Microscope support
By combining coarse and fine drive devices in the microscope holder, the contradiction between long stroke and high precision in the prior art is resolved, and efficient automatic focusing and image acquisition of the microscope are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- LEICA INSTRUMENTS (SINGAPORE) PTE LTD
- Filing Date
- 2024-06-17
- Publication Date
- 2026-05-05
AI Technical Summary
Existing Z-drive mechanisms for microscopes present a trade-off between achieving long travel distances and high positioning accuracy, resulting in poor performance, particularly in the autofocus and image acquisition functions of digital microscopes, where functional limitations exist.
A combination of coarse and fine drive devices is used. The coarse drive device is used for rapid, long-distance movement, while the fine drive device is used for precise positioning. The focal plane position is adjusted with high precision through coordinated control by a controller.
It achieves high precision while providing fast movement speed and long travel distance, improving the efficiency and user-friendliness of the microscope, especially in the process of autofocus and image acquisition.
Smart Images
Figure CN121986284A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a microscope stand, which includes a base and a microscope column extending vertically from the base. Background Technology
[0002] In this art, drive mechanisms for microscopes are known that move samples and / or detection optics along the optical axis of the microscope. Since the optical axis is also called the Z-axis, these drive mechanisms are also called Z-drive mechanisms. These Z-drive mechanisms are capable of moving the focal plane position of the microscope relative to the sample in order to precisely align the focal plane position with the desired sample position. Due to the small depth of field of typical microscopes, high precision is required when adjusting the focal plane position. However, samples may extend along the Z-direction. Therefore, Z-drive mechanisms also require a relatively long travel distance to enable observation of thick samples.
[0003] Known Z-drive mechanisms include manual and electric Z-drive mechanisms. In a manual Z-drive mechanism, the movement of a control element (often called a focusing knob) is directly translated into movement of the sample or inspection optics. A microscope may include two focusing knobs: one for coarse focusing and a second for fine focusing. In an electric Z-drive mechanism, the movement of the control element controls a motor that moves the sample or inspection optics. Electric Z-drive mechanisms enable autofocus and allow for automated image acquisition, particularly Z-axis tomographic and depth-of-field extended images, thus greatly supporting digital image acquisition. Known electric Z-drive mechanisms include a single motor, typically a stepper motor or a DC motor. However, Z-drive mechanisms incorporating piezoelectric motors also exist for very fine adjustment of the sample or inspection optics position.
[0004] The main drawback of existing technologies is their poor overall performance, stemming from the need for both long travel distances and rapid movement, as well as high positioning accuracy. High positioning accuracy is typically achieved using motor-gear units with large reduction ratios, but this results in slow movement speeds. Conversely, small reduction ratios achieve high movement speeds, but positioning accuracy is proportionally reduced. Therefore, known existing technologies are in a technical dilemma, leading to functional limitations, particularly for digital microscopes. Summary of the Invention
[0005] The aim is to provide a microscope stand that allows for high-precision adjustment of the focal plane position while providing a long travel distance and fast movement speed.
[0006] The above objectives are achieved by the subject matter of the independent claims. Advantageous embodiments are defined in the dependent claims and the following description.
[0007] The proposed microscope support includes a base and a microscope column extending vertically from the base, the base having an observation position configured to receive an object. An imaging unit carrier is movably mounted to the microscope column and configured to mount the imaging unit to the microscope support. The imaging unit is configured to generate a microscopic image of the object received in the observation position. The microscope column also includes a coarse drive mechanism and a fine drive mechanism mechanically coupled to and arranged in series with the coarse drive mechanism, the coarse drive mechanism being configured to coarsely adjust the vertical position of the imaging unit carrier along the vertical direction. The fine drive mechanism is configured to finely adjust the vertical position of the imaging unit carrier along the vertical direction. The coarse drive mechanism is arranged and configured to be movable via the fine drive mechanism, and the fine drive mechanism is configured to move the coarse drive mechanism and the imaging unit carrier along the vertical direction to finely adjust the vertical position of the imaging unit carrier.
