultra-depth image obtained by the confocal optical system 2. it can. Similarly, a color slice image can be generated by a synthesis process in which a luminance signal forming a color image obtained by the non-confocal optical system 3 is replaced with a luminance signal of a slice image obtained by the confocal optical system 2. .
[0044]
The controller including the control unit 46 is also in charge of the processing regarding the color image as described above. An input device 48 such as a console (operation console) and a display device 47 such as a CRT (cathode ray tube) or an LCD (liquid crystal display device) are connected to the controller.
[0045]
The user can set various measurement parameters using the input device 48 according to the guidance displayed on the screen of the display device 47. For example, a moving range (measurement range) and a moving pitch of the objective lens 17 in the Z direction are set. Alternatively, by setting the light receiving sensitivity (PMT gain) of the light receiving element 19 and the amount of attenuation by the ND filter according to the light reflectance of the surface of the sample wk, etc., the super-depth image or the slice image displayed on the screen is appropriate. Adjust so that the brightness (brightness) is high. Further, the shutter speed, gain, and white balance for obtaining a color image by the color CCD 24 are set.
[0046]
FIG. 3 shows a schematic configuration of a color confocal microscope system according to another embodiment of the present invention. In the configuration shown in FIG. 1, a filter half mirror is used as a first half mirror for separating the white light projecting system including the white light source 20 and the two lenses 21 and 22 of the white optical system 3 from the optical axis of the objective lens 17. 3, the filter half mirror 16 is used as the second half mirror for separating the portion including the monochromatic light source 10 and the light receiving element 19 of the monochromatic optical system 2 from the optical axis of the objective lens 17. ing.
[0047]
Also in this configuration, since the light that passes through the filter half mirror 16 and is imaged on the color CCD 24 by the imaging lens 23 contains almost no monochromatic light from the semiconductor laser 10, the color spot is formed by a laser spot having a high energy density. The possibility that the CCD 24 is damaged is eliminated. Moreover, it is advantageous in terms of space and cost as compared with a configuration in which an optical filter is separately provided in front of the color CCD 24 or the imaging lens 23 to block laser light.
[0048]
Further, in the configuration shown in FIG. 3, a beam splitter may be used instead of the first half mirror 15, or as in the conventional configuration shown in FIG. The light projecting system may be arranged on the optical axis of the objective lens 17, and the optical axis of the white light receiving system including the color CCD 24 and the imaging lens 23 may be arranged at right angles to the optical axis of the objective lens 17.
[0049]
In the configuration shown in FIG. 3, the filter half mirror 16 only needs to reflect monochromatic light from the semiconductor laser 10, and can be designed to function as a perfect mirror for the monochromatic light. In this case, it is not always necessary to use a commercially available sharp cut filter as the base material used for the filter half mirror 16. That is, by designing the mirror (reflection film), it is possible to realize the filter half mirror 16 so that most of the monochromatic light is reflected without passing through. In addition, if the reflectance of the monochromatic light (laser light) by the filter half mirror 16 can be increased, the utilization efficiency of the monochromatic light (laser light) can be increased.
[0050]
Further, if the optical system as shown in FIG. 3 is applied to a fluorescence confocal microscope that irradiates the sample wk with laser light as excitation light and observes fluorescence excited from the sample wk, the adverse effect of the white optical system 3 is eliminated. The effect is also obtained. That is, when the irradiation light emitted from the white light source 20 irradiates the sample wk and passes through the filter half mirror 16, the wavelength component of the laser light is removed. When the target portion is searched), the fluorescent substance in the sample wk is not unnecessarily excited. As a result, the fluorescent substance in the sample wk is first excited and emits fluorescence when the laser light is irradiated on the sample wk after switching from the observation by the white optical system 3 to the measurement by the monochromatic optical system 2, and the appropriate fluorescence measurement is performed. It is possible to do.
[0051]
As described above, the embodiments of the present invention have been described including the modified examples as appropriate. However, the present invention is not limited to the above embodiments, and can be implemented in various forms. For example, the optical measuring device of the above embodiment is a reflection type color confocal microscope, but the present invention can be applied to a transmission type color confocal microscope. In the case of a transmission type color confocal microscope, laser light (monochromatic light) of a confocal optical system (monochromatic optical system) and white light of a non-confocal optical system (white optical system) are irradiated from the back surface of the sample. The monochromatic light source used in the confocal optical system is not limited to the laser light source, and the monochromatic light source may be configured by a combination of a light source including a plurality of wavelengths such as a mercury lamp and a band filter. The light source of the non-confocal optical system can be replaced by natural light or room light.
[0052]
【The invention's effect】
As described above, according to the optical measurement apparatus of the present invention, particularly the color confocal microscope, the monochromatic light having a high energy density generated by the monochromatic optical system without the disadvantage in space and low cost. Can be effectively prevented from reaching the color image sensor of the white optical system, and the possibility that the color image sensor is damaged by monochromatic light having high energy density can be eliminated.
FIG. 1 is a diagram showing a schematic configuration of a system using a color confocal microscope which is an optical measurement device according to an embodiment of the present invention.
FIG. 2 is a graph illustrating an example of a light receiving amount that changes according to a Z-direction position of an objective lens.
FIG. 3 is a diagram showing a schematic configuration of a color confocal microscope system according to another embodiment of the present invention.
FIG. 4 is a diagram showing a configuration example of an optical system of a conventional color confocal microscope.
FIG. 5 is a diagram showing another configuration example of the optical system of the conventional confocal microscope.
[Explanation of symbols]
2 Monochromatic optical system (confocal optical system)
3 White optical system (non-confocal optical system)
9 Pinhole plate 10 Monochromatic light source 15 Half mirror 16 Filter half mirror 17 Objective lens 19 Light receiving element 20 White light source 21, 22 White light projecting lens 23 White light receiving system lens 24 Color imaging device (color CCD)
wk sample

