JP6423261B2 - Microscope system, function calculation method, and program - Google Patents

Description

  The present invention relates to a microscope system, a method for calculating a function for calculating a set value of a correction apparatus for correcting spherical aberration, and a program.

  When observing a sample with a microscope, it is known that a different amount of spherical aberration occurs depending on the thickness of the cover glass, and the correction ring of the objective lens is known as a means for correcting the spherical aberration caused by the thickness of the cover glass. It has been.

  Conventionally, the correction ring has been used exclusively as a means for correcting spherical aberration caused by the thickness of the cover glass. However, in recent years when a method for observing the deep part of a sample (for example, a biological sample) has been developed and spread, It can also be used for the purpose of correcting spherical aberration that changes according to the depth of the target surface.

  However, it is not easy to determine whether or not the spherical aberration is corrected while observing the sample image. For this reason, the work of correcting the spherical aberration using the correction ring tends to be avoided, and at present, it cannot be said that the correction ring is sufficiently utilized as a means for correcting the spherical aberration.

  In relation to such a problem, for example, Patent Document 1 describes a technique for supporting the use of a correction ring by a microscope user. In Patent Document 1, the setting value of the correction ring for correcting the spherical aberration is calculated at a plurality of Z positions, and the Z position and the spherical aberration are corrected from a combination of the plurality of Z positions and the setting value of the correction ring. A technique for calculating a function indicating a relationship with a setting value of a correction ring by interpolation is described. By providing the microscope system with a function for supporting the use of the correction ring as described in Patent Document 1, the microscope user can be encouraged to use the correction ring.

JP 2014-160213 A

  However, Patent Document 1 has almost no specific description of the function calculation method. For this reason, depending on the function calculation method, the accuracy of the function obtained by the technique described in Patent Document 1 (that is, the accuracy with which the spherical aberration is corrected by the set value for each Z position determined from the function) can be improved. There can be room.

  In light of the circumstances as described above, an object of the present invention is to provide a technique that contributes to correcting spherical aberration easily and with high accuracy.

According to a first aspect of the present invention, there is provided an objective lens and a correction device that corrects spherical aberration, and sample image data in each of a plurality of states having different setting values of the correction device for each Z position of the objective lens. And a target value at the Z position, which is a set value of the correction device for correcting spherical aberration, based on a plurality of image data acquired for each Z position by the microscope device, and at least said three and Z position based on a combination of the target value of at least three Z positions, the function indicating the relationship between the Z position and the target value, and a calculation device for calculating by interpolation or function approximation, the calculation The apparatus includes a target value at each of the two Z positions and the two Z positions for every two adjacent Z positions of the plurality of Z positions from which the microscope apparatus has acquired image data. Based on two target values, the inclination of the target value with respect to the Z position is calculated, and based on the inclination of the target value with respect to a plurality of Z positions, which is composed of the inclination of the target value with respect to the Z position calculated for each of the two Z positions. The plurality of Z ranges are determined, and for each of the determined plurality of Z ranges, a partial function indicating a relationship between a Z position and a target value having the Z range as a domain is calculated by interpolation or function approximation. A microscope system is provided.

A second aspect of the present invention, in the microscope system according to the first state-like, further, in accordance with the Z position of the objective lens, is calculated on the basis of the function calculated in with the Z position the computing device There is provided a microscope system including a correction device control device that changes a set value of the correction device to a target value.

According to a third aspect of the present invention, there is provided the microscope system according to the first aspect or the second aspect , wherein the correction device is a correction ring that moves a lens in the objective lens.

According to a fourth aspect of the present invention, there is provided a method for calculating a function indicating a relationship between a Z position of an objective lens and a setting value of a correction device for correcting spherical aberration, the correction correcting the objective lens and spherical aberration. A microscope apparatus that acquires image data of a sample in each of a plurality of states with different setting values of the correction device for each Z position of the objective lens, and the arithmetic unit is a Z position in the microscope apparatus. Based on a plurality of pieces of image data acquired every time, a target value at the Z position, which is a setting value of the correction device for correcting spherical aberration, is calculated, and at least three Z positions and targets at the at least three Z positions are calculated. based on the combination of the values, a function indicating the relationship between the Z position and the target value is calculated by interpolation or function approximation, to calculate the function, the microscope acquires the image data For each two adjacent Z positions out of a plurality of Z positions, the inclination of the target value with respect to the Z position based on the two Z positions and the two target values consisting of the target values at each of the two Z positions. Determining the plurality of Z ranges based on slopes of target values for a plurality of Z positions, each comprising a slope of a target value for the Z positions calculated for each of the two Z positions; For each of the plurality of determined Z ranges, a method including calculating a partial function indicating a relationship between a Z position and a target value with the Z range as a domain by interpolation or function approximation is provided.

According to a fifth aspect of the present invention, there is provided a plurality of sample image data obtained by a microscope apparatus provided with an objective lens and a correction device for correcting spherical aberration for each Z position of the objective lens, each of which is the correction Processing for calculating a target value at the Z position, which is a setting value of the correction device for correcting spherical aberration, based on a plurality of image data acquired in a state where the setting values of the device are different; A process of calculating a function indicating a relationship between a Z position and a target value by interpolation or function approximation based on a combination of at least three Z positions from which data has been acquired and target values at the at least three Z positions. For each two adjacent Z positions of the plurality of Z positions from which the microscope apparatus has acquired image data, the two Z positions and the target values at the two Z positions are used. Based on the two target values, the inclination of the target value with respect to the Z position, and the inclination of the target value with respect to the Z position calculated for each of the two Z positions, Based on the slope, determining the plurality of Z ranges and, for each of the determined plurality of Z ranges, interpolating or representing a partial function indicating a relationship between a Z position having the Z range as a domain and a target value There is provided a program that causes a computer to execute processing including calculating by function approximation .

  According to the present invention, it is possible to provide a technique that contributes to correcting spherical aberration easily and with high accuracy.

It is the figure which illustrated the composition of the microscope system concerning Example 1 of the present invention. It is the figure which illustrated the structure of the arithmetic unit illustrated by FIG. It is the figure which illustrated the structure of the microscope apparatus illustrated by FIG. It is a flowchart of the function calculation process performed with the microscope system which concerns on Example 1 of this invention. It is a flowchart which shows the specific example which automated the process of step S6 shown in FIG. It is the figure which showed the inclination of the target value with respect to the Z position calculated by the process of step S11 shown in FIG. It is the figure illustrated about the several Z range determined by the process of step S12 shown in FIG. It is the figure which showed an example of all the functions calculated by the process of step S14 shown in FIG. It is the figure which showed another example of all the functions calculated by the process of step S14 shown in FIG. It is the figure which showed another example of all the functions calculated by the process of step S14 shown in FIG. It is a flowchart which shows another specific example which automated the process of step S6 shown in FIG. It is a flowchart which shows the specific example which semi-automated the process of step S6 shown in FIG. It is a figure for demonstrating the method to input the designation | designated of the Z range received by step S32 shown in FIG. It is a flowchart of the spherical aberration correction process performed with the microscope system which concerns on Example 1 of this invention. It is a flowchart of the target value calculation process performed for every Z position in the microscope system which concerns on Example 1 of this invention. It is a figure for demonstrating the target value calculation process shown in FIG. It is the figure which divided the whole field of image data into nine fields, and showed the example which computes a field target value for every field. It is a flowchart of another target value calculation process performed for every Z position with the microscope system which concerns on Example 1 of this invention. It is the figure which divided | segmented the whole area | region of image data into nine area | regions, and showed the example which calculates an area combination for every area | region. It is a flowchart of the further another target value calculation process performed for every Z position with the microscope system which concerns on Example 1 of this invention. It is a figure for demonstrating the target value calculation process shown in FIG. It is a flowchart of the further another target value calculation process performed for every Z position with the microscope system which concerns on Example 1 of this invention. It is a flowchart of the process of step S79 of the target value calculation process shown in FIG. It is a figure for demonstrating the process shown in FIG. 23, and is a figure which shows the method of calculating the function of a target value and an evaluation value. It is a figure for demonstrating the process shown in FIG. 23, and is a figure which shows the method of calculating the function of a target value and Z position. It is the figure which arranged the image of the sample obtained for every Z position and every set value of a correction ring. It is the figure which illustrated the structure of the microscope which concerns on Example 2 of this invention. It is the figure which illustrated the structure of the microscope which concerns on Example 3 of this invention. It is a flowchart of the process which calculates an evaluation value after processing image data.