[0008] The base may include, for example, a transmitted light stage. However, the base may also include any other arrangement that allows the sample to be placed in the observation position. A microscope column extends vertically from the base and mounts an imaging unit carrier, which can be moved vertically. The imaging unit carrier mounts an imaging unit, which is not part of the microscope support. The microscope support and the imaging unit together form at least part of the microscope system. The imaging unit is detachable from the imaging unit carrier and includes optical components for generating microscopic images. The imaging unit may also include an imaging sensor for capturing microscopic images and / or an eyepiece that allows the user to observe the microscopic images. A fine drive mechanism is configured to move the imaging unit carrier in small steps. This allows the imaging unit carrier to be moved with high precision, for example, during autofocus or acquisition of Z-axis tomographic images. Conversely, a coarse drive mechanism is configured to move the imaging unit carrier in larger steps than the fine drive mechanism. Therefore, the coarse drive mechanism allows the imaging unit carrier to move rapidly over large distances. The coarse and / or fine drive mechanisms may be electrically powered. The coarse and fine drive mechanisms are mechanically coupled and arranged in series. Specifically, the imaging unit carrier is moved directly by the coarse drive mechanism to roughly position the imaging unit mounted on it. The coarse drive mechanism itself is attached to the fine drive mechanism, allowing the fine drive mechanism to move both the coarse drive mechanism and the imaging unit carrier in a linear motion along the vertical direction for precise positioning of the imaging unit. Therefore, the coarse and fine drive mechanisms together form a single drive unit for the microscope support, allowing for high-precision adjustment of the imaging unit carrier's position, and consequently, high-precision adjustment of the imaging unit and focal plane positions, while also providing long stroke and fast traverse speed.
[0009] In another embodiment, the microscope stand includes a controller configured to control coarse and fine drive mechanisms based on user input corresponding to a vertical position setting of the imaging unit carrier along the vertical direction. Specifically, the controller is configured to control the coarse and fine drive mechanisms based on a single user input. Based on the user input, the controller determines how to move the imaging unit carrier to position the imaging unit at a specified vertical position. For example, the controller may first control the coarse drive mechanism to quickly bring the imaging unit carrier approximately to the specified vertical position, and then control the fine drive mechanism to precisely position the imaging unit carrier at the specified vertical position. Unlike prior art where fine and coarse adjustments require different user inputs, this embodiment allows the user to specify the vertical position of the imaging unit carrier with a single input. This makes the microscope stand very user-friendly.
[0010] In another embodiment, the microscope support includes a linear encoder configured to generate a sensor signal corresponding to the vertical position of the imaging unit carrier along the vertical direction and to transmit this sensor signal to a controller. Alternatively, the vertical position of the imaging unit carrier can be determined by alternative means, such as laser distance measurement. The sensor signal allows the controller to accurately determine the actual vertical position of the imaging unit carrier, thereby allowing for more precise control of the vertical position.
[0011] In another embodiment, the controller is a closed-loop controller configured to control the coarse and fine drive units based on sensor signals. When controlling the coarse and fine drive units to move the imaging unit carrier, the closed-loop controller compares the setpoint with the actual vertical position of the imaging unit carrier and corrects for deviations (e.g., deviations due to clearance). This allows for more precise control over extended use, as clearance caused by wear is automatically compensated for.
[0012] In another embodiment, the stroke of the fine drive is less than that of the coarse drive. Since the fine drive is used for precise positioning and the coarse drive is used for long travel distances, the stroke of the fine drive can be much smaller than that of the coarse drive. This allows for more efficient use of both the fine and coarse drives.
[0013] In another embodiment, the stroke of the coarse drive is at least 5 mm and / or at most 2000 mm. This range of motion is optimal for approximate positioning of the imaging unit in many microscopic applications.
[0014] In another embodiment, the travel of the precision actuation device is at least 1 micrometer and / or at most 500 micrometers. This range of motion is optimal for precise positioning of imaging units in many microscopic applications.
[0015] In another embodiment, the step size of the fine drive is smaller than that of the coarse drive. The step size is the minimum vertical movement that each drive can achieve. Since the fine drive is used for precise positioning and the coarse drive is used for long travel distances, the step size of the coarse drive can be larger than that of the fine drive, thus allowing for more efficient use of both the fine and coarse drive devices.
[0016] In another embodiment, the step size of the fine actuation device is at least 1 nanometer and / or at most 1000 nanometers. This step size is optimal for approximate positioning of imaging units in many microscopic applications.
