Scanning device

Abstract

A scanning device is provided for scanning a target area of ​​a sample. [Solution] A scanning device comprising: a transport system configured to support a sample and move a target region of the sample between a first location and a second location; a casing configured to support the transport system and mechanically coupled to the transport system such that the movement of the transport system induces vibrational motion in the casing; and a controller configured to accelerate the transport system in a first direction from the first location to the second location, causing a reaction force in a second direction and an initial vibrational motion of the casing in a second direction, decelerating the transport system in a first direction to bring the transport system to a stop when the sample is at the second location, and generating a reaction force in the first direction relative to the casing to balance the vibrational motion of the casing in a second direction to bring the casing to a stop.

Description

Technical Field

[0001] Field of the Invention The present invention generally relates to a scanning device for scanning and imaging materials in the form of slide specimens, such as biological materials, such as human tissue specimens.

Background Art

[0002] Background Currently, mechanical and optical technologies are used to create digital scanners for medical imaging and digital printing engines. Typically, an imaging device comprising a scanning and imaging system captures a plurality of smaller images of several target areas, known as swaths or swath scans or tiles, and creates a large image of the slide specimen by stitching these plurality of smaller images together. When capturing a plurality of swaths, the scanning stage holding the specimen moves to a new imaging position between each swath or tile so that a new target area of the slide specimen can be imaged. However, the scanning stage must be stationary after being moved and before each image is captured in order to reduce imaging artifacts caused by imaging the moving target area.

[0003] These scanning systems are preferably isolated as much as possible from external vibrations, such as those caused by external environmental factors. Generally, this isolation is implemented in the form of elastic vibration isolation (AV) mounts, which can be placed between the scanning system and the rest of the scanning device, and optionally between the scanning device and the surface on which the scanning device is placed, such as a workbench. Typically, the stage of the scanning system is mounted on a scanner structure that may include an imaging system for the scanning system, and the scanner structure itself may be mounted on a mount such as an AV mount. Therefore, when the scanning stage moves from one imaging position to another, the acceleration and deceleration of the moving scanning stage cause vibrations in the scanner structure on the mount. These vibrations cause imaging artifacts unless there is enough time left for the vibrations to sufficiently attenuate before the image is acquired.

[0004] To reduce imaging artifacts, scanning systems are known to check, for example, through motion sensors or cameras and controllers, that the position of the scanning stage remains within a specified range of the target imaging position for a specified time before the image of the target area is acquired. While this reduces the possibility of imaging artifacts, this method slows down the overall image acquisition speed due to the additional waiting time between consecutive image acquisitions.

[0005] Another known solution is to use post-processing techniques to attempt to eliminate some of the effects caused by vibration. However, there are limits to the magnitude of the rate of change and positional errors that this technique can compensate for. [Overview of the Initiative]

[0006] Summary of the Invention According to a first embodiment, a scanning device is provided for scanning a target region of a sample. The scanning device comprises a transport system configured to support the sample and move the target region between a first location and a second location, and a casing configured to support the transport system. The casing is mechanically coupled to the transport system such that the movement of the transport system induces vibrational motion in the casing. The scanning device also comprises a controller configured to i) accelerate the transport system in a first direction from the first location to the second location, causing a reaction force in the second direction and an initial vibrational motion of the casing in the second direction, and ii) decelerate the transport system in the first direction to bring the transport system to rest when the sample is at the second location, and generate a reaction force in the first direction relative to the casing to balance the vibrational motion of the casing in the second direction to bring the casing to rest.

[0007] The present invention aims to provide an improved scanning device for use with any device that displaces a target region of a sample from a first position to a second position, and as a result, when the target region reaches the second position, the target region has a shorter position stabilization time. Such a scanning device can be conveniently used in imaging devices for scanning and imaging materials such as biomaterials, for example, in the form of slide specimens such as human tissue specimens, but not limited to these.

[0008] The movement of the transport system induces elastic strain in the casing, which displaces at least partially in the opposite direction to the movement of the transport system, as vibrations of the casing are induced.

[0009] Advantageously, the scanning device is positioned such that vibrations induced in the casing during the acceleration of the transport system are canceled out during the deceleration of the transport system. As the transport system accelerates, its movement accelerates the casing in the opposite direction. Since the casing is in a fixed position, the acceleration of the transport system and the reaction acceleration of the casing cause elastic deformation of the casing, e.g., the elastic parts of the casing and / or elastic parts provided on the casing, which thus stores a certain amount of resulting elastic potential energy. In particular, the elastic parts begin to vibrate back and forth from their resting position, i.e., the position occupied by the absence of any acceleration or deceleration and / or vibration. By appropriately timing the deceleration of the transport system to occur when the casing is moving in the opposite direction to the transport system and toward its resting position, the momentum of the transport system and the casing cancel each other out, and the entire scanning device comes to a standstill when the transport system has substantially reached a second position. This reduces the time required for the target region to reach positional stability and therefore reduces the time required to acquire an image of the target region without artifacts being introduced into the image as a result of induced vibrations of the entire system.