  FIG. 1 is a diagram illustrating a configuration of a microscope system 1 according to the present embodiment. FIG. 2 is a diagram illustrating the configuration of the arithmetic device 20 illustrated in FIG. FIG. 3 is a diagram illustrating the configuration of the microscope 100 illustrated in FIG.

  A microscope system 1 shown in FIG. 1 includes a microscope 100, a microscope control device 10, a calculation device 20, a display device 30, and a plurality of input devices (keyboard 40, correction ring) for inputting instructions to the calculation device 20. An operation device 50 and a Z drive unit operation device 60) are provided.

  The microscope control device 10 is a device that controls the operation of the microscope 100 according to an instruction from the arithmetic device 20, and generates a control signal that controls the operation of various electric parts of the microscope 100. The microscope control device 10 includes a light source control device 11 that controls the output of the light source, a zoom control device 12 that controls the zoom magnification, a Z control device 13 that controls the Z position of the objective lens 110, and a setting value of the correction ring 111. And a correction ring control device 14 for controlling. Here, the Z position is a relative position in the optical axis direction of the objective lens 110 with respect to the sample S. The set value of the correction ring 111 is, for example, the rotation angle of the correction ring 111 with respect to the reference position.

  The arithmetic device 20 is a computer that performs various arithmetic processes. For example, as shown in FIG. 2, a CPU (Central Processing Unit) 21, a memory 22, an input I / F device 23, an output I / F device 24, and a storage A device 25 and a portable recording medium driving device 26 into which a portable recording medium 27 is inserted are provided, and these are connected to each other by a bus 28. The arithmetic unit 20 plays a role of instructing the microscope control device 10 to control the microscope 100, a role of generating image data based on an output from the microscope 100, and a setting value of the correction ring 111 for correcting the spherical aberration. Have a role to play. FIG. 2 is an example of the configuration of the arithmetic device 20, and the arithmetic device 20 is not limited to this configuration.

  The CPU 21 executes a predetermined program and performs arithmetic processing and the like. The memory 22 is, for example, a RAM (Random Access Memory), and temporarily stores a program or data stored in the storage device 25 or the portable recording medium 27 when the program is executed.

  The input I / F device 23 is a means for receiving signals from the keyboard 40, the correction ring operating device 50, the Z drive unit operating device 60, and the display device 30, and functions as an input receiving unit that receives input from the observer. . Further, the input I / F device 23 also receives a signal from an A / D converter 108 of the microscope 100 described later in FIG.

  The output I / F device 24 is means for outputting signals to the display device 30 and the microscope control device 10. That is, the output I / F device 24 functions as a display control unit that controls the display of the display device 30 and also functions as a microscope control instruction unit that instructs the microscope control device 10 to control the microscope 100.

  The storage device 25 is, for example, a hard disk storage device, and is mainly used for storing various data and programs. The portable recording medium driving device 26 accommodates a portable recording medium 27 such as an optical disk or a compact flash (registered trademark), and the portable recording medium 27 has a role of assisting the storage device 25.

  The display device 30 is, for example, a liquid crystal display device, an organic EL display device, a CRT display device, or the like. The display device 30 may include a touch panel sensor, and in that case, the display device 30 also functions as an input device.

  The correction ring operating device 50 is an input means for instructing the set value of the correction ring 111. When the user instructs the setting value of the correction ring 111 with the correction ring operating device 50, the correction ring control device 14 changes the setting value of the correction ring 111 to the instructed value.

  The Z drive unit operating device 60 is an input means for instructing a change in the Z position of the objective lens 110. When the user instructs the Z drive unit operating device 60 to change the Z position, the Z control device 13 moves the Z drive unit 109 in the optical axis direction to change the Z position of the objective lens 110.

  The microscope 100 is a two-photon excitation microscope. The sample S is a biological sample such as a mouse brain, for example, and a cover glass CG is placed on the sample S. As shown in FIG. 3, the microscope 100 includes a laser 101, a scanning unit 102, a pupil projection optical system 103, a mirror 104, a dichroic mirror 105, and an objective lens 110 on the illumination optical path.

  The laser 101 is, for example, an ultrashort pulse laser, and oscillates near-infrared laser light. The output of the laser 101 is controlled by the light source control device 11. That is, the light source control device 11 is a laser control device that controls the power of the laser light applied to the sample.

  The scanning unit 102 is scanning means for scanning the sample S two-dimensionally with laser light, and includes, for example, a galvano scanner or a resonance scanner. The zoom magnification changes as the scanning range of the scanning unit 102 changes. The scanning range of the scanning unit 102 is controlled by the zoom control device 12.

  The pupil projection optical system 103 is an optical system that projects the scanning unit 102 onto the pupil position of the objective lens 110. The dichroic mirror 105 is a light separating unit that separates the excitation light (laser light) and the detection light (fluorescence) from the sample S, and separates the laser light and the fluorescence according to the wavelength.

  The objective lens 110 is a dry or immersion objective lens including a correction ring 111 and is attached to the Z drive unit 109. The Z drive unit 109 is means for moving the objective lens 110 in the optical axis direction of the objective lens 110, and the movement of the Z drive unit 109 (that is, movement of the objective lens 110) is controlled by the Z control device 13.

  The correction ring 111 is a correction device that corrects spherical aberration by moving the lens in the objective lens 110 by changing the set value. The set value of the correction ring 111 is changed by the correction ring control device 14 (correction device control device). Note that the setting value of the correction ring 111 can be changed manually by directly operating the correction ring 111.

  The microscope 100 further includes a pupil projection optical system 106 and a photodetector 107 on the detection optical path (the reflection optical path of the dichroic mirror 105). The signal output from the photodetector 107 is output to the A / D converter 108.

  The pupil projection optical system 106 is an optical system that projects the pupil of the objective lens 110 onto the photodetector 107. The photodetector 107 is, for example, a photomultiplier tube (PMT), and outputs an analog signal corresponding to the amount of incident fluorescence. The A / D converter 108 converts the analog signal from the photodetector 107 into a digital signal (luminance signal) and outputs the digital signal to the arithmetic unit 20.

  In the microscope system 1 configured as described above, the microscope 100 scans the sample S with a laser beam using the scanning unit 102, and detects fluorescence from each position of the sample S with the photodetector 107. Then, the arithmetic unit 20 generates image data based on the digital signal (luminance signal) obtained by converting the signal from the photodetector 107 and the scanning information of the scanning unit 102. That is, in the microscope system 1, the microscope apparatus configured by the microscope 100 and the arithmetic device 20 acquires the image data of the sample S.

  FIG. 4 is a flowchart of a function calculation process performed in the microscope system 1. Hereinafter, a function calculation process that is a process for calculating a function indicating a relationship between the Z position and the setting value (target value) of the correction ring for correcting the spherical aberration will be described with reference to FIG.

  The microscope system 1 first determines a plurality of Z positions (step S1). Here, the computing device 20 determines a plurality of Z positions from which image data should be acquired in order to calculate the above function, based on information input by the user using the keyboard 40 or the like. For example, the user inputs the Z range and the Z interval from which image data is to be acquired, and the arithmetic unit 20 determines a plurality of Z positions from the Z range and the Z interval. The determined plurality of Z positions are stored in the storage device 25. The Z range is a range of the Z position.

  Next, the microscope system 1 changes the Z position to the initial position (step S2). Here, in accordance with an instruction from the arithmetic unit 20, the Z control unit 13 moves the Z driving unit 109 in the optical axis direction, and the Z position of the objective lens 110 is one of the plurality of Z positions determined in step S1. Change to some initial position. Thereby, the observation target surface of the sample S from which image data is acquired later is determined.