[0017] In another embodiment, the coarse drive is a spindle drive, a rack and pinion drive, or a belt drive. These drive mechanisms are particularly suitable for rapidly moving heavy loads (e.g., imaging units) over long distances. Therefore, they are well-suited as coarse drive mechanisms.
[0018] In another embodiment, the coarse drive includes a stepper motor, a DC motor, a brushless DC motor, or a linear motor. These motors are well-suited for rapidly moving heavy loads. Therefore, they are well-suited for driving coarse drives.
[0019] In another embodiment, the precision actuation device includes a piezoelectric motor or a stepper motor. These motors are particularly well-suited for small-step movements and even heavy loads. Therefore, they are ideally suited for using precision actuation devices to accurately position imaging units.
[0020] In another embodiment, the base includes a microscope stage configured to be movable in at least one direction perpendicular to the vertical. The top surface of the microscope stage includes an observation position. The movable microscope stage allows a sample received at the observation position to move within the field of view of the imaging unit. Preferably, the microscope stage is configured to be movable in two directions perpendicular to the vertical. In such an embodiment, the microscope stage is an XY platform. Attached Figure Description
[0021] Specific embodiments are described below with reference to the accompanying drawings, wherein:
[0022] Figure 1 This is a schematic diagram of a microscope system with a microscope stand according to an embodiment;
[0023] Figure 2 It is based on Figure 1 A schematic cross-sectional view of the microscope stand; and
[0024] Figure 3 It is based on Figure 1 A block diagram of the microscope system. Detailed Implementation
[0025] Figure 1 This is a schematic diagram of a microscope system 100 with a microscope support 102 according to an embodiment.
[0026] The microscope system 100 includes a microscope stand 102, an imaging unit 104 mounted on the microscope stand 102, and a controller 106. The imaging unit 104 is configured to generate a microscopic image of an object 108 and may include optical elements, such as objectives and tube lenses, for generating the microscopic image of the object 108. Figure 1 In this embodiment, imaging unit 104 is exemplaryly configured as a digital microscope, which includes an image sensor for capturing microscopic images. However, imaging unit 104 may also include at least one eyepiece to allow a user to directly observe the microscopic images generated by the optical elements of imaging unit 104. Imaging unit 104 may also be detachable to allow a user to replace imaging unit 104 with a different imaging unit.
[0027] The microscope stand 102 includes a base 110 located at the bottom of the microscope stand 102. The base 110 exemplarily includes a microscope stage 112. An observation position 114 for receiving an object 108 is arranged on the top surface of the microscope stage 112. The microscope stage 112 is further configured to be movable in two directions perpendicular to the optical axis O of the imaging unit 104. Since the optical axis O is also called the Z-axis, these two vertical directions are respectively called the x-axis and y-axis. Therefore, according to... Figure 1 The microscope stage 112 of the illustrated embodiment is also referred to as the xy platform. The movable microscope stage 112 allows the object 108 received in the observation position 114 to be moved into the field of view of the imaging unit 104.
[0028] The microscope stand 102 further includes a microscope column 116 extending from the base 110 in a vertical direction V. Figure 1 In the illustrated embodiment, the vertical direction V is parallel to the optical axis O of the imaging unit 104. The microscope column 116 includes an imaging unit carrier 118 configured to mount the imaging unit 104. The imaging unit carrier 118 is movable along the vertical direction V. This allows the imaging unit 104 mounted on the imaging unit carrier 118 to be positioned along the vertical direction V, thereby positioning it relative to the object 108 along its optical axis O. By moving the imaging unit 104 along the vertical direction V, the focal plane position of the imaging unit 104 also moves. Therefore, moving the imaging unit carrier 118 also moves the focal plane position of the imaging unit 104.
[0029] The movement of the imaging unit carrier 118 is facilitated by two driving devices 302, 304 forming the driving unit 300 (see...). Figure 3 (The following will be a reference) Figure 2The drive unit 300 is controlled by the controller 106 of the microscope system 100, which will be described below with reference to... Figure 3 This will be described in more detail. The controller 106 is further exemplarily configured to control the imaging unit 104 and the microscope stage 112, and may be part of the microscope support 102.
[0030] Figure 2 It is based on Figure 1 A schematic cross-sectional view of the microscope stand 102.
