CN218585024U - Digital slice rapid focusing system adopting liquid lens - Google Patents

Abstract

The utility model discloses a digital slice quick focusing system adopting a liquid lens, wherein the liquid lens, a left focusing camera and a right focusing camera are arranged in the light path of a digital slice scanner; the liquid lens is arranged between the objective lens and the image capturing camera; the left focusing camera and the right focusing camera are respectively arranged on the left side and the right side of the image capturing camera to acquire focal plane images; the computer processing device is respectively connected with the left focusing camera and the right focusing camera so as to acquire a focal plane signal according to a focal plane image acquired by the left focusing camera or the right focusing camera; the computer processing device is connected with the constant current source driver to send focal plane signals; the constant current source driver is connected with the liquid lens to send different driving currents to control the liquid lens to focus. The utility model discloses increased two and enlarged the camera of focusing (focus camera and the right camera of focusing on a left side) of focusing FOV with obtain the focal plane signal fast, and then control liquid camera lens quick adjustment to the focal plane.

Description

Digital slice rapid focusing system adopting liquid lens

Technical Field

The utility model relates to a microscopic technical field of image scanning specifically relates to an adopt digital section scanning quick focusing system of liquid camera lens.

Background

The digital slice scanner is a precision instrument composed of optics, mechanics, electronics, computers and the like, and has the working principle that a plurality of continuous high-resolution images are obtained by controlling a microscopic imaging system and a slice to move in a certain rule, and then a high-resolution full-slice image (also called a virtual digital slice image) is generated by splicing. The user can store, manage and share the digital picture with high resolution, and the digital picture can be optionally amplified and reduced. The application is widely applied to the fields of pathological diagnosis, teaching and training, medicine research, scientific research and the like.

Along with the popularization of the application, the performance requirements on the scanner are higher and higher, and particularly the scanning quality and speed are improved. To obtain a high-quality image, a camera is required to be accurately focused, and generally, images of thousands of visual fields need to be shot to be spliced into a full-slice image when a slice is digitized, so that the focusing mode is a key factor influencing the scanning speed; whether focusing is accurate or not directly affects the quality of the image.

In the application products of microscope and scanning focusing, the focusing method used at present mostly uses mechanical movement to change the focal plane of the lens for focusing, and also adopts a piezoelectric ceramic driver for focusing. The former can produce mechanical error and backlash error due to the friction and loss of mechanical motion, the processing difficulty is high and is accompanied with larger noise, and the latter has the factors of short adjusting distance, high cost and the like, but cannot be applied to a microscope and a scanner in a large quantity although the response speed is high.

In addition, in the application of the microscope and digital scanning system using a large-area-array camera, one of the methods for increasing the scanning speed is to increase the frame rate of the camera and continuously scan the digital slices, the former can be solved by the camera with a higher frame rate, and the latter depends on the focusing speed.

SUMMERY OF THE UTILITY MODEL

The utility model discloses to the above-mentioned defect of prior art, provide an adopt liquid camera lens's digital section scanning quick focusing system, increased two and enlarged the focusing camera (the camera is focused on a left side and the camera is focused on the right side) of focusing FOV with obtain the focal plane signal fast, and then control liquid camera lens quick adjustment to the focal plane.

The utility model adopts the following technical scheme:

a digital slide fast focusing system using a liquid lens, comprising: a digital slice scanner, a constant current source driver and a computer processing device; the digital slice scanner comprises an objective lens and an image capture camera; a liquid lens, a left focusing camera and a right focusing camera are also arranged in the light path of the digital slice scanner; the liquid lens is arranged between the objective lens and the image capturing camera; the left focusing camera and the right focusing camera are respectively arranged on the left side and the right side of the image capturing camera to acquire focal plane images; the computer processing device is respectively connected with the left focusing camera and the right focusing camera so as to acquire a focal plane signal according to a focal plane image acquired by the left focusing camera or the right focusing camera; the computer processing device is connected with the constant current source driver to send the focal plane signal; the constant current source driver is connected with the liquid lens to send different driving currents to control the liquid lens to focus.

Preferably, the clear aperture of the liquid lens is 5-16mm.

Preferably, the liquid lens is installed between the infinity corrected objective lens and the tube lens.

Preferably, the optical path of the digital slice scanner is divided into three paths by a light splitting device, wherein the three paths are respectively a main optical path, a left optical path and a right optical path; the image-taking camera receives the main optical path in the optical path pipe diameter and forms a digital slice image; the left focusing camera receives the left light path in the light path pipe diameter and forms a left focal plane image; the right focusing camera receives the right optical path in the optical path pipe diameter and forms a right focal plane image; the FOV obtained by the left focusing camera and the right focusing camera is larger than the image taking camera and leads the current FOV by at least one view field.