Claims (3)

A monochromatic optical system for irradiating the sample with monochromatic light from a monochromatic light source and receiving monochromatic light from the sample with a light-receiving element, and color imaging of white light from the sample by irradiating the sample with white light from a white light source An optical measurement device comprising a white optical system for receiving light by an element, and an objective lens and an optical axis thereof are common to the monochromatic optical system and the white optical system, wherein the white optical system includes a white light source and A white light projecting system including a lens, a white light receiving system including a color image sensor and a lens, and a first half mirror for separating the white light projecting system from an optical axis of the objective lens,
A second half mirror is provided between the first half mirror and the objective lens for separating a portion including a monochromatic light source and a light receiving element of the monochromatic optical system from an optical axis of the objective lens,
The first half mirror is a filter half mirror using, as a base material, a filter glass that passes most of the white light component without passing the monochromatic light, and the white light that has passed through the filter half mirror is the color image. An optical measurement device configured to reach an element. A monochromatic optical system for irradiating the sample with monochromatic light from a monochromatic light source and receiving monochromatic light from the sample with a light-receiving element, and color imaging of white light from the sample by irradiating the sample with white light from a white light source An optical measurement device comprising a white optical system for receiving light by an element, and an objective lens and an optical axis thereof are common to the monochromatic optical system and the white optical system, wherein the white optical system includes a white light source and A white light projecting system including a lens, a white light receiving system including a color imaging element and a lens, and a first half mirror or a beam splitter for separating the white light projecting system and the white light receiving system from each other,
A second half mirror is provided between the first half mirror or the beam splitter and the objective lens for separating a portion including a monochromatic light source and a light receiving element of the monochromatic optical system from an optical axis of the objective lens,
The second half mirror is a filter half mirror that does not pass or reflects most of the monochromatic light, and is configured such that white light that has passed through the filter half mirror reaches the color image sensor. Optical measuring device. The monochromatic optical system is a confocal optical system including a pinhole plate provided in front of a light receiving element, and the monochromatic optical system scans the sample surface with monochromatic light while changing the distance between the focus of the objective lens and the sample. Acquiring a height distribution and a super-depth image of the sample surface based on light receiving information obtained from a light receiving element, and having a function of acquiring a color image of the sample surface with the color imaging element. The optical measurement device according to claim 1.

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