METHOD OF PROCESSING ION BEAM BASED ON OPTICAL MICROSCOPY IMAGING
20240112880 ยท 2024-04-04
Inventors
- Tao Xu (Beijing, CN)
- Wei Ji (Beijing, CN)
- Weixing LI (Beijing, CN)
- Jing Lu (Beijing, CN)
- Ke Xiao (Beijing, CN)
Cpc classification
International classification
Abstract
Provided is a method of ion beam processing based on optical microscopy imaging, including: marking a surface of a sample using the ion beam, so as obtain a registration reference pattern; performing a three-dimensional optical imaging on the sample to obtain a first three-dimensional light microscopy image; projecting the first three-dimensional light microscopy image to a cutting angle of the ion beam, and determining a first position of a to-be-researched target in the first three-dimensional light microscopy image based on the registration reference pattern; performing an ion beam imaging on the sample to obtain an image excited by the ion beam, and determining, according to the first position, a second position of the to-be-researched target in the image excited by the ion beam; and thinning the sample according to the second position to obtain a first slice containing the to-be-researched target.
Claims
1. A method of ion beam processing based on optical microscopy imaging, comprising: marking a surface of a sample using an ion beam, so as to obtain a registration reference pattern; performing a three-dimensional optical imaging on the sample to obtain a first three-dimensional light microscopy image; projecting the first three-dimensional light microscopy image to a cutting angle of the ion beam, and determining a first position of a to-be-researched target in the first three-dimensional light microscopy image based on the registration reference pattern; and performing an ion beam imaging on the sample to obtain an image excited by an ion beam, and determining, according to the first position, a second position of the to-be-researched target in the image excited by the ion beam.
2. The method according to claim 1, further comprising: thinning the sample according to the second position to obtain a first slice containing the to-be-researched target.
3. The method according to claim 1, further comprising: thinning the sample according to the second position to obtain a second slice containing the to-be-researched target; performing a three-dimensional optical imaging on the second slice to obtain a second three-dimensional light microscopy image, wherein a magnification of the three-dimensional optical imaging on the second slice is greater than a magnification of the three-dimensional optical imaging on the sample; projecting the second three-dimensional light microscopy image to the cutting angle of the ion beam to obtain a two-dimensional projection image; determining a third position of the to-be-researched target in the second slice based on the two-dimensional projection image; and thinning the sample according to the third position to obtain a third slice containing the to-be-researched target.
4. The method according to claim 3, wherein the performing a three-dimensional optical imaging on the sample or the performing a three-dimensional optical imaging on the second slice comprises: loading the sample or the second slice onto a light microscopy imaging position in an electron microscopy vacuum chamber, so as to keep the sample horizontal; and performing, in a direction perpendicular to the sample, a multi-channel three-dimensional imaging on the sample or the second slice by using a three-dimensional optical imaging technology.
5. The method according to claim 4, wherein the three-dimensional optical imaging technology comprises a confocal imaging method, a structured light illumination imaging method, a three-dimensional single molecule localization imaging method, or a light sheet imaging method.
6. The method according to claim 4, wherein an image of the registration reference pattern or a slice surface morphology information is obtained using a bright field imaging, and an image of the to-be-researched target is obtained using a fluorescence imaging.
7. The method according to claim 3, wherein the projecting the first three-dimensional light microscopy image to a cutting angle of the ion beam or the projecting the second three-dimensional light microscopy image to the cutting angle of the ion beam to obtain a two-dimensional projection image comprises: projecting the first three-dimensional light microscopy image and the second three-dimensional light microscopy image to the two-dimensional projection image with a same viewing angle as the ion beam.
8. The method according to claim 7, wherein the determining a first position of a to-be-researched target in the first three-dimensional light microscopy image based on the registration reference pattern comprises: measuring a two-dimensional pixel distance from the to-be-researched target in the two-dimensional projection image to a center of the registration reference pattern; converting the two-dimensional pixel distance to a true distance based on a pre-calibrated optical imaging pixel point size; and determining the first position based on the true distance.