[0010] The scanning device preferably further comprises at least one mount configured to support the casing on its outer surface. In some examples, at least one mount is attached to the casing and configured to support the casing. Preferably, the scanning device comprises a plurality of mounts, e.g., two or more mounts. The casing may be provided with at least one mount configured on its outer surface on which the scanning device rests.

[0011] Preferably, at least one mount includes an elastically deformable material. At least one mount may be the elastic portion described above. It will be understood that while the transport system moves, the contact surfaces and outer surfaces of the mount do not change or move, but the portion of the mount(s) between the contact surface and the casing vibrates and elastically deforms from one side to the other around its stationary position.

[0012] One or more mounts may be positioned and configured to isolate the scanning device from the surrounding environment in order to help ensure that vibrations present in the external environment that could affect the scanning process do not enter the scanning device.

[0013] In some examples, the movement of the casing is configured to induce vibration in at least one mount, and this vibration causes subsequent oscillating motion of the casing. Generally, once the casing is initially displaced in the opposite direction to the transport system, the movement of the transport system causes at least one mount to elastically deform. The elastic potential energy stored in the mount acts to accelerate the casing in the same direction as the transport system moves until the casing reaches its maximum displacement, and the casing begins to oscillate back and forth on the mount.

[0014] This vibrational motion can be measured using any suitable technique for determining the vibrational motion of an object, and a vibration profile can be determined. This can form part of the calibration process. The vibration profile can be advantageously used to ensure that the timing of deceleration is chosen such that the momentum of the transport system and the momentum of the part of the scanning device vibrating on the mount, including the casing, are substantially the same magnitude but are directed in opposite directions so as to substantially cancel each other out, allowing the transport system, and thus the entire scanning device, to be substantially stationary when the target region reaches a second position. Thus, a biological sample located on the target region can be imaged without artifacts being introduced into the image as a result of induced vibrations within the scanning device, and the time required for the target region to reach positional stability is significantly reduced.

[0015] At least one mount may have a low damping coefficient. This helps ensure that at least one mount itself does not over-dampe the scanning device, and as a result, timed deceleration can be used instead of relying on the damping provided by the mount to counteract the vibrations. This results in more accurate, consistent, and effective damping during repeated acceleration and deceleration events, such as between consecutive experiments or between consecutive image samples. In this regard, momentum cancellation can be considered effective damping from an image perspective, as the vibrational motion is effectively eliminated by being canceled out.

[0016] Preferably, at least one mount includes a first damping coefficient in a first direction and a second damping coefficient in another (second) direction. The first damping coefficient may be different from the second damping coefficient. For example, the first damping coefficient may be greater than or less than the second damping coefficient. The first direction may be perpendicular to the other (second) direction. In this way, the mount provides different levels of damping in different directions. For example, the mount may provide a high level of damping in one direction and a low level of damping in the other direction. This allows the scanning device to acquire different effective sensitivities to motion in different directions. As a result of the different damping coefficients, vibrations or oscillations induced in one direction within the system may be more effectively canceled out by the mount in the first direction compared to the second direction, or vice versa.

[0017] In some exemplary devices, the first direction may be parallel to the direction of motion of the target region from the first location to the second location, and the second direction may be perpendicular to the direction of motion of the target region. In this case, preferably, the first damping coefficient is smaller than the second damping coefficient. This has the effect that the mount provides a greater cancellation effect in the second direction perpendicular to the direction of motion of the target region, and therefore the mount provides a larger damping for vibrational motion in this direction. Similarly, the mount provides a smaller cancellation effect in the first direction parallel to the direction of motion of the target region, and therefore the mount provides a smaller damping for vibrational motion in this direction. As described above, this ensures that the effective damping in the direction parallel to the direction of motion of the target region is provided by timed deceleration rather than by the mount, which helps ensure consistent effective damping.

[0018] At least one mount is preferably included in the scanning device and preferably attached to the casing, but the presence of at least one mount is not essential, and it will be understood that the same momentum cancellation effect can be achieved by considering the casing as a feature where elastic potential energy is stored, vibrations are induced and subsequently canceled out.

[0019] The casing may also have a low damping coefficient. The casing may have one or more of the damping features described above with reference to at least one mount. The advantages associated with a casing having a low damping coefficient are substantially the same as those described above with reference to at least one mount.

[0020] The scanning device may further comprise a computing system preferably communicatively coupled to a controller, the computing system preferably configured to instruct the controller to accelerate and decelerate the transport system. In some examples, the controller may comprise a drive system, and thus the computing system may be considered to communicate with the drive system, for example, through the controller. The drive system may be configured to cause movement of the transport system, such as acceleration and deceleration, via signals or commands received from the controller and / or the computing system.

[0021] The computing system may be configured to detect and monitor the vibrational motion of the casing. The computing system may be configured to determine the vibration profile of the casing. The vibration profile may also be called the motion profile, and the vibration profile substantially corresponds to the vibrational motion of the casing. The computing system may be configured to store the vibration profile of the casing in the computing system's memory. The computing system may be configured to calculate the time for the controller to decelerate the transport system, such that the calculated time is such that the deceleration occurs substantially simultaneously with the casing moving in the direction opposite to the direction of deceleration. Thus, the computing system may be configured to calculate the time for the controller to decelerate the transport system based at least in part on the stored vibration profile of the casing. In this way, a relationship can be established between the motion of the transport system and the vibrational motion of the casing.