[0031] from Figure 2 As can be seen, the microscope column 116 houses a threaded spindle 200, which extends in the vertical direction V almost the entire length of the microscope column 116. The spindle 200 is rotatably mounted at the bottom of the microscope column 116 via a spindle bearing 202. A rotary motor 204, such as a stepper motor or a DC motor, is arranged on top of the spindle 200 and configured to rotate the spindle 200. The imaging unit carrier 118 engages with the threads of the spindle 200 and can therefore be moved by rotating the spindle 200. At least the spindle 200 and the rotary motor 204 form a coarse drive 302 (see...). Figure 3 The coarse drive device 302 is used to roughly position the imaging unit carrier 118 along the vertical direction V, and then position the imaging unit 104. The step size of the coarse drive device 302, that is, the minimum amount of movement along the vertical direction V that the coarse drive device 302 can achieve, is determined by the step size of the rotary motor 204 and the lead of the thread of the spindle. In an alternative embodiment, the coarse drive device 302 may also be a rack and pinion drive device or a belt drive device.
[0032] exist Figure 2 In the illustrated embodiment, the spindle bearing 202 is arranged on top of the piezoelectric motor 206. The piezoelectric motor 206 forms the precision drive device 304 (see...). Figure 3 The coarse actuation device 304 allows both the coarse actuation device 302 and the imaging unit carrier 118 to move linearly along the vertical direction V. The step size of the fine actuation device 304 is much smaller than that of the coarse actuation device 302. Therefore, the fine actuation device 304 allows the imaging unit carrier 118, and consequently the imaging unit 104, to be precisely positioned along the vertical direction V. For example, the step size of the coarse actuation device 302 can be between 0.1 micrometers and 10 micrometers, while the step size of the fine actuation device 304 can be between 1 nanometer and 1000 nanometers.
[0033] The coarse drive device 302 and the fine drive device 304 form the drive unit 300 of the microscope support 102 (see...). Figure 3At least a portion of the drive unit 300 enables the imaging unit carrier 118 to be positioned vertically in the direction V. The coarse drive unit 302, due to its larger step size, allows for rapid movement of the imaging unit carrier 118 over long distances. The fine drive unit 304, due to its much smaller step size, allows for high-precision positioning of the imaging unit carrier 118. The drive unit 300 is controlled by the controller 106. Reference will be made below. Figure 3 The method for positioning the imaging unit carrier 118, performed by the controller 106, is described.
[0034] The microscope column 116 may further include a linear encoder 208 for determining the vertical position of the imaging unit support 118. In this embodiment, the linear encoder 208 exemplarily includes a scale arranged parallel to the main shaft 200 and a sensor arranged on the imaging unit support 118 and configured to read the scale. The sensor is further configured to generate a sensor signal corresponding to the reading, and thus corresponding to the vertical position of the imaging unit support 118, and configured to transmit the sensor signal to the controller 106. Alternatively, the sensor signal corresponding to the vertical position of the imaging unit support 118 may be generated in other ways, such as by laser distance measurement.
[0035] Figure 3 It is based on Figure 1 Block diagram of microscope system 100.
[0036] The controller 106 is configured to control the functional units of the microscope system 100. In this embodiment, the controller 106 is configured to control the imaging unit 104, for example, to capture microscopic images, and to control the microscope stage 112, for example, to position the object 108 within the field of view of the imaging unit 104. The controller 106 is further configured to control the drive unit 300, including the coarse drive device 302 and the fine drive device 304, based on user input received through the user input device 306, in order to position the imaging unit carrier 118. Specifically, the controller 106 is a closed-loop controller configured to control the drive unit 300 based on sensor signals received by the controller 106.
[0037] In an exemplary method for positioning the imaging unit carrier 118, the controller 106 receives user input via the user input device 306, corresponding to a set value for the position of the imaging unit carrier 118 along the vertical direction V. Then, the controller 106 controls the coarse drive device 302 to move the imaging unit carrier 118 along the vertical direction V to a position within one step of the set position. Thus, the position of the imaging unit carrier 118 is coarsely adjusted. Then, the controller 106 controls the fine drive device 304 to move the imaging unit carrier 118 along the vertical direction V to a position within one step of the set position. Since the step size of the fine drive device 304 is much smaller than the step size of the coarse drive device 302, precise positioning of the imaging unit carrier 118 along the vertical direction is achieved.