9. The method according to claim 2, wherein a thickness of the first slice is at a level of one hundred nanometers, and the first slice is suitable for a transmission electron imaging or an electron tomography imaging.
10. The method according to claim 3, wherein a thickness of the third slice is at a level of one hundred nanometers, the third slice is suitable for a transmission electron imaging or an electron tomography imaging, and a thickness of the second slice is at a level of micrometers.
11. The method according to claim 2, further comprising: performing the three-dimensional optical imaging on the first slice to obtain a third three-dimensional light microscopy image; analyzing the third three-dimensional light microscopy image and extracting a type information and a distribution information of the to-be-researched target in the first slice; and guiding and assisting in a collection and an analysis of cryo-electron tomography imaging data based on the type information and the distribution information of the to-be-researched target.
12. The method according to claim 9, wherein guiding and assisting in a collection and an analysis of cryo-electron tomography imaging data based on the type information and the distribution information of the to-be-researched target comprises: performing a transmission electron imaging on the first slice to obtain a transmission electron microscopy image; locating a fourth position of the to-be-researched target in the transmission electron microscopy image based on the type information and the distribution information of the to-be-researched target; delineating a collection range of the cryo-electron tomography imaging data in the transmission electron microscopy image based on the fourth position; and associating a three-dimensional reconstructed cryo-electron tomography image with the corresponding third three-dimensional light microscopy image of the first slice, and distinguishing a type and a position of the researched target using a fluorescence information, so as to assist in an analysis of a cryo-electron tomography image.
13. The method according to claim 3, further comprising: performing the three-dimensional optical imaging on the third slice to obtain a third three-dimensional light microscopy image; analyzing the third three-dimensional light microscopy image and extracting a type information and a distribution information of the to-be-researched target in the third slice; and guiding and assisting in a collection and an analysis of cryo-electron tomography imaging data based on the type information and the distribution information of the to-be-researched target.
14. The method according to claim 13, wherein the guiding and assisting in a collection and an analysis of cryo-electron tomography imaging data based on the type information and the distribution information of the to-be-researched target comprises: performing a transmission electron imaging on the third slice to obtain a transmission electron microscopy image; locating a fourth position of the to-be-researched target in the transmission electron microscopy image based on the type information and the distribution information of the to-be-researched target; delineating a collection range of the cryo-electron tomography imaging data in the transmission electron microscopy image based on the fourth position; and associating a three-dimensional reconstructed cryo-electron tomography image with the corresponding third three-dimensional light microscopy image of the third slice, and distinguishing a type and a position of the researched target using a fluorescence information, so as to assist in an analysis of a cryo-electron tomography image.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0019]
[0020]
[0021]
[0022]
[0023]
[0024]
DESCRIPTION OF SYMBOLS
[0025] 1ion beam module; 2scanning electron microscopy module; 3optical objective module; 4optical window; 5optical excitation imaging module; 6electron microscopy imaging cutting position; 7light microscopy imaging position; 8vacuum chamber.
DETAILED DESCRIPTION OF EMBODIMENTS
[0026] In order to make objectives, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in details below with reference to specific embodiments and accompanying drawings. Obviously, the described embodiments are some, but not all of embodiments of the present disclosure. Based on embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without any creative work fall within the scope of protection of the present disclosure.
[0027] Terms used herein are only intended to describe specific embodiments and are not intended to limit the present disclosure. Terms include, comprise, contain, etc. used herein indicate the presence of the described features, steps, operations and/or components, but do not exclude the presence or addition of one or more other features, steps, operations and/or components.
[0028] In the present disclosure, unless otherwise specified and limited, terms installation, coupling, connection, fixation, etc. should be broadly understood, for example, they may include a fixed connection, a detachable connection, or an integration; they may include a mechanical connection, an electrical connection or a communication with each other; they may include a direct connection or an indirect connection through an intermediate medium, which may be an internal connection between two components or an interaction relationship between two components. For those skilled in the art, specific meanings of the above-mentioned terms in the present disclosure may be understood based on specific circumstances.