[0022] The computing system is preferably configured to instruct the controller to accelerate the transport system and decelerate the transport system within one complete vibration cycle. Preferably, the computing system is configured to instruct the controller to accelerate the transport system and decelerate the transport system within a first vibration cycle. In this way, the momentum of the casing will closely match the momentum of the transport system and the target area after one complete vibration cycle, since the vibration has not yet been significantly damped and therefore the cancellation is most effective at this point.

[0023] In another embodiment, an imaging apparatus is provided that includes a scanning device according to any of the examples described above.

[0024] In another embodiment, a method for operating a scanning device, comprising the step of accelerating a transport system in a first direction to move a sample from a first location to a second location, wherein accelerating the transport system induces vibrational motion in a casing mechanically coupled to the transport system, the casing being configured to support the scanning system for scanning the sample. A method is provided which includes accelerating, the acceleration causing a reaction force in a second direction and an initial vibrational motion of the casing in a second direction; and decelerating, the deceleration of a transport system in a first direction to bring the transport system to rest when the sample is in a second location, wherein the deceleration causes a reaction force in the first direction relative to the casing to balance the vibrational motion of the casing in a second direction to bring the casing to rest.

[0025] In some examples, the motion of the casing involves multiple vibration cycles, and deceleration is timed to occur during the first vibration cycle of the casing. In some other examples, deceleration is timed to occur during vibration cycles that follow the first vibration cycle of the casing.

[0026] Preferably, the casing vibrates at its resonant frequency.

[0027] According to another aspect, there is provided a method for generating a movement profile for a scanning device, the method comprising: imparting an impulse to a transport system to move the transport system from a first location to a second location towards a target region, the movement of the transport system causing movement of a casing of a scanning system; measuring a resonant frequency of the casing; calculating at least one of an acceleration and / or a deceleration of the casing based on the resonant frequency; and generating a movement profile of the casing based on the calculated acceleration and / or deceleration.

[0028] Here, as an example, the present invention will be described with reference to the accompanying drawings.

Brief Description of the Drawings

[0029] [Figure 1] A diagram showing a schematic scanning device. [Figure 2] A diagram showing a part of a schematic scanning device. [Figure 3] A diagram showing a schematic scanning device during a part of a scanning process. [Figure 4] A diagram showing a schematic scanning device during a part of a scanning process. [Figure 5] A diagram showing a schematic scanning device during a part of a scanning process. [Figure 6] ] [[ID=]

[31] ]A diagram showing a schematic scanning device during a part of a scanning process. [Figure 7] A graph showing a change in displacement over time. [Figure 8] A graph showing a change in velocity over time. [Figure 9] A graph showing a change in acceleration over time. [[ID=]

[41] ] [Figure 10] A diagram showing an exemplary movement profile. [Modes for carrying out the invention]

[0030] Detailed explanation Figure 1 shows an exemplary scanning device 1 for imaging a sample such as a biological sample. The scanning device 1 generally comprises a scanning system 2 for scanning the sample. The scanning device 1 comprises an imaging system 3 which includes an imaging acquisition device (e.g., a camera) for collecting images of the sample and an illumination system for illuminating the sample with light. The scanning device 1 further comprises a transport system 4 for moving the sample relative to the imaging system 3. The transport system 4 is supported by a casing 20. In some examples, such as those shown in Figure 1, at least one mount 6 is positioned and configured to support the scanning device 1 on an external surface 8, such as a table, workbench, or floor.

[0031] The sample to be scanned is placed on a target area 10 of a rigid substrate 12 to form a slide specimen. The substrate 12 is formed from a material suitable for the experiment under consideration. The substrate 12 may be sized to accommodate one or more samples within the target area 10. The target area 10, sometimes called the sample area, is, for example, the area scanned by the scanning system 2. The substrate 12 may be a separate object in the form of a microscope slide based on a borosilicate glass slide, for example, because it is readily available and suitable for most common applications. However, as should be understood, the composition of the substrate 12 may be selected to suit individual experiments; for example, the substrate may be glass or plastic. The substrate 12 may be flat or recessed with microwells and structures.

[0032] As described above, the transport system 4 moves the target region 10 and, therefore, moves the sample relative to the imaging system 3 in order to image the target region 10.

[0033] The transport system 4 includes a support mechanism 14 on which the substrate 12 is placed. Thus, the support mechanism 14 supports the substrate 12. The transport system 4 also includes a drive system 16 for moving the support mechanism 14 relative to the imaging system 3. The drive system 16 moves the support mechanism 14 left and right in the y-direction and reciprocates (i.e., forward and backward) in the x-direction. This allows the support mechanism 14 to be positioned at different locations relative to the imaging system 3, which has the effect of positioning the substrate 12 and the target region 10 at different locations relative to the imaging system 3. It will be understood that the x-direction and y-direction are perpendicular directions in the horizontal plane. A controller is coupled to the transport system 4 via the drive system 16, and as a result, the controller controls the movement of the transport system 4 via the drive system 16. The controller accelerates the transport system 4 to move the target region 10 outward from a first location toward a second location, and decelerates the transport system 4 as the target region 10 approaches the second location.