Preferably, the digital slice scanner further comprises a stage and a support; the object stage is arranged on an X axis; the bracket is arranged on a Y axis; the objective lens, the image capturing camera, the liquid lens, the left focusing camera and the right focusing camera are arranged on a Z axis and are arranged on a Y axis together with an optical path; the Z axis is respectively vertical to the X axis and the Y axis, and the X axis, the Y axis and the Z axis form an orthogonal coordinate system; in the process of focusing by using the liquid lens, the whole Z axis is fixed, the Y axis drives the Z axis to move back and forth, and the X axis moves left and right to perform continuous scanning.

Preferably, the digital slice fast focusing system using a liquid lens further includes: a USB hub; the computer processing device, the image capturing camera, the left focusing camera, the right focusing camera and the constant current source driver are respectively connected with the USB hub through USB lines; the liquid lens is connected with the constant current source driver through a USB wire.

Preferably, the constant current source driver includes an LC low pass filter.

Preferably, the image capturing camera is horizontally arranged; the left focusing camera and the right focusing camera are obliquely arranged.

Preferably, the digital slice scanner further comprises an illumination device; the lighting device provides a light source for collecting digital slice images.

Compared with the prior art, the beneficial effects of the utility model are as follows:

the utility model discloses in digital section scanner, install the automatic focusing liquid lens between getting for instance camera and objective, this liquid lens can carry out fast switch over between different focal length distances, the lens response time is little (if be less than 2.5 ms), add the processing time that gets for instance camera and computer processing apparatus, it is far less than mechanical focusing system to obtain the focal length time, this liquid lens can be equipped with 10 lockable I/O Molex connectors of needle, supply GPIO, the use of trigger (constant current source driver, for short driver), and be connected with the USB concentrator and can realize USB signal transmission; the focusing liquid lens of the utility model can be easily triggered by the computer processing device, can be independently configured to meet the application requirement, and can instantly ensure to obtain a perfect clear image; furthermore, the utility model discloses two cameras of focusing (the camera is focused on the left side and the camera is focused on the right side) have been designed in the light path of digital section scanner, can obtain 2 scanning direction of motion (direction of advance and return direction) the preceding one and above visual field focal plane in advance, provide quick focusing for continuous scanning to reach system's continuous scanning, improve scanning speed's purpose.

The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments thereof taken in conjunction with the accompanying drawings.

Drawings

Fig. 1 is a first structural diagram of a digital slice scanner according to an embodiment of the present invention;

fig. 2 is a second structural diagram of a digital slice scanner according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a liquid lens according to an embodiment of the present invention; wherein, (a) represents a front view; (b) showsbase:Sub>A sectional view A-A; (b) shows a perspective view;

fig. 4 is a schematic view of FOV of an image capturing camera and a focusing camera according to an embodiment of the present invention;

fig. 5 is a schematic connection diagram of components of a digital slice scanning fast focusing system according to an embodiment of the present invention;

fig. 6 is a diagram of the correspondence between different focal plane signals and driving currents according to an embodiment of the present invention;

fig. 7 is a circuit diagram of an LC low-pass filter in a constant current source driver according to an embodiment of the present invention;

fig. 8 shows the settling time after the LC filter is added to the liquid lens according to the embodiment of the present invention;

the attached drawings are as follows: 10. a digital slice scanner; 101. an image capture camera; 102. a left focus camera; 1021. an output port of the left focus camera; 103. a right focus camera; 1031. an output port of the right focus camera; 104. a liquid lens; 1041. an input port of the liquid lens; 105. an objective lens; 106. digital slicing; 107. an object stage; 108. a support; 109. the diameter of the light path; 20. computer processing means; 30. a constant current source driver; 40. a USB hub.

Detailed Description

Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "first", "second", and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically limited otherwise.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted", "disposed", "placed", "contacted", and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

Referring to fig. 1, 2 and 5, a digital slice scan fast focus system using a liquid lens includes: a digital slice scanner 10, a constant current source driver 30 and computer processing means 20; the digital slide scanner 10 includes an objective lens 105 and a camera 101; in the optical path of the digital slice scanner 10, a liquid lens 104, a left focus camera 102 and a right focus camera 103 are also installed; the liquid lens 104 is installed between the objective lens 105 and the image capture camera 101; the left focusing camera 102 and the right focusing camera 103 are respectively installed at the left side and the right side of the image capturing camera 101 to acquire focal plane images; the computer processing device 20 is connected with the left focusing camera 102 and the right focusing camera 103 respectively, so as to acquire a focal plane signal according to a focal plane image acquired by the left focusing camera 102 or the right focusing camera 103; the computer processing means 20 is connected to the constant current source driver 30 to transmit the focal plane signal; the constant current source driver 30 is connected to the liquid lens 104 to send different driving currents to control the liquid lens 104 to focus.