[0029] In the descriptions of the present disclosure, it should be understood that orientation or positional relationships indicated by terms longitudinal, length, circumferential, front, back, left, right, top, bottom, inside, outside, etc. are orientation or positional relationships shown in the accompanying drawings, which is only for convenience of describing the present disclosure and simplifying the description, and does not indicate or imply that the subsystem or component referred to must have a particular orientation or be constructed and operated in a particular orientation. Therefore, the above-mentioned terms may not be construed as limiting the present disclosure.
[0030] Throughout the accompanying drawings, the same elements are indicated by the same or similar reference numerals. When it may cause confusion in the understanding of the present disclosure, conventional structures or configurations may be omitted. The shapes, sizes, and positional relationships of components in the drawings do not reflect actual size, ratios, and actual positional relationships.
[0031] Similarly, in order to simplify the present disclosure and help understand one or more aspects in the present disclosure, in the above-mentioned descriptions of exemplary embodiments of the present disclosure, various features of the present disclosure are sometimes grouped together into a single embodiment, drawing, or description thereof. The descriptions of reference terms an embodiment, some embodiments, an example, a specific example, or some examples mean that specific features, structures, materials, or characteristics described in combination with the embodiment(s) or example(s) are included in at least one embodiment or example of the present disclosure. In the specification, schematic expressions of the above-mentioned terms do not necessarily refer to the same embodiment(s) or example(s). Moreover, the described specific features, structures, materials, or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.
[0032] In addition, terms first and second are only used to describe the purpose, and may not be construed as indicating or implying relative importance or implying a quantity of technical features indicated. Therefore, features limited by first and second may explicitly or implicitly include one or more of the features. In the descriptions of the present disclosure, multiple means at least two, such as two, three, etc., unless otherwise specifically defined.
[0033]
[0034] As shown in
[0035] In operation S100, a surface of a sample is marked using an ion beam, so as to obtain a registration reference pattern.
[0036] In an embodiment of the present disclosure, the sample may be pre-loaded onto an electron microscopy imaging position in an electron microscopy chamber and tilted to a cutting angle, and then the surface of the sample may be marked using the ion beam, so as to obtain the registration reference pattern. For example, the means of marking may be etching. The ion beam may be a focused ion beam, a plasma beam, or a sub ion beam, etc. A specific type of the ion beam may be selected according to actual requirements, which will not be limited in the present disclosure. The cutting angle may be any value allowed by an electron microscopy system and may be set according to actual application requirements, which will not be limited in the present disclosure.
[0037] In embodiments of the present disclosure, a shape of the registration reference pattern may be a variety of shapes, as long as the shape may effectively function as a reference, which will not be limited in the present disclosure.
[0038]
[0039] As shown in
[0040] In operation S1101, a three-dimensional optical imaging is performed on the sample to obtain a first three-dimensional light microscopy image.
[0041] In an embodiment of the present disclosure, first, the sample loaded in an electron microscopy vacuum chamber is placed at a light microscopy imaging position to keep the sample horizontal. Then, in a direction perpendicular to the sample, a multi-channel three-dimensional imaging is performed by using a three-dimensional optical imaging technology, and an imaging area covers an etched registration reference pattern and a to-be-researched target.
[0042]
[0043] As shown in
[0044] It should be understood that the three-dimensional optical imaging technology may be any optical imaging technology that may achieve three-dimensional imaging.
[0045] In an embodiment of the present disclosure, the three-dimensional optical imaging technology may include a confocal imaging method or a structured light illumination imaging method or a three-dimensional single molecule localization imaging method or a light sheet imaging method. For example, in a process of the three-dimensional imaging, a bright field and a fluorescence signal obtained by scanning different layers of the sample may be detected based on an embedded confocal microscope. An image of the registration reference pattern may be obtained using a bright field imaging, and an image of the to-be-researched target may be obtained using a fluorescence imaging.