[0034] The scanning system 2 is supported by a casing 20. In some examples, the scanning system 2 is located inside the casing 20 and therefore supported within the casing 20. In other examples, the scanning system 2 is outside the casing, and the casing 20 provides external support to the scanning system 2.

[0035] For example, in some of the examples shown in Figure 1, at least one mount 6 may be attached directly or indirectly to the casing 20. The casing 20 may also house other components such as computing components, electronics, and power supply components for at least partially controlling and powering the scanning system 2. The computer control system may be connected to some or all of the individual components of the scanning device 1, including the scanning system 2, the transport system 4, the drive system 16, and all the subordinate components of these systems. Thus, all the individual components and subordinate components of the scanning device 1 are computer-controlled, providing a fully automated computer control system. A computer program runs on the computer control system, which can be programmed by a user. The user can input the necessary parameters and details of the imaging sequence into the computer program, and as a result, once the program is executed, the scanning device 1 executes the required imaging sequence without any further interaction from the user until the imaging sequence is completed.

[0036] As shown in Figure 2, the support mechanism 14 is in the form of a stage 15. Thus, the substrate 12 is positioned on the stage 15 and supported by the stage 15. The stage 15 is coupled to a drive system 16 that moves the stage 15. The drive system 16 moves the stage 15 laterally, but its movement is limited to a single horizontal plane. Thus, the stage 15 can move left and right and forward and backward. Thus, the drive system 16 is a multi-directional drive system, for example, an X+Y drive system. The drive system 16 ensures that the target area 10 is precisely positioned relative to the imaging system 3, and the drive system 16 allows for fine adjustment of the position in the x and y directions as needed. As can be understood, in some examples, the drive system 16 can be a unidirectional drive system, for example, the drive system 16 may move the stage 15 in either the x or y direction.

[0037] The scanning system 2 may include a scanner 18 that scans a target area 10 on the substrate 12. In the illustrated example, the scanner 18 may be in the form of a digital scanner 18.

[0038] The digital scanner 18 may be configured to perform a swath scan across the entire target area 10 of the substrate 12, as shown in part S of Figure 1. The target area 10 may be thought to be divided into several adjacent subsections 11. The swath scan involves sequentially scanning one or more subsections 11 of the target area 10 when the target area 10 is larger than the field of view (FOV) 5 of the digital scanner 18. The percentage of the total surface area of ​​the substrate 12 that can be seen by the digital scanner 18 at one time is determined by the FOV 5 of the digital scanner 18. Thus, the FOV of the digital scanner 18 determines what percentage of the surface area of ​​the target area 10 can be scanned at one time.

[0039] Generally, since the target area 10 on which the sample is placed is larger than the FOV 5 of the digital scanner 18, the digital scanner 18 can only see a limited proportion of the sample within the target area 10 at a time. In order to scan the entire sample on the target area 10, the sample needs to be moved relative to the FOV 5 of the digital scanner 18.

[0040] The digital scanner 18 detects what percentage of the sample the target region 10 covers so that the entire target region 10 is captured when the swath scan is performed. Thus, the digital scanner 18 can ensure that all of the sample corresponding to the target region 10 is scanned. As understood, different swath scans can be combined using an algorithm that identifies the edges of different swath scans and matches the edges of consecutive swath scans to generate a final larger scan of the entire scanning sequence experiment being performed.

[0041] Swath scanning is performed in one direction within the horizontal plane, for example, approximately 10 mms. -1This is a continuous movement at a speed of . For example, with respect to the initial y-coordinate, the swath scan is performed in the x-direction to scan the sample for all x-coordinates. Once the swath scan is completed at the initial y-coordinate, the target region 10 needs to be moved in the y-direction before the next swath scan in the x-direction is completed, in order to ensure that the entire sample region 10 is scanned. The movement of the transport system 4, and by extension the target region 10, in the y-direction is an example of the movement of the transport system 4 from the first location to the second location described above. This is represented by the y-direction (or -y-direction) arrow in Figure 2, whereas the movement in the x-direction described in relation to the swath scan is represented by the x-direction (or -x-direction) arrow in Figure 2.

[0042] Ideally, during each change in position between swa scans, all parts of the instrument would be stabilized, and therefore there would be no visualization problems; that is, the captured scan would be free from blurring as a result of movement of the support mechanism 14. However, in practice, this is a rare case, and the resulting scan would contain artifacts as a result of movement of at least some components of the scanning device 1. This problem is described in more detail below.

[0043] The transport system 4 can be thought to be configured to move the target area 10 between a first location where the scanning system 2 scans a first imaging area and a second location where the scanning system 2 scans a second imaging area. Here, the first imaging area and the second imaging area may each correspond to an area scanned by a swath scan.