  When the Z position is changed, the microscope system 1 calculates a set value (hereinafter referred to as a target value) of the correction ring 111 for correcting the spherical aberration on the observation target surface (step S3). Here, based on a plurality of image data acquired by the microscope apparatus at the current Z position, the arithmetic unit 20 calculates a target value at the Z position. The processing for calculating the target value will be described in detail later with reference to FIGS.

  When the target value is calculated, the microscope system 1 determines whether the target value has been calculated at all of the plurality of Z positions determined in step S1 (step S4). When the target value is not calculated at all the Z positions, the microscope system 1 sets the Z position of the objective lens 110 to the Z position where the target value is not calculated among the plurality of Z positions determined in step S1. The target value is calculated at the new Z position (step S3). By repeating this, a plurality of target values at a plurality of Z positions are calculated based on a plurality of image data acquired for each Z position.

  When the target values are calculated at all the Z positions, the microscope system 1 calculates a function indicating the relationship between the Z positions and the target values (step S6), and ends the function calculation process. Here, the arithmetic unit 20 calculates the function by interpolation or function approximation based on a combination of at least three Z positions and target values at the at least three Z positions. The calculated function is stored in the storage device 25. For the interpolation, any interpolation method such as Lagrangian interpolation or spline interpolation may be employed. Arbitrary approximation methods such as the least square method can be adopted for the function approximation. The function calculated in step S6 may be automatically calculated by the calculation device 20 based on the already acquired information, or calculated by the user after further input of information by the user. That is, the arithmetic unit 20 may calculate semi-automatically. A specific example of the process in step S6 will be described later.

  The microscope system 1 can easily calculate a function indicating the relationship between the Z position and the target value by executing the processing shown in FIG. Since the function is calculated by interpolation or function approximation, the function can be calculated from a relatively small number of combinations of Z positions and target values. For this reason, it is possible to reduce the number of times image data is acquired, and as a result, it is possible to calculate the function in a short time while suppressing damage to the sample S. Furthermore, since the function is calculated based on a combination of at least three Z positions and target values at at least three Z positions, the sample S has a structure in which the refractive index differs greatly depending on the depth. Also, it is possible to calculate a function that captures the change in the target value accompanying the change in the refractive index. This point will be described in more detail below.

  FIG. 5 is a flowchart showing a specific example in which the process of step S6 shown in FIG. 4 is automated. FIG. 6 is a diagram showing the inclination of the target value with respect to the Z position calculated in the process of step S11 shown in FIG. FIG. 7 is a diagram illustrating a plurality of Z ranges determined in the process of step S12 shown in FIG. 8 to 10 are diagrams showing examples of all functions calculated in the process of step S14 shown in FIG.

  The microscope system 1 calculates the inclination of the target value with respect to the Z position for every two adjacent Z positions of the plurality of Z positions whose target values have been calculated in step S3 (step S11). Here, the arithmetic unit 20 calculates, based on two target values including two Z positions and target values at each of the two Z positions, for every two adjacent Z positions of the plurality of Z positions. The inclination of the target value with respect to the position is calculated. FIG. 6 is a diagram illustrating the inclination calculated in step S11. The horizontal axis represents the set value (that is, target value) of the correction ring 111 for correcting the spherical aberration. The vertical axis indicates the depth of the observation target surface, and corresponds to the Z position of the objective lens 110 on a one-to-one basis. The tilt depends on the refractive index of the sample between the two Z positions, and the larger the refractive index of the sample relative to the refractive index used as a reference in designing the objective lens 110 (hereinafter referred to as the reference refractive index). The absolute value becomes large. This is because larger spherical aberration occurs as the difference between the reference refractive index and the refractive index of the sample increases.

  Next, the microscope system 1 determines a plurality of Z ranges (step S12). Here, in step S11, the arithmetic unit 20 determines a plurality of Z ranges based on the inclinations of the target values with respect to a plurality of Z positions, which are composed of inclinations of the target values with respect to the Z positions calculated for every two Z positions. . More specifically, attention is paid to a change in inclination. For example, the Z range in which the change in inclination is equal to or greater than a certain threshold value may be specified, and the Z range may be determined so that the specified Z position is located at the boundary. In the region where the change in inclination is small (Z range), the refractive index of the sample is considered to be substantially constant. On the other hand, it is considered that the refractive index of the sample changes greatly in the region where the change in inclination is large (Z range). By determining the Z range with the Z position having a large change in inclination as a boundary, the Z range can be determined for each homogeneous region with little change in refractive index. In FIG. 7, the Z position corresponding to the depth of the observation target surface of 100 μm (hereinafter referred to as Z100) and the Z position corresponding to the depth of the observation target surface of 500 μm (hereinafter referred to as Z500) as the Z position having a large change in inclination. In this example, three Z ranges (first Z range, second Z range, and third Z range) are determined.

When a plurality of Z ranges are determined, the microscope system 1 calculates a partial function for each Z range (step S13). Here, the arithmetic unit 20 calculates, for each of a plurality of Z ranges determined in step S12, a partial function indicating the relationship between the Z position and the target value with the Z range as a domain by interpolation or function approximation. FIG. 8 shows an example in which a partial function having a second Z range as a domain is calculated by linearly interpolating a target value in Z100 and a target value in Z500. FIG. 9 shows an example in which a partial function having the second Z range as a domain is calculated by the least square method. FIG. 10 shows an example in which a partial function having the second Z range as a domain is calculated by function approximation of a quadratic function. 8 to 10 show examples in which partial functions are calculated by linear interpolation for the first Z range and the third Z range.
Finally, the microscope system 1 calculates all functions including a set of partial functions (step S14), and ends the process of FIG.

  The microscope system 1 can automatically calculate a function indicating the relationship between the Z position and the target value by executing the processing shown in FIGS. 4 and 5. Further, the Z range is determined for each region that is substantially uniform with little change in refractive index, and the entire function is calculated from the partial functions calculated for each Z range. For this reason, even when the sample S has a structure in which the refractive index is greatly different depending on the depth, a function for correcting the spherical aberration can be calculated with high accuracy. This is particularly suitable when a sample such as a brain having a structure in which layers having different refractive indexes are stacked is targeted. According to the microscope system 1, a function for correcting spherical aberration with high accuracy can be easily calculated.

  FIG. 11 is a flowchart showing another specific example in which the process of step S6 shown in FIG. 4 is automated. The microscope system 1 may execute the process shown in FIG. 11 instead of the process shown in FIG.

  First, the microscope system 1 calculates a partial function by linear interpolation for every two adjacent Z positions of the plurality of Z positions whose target values have been calculated in step S3 (step S21). Here, the arithmetic unit 20 calculates the two Z positions based on two adjacent Z positions of the plurality of Z positions and two target values composed of target values in each of the two Z positions. A partial function indicating the relationship between the Z position and the target value with the Z range defined at both ends as a domain is calculated by linear interpolation. This process is performed for every two adjacent Z positions.

  Thereafter, the microscope system 1 calculates all functions including a set of partial functions (step S22), and ends the process of FIG. FIG. 6 shows a function indicating the relationship between the Z position calculated by the processing of FIG. 11 and the target value.

  The process of FIG. 11 corresponds to the case where the area between two adjacent Z positions is determined as the Z range in the process of FIG. Therefore, the microscope system 1 can obtain the same effect as the case where the processing shown in FIGS. 4 and 5 is executed by executing the processing shown in FIGS.

  FIG. 12 is a flowchart showing a specific example in which the process of step S6 shown in FIG. 4 is semi-automated. FIG. 13 is a diagram for explaining a method for inputting the designation of the Z range received in step S32 shown in FIG. The microscope system 1 may execute the process shown in FIG. 12 instead of the process shown in FIG.

  First, the microscope system 1 causes the display device 30 to display the plurality of Z positions and the plurality of target values whose target values are calculated in Step S3 (Step S31). Here, the computing device 20 (output I / F device 24) causes the display device 30 to display a plurality of Z positions and a plurality of target values made up of target values at each of the plurality of Z positions. FIG. 13 shows an example in which a plurality of Z positions and a plurality of target values are displayed by plotting points indicating combinations of Z positions and target values. Note that the display method is not limited to the example of FIG. 13, and each numerical value may be displayed in a table format, for example.