[0046] In operation S1201, the first three-dimensional light microscopy image is projected to a cutting angle of the ion beam, and a first position of a to-be-researched target in the first three-dimensional light microscopy image is determined based on the registration reference pattern.
[0047] In embodiments of the present disclosure, the first three-dimensional light microscopy image taken in the direction perpendicular to the sample may be projected to a cutting angle of the ion beam to obtain a two-dimensional projection image with a same viewing angle as the ion beam.
[0048]
[0049] As shown in
[0050] In operation S1301, an ion beam imaging is performed on the sample to obtain an image excited by an ion beam, and a second position of the to-be-researched target in the image excited by the ion beam is determined according to the first position.
[0051] In an embodiment of the present disclosure, first, the sample loaded in the electron microscopy vacuum chamber is moved from the light microscopy imaging position to the electron microscopy imaging position, the sample is tilted to the cutting angle, and the ion beam imaging is performed on the sample. The imaging area covers the registration reference pattern and the researched target.
[0052]
[0053] As shown in
[0054] In operation S140, the sample is thinned according to the second position to obtain a first slice containing the to-be-researched target.
[0055] In an embodiment of the present disclosure, the sample is tilted to the cutting angle, and the sample is thinned according to the second position of the to-be-researched target in the electron image excited by the ion beam determined in operation S130 to finally acquire the first slice containing the to-be-researched target. The first slice is suitable for a transmission electron imaging and an electron tomography imaging.
[0056]
[0057] As shown in
[0058] According to embodiments of the present disclosure, a positioning accuracy of the method of processing the ion beam based on the optical microscopy imaging described in operations S100 to S140 is applicable to a research target with a larger size.
[0059]
[0060] As shown in
[0061] In operation S240, the sample is thinned according to the second position to obtain a second slice containing the to-be-researched target.
[0062] In an embodiment of the present disclosure, the sample is tilted to the cutting angle, and the sample is thinned according to the second position of the to-be-researched target in the image excited by the ion beam determined in operation S230 to obtain the second slice containing the to-be-researched target. Operation S240 is a coarse thinning. Therefore, a thickness of the second slice may be at a level of micrometers for a subsequent further fine thinning.
[0063]
[0064] As shown in
[0065] In operation S250, the three-dimensional optical imaging is performed on the second slice to obtain a second three-dimensional light microscopy image.
[0066] In an embodiment of the present disclosure, first, the second slice is loaded into the light microscopy imaging position in the electron microscopy vacuum chamber to keep the sample horizontal. Then, in the direction perpendicular to the sample, the multi-channel three-dimensional imaging is performed on the second slice using the three-dimensional optical imaging technology. A magnification of the three-dimensional optical imaging on the second slice may be greater than a magnification of the three-dimensional optical imaging on the sample. An imaging range does not need to include the registration reference pattern, so that the second slice may almost fill the imaging area, which may be beneficial to improve an imaging accuracy and an imaging speed.
[0067] In an embodiment of the present disclosure, the three-dimensional optical imaging technology may include a confocal imaging method or a structured light illumination imaging method or a three-dimensional single molecule localization imaging method or a light sheet imaging method. For example, in the process of the three-dimensional imaging, the bright field and the fluorescence signal obtained by scanning different layers of the sample may be detected based on the embedded confocal microscope. A surface morphology information of the slice may be obtained using the bright field imaging, and the image of the to-be-researched target may be obtained using the fluorescence imaging.
[0068] In operation S260, the second three-dimensional light microscopy image is projected to the cutting angle of the ion beam to obtain a two-dimensional projection image, and a third position of the to-be-researched target in the second slice is determined based on the two-dimensional projection image.
[0069] In an embodiment of the present disclosure, the two-dimensional projection image obtained by projecting the second three-dimensional light microscopy image to the cutting angle of the ion beam further contains a surface morphology information of the second slice obtained by the bright field imaging. The third position of the to-be-researched target in the second slice may be determined by an artificial recognition, an image fitting, etc. according to the surface morphology information of the second slice included in the two-dimensional projection image. A positioning accuracy of operation S260 is greater than the positioning accuracy of operation S1301, which may accurately locate nanoscale targets such as an organelle, a subcellular structure, etc.