[0044] As can be seen more clearly in Figure 2, the stage 15 comprises a plurality of plates, including a first plate 22 and a second plate 24. The first plate 22 and the second plate 24 are vertically aligned with each other so that they are positioned vertically. Both the first plate 22 and the second plate 24 are connected to the drive system 16. The first plate 22 holds the substrate 12 and is configured to move the substrate 12 and the target region 10 in the x-direction during a swath scan. The second plate 24 is configured to move the first plate 22, and therefore the substrate 12 and the target region 10, from a first location to a second location in the y-direction. In other words, the first plate 22 moves during a swath scan, and the second plate 24 moves between swath scans. The first plate 22 is generally lighter in mass than the second plate 24, ensuring that the first plate 22 can move quickly during scanning.

[0045] The casing 20 is mechanically coupled to the transport system 4 such that the movement of the transport system 4 induces vibrational motion in the casing 20. In particular, as a result of the additional mass of the second plate 24, when the stage 15 moves from a first location to a second location between swath scans, the movement is induced in the casing 20 in the opposite direction, and therefore the movement of the transport system 4 causes the movement of the casing 20. Since the scanning system 2 is supported by the casing 20, the movement of the transport system 4 causes the movement of the scanning system 2. In particular, when the stage 15 moves from a first location to a second location, elastic strain occurs in the casing 20, and as a result, at least a portion of the casing 20 is displaced in the opposite direction, and therefore the movement of the stage 15 causes the movement of the casing 20 and the scanning system 2.

[0046] More specifically, when the drive system 16 accelerates the second plate 24, causing the stage 15 to initially accelerate from the first location to the second location (i.e., acceleration in the first direction), a reaction force in the opposite direction (i.e., the second direction) is applied to the scanner 18, causing the scanner 18 to displace in the second direction, as shown in Figure 3. In the illustrated example, one or more mounts 6 to which the scanning system 2 is attached are made of an elastically deformable material, and therefore the movement of the scanning system 2 results in elastic deformation of the mounts 6. The elastic potential energy stored in the mounts 6 is released, causing acceleration of the scanning system 2 in the same direction as the motion of the stage 15 (i.e., the first direction), as shown in Figure 4. If no other forces act on the scanning device 1, the scanning system 2 will continue to oscillate back and forth on the mounts 6, as shown in Figure 5, before gradually coming to a stop. The oscillation of the scanning system 2 is perpendicular to the direction of the swath scan. Therefore, the vibration scanning system 2 will introduce imaging artifacts if the next swath scan is initiated before the vibrations have sufficiently decayed to a level that does not adversely affect image acquisition. These vibrations need to be compensated to ensure that imaging artifacts are not introduced. As described above, elastic strain is explained with reference to the mount 6, but it will be understood that the casing 20 also undergoes elastic strain due to the movement of the stage 15. As will be understood, in a scanning device without a mount, only the movement of the stage 15 results in elastic strain in the casing 20.

[0047] It was found that by timing the deceleration of stage 15 to occur substantially simultaneously with scanning system 2 moving in the opposite direction to stage 15 toward its resting position, where it has completed 3 / 4 of the first or subsequent vibration cycle, as stage 15 reaches the second location, the momentum of stage 15 and the momentum of scanning system 2 substantially cancel each other out, as shown in Figure 6, so that scanning device 1 comes to a rest, allowing subsequent scan acquisition to be performed with a stable system. When the sample is at the second location, transport system 4 is decelerated in the first direction (or accelerated in the second direction, which corresponds to negative acceleration, i.e., deceleration in the first direction), so that transport system 4 comes to a rest. The deceleration imparts a reaction force to casing 20 in the first direction (i.e., in the opposite direction to the force applied to transport system 4 to decelerate transport system 4), and this reaction force equilibrates the vibrational motion of casing 20 in the second direction, and thus brings casing 20 to a rest. The vibration of scanning system 2 is effectively minimized by timing the deceleration of stage 15 to occur when the displacement of scanning system 2 is the same magnitude and in the opposite direction as during the acceleration of stage 15.

[0048] The controller connected to the drive system 16 is configured to accelerate the transport system 4, particularly the second plate 24 of stage 15, so that when the target area 10 is approaching the second location, it moves the target area 10 outward toward the second location until the target area 10 comes to rest at the second location, thereby decelerating the transport system 4, particularly the second plate 24 of stage 15. The drive system 16 decelerates the transport system 4, particularly the second plate 24 of stage 15, substantially simultaneously with the scanning system 2 moving in the opposite direction to the deceleration direction. This means that the controller is configured to time the deceleration of the transport system 4 as described above. The timing of the deceleration is such that when the second plate 24 of stage 15 reaches the second location and attempts to stop moving, the scanning system 2, moving in the opposite direction, reaches its maximum displacement, and as a result, the combined momentum of the moving second plate 24 and the scanning system 2 moving in the opposite direction cancels out, causing both the second plate 24 and the scanning system 2 to come to a stop. In practice, the second plate 24 of stage 15 is timed to move according to the vibration frequency of the scanning system 2. This means that the forces applied to the casing 20 by the transport system 4 cancel out the forces present in the transport system 4 as a result of acceleration and deceleration. The initial acceleration of the transport system 4 imparts an initial force to the casing 20, initiating the vibration motion. This initial force is in the opposite direction to the acceleration, causing the casing to initially displace in the opposite direction to the acceleration. The deceleration of the transport system 4 imparts a subsequent force to the casing 20 to minimize, and preferably substantially cancel out, the vibration motion. This subsequent force is in the opposite direction to the initial force and therefore acts to counteract the forces within the vibrating casing 20 moving in the second direction, thus stopping the movement of the casing 20 when the transport system 4 stops moving at the second location.