  Next, the microscope system 1 accepts designation of a plurality of Z ranges (step S32). Here, for example, a user who has confirmed the information displayed on the display device 30 in step S31 designates a plurality of Z ranges using the keyboard 40 or the like. FIG. 13 illustrates a state in which a Z range is designated on a screen on which a plurality of Z positions and a plurality of target values are displayed. When a plurality of Z ranges are specified, the arithmetic unit 20 receives information regarding the specified Z ranges.

Thereafter, the microscope system 1 calculates a partial function for each Z range (step S33). Here, for each Z range designated in step S32 after the display device 30 displays a plurality of Z positions and a plurality of target values, the computing device 20 uses the Z position and the target value with the Z range as a domain. Is calculated by interpolation or function approximation.
Finally, the microscope system 1 calculates all the functions including the set of partial functions calculated in step S33 (step S34), and ends the process of FIG.

  The microscope system 1 executes the processes shown in FIGS. 4 and 12, so that even if it is difficult for the arithmetic device 20 to make a mechanical judgment, the user can see the information displayed on the display device 30. An almost homogeneous region with little change in refractive index can be designated as the Z range. Therefore, according to the microscope system 1, it is possible to easily calculate a function for correcting spherical aberration with high accuracy.

  FIG. 14 is a flowchart of spherical aberration correction processing performed in the microscope system 1 according to the present embodiment. Hereinafter, with reference to FIG. 14, processing for correcting spherical aberration performed using the correction ring 111 in the microscope system 1 will be described. Note that the spherical aberration correction processing shown in FIG. 14 is performed immediately before the start of observation, for example.

  First, the microscope system 1 accepts designation of the Z position (step S41). Here, for example, the user designates the Z position by operating the Z drive unit operation device 60 in order to determine the observation target surface. Thereby, the arithmetic unit 20 receives the information regarding the Z position designated from the Z drive unit operating device 60. Further, the Z control device 13 controls the Z drive unit 109 to change the Z position of the objective lens 110 to the designated Z position. As a result, the observation target surface of the sample S is determined.

  Next, the microscope system 1 calculates a target value based on the Z position designated in step S41 and the function calculated in the function calculation process shown in FIG. 4 (step S42). Here, the arithmetic unit 20 calculates the target value at the current Z position based on the Z position (current Z position) designated in step S41 and the function calculated by the function calculation process shown in FIG.

  When the target value is calculated, the microscope system 1 sets the set value of the correction ring 111 as the target value (step S43). Here, the correction ring control device 14 changes the set value of the correction ring 111 to the target value calculated in step S42. The correction ring control device 14 may change the set value of the correction ring 111 to the target value calculated in step S42 automatically, that is, in accordance with an instruction from the arithmetic device 20. In addition, the target value calculated in step S42 is displayed on the display device 30 manually, and the correction ring control device 14 is operated by the user operating the correction ring operation device 50 based on the displayed target value. However, the set value of the correction ring 111 may be changed to the target value. The user may directly operate the correction ring 111 to change the set value of the correction ring 111 to the target value.

  Finally, the microscope system 1 sets the output of the laser 101 (step S44). Here, the light source control device 11 controls the power of the laser light applied to the sample S based on the image data acquired by the microscope device when the set value of the correction ring 111 is the target value. For example, the image data is acquired after changing the set value of the correction ring 111 in step S43, and the output of the laser 101 is set based on the brightness of the image calculated from the image data.

  The microscope system 1 can easily correct the spherical aberration that changes according to the depth of the observation target surface by executing the spherical aberration correction processing shown in FIG. Thereby, the optical performance of the microscope 100 can be fully exhibited, and a high-quality image can be obtained. Further, the microscope system 1 can calculate the target value at the current Z position by simple calculation based on the Z position and the function. For this reason, even when the sample S is observed while frequently changing the observation depth, the set value of the correction ring 111 can be changed to the target value corresponding to the depth in a short time. Since the adjustment work of the correction ring 111 can be automated, other automated processes, for example, a process of acquiring image data at a plurality of Z positions and automatically generating a three-dimensional image or an extended focus image, etc. Can be easily incorporated. Furthermore, in a state where the spherical aberration is corrected, a bright image is generally obtained as compared with a state where the spherical aberration is not corrected. For this reason, by setting the output of the laser 101 based on the image data acquired in a state where the spherical aberration is corrected, the output of the laser 101 can be suppressed and damage to the biological sample can be suppressed.

  Hereinafter, the target value calculation process performed in step S3 of the function calculation process shown in FIG. 4 will be specifically described. FIG. 15 is a flowchart of target value calculation processing performed for each Z position in the microscope system 1. FIG. 16 is a diagram for explaining the target value calculation processing shown in FIG.

  First, the microscope system 1 determines a plurality of set values of the correction ring 111 (step S51). Here, the arithmetic unit 20 determines a plurality of setting values of the correction ring 111 when the sample image data is acquired by the microscope apparatus. For example, as shown in FIG. 16A, the arithmetic unit 20 determines a range (operable range) in which the correction ring 111 can rotate itself or a range slightly narrower as the search range, and equalizes the search range. A predetermined number (here, 10) of set values (correction ring positions) to be divided are determined as a plurality of set values. FIG. 16A shows an example in which ten set values (correction ring positions) from θ1 to θ10 are determined.

  Next, the microscope system 1 changes the setting value of the correction ring 111 to the setting value determined in step S51 (step S52). Here, the correction ring control device 14 sets one of a plurality of set values determined in step S51 in accordance with an instruction from the arithmetic device 20. For example, the correction ring control device 14 changes the set value of the correction ring 111 to θ1 determined in step S51.

  When the set value of the correction ring 111 is changed, the microscope system 1 acquires the image data of the sample S (step S53). Here, the microscope apparatus acquires image data in accordance with an instruction from the arithmetic unit 20. For example, the microscope apparatus acquires image data in a state where the setting value of the correction ring 111 is θ1.

  Thereafter, the microscope system 1 determines whether or not the image data has been acquired with all the setting values determined in step S51 (step S54). If the image data has not been acquired with all the setting values, step S51 is performed. The process from S52 to step S54 is repeated. Thereby, the microscope apparatus acquires image data of the observation target surface of the sample S in each of a plurality of states with different setting values of the correction ring 111, and as a result, acquires a plurality of image data.

  When the image data is acquired with all the set values, the microscope system 1 calculates each evaluation value of the plurality of image data acquired in step S53 (step S55). Here, the arithmetic unit 20 calculates an evaluation value of the image data that indicates a larger value as the spherical aberration is corrected based on each of the plurality of image data, and as a result, a plurality of the plurality of image data An evaluation value is calculated. In general, since image data with corrected spherical aberration has a higher contrast, for example, a contrast value calculated using a contrast evaluation method for image data is used as the evaluation value. FIG. 16A shows the evaluation values of a plurality of image data acquired in step S53. In FIG. 16A, the image data is specified by the correction ring position (set value of the correction ring 111), and the evaluation value of the image data is shown as the contrast value.

The contrast value according to the contrast evaluation method is calculated based on the difference in luminance value between pixels constituting the image data. Specifically, for example, according to the following formula, a value obtained by integrating the square of the difference between the luminance values of two pixels located at positions shifted by n pixels in the x direction over the entire image data is calculated as the contrast value.

  Here, x is a variable that identifies a column of pixels that constitutes image data, and y is a variable that identifies a row of pixels that constitute image data. W is the number of pixels constituting the image data in the x direction (ie, the number of columns), and H is the number of pixels constituting the image data in the y direction (ie, the number of rows). f is a luminance value of the pixel, and n is an integer (for example, 5).

  When the evaluation value is calculated, the microscope system 1 determines whether or not a predetermined condition is satisfied (step S56). The predetermined condition may be, for example, whether or not the number of repetitions of the processing from step S52 to step S56 has reached a predetermined number, and whether or not the average interval of a plurality of set values is equal to or less than a predetermined value. It may be.

  If the predetermined condition is not satisfied in step S56, the microscope system 1 determines a plurality of setting values again (step S57), and then repeats the processing from step S52 to step S56.