In this embodiment, the left focusing camera 102 and the right focusing camera 103 are installed on the left and right of the optical path, so that the digital slice scanner 10 can be ensured to continuously scan the whole object surface back and forth in the continuous scanning process. In addition, the left focusing camera 102 or the right focusing camera 103 obtains two or more focal plane images of the FOV at a time and sends the images to the computer processing device 20, the computer processing device 20 continuously compares the previous focal plane signal or signals with the current focal plane signal and then sends the generated deviation signal to the constant current source driver 30, and the constant current source driver 30 generates different driving currents to drive the liquid lens 104, so that the image capturing camera 101 obtains a correct focal plane.

The liquid lens 104 is based on the following principle: the lens consists of a container and an elastic polymer film covered on the container, wherein the container is filled with optical fluid, and the deformation (bending) of the lens is proportional to the pressure applied to the fluid. The lens has an electromagnetic actuator for applying pressure. Thus, the focal length of the lens is controlled by the current flowing through the electromagnetic actuator coil. More precisely, a new type of optical element that dynamically adjusts the refractive index of a lens or changes the focal length by changing its own curvature, is called a solid-state AF system because there are no moving parts.

Advantages of the liquid lens 104 include: firstly, as for the uncertainty of the optical lens, the liquid lens 104 with quantifiable pure electric circuit is more accurate in focusing and more accurate in optical data; secondly, it can achieve rapid switching of different focal lengths within a few milliseconds, which is undoubtedly an ideal component of an auto-focus system; third, since the lens itself does not have any moving parts, it is more resistant to vibration, shock.

In this embodiment, the clear aperture of the liquid lens 104 is 5-16mm. The larger the clear aperture is, the better, the embodiment takes a 10mm clear aperture as an example, the liquid lens 104 of the oportune corporation is adopted as the liquid lens 104 of the embodiment, and a specific structure diagram is shown in fig. 3.

Specifically, the liquid lens 104 is installed between the infinity corrected objective lens 105 and the tube lens. This configuration also requires that the liquid lens 104 have (include) an infinite focal length. By changing the current on the liquid lens 104 by the constant current source driver 30, the focal length of the image pickup camera 101 to the slice can be changed.

The optical path of the digital slice scanner 10 is divided into three paths by a light splitting device (not shown in the figure), which are a main optical path, a left optical path and a right optical path; the image capture camera 101 receives the main light path in the light path pipe diameter 109 and forms a digital slice image; the left focus camera 102 receives the left optical path in the optical path pipe diameter 109 and forms a left focal plane image; the right focus camera 103 receives the right optical path in optical path tube diameter 109 and forms a right focal plane image.

Referring to fig. 4, the left focusing camera 102 and the right focusing camera 103 can obtain at least one FOV adjacent to the FOV of the image capturing camera 101 in different moving directions, that is, the FOV obtained by the left focusing camera 102 and the right focusing camera 103 is larger than the FOV of the image capturing camera 101 and is ahead of the current FOV by at least one field of view, so as to obtain the previous focal plane or focal planes.

Specifically, in the digital slice scanner 10, during the continuous scanning process, the left focusing camera 102 works in the forward direction, and the right focusing camera 103 works in the backward direction; or, the right focusing camera 103 works in the forward direction, and the left focusing camera 102 works in the backward direction, that is, the focal lengths in different directions are obtained in the back and forth continuous scanning, so that the accuracy of the continuous scanning focusing is ensured.

Further, the digital slice scanner 10 further includes an object stage 107 and a support 108; the stage 107 is mounted on the X-axis; the bracket 108 is mounted on the Y axis; the objective lens 105, the image capture camera 101, the liquid lens 104, the left focusing camera 102 and the right focusing camera 103 are arranged on the Z axis and are arranged on the Y axis together with the optical path; the Z axis is respectively vertical to the X axis and the Y axis, and the X axis, the Y axis and the Z axis form an orthogonal coordinate system; during focusing using the liquid lens 104, the entire Z-axis is fixed without any mechanical movement, and the Y-axis drives the Z-axis back and forth. In addition, the Z axis can be fixed, and the continuous scanning can be performed by the left-right movement of the X axis.