[0049] Preferably, the casing 20 and / or mount 6 have a relatively low damping coefficient, e.g., a damping ratio of less than 0.1, such that vibrations are substantially corrected by relying on the cancellation of momentum present within the scanning device 1 rather than through damping by the mount 6. In this way, the mount 6 functions to isolate the scanning device 1 from external vibrations, such as vibrations present in the external environment, rather than from vibrations occurring and present within the scanning device 1. A mount 6 with a higher damping coefficient can more effectively isolate the scanning device 1 from external vibrations.

[0050] In some exemplary scanning devices 1, the mount 6 may have different attenuation coefficients in the x and y directions. For example, the attenuation coefficient in the direction perpendicular to the swath scan direction (y direction) may be smaller than the attenuation coefficient in the direction parallel to the swath scan direction (x direction). In other words, the attenuation coefficient in the direction parallel to the direction of movement from the first location to the second location may be smaller than the attenuation coefficient in the direction perpendicular to the direction of movement from the first location to the second location. Of course, in some exemplary scanning devices 1, the mount 6 may have the same attenuation coefficient in both the x and y directions.

[0051] The movement profile of the scanning device 1, which describes how the scanning device 1 moves as a result of the elastic deformation of the mount 6 and subsequent vibration of the scanning system 2, may first be calibrated to determine the vibration profile, which may then be used to determine the timing of the deceleration of the given scanning device 1. As will be understood, the optimal timing will differ among different instances of the scanning device 1 (e.g., due to defects or inconsistencies during the manufacturing process), the installation location, and the specific damping characteristics of the mount 6.

[0052] Preferably, the mount 6 is selected to have a damping coefficient such that, as a result of the rigidity of the mount 6 and the mass of the scanning system 2, the mount 6 gives the entire system a resonant frequency close to the frequency of motion between successive swaths. In other words, the resonant frequency is similar to the frequency of movement of the transport system 4 from the first location to the second location.

[0053] Due to the low damping coefficient of the mount 6, the vibrations do not significantly dampen after one cycle, so the momentum of the scanning system 2 closely matches the momentum of the transport system 4 at the end of one complete cycle of vibration on the mount 6. Given this, it is preferable to first accelerate and then decelerate the transport system 4 within the first vibration cycle of the mount 6 in order to minimize the amount of energy lost due to vibration damping and to ensure that the momentum of the scanning system 2 substantially matches the momentum of the transport system 4. In other words, both acceleration to move the target region 10 outward from the first location toward the second location and deceleration to bring the target region 10 to rest when it is in the second location occur within the same vibration cycle.

[0054] While the explanation regarding damping refers to the mount, it should be understood that this explanation applies equally to the casing. Therefore, in the absence of the mount, it is the casing that has a low damping coefficient to ensure that the momentum of the scanning system closely matches the momentum of the stage.

[0055] As can be understood, deceleration can occur during any oscillation cycle following the first oscillation cycle. However, some energy will be lost during each subsequent cycle, for example due to friction, and therefore the momentum offsetting between the scanning system 2 and the transport unit 4 becomes less effective as the oscillation cycle in which deceleration occurs becomes slower.

[0056] It should be noted that increasing the rigidity of mount 6 or reducing the mass of scanning system 2 will increase the resonant frequency of mount 6, allowing for faster movement between adjacent swath scans.

[0057] Figures 7–9 show some exemplary plots of the changes in displacement, velocity, and acceleration between each motion stage. These simplified plots generally illustrate Stage 15, which moves with constant acceleration within a given motion stage and changes substantially instantaneously from one motion stage to the next. However, in reality, the acceleration of the scanning system 2 changes continuously as the mount 6 deforms, providing a restoring force that brings the entire system back to equilibrium when stationary.

[0058] Referring first to Figure 7, this graph shows how the displacements of stage 15 and scanning system 2 change over time. Stage 15 moves from the first location to the second location at a substantially constant speed throughout. The acceleration and deceleration phases at the first and second locations can be seen on the graph. Scanning system 2 is shown moving from its initial position to its maximum displacement in the opposite direction to that of stage 15, oscillating to its maximum displacement in the same direction as the moving stage 15, and then returning to its initial starting position. Scanning system 2 reaches its maximum negative displacement at approximately half the time it takes for stage 15 to move from the first location to the second location.

[0059] Preferably, the scanning system 2 completes three-quarters of the oscillation cycle before the deceleration applied to the stage 15 generates forces and momentum that balance the forces and momentum acting on the scanning system 2 so that it comes to rest at its initial position. If no deceleration is applied to the stage 15, no further force is applied to the scanning system, and the scanning system 2 moves further from its initial position toward a second location of the stage 15, returns to its initial position, and thus completes the oscillation cycle and starts a new oscillation cycle until the oscillation gradually weakens while the potential energy is dissipated.