  In step S57, the arithmetic unit 20 determines a plurality of set values so as to satisfy the following two conditions. The first condition is that the distribution range (that is, the search range) and the average interval of the plurality of setting values determined in step S57 are narrower than the distribution range and the average interval of the plurality of setting values. . The second condition is that the setting value of the correction ring 111 corresponding to the maximum evaluation value in step S55 is included in the distribution range of the plurality of setting values determined in step S57. In this specification, the setting value corresponding to the evaluation value refers to the setting value of the correction device when the image data for the evaluation value calculated from certain image data is acquired. Further, the evaluation value corresponding to the set value means an evaluation value calculated from the image data with respect to the set value of the correction apparatus when certain image data is acquired.

  As a result, the microscope apparatus repeats the process of acquiring a plurality of image data in a plurality of states with different setting values for each of the distribution ranges and average intervals of the plurality of setting values of the correction ring 111 set in the plurality of states. And the set value of the correction ring 111 corresponding to the maximum evaluation value calculated by the arithmetic unit 20 is included in the distribution range. Then, the arithmetic device calculates a plurality of evaluation values of the plurality of image data for each repetition.

  FIG. 16B shows evaluation values of a plurality of image data acquired based on the plurality of setting values determined in step S57. When comparing FIG. 16A and FIG. 16B, it can be confirmed that the plurality of set values (correction ring positions) shown in FIG. 16B satisfy the above two conditions. 16 (a) and 16 (b) show an example in which ten setting values (correction ring positions) are determined, but the number of setting values is set for each repetition. As long as the average interval of values becomes narrow, it is not limited to the same, and may be increased or decreased.

When the predetermined condition is satisfied in step S56, the microscope system 1 sets the target value based on the plurality of evaluation values calculated in step S55 and the plurality of setting values corresponding to the plurality of evaluation values. Calculation is performed (step S58), and the target value calculation process is terminated. Here, for example, the arithmetic unit 20 may calculate the set value of the correction ring 111 corresponding to the maximum evaluation value among the plurality of evaluation values calculated in step S55 in the last iteration as the target value. Further, the set value of the correction ring 111 corresponding to the maximum evaluation value among the plurality of evaluation values calculated in step S55 is not limited to the last repetition, and may be calculated as a target value. The arithmetic unit 20 stores the combination of the calculated target value and the current Z position in the storage device 25.
The microscope system 1 can calculate the target value with high accuracy with a relatively small number of acquisitions of image data by executing the target value calculation process shown in FIG.

  In addition, although the example which calculates evaluation value for every image data was shown in step S55 of FIG. 15, the whole area | region of image data is divided | segmented into several area | region, and evaluation value (henceforth, hereafter) is divided | segmented. In order to distinguish it from the evaluation value calculated for each image data, it may be referred to as a region evaluation value). In this case, in step S58, a target value for each region (to be distinguished from a target value calculated for the entire region, hereinafter referred to as a region target value) is calculated, and based on a plurality of region target values, A target value for the entire area is calculated.

  FIG. 17 shows an example in which the entire area W of the image data is divided into nine areas R1 to R9, and the area target value is calculated for each area. The target value for the entire region may be determined as an intermediate value (θ5), for example, in which the region target values are arranged in ascending or descending order (θ3: θ3: θ4: θ4: θ5: θ5: θ5: θ6: θ6) It may be determined to the mode value (θ5). The number of divisions is not limited to nine, and may be smaller or larger than nine.

  By calculating the area target value for each area and calculating the target value by statistical processing for a plurality of area target values, the image data has extremely high or low luminance compared to other pixel data Even when data is included, it is possible to evaluate the contrast of image data while suppressing the influence. For this reason, the set value for correcting the spherical aberration can be calculated correctly.

  FIG. 18 is a flowchart of another target value calculation process performed for each Z position in the microscope system 1. Some objective lenses 110 change the focal length of the objective lens 110 slightly by changing the setting value of the correction ring 111. The target value calculation process shown in FIG. 18 is performed when such an objective lens 110 is used. The target value calculation process shown in FIG. 18 differs from the target value calculation process shown in FIG. 15 in that the process from step S59 to step S61 is further performed following step S58. The other points are the same as the target value calculation process shown in FIG.

  When the target value is calculated in step S58, the microscope system 1 changes the Z position (step S59). Here, the Z control device 13 moves the Z drive unit 109 in the optical axis direction to change the Z position of the objective lens 110 in accordance with an instruction from the arithmetic unit 20. The amount of movement of the Z position is based on the maximum amount of movement of the observation target surface (that is, the maximum amount of change in the focal length of the objective lens 110) caused by the change when the set value of the correction ring 111 is changed within the operable range. Is also a small distance. This is sufficiently smaller than the change of the Z position in step S5 in FIG. As an example, in step S5, for example, the Z position is changed by 100 μm, whereas in step S59, the Z position is changed by 1 μm, for example.

  Next, the microscope system 1 determines whether or not the changed Z position is within a predetermined Z range (step S60). Here, for example, the changed Z position is not separated from the reference Z position determined in step S2 or S5 of FIG. 4 by the change in the setting value of the correction ring 111, which is caused by the change in the setting value of the correction ring 111. In this case, the arithmetic unit 20 determines that the Z position is within a predetermined Z range. The reference Z position is, for example, the Z position of the observation target surface determined in step S2 or step S5 in FIG. That is, the predetermined Z range is, for example, a Z range having a width twice as large as the maximum change amount of the focal length of the objective lens 110 around the Z position of the observation target surface determined in step S2 or step S5. is there.

  When the changed Z position is within the predetermined Z range, the microscope system 1 performs the processing from step S52 to step S58 at the changed Z position. Thereby, the arithmetic unit 20 calculates a target value for each Z position, and as a result, calculates a plurality of target values at a plurality of Z positions.

  When the changed Z position is outside the predetermined Z range, the microscope system 1 determines the evaluation value based on the plurality of target values at the plurality of Z positions and the evaluation values corresponding to the plurality of target values. A combination of the set value of the correction ring 111 estimated to be the maximum and the Z position is calculated (step S61), and the target value calculation process is terminated. Here, for example, the computing device 20 specifies the maximum evaluation value among the plurality of evaluation values corresponding to the plurality of target values, and sets the target value corresponding to the maximum evaluation value to the maximum evaluation value. Calculated as an estimated set value. Then, the arithmetic unit 20 causes the storage device 25 to store the combination of the set value estimated to have the maximum evaluation value and the Z position.

  The microscope system 1 executes the target value calculation process shown in FIG. 18, so that even when the focal length of the objective lens 110 changes depending on the set value of the correction ring 111, the number of image data acquisition times is relatively small. The combination of the set value of the correction ring 111 that corrects spherical aberration favorably and the Z position of the objective lens 110 can be calculated with high accuracy.

  In step S55 in FIG. 18, the entire area of the image data may be divided into a plurality of areas, and an area evaluation value may be calculated for each area. In this case, a plurality of area target values are calculated in step S58. To do. In step S61, based on the plurality of region target values at the plurality of Z positions and the region evaluation values corresponding to the plurality of region target values, the set value of the correction ring 111 that is estimated to have the maximum evaluation value, A combination of Z positions (to be distinguished from a combination calculated for the entire region, hereinafter referred to as a region combination) is calculated for each region. Thereafter, a combination for the entire region is calculated based on a plurality of region combinations.

  FIG. 19 shows an example in which the entire region W of the image data is divided into nine regions R1 to R9, and region combinations are calculated for each region. For example, the setting values constituting the area combination are the area target values calculated in step S58 arranged in ascending or descending order (θ3.6: θ3.7: θ4.4: θ4.4: θ4.5: θ4. 6: θ4.7: θ5.1: θ6.1) The intermediate value (θ4.5) may be determined, or the mode value (θ4.4) may be determined. In addition, the Z position that constitutes the region combination may be determined based on the determined set value, for example, and if it is an intermediate value (θ4.5), the value of the Z position corresponding to the intermediate value (Z2. 5) If it is the mode value (θ4.4), the Z position value (Z2.3) corresponding to the mode value may be determined. The number of divisions is not limited to nine, and may be smaller or larger than nine.