Referring to fig. 5, the digital slice scanning fast focusing system using a liquid lens further includes: a USB hub 40; the computer processing device 20, the image capturing camera 101, the left focusing camera 102, the right focusing camera 103 and the constant current source driver 30 are respectively connected with the USB hub 40 through USB lines; the liquid lens 104 is connected to the constant current source driver 30 through a USB cable.

Specifically, the output port 1021 of the left focus camera and the output port 1031 of the right focus camera are respectively connected to the computer processing device 20. The USB3.0 input port (or 2.0) of the constant current source driver 30 is connected to a USB hub 40 and to the computer processing device 20. The output port of the constant current source driver 30 is connected to the input port 1041 of the liquid lens via a USB cable. After the focusing camera acquires the focal plane image, the focal plane image is sent to the computer processing device 20, the analyzed focal plane signal is transmitted to the input port of the constant current source driver 30 through the USB3.0 interface of the USB hub 40 through scanning software and calculation processing, and the driving current of the constant current source driver 30 is input to the liquid lens 104 through a cable, so that the focal length of the optical system is changed rapidly, and the purpose of focusing is achieved. In this embodiment, the liquid lens 104 is connected to the constant current source driver 30 through a dedicated wire/dedicated connector, and may be specifically equipped with a 10-pin lockable I/O Molex connector. Of course, in other embodiments, a connection wire or connector may be provided, which may be selected according to the specific application, as long as the liquid lens 104 and the constant current source driver 30 can communicate with each other.

The correspondence between different focal plane signals and drive currents is shown in fig. 6, in which the coordinates of the drive current signals and the coordinates of the focal plane change direction are put together. As can be seen from fig. 6, the drive current is proportional to the focal plane signal. Setting the driver current to some initial value E, and adjusting the optical system to make the focal plane at the lowest point M in the opposite direction; when the current of the driver is the maximum Q point, the focal plane is enabled to be at the highest point N of the positive direction; when the driver current is P point, the focal plane is at the center of O point.

In addition, in this embodiment, during the scanning process of the same digital slice, the left focusing camera 102 or the right focusing camera 103 collects a focal plane image and sends the focal plane image to the computer processing device 20, and the computer processing device 20 performs analysis and calculation on the focal plane, performs deep learning on the characteristic parameters and the focusing factors of the tissue structure of the focal plane image to obtain one or more sets of focal plane reference values, and retains the one or more sets of focal plane reference values to provide a driving signal for rapidly obtaining the focal plane for the next slice or the next slice. Specifically, a focal plane image of a section sample is obtained through the left focusing camera 102 and the right focusing camera 103, the focal plane image is sent to application software of the computer processing device 20 to analyze the image, a focusing curve of the image is calculated, then a peak value of the focusing curve is obtained through fitting, and the position from the Z axis to a reference line is adjusted according to the corresponding relation between the peak value obtained through calibration and the Z axis, so that the focusing process of the focusing camera is completed.

In summary, according to the design requirements of the optical system and the optical characteristics of the liquid lens 104, firstly, the liquid lens 104 is installed in the optical path having (including) the infinite focal length; secondly, in order to continuously scan and focus the digital slices in a certain area back and forth, two paths of light splitting are separated from a main light path and are supplied to the left and right focusing cameras 103 for use; the whole optical path system comprises an image capturing camera 101, two focusing cameras, a liquid lens 104, an objective lens 105 and other optical elements. In addition, an illumination device is also installed, which is a light source of the digital slice 106. The objective lens 105 is used to observe the illuminated portion of the digital slide 106; the constant current source driver 30, which is connected to the computer processing device 20, is connected to the liquid lens 104 through a cable.

The control process of the digital slice scanning rapid focusing system adopting the liquid lens in the implementation is as follows:

1) The slice sample is placed on an object stage of the system, an illuminating device is started, at least one focal plane image is obtained by focusing cameras (a left focusing camera and a right focusing camera) on a Z axis and is sent to a computer processing device, a focal plane signal is obtained after calculation of application software and is transmitted to a constant current source driver through a USB interface to be converted into current in a certain proportion, and the current drives a liquid lens and obtains a focal plane which is obtained after calculation and is consistent with the focal plane signal. The time generated in the whole focusing process is very short, and the liquid lens can finish focusing only within 3-5mS after obtaining a focal plane driving signal.