[0060] Looking at Figure 8, we see the rate of change (i.e., acceleration) of both the stage 15 and the scanning system 2. From this figure, it is clear that the stage 15 first accelerates (outward from the first position), then moves at a substantially constant velocity (between the first and second locations), and then decelerates (while approaching the second location). During the acceleration phase of the stage 15 in the first direction, the scanning system 2 moves in a second direction opposite to the stage 15 as a result of the reaction force exerted by the stage 15 within the scanning system 2. The applied force acts to accelerate the scanning system 2 from a stationary state in the second direction opposite to the acceleration direction of the stage 15. During the constant velocity phase of the stage 15, no further force is exerted on the scanning system 2 by the stage 15. Therefore, during this phase, the elastic energy from the initial force accumulated (in either the casing or mount, if present) is released as a force that accelerates the scanning system 2 back to the first direction (thus the scanning system 2 is now moving in the opposite direction to its initial direction of travel). To decelerate stage 15, it is necessary to apply an effective force to stage 15 to slow it down, and this force must be applied in the opposite direction to the direction of stage 15's movement. This force can be thought of as applying acceleration to stage 15 in a second direction. This imparts a corresponding opposite force to the scanning system 2, and this corresponding opposite force is applied in the first direction. At this point, since the scanning system 2 is moving in the second direction, the corresponding opposite force acts against the movement of the scanning system 2, stopping it. Therefore, by the time stage 15 reaches the second location and comes to a stop, the vibrations of the scanning system 2 are canceled out, and as a result, the scanning system is also at a stop. Both the scanning system 2 and stage 15 are at a stop.

[0061] Finally, referring to Figure 9, the rate of change of acceleration for stage 15 and scanning system 2 is shown. As can be seen, stage 15 initially accelerates, followed by a period of constant velocity, i.e., no acceleration, and then decelerates. It can also be seen that scanning system 2 oscillates between acceleration and deceleration. In particular, during the first stage, as shown in Figure 9, both stage 15 and scanning system 2 begin to accelerate substantially simultaneously, but in opposite directions. Similarly, during the final stage, both stage 15 and scanning system 2 begin to decelerate substantially simultaneously, but in opposite directions.

[0062] In summary, the resonant frequency of mount 6 is measured, and the movement profile of stage 15 is timed so that a specific stage of movement between the first and second locations coincides with a particularly favorable point within the vibration cycle. The entire system allows for a reduction in overall scan time because the time between adjacent swath scans is shortened.

[0063] It will be understood that the timing and rate of deceleration depend at least on the effective mass, acceleration rate, and elastic properties of the casing 20 and the scanning system 2, as well as any other components provided thereon that vibrate together with the casing 20 and the scanning system 2, and the elastic properties of the casing 20 and / or at least one mount 6.

[0064] The function of mount 6 is to store elastic potential energy as the mount deforms in response to the displacement of the transport system 4. However, it should be noted that mount 6 is a specific embodiment of the elastic component mechanism. In some embodiments, the casing itself may be elastically deformable or may have an elastically deformable portion that performs the same function of storing elastic potential energy. In some examples, the elastically deformable portion may be a separate part of the casing support structure 20 (e.g., an AV mount), or the elastically deformable portion may be the entire casing 20.

[0065] Preferably, the deceleration of the transport system 4 is timed during the fourth quarter of the overall vibration of the scanning system 2, i.e., when the vibrating structure (which may be a mount or more generally a casing having an elastic part) moves toward its stationary position.

[0066] The scanning device is described with reference to swa scan, but it will be understood that this is not an limitation, and any method known in the art for moving a target region from a first imaging location to a second imaging location may be used.

[0067] As described above, the motion profile describing how the scanning device 1 moves as a result of the elastic deformation of the casing 20 (and the mount 6, if present) and subsequent vibration of the scanning system 2 may first be calibrated to determine the vibration profile, which may then be used to determine the timing of the deceleration of the given scanning device 1. The purpose of the calibration is to determine the motion profile that minimizes the movement of the scanner after the stage has stopped moving.

[0068] Here, we will describe some exemplary and appropriate calibration processes.

[0069] The first method involves testing several different motion profiles, such as a predetermined motion profile or a pre-configured motion profile, to determine the optimal motion profile for a given device, a given setup, and a given external environment (e.g., the surface on which the device is located).

[0070] To initiate the calibration process, the stage is moved using a predetermined motion profile consisting of acceleration, constant velocity, and deceleration phases. This predetermined motion profile may be predetermined, stored on a computing device, or based on a computer model. The stage is moved a different number of times, and each time the stage moves, the constant velocity at which the stage moves is gradually increased, and the magnitude of the scanner's motion is measured after each move. The effect of the increasing constant velocity of the stage is that the acceleration and deceleration times increase, as it takes longer to accelerate the stage and bring it to a standstill. A series of data points may be collected and analyzed to determine which of the predetermined motion profiles results in the minimum motion of the scanner after the stage has stopped moving.