  A region combination is calculated for each region, and a combination of the set value of the correction ring 111 and the Z position, which is estimated to have the maximum evaluation value, is calculated by statistical processing for a plurality of region combinations. Accordingly, even when the image data includes pixel data having extremely high luminance or low luminance as compared with other pixel data, the influence of the image data can be suppressed and the contrast of the image data can be evaluated. For this reason, the set value for correcting the spherical aberration can be calculated correctly.

  FIG. 20 is a flowchart of still another target value calculation process performed for each Z position in the microscope system 1. FIG. 21 is a diagram for explaining the target value calculation processing shown in FIG. The target value calculation process shown in FIG. 20 will be described with reference to FIGS. Note that the processing from step S71 to step S75 shown in FIG. 20 is the same as the processing from step S51 to step S55 shown in FIG.

  When the evaluation value is calculated in step S75, the microscope system 1 calculates a target value based on the first coordinate information of the plurality of image data (step S76), and ends the target value calculation process. Note that the first coordinate information of image data refers to a combination of an evaluation value calculated from the image data and a setting value of the correction ring 111 corresponding to the evaluation value.

  In step S76, the arithmetic unit 20 first selects three or more image data from the plurality of image data acquired in step S73. The three or more pieces of image data are selected so as to include the image data for which the maximum value among the plurality of evaluation values calculated in step S75 is calculated.

  Thereafter, the arithmetic unit 20 calculates a target value, which is a setting value of the correction ring 111 for correcting the spherical aberration on the observation target surface, based on the first coordinate information of the three or more selected image data. Specifically, a function is calculated by interpolation or function approximation based on the first coordinate information of three or more image data. This function is a function related to the evaluation value and the set value. Then, a set value obtained from the peak coordinates of the calculated function (coordinates with the maximum evaluation value) is calculated as a target value. The arithmetic device 20 stores the combination of the calculated target value and the current Z position in the storage device 25.

In FIG. 21, three pieces of image data including image data for which the maximum evaluation value is calculated and image data before and after that (that is, set values are close) are selected, and three first items obtained from the image data are displayed. An example is shown in which a quadratic function is calculated by Lagrange interpolation from the coordinate information and the target value is calculated from the peak coordinates. For the interpolation, any interpolation method such as Lagrangian interpolation or spline interpolation may be employed. In addition, an arbitrary approximation method such as a least square method can be adopted for the function approximation.
The microscope system 1 can calculate the target value with high accuracy with a relatively small number of acquisition times of image data by executing the target value calculation process shown in FIG.

  The target value may be calculated by combining the target value calculation process shown in FIG. 15 and the target value calculation process shown in FIG. For example, the processing of step S56 and step S57 of FIG. 15 is added to the target value calculation processing shown in FIG. 20, and the distribution range of a plurality of setting values (so that the target value calculated in step S76 is included in the distribution range ( That is, the calculation of the target value may be repeated while gradually narrowing the search range) and the average interval. Thereby, the target value can be calculated with higher accuracy.

  FIG. 22 is a flowchart of still another target value calculation process performed for each Z position in the microscope system 1. FIG. 23 is a flowchart of the process in step S79 of the target value calculation process shown in FIG. 24 and 25 are diagrams for explaining the processing shown in FIG. 23. FIG. 24 shows a method for calculating a function of the target value and the evaluation value, and FIG. 25 calculates a function of the target value and the Z position. Shows how. The target value calculation process shown in FIG. 22 is performed when the objective lens 110 whose focal length is changed by changing the setting value of the correction ring 111 is used. The target value calculation process shown in FIG. 22 is different from the target value calculation process shown in FIG. 20 in that the process of step S76a is performed instead of step S76, and further, the processes of steps S77 to S79 are performed. ing. The other points are the same as the target value calculation process shown in FIG. Note that step S76a differs from step S76 in that an evaluation value corresponding to the target value is calculated in addition to the target value from the peak coordinates of the function.

  When the target value and the evaluation value are calculated in step S76a, the microscope system 1 changes the Z position (step S77). Further, it is determined whether or not the changed Z position is within a predetermined Z range (step S78). Note that the processing in step S77 and step S78 is the same as the processing in step S59 and step S60 shown in FIG.

  When the changed Z position is within the predetermined Z range, the microscope system 1 performs the processing from step S72 to step S76a at the changed Z position. Thereby, a target value and an evaluation value corresponding to the target value are calculated for each Z position, and as a result, a plurality of target values and a plurality of evaluation values at a plurality of Z positions are calculated. That is, a plurality of second coordinate information is calculated. Note that the second coordinate information means a combination of the Z position, the target value at the Z position, and the evaluation value corresponding to the target value at the Z position.

  When the changed Z position is outside the predetermined Z range, the microscope system 1 determines a combination of the set value and the Z position that are estimated to have the maximum evaluation value based on the plurality of second coordinate information. Calculation is performed (step S79), and the target value calculation process is terminated. Here, as shown in FIG. 23, the arithmetic unit 20 first selects three or more pieces of second coordinate information from the plurality of second coordinate information (step S79a). The three or more pieces of the second coordinate information are selected so as to include the second coordinate information having the maximum evaluation value among the plurality of second coordinate information. Thereafter, the computing device 20 calculates a function of the target value and the evaluation value (broken line in FIG. 24) by interpolation or function approximation based on the selected three or more second coordinate information (step S79b). At this time, information on the Z position included in the second coordinate information is not used for calculating the function. Next, the target value at the peak coordinate is calculated from the peak coordinate (the coordinate at which the evaluation value is maximized) of the function calculated at step S79b (step S79c). Furthermore, a function of the target value and the Z position (broken line in FIG. 25) is calculated by interpolation (for example, linear interpolation) based on the selected three or more second coordinate information (step S79d). At this time, the evaluation value information included in the second coordinate information is not used for the calculation of the function. Then, the Z position is calculated based on the target value calculated in step S79c and the function calculated in step S79d (step S79e). Finally, the combination of the target value calculated in step S79c and the Z position calculated in step S79e is calculated as a combination of the set value and Z position estimated to have the maximum evaluation value, and is stored in the storage device 25 (step S79f). The combination may be calculated in the same way in step S61 in FIG.

  The microscope system 1 executes the target value calculation process shown in FIG. 22, so that even when the focal length of the objective lens 110 changes depending on the setting value of the correction ring 111, the microscope system 1 can acquire a relatively small number of image data. The combination of the set value of the correction ring 111 that corrects spherical aberration favorably and the Z position of the objective lens 110 can be calculated with high accuracy.

  Although FIG. 22 shows an example in which the processing from step S72 to step S76a is performed for each Z position within the predetermined Z range, step S71 may be performed for each Z position. That is, for each Z position, a plurality of setting values (range of setting values of the correction ring for acquiring image data) of the correction ring 111 may be determined again.

  FIG. 26 is a diagram in which images of the specimen S obtained for each Z position and for each set value (angle) of the correction ring 111 are arranged. FIG. 26 shows a tendency that as the Z position becomes deeper, the set value of the correction ring 111 that can obtain a high contrast image becomes larger. Therefore, when such a tendency with respect to the Z position is known, a search range is determined based on this tendency for each Z position, and a plurality of set values are determined within the search range in step S71. Also good. In the example shown in FIG. 26, three setting values from θ1 to θ3 are determined for Z2, five setting values from θ1 to θ5 are determined for Z3, and five setting values for θ2 to θ6 are determined for Z4. To decide. Thereby, compared with the case where a plurality of setting values are not re-determined for each Z position, the search range can be narrowed, and the number of setting values determined in step S71 can also be reduced. For this reason, it is possible to calculate with high accuracy the combination of the setting value of the correction ring 111 and the Z position of the objective lens 110, which correct spherical aberration satisfactorily, with fewer image data acquisition times.

  Note that the width of the search range (the distance in the θ direction between L1 and L2) may be set for each objective lens based on, for example, the design value of the objective lens, Data as shown in FIG. 26 may be acquired in advance and set based on this data. In addition, the above-described tendency (that is, the tendency indicating the relationship between the Z position, the evaluation value, and the set value, for example, the slopes of L1 and L2) is the Z position calculated until the first several Z position changes. And may be calculated from information on a combination of target values.