[0038] In all the accompanying drawings, elements that have the same or similar function are denoted by the same reference numerals. As used herein, the term "and / or" includes any and all combinations of one or more of the related listed items and may be abbreviated as " / ".
[0039] Although some aspects are described in the context of the apparatus, these aspects clearly also represent a description of the corresponding method, where a module or apparatus corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method step also represent a description of a corresponding module, item, or feature of the corresponding device.
[0040] List of reference numerals
[0041] 100 Microscope Systems
[0042] 102 Microscope stand
[0043] 104 imaging units
[0044] 106 Controller
[0045] 108 objects
[0046] 110 base
[0047] 112 Microscope stage
[0048] 114 Observation Position
[0049] 116 Microscope column
[0050] 118 Imaging Unit Carrier
[0051] 200 spindle
[0052] 202 Spindle Bearing
[0053] 204 Rotary Electric Machine
[0054] 206 piezoelectric motor
[0055] 208 Linear Encoder
[0056] 300 drive units
[0057] 302 Coarse Drive Unit
[0058] 304 precision drive unit
[0059] 306 User Input Devices
[0060] O optical axis
[0061] V (vertical direction)
Claims
1. Microscope stand (102), including: The base (110) includes an observation position (114) configured to receive an object (108). The microscope column (116) extends vertically (V) from the base (110); and An imaging unit carrier (118) is movably mounted to a microscope column (116) and configured to mount an imaging unit (104) to a microscope support (102). The imaging unit (104) is configured to generate a microscopic image of an object (108) received at the observation position (114). The microscope column (116) includes a coarse drive device (302), which is configured to coarsely adjust the vertical position of the imaging unit support (118) along the vertical direction (V); and A fine drive device (304) is mechanically connected to and arranged in series with a coarse drive device (302). The fine drive device (304) is configured to finely adjust the vertical position of the imaging unit carrier (118) along the vertical direction (V). The coarse drive device (302) is arranged and configured to be movable by the fine drive device (304), and the fine drive device (304) is configured to move the coarse drive device (302) and the imaging unit carrier (118) in the vertical direction (V) in order to fine adjust the vertical position of the imaging unit carrier (118).
2. The microscope stand (102) according to any one of the preceding claims includes a controller (106) configured to control the coarse drive device (302) and the fine drive device (304) based on a user input of a set value corresponding to the vertical position of the imaging unit carrier (118) in the vertical direction (V).
3. The microscope support (102) according to claim 2 includes a linear encoder (208) configured to generate a sensor signal corresponding to the vertical position of the imaging unit carrier (118) in the vertical direction (V) and transmit the sensor signal to the controller (106).
4. The microscope stand (102) according to claim 3, wherein, The controller (106) is a closed-loop controller (106) configured to control the coarse drive device (302) and the fine drive device (304) based on sensor signals.
5. The microscope stand (102) according to any one of the preceding claims, wherein, The stroke of the fine drive device (304) is less than that of the coarse drive device (302).
6. The microscope stand (102) according to any one of the preceding claims, wherein, The stroke of the coarse drive (302) is at least 5 mm and / or at most 2000 mm.
7. The microscope stand (102) according to any one of the preceding claims, wherein, The travel of the precision drive (304) is at least 1 micrometer and / or at most 500 micrometers.
8. The microscope stand (102) according to any one of the preceding claims, wherein, The step size of the fine drive device (304) is smaller than that of the coarse drive device (302).
9. The microscope stand (102) according to any one of the preceding claims, wherein, The step size of the precision drive device (304) is at least 1 nanometer and / or at most 1000 nanometers.
10. The microscope stand (102) according to any one of the preceding claims, wherein, The coarse drive device (302) is a spindle drive device, or a rack and pinion drive device, or a belt drive device.
11. The microscope stand (102) according to any one of the preceding claims, wherein, The coarse drive device (302) includes a stepper motor, a DC motor, a brushless DC motor, or a linear motor.
12. The microscope stand (102) according to any one of the preceding claims, wherein, The precision drive device (304) includes a piezoelectric motor (206) or a stepper motor.
13. The microscope stand (102) according to any one of the preceding claims, wherein, The base (110) includes a microscope stage (112) configured to be movable in at least one direction perpendicular to the vertical direction (V); and wherein the top surface of the microscope stage (112) includes an observation position (114).