[0071] Figure 10 shows a series of seven exemplary motion profiles, each with an increasing constant velocity. As can be seen from Figure 10, profile 4 gives the minimum magnitude of motion after the stage stops moving. The acceleration and constant velocity from this motion profile are selected for the motion profiles in the system. If the optimal motion profile lies between test values, the optimal value can be determined by interpolation. The motion time can also be incremented by subtracting the acceleration. The error can be measured at the constant velocity stage of the motion or at the end of the motion. Minimizing the error at the constant velocity stage of the motion has the advantage that calibration becomes independent of the relative timing of the acceleration and deceleration stages. This allows for movement over various distances using the same acceleration and velocity. Minimizing the error at the stationary stage at the end of the loop has the advantage that the motion time can be shorter.

[0072] A second calibration method involves measuring the system's natural resonant frequency by supplying an impulse and calculating an optimal movement profile based on the resonant frequency. The natural resonant frequency can be measured by supplying an impulse to the system and measuring the frequency of the response. This can be done by accelerating the stage over a small portion of the resonant period of the scanner on its AV mount. The frequency of the motion after the impulse is then measured. A movement profile can then be defined, with acceleration and deceleration periods calculated from the measured natural resonant frequency.

[0073] A third calibration method includes measuring the system's natural resonant frequency by providing sweep frequency modulation to the stage position, detecting the frequency of peak disturbances, and calculating the optimal moving profile.

[0074] To determine the scanner's movement, various different sensing methods can be employed as a result of the stage's movement. For example, a stage encoder may be used to detect errors that occur because the scanner's movement results in velocity errors during constant-velocity phases of movement and position errors when the stage is stationary after the movement. Another option for detecting the scanner's movement is to use an accelerometer on the scanner. Motion sensors may also be used to detect relative motion between the scanner and the case, and relative motion between the stage and the scanner.

Claims

1. A scanning device for scanning a target area of ​​a sample, A transport system is configured to support the sample and move the target region of the sample between a first location and a second location. A casing configured to support the transport system, wherein the movement of the transport system is mechanically coupled to the transport system such that the movement of the transport system induces vibrational motion in the casing, It is a controller, The transport system is accelerated in the first direction from the first location to the second location, causing a reaction force in the second direction and an initial vibrational motion of the casing in the second direction. A controller is configured to decelerate the transport system in a first direction to stop the transport system when the sample is in the second location, and to generate a reaction force in the first direction relative to the casing to balance the oscillating motion of the casing in the second direction to stop the casing. A scanning device comprising:

2. The scanning device according to claim 1, further comprising at least one mount configured to support the casing on its outer surface.

3. The scanning device according to claim 2, wherein the at least one mount comprises an elastically deformable material.

4. The scanning device according to any one of claims 2 to 3, wherein the movement of the casing is configured to induce vibration in the at least one mount, and the vibration causes subsequent vibratory motion of the casing.

5. The scanning device according to any one of claims 2 to 4, wherein the casing has a low damping coefficient.

6. The scanning device according to any one of claims 2 to 5, wherein at least one of the mounts has a low attenuation coefficient.

7. The scanning device according to claim 6, wherein the at least one mount includes a first attenuation coefficient in a first direction and a second attenuation coefficient in a second direction, wherein the first attenuation coefficient is different from the second attenuation coefficient and the first direction is perpendicular to the second direction.

8. The scanning device according to claim 7, wherein the first direction is parallel to the direction of motion of the target region, the second direction is perpendicular to the direction of motion of the target region, and the first damping coefficient is smaller than the second damping coefficient.

9. The scanning device according to any one of claims 4 to 8, further comprising a computing system configured to detect and monitor the vibrational motion of the casing.

10. The scanning device according to claim 9, wherein the computing system is communicably coupled to the controller, and the computing system is configured to instruct the controller to accelerate and decelerate the transport system within one complete vibration cycle.

11. The scanning device according to claim 10, wherein the computing system is configured to cause the controller to accelerate and decelerate the transport system within a first vibration cycle.

12. The scanning device according to any one of claims 1 to 11, further comprising an imaging system configured to image the target region.

13. An imaging apparatus comprising the scanning device described in claim 12.

14. A method for operating a scanning device, Accelerating a transport system in a first direction to move a target region of a sample from a first location to a second location, wherein accelerating the transport system induces vibrational motion in a casing mechanically coupled to the transport system, and the casing is configured to support the transport system. The acceleration causes a reaction force in the second direction and an initial vibrational motion of the casing in the second direction, The method involves slowing down the transport system in the first direction in order to bring the transport system to a stop when the sample is at the second location, The deceleration is to generate a reaction force in the first direction relative to the casing that balances the vibrational motion of the casing in the second direction in order to stop the casing, Methods that include...

15. The method according to claim 13, wherein the motion of the casing includes a plurality of vibration cycles, and the deceleration is timed to occur during a first vibration cycle of the casing.

16. The method according to any one of claims 13 to 14, wherein the casing vibrates at its resonant frequency.

17. A method for generating a motion profile for a scanning device, The method involves providing an impulse to a transport system such that the transport system moves a target area from a first location to a second location, and the movement of the transport system causes the casing of the scanning system to move. The resonant frequency of the casing is measured, Calculating at least one of the acceleration and / or deceleration of the casing based on the aforementioned resonant frequency, To generate a motion profile of the casing based on the calculated acceleration and / or deceleration, Methods that include...

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