  18 and 22 illustrate an example in which the Z position is changed to the next position after acquiring image data with all the setting values of the correction ring 111 determined without changing the Z position. As a result, image data acquired in each of a plurality of states having different setting values may be obtained for each Z position within a predetermined range. For this reason, the setting value of the correction ring 111 may be changed to the next setting value after image data is acquired at each Z position within a predetermined range without changing the setting value of the correction ring 111.

  FIG. 27 is a diagram illustrating the configuration of the microscope 200 according to the present embodiment. The microscope system according to this embodiment is different from the microscope system 1 shown in FIG. 1 in that a microscope 200 is included instead of the microscope 100. Since the other points are the same as those of the microscope system 1, the same components are referred to by the same reference numerals.

  The microscope 200 is a confocal microscope. The sample S is a biological sample such as a mouse brain, for example. As shown in FIG. 27, the microscope 200 includes a laser 201, a beam expander 202, a dichroic mirror 203, a scanning unit 204, a pupil projection optical system 205, and an objective lens 110 on the illumination optical path. Yes. Note that the objective lens 110, the Z driving unit 109 that moves the objective lens 110 in the optical axis direction, and the correction ring 111 that is a correction device that corrects spherical aberration by moving the lens in the objective lens 110 are described in the first embodiment. This is the same as the microscope 100.

  For example, the laser 201 oscillates laser light in the visible region, the ultraviolet region, and the infrared region. The output of the laser oscillated from the laser 201 is controlled by the light source control device 11. The beam expander 202 is an optical system that adjusts the luminous flux of laser light (collimated light) from the laser 201 in accordance with the pupil diameter of the objective lens 111. The dichroic mirror 203 is a light separating unit that separates the excitation light (laser light) and the detection light (fluorescence) from the sample S, and separates the laser light and the fluorescence according to the wavelength.

  The scanning unit 204 is scanning means for scanning the sample S two-dimensionally with laser light, and includes, for example, a galvano scanner or a resonance scanner. The zoom magnification changes as the scanning range of the scanning unit 204 changes. The scanning range of the scanning unit 204 is controlled by the zoom control device 12. The pupil projection optical system 205 is an optical system that projects the scanning unit 204 onto the pupil position of the objective lens 110.

  The microscope 200 further includes a mirror 206, a confocal lens 207, a confocal stop 208, a condensing lens 209, and a photodetector 210 on the detection optical path (the transmission optical path of the dichroic mirror 203). . The signal output from the photodetector 210 is output to the A / D converter 211.

  The confocal lens 207 is a lens that collects fluorescence on the confocal stop 208. The confocal stop 208 is a stop disposed at a position optically conjugate with the focal plane of the objective lens 110. The confocal stop 208 is formed with a pinhole that transmits fluorescence generated from the focal position of the objective lens 110. The condenser lens 209 is a lens that guides the fluorescence that has passed through the confocal stop 208 to the photodetector 210.

  The photodetector 210 is a photomultiplier tube (PMT), for example, and outputs an analog signal corresponding to the amount of incident fluorescence. The A / D converter 211 converts the analog signal from the photodetector 210 into a digital signal (luminance signal) and outputs it to the arithmetic unit 20.

  In the microscope system according to this embodiment configured as described above, the microscope 200 scans the sample S with laser light using the scanning unit 204, and the fluorescence from each position of the sample S is detected by the photodetector 210. To detect. Then, the arithmetic unit 20 generates image data based on the digital signal (luminance signal) obtained by converting the signal from the photodetector 210 and the scanning information of the scanning unit 204. That is, in the microscope system according to the present embodiment, the microscope apparatus configured by the microscope 200 and the arithmetic unit 20 acquires the image data of the sample S.

  In the microscope system according to the present embodiment, the function calculation process illustrated in FIG. 4 and the processes illustrated in FIGS. 5, 11, and 12 can be performed in the same manner as the microscope system 1 according to the first embodiment. Therefore, a function for correcting spherical aberration can be calculated easily and with high accuracy. Also, the function can be calculated in a short time while suppressing damage to the sample S. Furthermore, the point that the spherical aberration correction process shown in FIG. 14 can be performed is the same as that of the microscope system 1 according to the first embodiment.

  FIG. 28 is a diagram illustrating the configuration of the microscope 300 according to the present embodiment. The microscope system according to the present embodiment is different from the microscope system 1 shown in FIG. 1 in that a microscope 300 is included instead of the microscope 100. Since the other points are the same as those of the microscope system 1, the same components are referred to by the same reference numerals.

  The microscope 300 is a normal fluorescence microscope that is not a scanning type. Note that the microscope 300 is also called a zoom microscope because it has a zoom function. The sample S is a biological sample such as a mouse brain, for example. As shown in FIG. 28, the microscope 300 includes a lamp house 301 including a light source 302, a collector lens 303, a fluorescent cube 304, a zoom lens 305, and an objective lens 110 on the illumination optical path. Note that the objective lens 110, the Z driving unit 109 that moves the objective lens 110 in the optical axis direction, and the correction ring 111 that is a correction device that corrects spherical aberration by moving the lens in the objective lens 110 are described in the first embodiment. This is the same as the microscope 100.

  The light source 302 is, for example, an LED light source or a high output mercury lamp. The output of the light source 302 is controlled by the light source control device 11. The collector lens 303 collimates the excitation light from the light source 302. The fluorescent cube 304 includes a dichroic mirror, an excitation filter, and an absorption filter (not shown). The fluorescent cube 304 is a light separation unit that separates excitation light and detection light (fluorescence) from the sample S, and separates excitation light and fluorescence according to wavelength.

  The zoom lens 305 is configured such that the distance between the lenses constituting the zoom lens 305 changes. The zoom magnification is changed by the zoom control device 12 changing the distance between the lenses by a motor or the like (not shown). That is, the zoom lens 305 is controlled by the zoom control device 12.

  The microscope 300 further includes an imaging lens 306 and an imaging device 307 on the detection optical path (the transmission optical path of the fluorescent cube 304). The imaging lens 306 condenses the fluorescence incident through the objective lens 110 and the zoom lens 305 on the imaging device 307 to form an optical image of the sample S. The imaging device 307 is, for example, a CCD camera, and captures an optical image of the sample S to generate image data of the sample S. The imaging device 307 outputs the generated image data to the arithmetic device 20. In the microscope system according to the present embodiment, the microscope apparatus that is the microscope 300 acquires the image data of the sample S.

  In the microscope system according to the present embodiment, the function calculation process illustrated in FIG. 4 and the processes illustrated in FIGS. 5, 11, and 12 can be performed in the same manner as the microscope system 1 according to the first embodiment. Therefore, a function for correcting spherical aberration can be calculated easily and with high accuracy. Also, the function can be calculated in a short time while suppressing damage to the sample S. Furthermore, the point that the spherical aberration correction process shown in FIG. 14 can be performed is the same as that of the microscope system 1 according to the first embodiment.

  The above-described embodiments are specific examples for facilitating understanding of the invention, and the present invention is not limited to these embodiments. The microscope system, the function calculation method, and the program can be variously modified and changed without departing from the concept of the present invention defined by the claims. Several features in the context of the individual embodiments described in this specification may be combined into a single embodiment.

  The configuration in which the Z control device 13 controls the Z driving unit 109 to change the Z position of the objective lens 110 has been exemplified. However, the Z control device 13 moves the microscope stage in the optical axis direction to move the objective lens 110. The Z position may be changed.

  In addition, the correction ring 111 is illustrated as a correction device that corrects the spherical aberration that varies depending on the depth of the observation target surface. However, the correction device may be any device that can change the amount of spherical aberration that occurs on the optical path. . The correction device may be, for example, a device using LCOS (Liquid crystal on silicon (trademark)), DFM (Deformable Mirror), a liquid lens, or the like. In addition, when the amount of generated spherical aberration is large and a single correction device cannot sufficiently correct spherical aberration, the amount of spherical aberration to be corrected is shared by a plurality of correction devices, and spherical aberration generated on the observation target surface May be corrected.