[0070] In operation S270, the sample is thinned according to the third position to obtain a third slice containing the to-be-researched target.
[0071] In an embodiment of the present disclosure, the sample is tilted to the cutting angle, and the sample is thinned according to the third position of the to-be-researched target in the second slice determined by operation S260 to finally acquire the third slice containing the to-be-researched target. An image of the third slice obtained is similar to the image of the first slice shown in
[0072] According to embodiments of the present disclosure, the method of processing the ion beam based on the optical microscopic imaging described in operations S200 to S270 is applicable to research targets with a smaller size, such as an organelle, a subcellular structure and other nanoscale research targets.
[0073]
[0074] As shown in
[0075] In operation S150, the three-dimensional optical imaging is performed on the first slice to obtain a third three-dimensional light microscopy image, and the third three-dimensional light microscopy image is analyzed and a type information and a distribution information of the to-be-researched target in the first slice are extracted.
[0076] In an embodiment of the present disclosure, the first slice is placed at a light microscopy imaging position in an electron microscopy vacuum chamber, and in a direction perpendicular to the sample, a three-dimensional multi-channel optical imaging may be performed on the first slice using a three-dimensional optical imaging technology so as to obtain information such as a type, a distribution, etc. of the to-be-researched target in the first slice. The three-dimensional optical imaging technology may include a confocal imaging method or a structured light illumination imaging method or a three-dimensional single molecule localization imaging method or a light sheet imaging method.
[0077] In operation S160, a collection and an analysis of cryo-electron tomography imaging data are guided and assisted in based on the type information and the distribution information of the to-be-researched target in the third three-dimensional light microscopy image.
[0078] In an embodiment of the present disclosure, the first slice is transferred to a transmission electron microscopy for a transmission electron imaging, and then a transmission electron microscopy image is associated with a corresponding third three-dimensional light microscopy image. That is, a fourth position of the researched target in the transmission electron microscopy image may be located through a light microscopy information. A collection range of the cryo-electron tomography imaging data may be delineated in the transmission electron microscopy image based on the fourth position. A three-dimensional reconstructed cryo-electron tomography image may also be associated with a corresponding third three-dimensional light microscopy image of the first slice, a type and a position of the researched target may be distinguished using a fluorescence information, so as to assist in an analysis of a cryo-electron tomography image.
[0079]
[0080] As shown in
[0081] In operation S280, the three-dimensional optical imaging is performed on the third slice to obtain a third three-dimensional light microscopy image, and the third three-dimensional light microscopy image is analyzed and a type information and a distribution information of the to-be-researched target in the third slice are extracted.
[0082] In an embodiment of the present disclosure, the third slice is placed at the light microscopy imaging position in the electron microscopy vacuum chamber, and in the direction perpendicular to the sample, the three-dimensional multi-channel optical imaging is performed on the third slice using the three-dimensional optical imaging technology so as to obtain information such as a type, a distribution, etc. of the to-be-researched target in the third slice. The three-dimensional optical imaging technology may include a confocal imaging method or a structured light illumination imaging method or a three-dimensional single molecule localization imaging method or a light sheet imaging method.
[0083] In operation S290, a collection and an analysis of cryo-electron tomography imaging data are guided and assisted in based on the type information and the distribution information of the to-be-researched target in the third three-dimensional light microscopy image.
[0084] In an embodiment of the present disclosure, the third slice is transferred to a transmission electron microscopy for a transmission electron imaging, and then a transmission electron microscopy image is associated with a corresponding third three-dimensional light microscopy image. That is, a fourth position of the researched target in the transmission electron microscopy image may be located through a light microscopy information. A collection range of the cryo-electron tomography imaging data may be delineated in the transmission electron microscopy image based on the fourth position. A three-dimensional reconstructed cryo-electron tomography image may also be associated with a corresponding third three-dimensional light microscopy image of the first slice, a type and a position of the researched target may be distinguished using a fluorescence information, so as to assist in an analysis of a cryo-electron tomography image.
[0085]
[0086] As shown in
[0087] an ion beam module 1, a scanning electron microscopy module 2, an optical objective module 3, an optical window 4, an optical excitation imaging module 5, an electron microscopy imaging cutting position 6, a light microscopy imaging position 7, and a vacuum chamber 8.
[0088] The ion beam module 1, the scanning electron microscopy module 2, and the optical objective module 3 may be provided inside the same vacuum chamber 8. The optical window 4 is provided on a sidewall of the vacuum chamber 8 and is in an optical path communication with the optical objective module 3 and the optical excitation imaging module 5. The electron microscopy imaging cutting position 6 is provided below the ion beam module 1 and the scanning electron microscopy module 2, and the light microscopy imaging position 7 is provided below the optical objective module 3. The sample may be switched between the electron microscopy imaging cutting position 6 and the light microscopy imaging position 7.
[0089] The ion beam module 1 is used for an ion beam cutting of the sample, the scanning electron microscopy module 2 is used for a scanning electron microscopy imaging of the sample, the optical window 4 is used to be connected to optical paths inside and outside the vacuum chamber 8, the optical excitation imaging module 5 is used to provide scanning excitation light for confocal imaging, and transmit the excitation light to the sample through the optical objective module 3. A three-dimensional imaging may be achieved by scanning different layers of the sample. At the same time, the optical excitation imaging module 5 is also used to detect a bright field signal and a fluorescence signal collected by the optical objective module 3, and an image is collected by a computer.
[0090] It should be noted that the embedded three-dimensional optoelectronic correlation imaging apparatus of the above-mentioned structure is only a structure capable of implementing the method of processing the ion beam provided by embodiments of the present disclosure, and is not intended to limit the method of processing the ion beam provided by the present disclosure.
[0091] In summary, a registration process provided by embodiments of the present disclosure adopts a photoelectric correlation registration, which may directly etch the surface of the sample using the ion beam so as to acquire the registration reference pattern for registration without adding a fiducial marker, so that a complexity of an experiment may be reduced and an operation may be simple and have a high repeatability. The optoelectronic correlation registration may be performed using a three-dimensional light microscopy image projection and the registration reference pattern etched by the ion beam, which may further reduce the complexity and enhance a repeatability of a registration result. Further, a position of a target in a slice may be determined using the three-dimensional light microscopy image projection, which may have a high positioning accuracy and may achieve fixed-point cutting with a nano precision. In addition, a type of the target may be identified and the position of the target in the slice may be determined by using the three-dimensional light microscopy image of a final slice. The information may be used to assist in the collection and the analysis of the cryo-electron tomography imaging data.
[0092] The method of processing the ion beam based on the optical microscopy imaging provided by embodiments of the present disclosure includes at least the following advantages:
[0093] A registration process adopts a photoelectric correlation registration, which may directly etch the surface of the sample using the ion beam so as to acquire the registration reference pattern for registration without adding a fiducial marker, so that a complexity of an experiment may be reduced and an operation may be simple and have a high repeatability. The optoelectronic correlation registration may be performed using a three-dimensional light microscopy image projection and the registration reference pattern etched by the ion beam, which may further reduce the complexity and enhance a repeatability of a registration result.
[0094] Further, a position of a target in a slice may be determined using the three-dimensional light microscopy image projection, which may have a high positioning accuracy and may achieve fixed-point cutting with a nano precision.
[0095] In addition, a type of the target may be identified and the position of the target in the slice may be determined by using the three-dimensional light microscopy image of a final slice. The information may be used to assist in the collection and the analysis of the cryo-electron tomography imaging data.
[0096] The above-mentioned specific embodiments have described in detail the objectives, technical solutions and advantages of the present disclosure. It should be noted that the above are only specific embodiments of the present disclosure and are not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, and the like made within the spirit and scope of the present disclosure shall be included in the scope of protection of the present disclosure.