  In addition, when the pixel resolution is larger than the optical resolution, that is, when the pixel size calculated from the pixel resolution is larger than the distance between two points that can be optically identified, the generated spherical aberration is sufficient in the image data. It may not be reflected. In such a case, in order to correctly reflect the generated spherical aberration in the image data and thus in the evaluation value, the target value calculation process is executed with the zoom magnification increased so that the pixel resolution is smaller than the optical resolution. May be. Thereby, it is possible to calculate a set value for correcting the spherical aberration generated on the observation target surface with higher accuracy.

  In addition, as an example of a method for calculating an evaluation value, one image data is acquired for each set value, and an evaluation value is calculated for each acquired image data. However, a plurality of image data is acquired for each set value. Then, the evaluation value may be calculated from a plurality of image data using a Kalman filter or the like. According to such a method, the noise component included in each of the image data can be canceled by using a plurality of image data for each set value, so that a more accurate evaluation value can be calculated.

  In addition to the target value calculation processing shown in FIGS. 15 and 20, the target value calculation processing shown in FIGS. 18 and 22 also divides the entire area of the image data into a plurality of areas and evaluates each area. A value and a target value may be calculated. Thereby, the set value for correcting the spherical aberration can be calculated more correctly.

For example, when a biological sample such as a mouse brain is observed, cell bodies that emit bright light may be scattered on the surface to be observed. The brightness of such a cell body is greatly changed by the influence of the focus shift compared to the influence of the spherical aberration. For this reason, when an objective lens whose focal length changes according to the setting value of the correction ring 111 is used, it is difficult to appropriately calculate a setting value for correcting the spherical aberration by the evaluation value (image contrast). It may become. In such a case, as a method for calculating the evaluation value, a method shown in FIG. 29 in which the evaluation value is calculated after processing the image data may be employed.
FIG. 29 is a flowchart of processing for calculating an evaluation value after processing image data. Hereinafter, the evaluation value calculation process will be described with reference to FIG.

  The microscope system first creates a histogram relating to luminance values from image data (step S81). Here, the arithmetic unit 20 specifies the luminance value of each pixel constituting the image data, calculates the number of pixels for each luminance value, and creates a histogram relating to the luminance value. The histogram is created so that the user of the microscope can visually grasp the frequency distribution of luminance values. Therefore, the creation of a histogram may be omitted in the evaluation value calculation process.

  Next, the microscope system calculates an average luminance value from the image data (step S82). Here, the arithmetic unit 20 calculates the average luminance value by dividing the sum of the luminance values of a plurality of pixels constituting the image data by the number of pixels.

  Furthermore, the microscope system eliminates the influence of pixel data having high brightness (step S83). Here, the arithmetic unit 20 uses the histogram created in step S81 and the average luminance value calculated in step S82 to calculate, for example, 3σ (σ is the standard deviation of the luminance value of the pixels constituting the image data) from the average luminance value. Pixel data having high brightness exceeding that is specified, and the brightness value of those pixel data is changed to a predetermined brightness value to update the image data. The predetermined luminance value is, for example, an average luminance value + 3σ.

  Finally, the microscope system calculates an evaluation value of the image data based on the image data updated in step S83 (step S84). The evaluation value calculation method in this step is the same as the method described above.

  When the microscope system performs the process shown in FIG. 29, for example, the influence of cells that emit light brightly in the observation target surface can be eliminated. For this reason, the set value for correcting the spherical aberration can be calculated correctly. Note that the method of processing the image data is not limited to the method described above. For example, a range to be evaluated in the image may be specified on the displayed image, and an evaluation value may be calculated based on pixel data within the range. Also in this case, the setting value for correcting the spherical aberration can be correctly calculated by designating the range so as not to include cells that emit bright light.

DESCRIPTION OF SYMBOLS 1 Microscope system 10 Microscope control apparatus 11 Light source control apparatus 12 Zoom control apparatus 13 Z control apparatus 14 Correction ring control apparatus 20 Arithmetic apparatus 30 Display apparatus 40 Keyboard 50 Correction ring operation apparatus 60 Z drive part operation apparatuses 100, 200, 300 Microscope 101 , 201 Laser 102, 204 Scanning unit 103, 106, 205 Pupil projection optical system 104, 206 Mirror 105, 203 Dichroic mirror 107, 210 Photo detector 108, 211 A / D converter 109 Z drive unit 110 Objective lens 111 Correction ring 202 Beam expander 207 Confocal lens 208 Confocal stop 209 Condensing lens 301 Lamp house 302 Light source 303 Collector lens 304 Fluorescent cube 305 Zoom lens 306 Imaging lens 307 Imaging device S Sample CG Cover glass

Claims (5)

A microscope apparatus that includes an objective lens and a correction apparatus that corrects spherical aberration, and acquires image data of a sample in each of a plurality of states having different setting values of the correction apparatus for each Z position of the objective lens;
Based on a plurality of image data acquired for each Z position by the microscope apparatus, a target value at the Z position, which is a setting value of the correction apparatus for correcting spherical aberration, is calculated, and at least three Z positions and at least the at least based on the combination of the target value in the three Z positions, the function indicating the relationship between the Z position and the target value, e Bei and a calculation device for calculating by interpolation or function approximation,
The arithmetic unit is:
For each of two adjacent Z positions of the plurality of Z positions from which the microscope apparatus has acquired image data, based on the two Z positions and two target values consisting of target values at the two Z positions. Calculating the slope of the target value with respect to the Z position,
Determining the plurality of Z ranges based on slopes of target values for a plurality of Z positions, each comprising a slope of a target value for the Z positions calculated for each of the two Z positions;
A microscope system characterized in that, for each of the determined plurality of Z ranges, a partial function indicating a relationship between a Z position having the Z range as a domain and a target value is calculated by interpolation or function approximation. . The microscope system according to claim 1 , further comprising:
According to the Z position of the objective lens, a correction device control device is provided that changes a set value of the correction device to a target value calculated based on the Z position and a function calculated by the calculation device. Microscope system. The microscope system according to claim 1 or 2 ,
The microscope system according to claim 1, wherein the correction device is a correction ring that moves a lens in the objective lens. A method of calculating a function indicating a relationship between a Z position of an objective lens and a setting value of a correction device for correcting spherical aberration,
A microscope apparatus provided with the objective lens and the correction device that corrects spherical aberration acquires sample image data in each of a plurality of states with different setting values of the correction device for each Z position of the objective lens,
The arithmetic device calculates a target value at the Z position, which is a setting value of the correction device for correcting spherical aberration, based on a plurality of image data acquired for each Z position by the microscope device, and at least three Based on the combination of the Z position and the target value at the at least three Z positions, a function indicating the relationship between the Z position and the target value is calculated by interpolation or function approximation ,
Calculating the function is
For each of two adjacent Z positions of the plurality of Z positions from which the microscope apparatus has acquired image data, based on the two Z positions and two target values consisting of target values at the two Z positions. Calculating a slope of the target value with respect to the Z position;
Determining the plurality of Z ranges based on slopes of target values for a plurality of Z positions, each comprising slopes of target values for the Z positions calculated for each of the two Z positions;
For each of the determined plurality of Z ranges, calculating a partial function indicating a relationship between a Z position having the Z range as a domain and a target value by interpolation or function approximation. And how to. A microscope apparatus provided with an objective lens and a correction device for correcting spherical aberration is a plurality of sample image data acquired for each Z position of the objective lens, each acquired with different setting values of the correction device A process of calculating a target value at the Z position, which is a setting value of the correction device for correcting spherical aberration, based on the plurality of image data that has been corrected;
A function indicating the relationship between the Z position and the target value is calculated by interpolation or function approximation based on a combination of at least three Z positions from which the microscope apparatus has acquired image data and target values at the at least three Z positions. Processing,
For each of two adjacent Z positions of the plurality of Z positions from which the microscope apparatus has acquired image data, based on the two Z positions and two target values consisting of target values at the two Z positions. Calculating a slope of the target value with respect to the Z position;
Determining the plurality of Z ranges based on slopes of target values for a plurality of Z positions, each comprising slopes of target values for the Z positions calculated for each of the two Z positions;
For each of the determined plurality of Z ranges, calculating a partial function indicating the relationship between the Z position and the target value with the Z range as a domain by interpolation or function approximation,
Including processing,
A program characterized by causing a computer to execute the.