2) Assuming that the Y-axis moving direction starts to scan continuously from back to front, when the image capturing camera obtains a first focal plane, the left focusing camera obtains two FOV field-of-view focal plane signals, the latter focal plane signal is provided for the image capturing camera so as to obtain the focal plane of the next image, after the image capturing camera finishes the current image capturing, the Y-axis moves forwards by one FOV, and the focal plane of the FOV is obtained in the FOV of the previous focusing camera, so that the image capturing camera can continuously obtain the focal plane of the latter FOV. In cycles, the continuous scanning process of focusing in advance and acquiring the focal plane can be completed.

3) When the Y-axis moves to the interface set by the software, the X-axis moves one FOV to the left (or right) and the Y-axis motion will change direction, i.e. the Y-axis motion direction is scanned continuously from front to back. At this time, the right focusing camera will work due to the direction change, and the task of focusing in advance is completed. The working process of the system is the same as the working process of the system 2) until the scanning of the scanning area set by the software is finished.

In the embodiment, the liquid lens focusing device is adopted, so that a focusing part and a stepping motor of a scanning system are omitted, and the optical axis is lightened. In the whole scanning process, the system vibration is improved, and the system stabilization time is greatly shortened. While also improving image quality.

In addition, in order to improve the stability of the whole system, the constant current source driver is also improved, specifically, as shown in fig. 6, an LC low pass filter is added in order to make the rising time of the driving current coincide with the liquid lens stability time.

Specifically, the impedance of the LC low-pass filter may be designed to be equal to the impedance of the selected liquid lens. The rising time of the current of the constant current source is 2-3mS, the stabilization time of the liquid lens is 5mS, and the driving time of the constant current source after the LC low-pass filter is added can be consistent with the stabilization time of the liquid lens through calculation and multiple test results. Referring to fig. 7, the settling time after adding the LC filter to the liquid lens is shown. As can be seen from the figure, the liquid lens reaches more than 90% of the stability, and only needs about 5 mS.

The above-mentioned be the utility model discloses a concrete implementation way, nevertheless the utility model discloses a design concept is not limited to this, and the ordinary use of this design is right the utility model discloses carry out immaterial change, all should belong to the act of infringement the protection scope of the utility model.

Claims (9)

1. A digital slice fast focusing system using a liquid lens, comprising: a digital slice scanner, a constant current source driver and a computer processing device; the digital slice scanner comprises an objective lens and an image capturing camera; a liquid lens, a left focusing camera and a right focusing camera are also arranged in the light path of the digital slice scanner; the liquid lens is arranged between the objective lens and the image capturing camera; the left focusing camera and the right focusing camera are respectively arranged on the left side and the right side of the image capturing camera to acquire focal plane images; the computer processing device is respectively connected with the left focusing camera and the right focusing camera so as to acquire a focal plane signal according to a focal plane image acquired by the left focusing camera or the right focusing camera; the computer processing device is connected with the constant current source driver to send the focal plane signal; the constant current source driver is connected with the liquid lens to send different driving currents to control the liquid lens to focus;

the light path of the digital slice scanner is divided into three paths by a light splitting device, wherein the three paths are respectively a main light path, a left light path and a right light path; the image capturing camera receives the main light path in the light path pipe diameter and forms a digital slice image; the left focusing camera receives the left light path in the light path pipe diameter and forms a left focal plane image; the right focusing camera receives the right optical path in the optical path pipe diameter and forms a right focal plane image; the FOV acquired by the left focusing camera and the right focusing camera is larger than the image taking camera and leads the current FOV by at least one view field; and the computer processing device continuously compares the previous or more than one focal plane signal with the current focal plane signal and then sends the generated deviation signal to the constant current source driver.

2. The system as claimed in claim 1, wherein the clear aperture of the liquid lens is 5-16mm.

3. The digital slice fast focusing system using a liquid lens according to claim 1, wherein the liquid lens is installed between the infinity corrected objective lens and the tube lens.

4. The digital slice fast focusing system adopting a liquid lens as claimed in claim 1, wherein the optical path of the digital slice scanner is split into three paths by a beam splitter, namely a main optical path, a left optical path and a right optical path; the image-taking camera receives the main optical path in the optical path pipe diameter and forms a digital slice image; the left focusing camera receives the left light path in the light path pipe diameter and forms a left focal plane image; the right focusing camera receives the right optical path in the optical path pipe diameter and forms a right focal plane image; the FOV obtained by the left focusing camera and the right focusing camera is larger than the image taking camera and leads the current FOV by at least one view field.

5. The digital slide fast focusing system using liquid lens as claimed in claim 1, wherein said digital slide scanner further comprises a stage and a support; the object stage is arranged on an X axis; the bracket is arranged on a Y axis; the objective lens, the image capturing camera, the liquid lens, the left focusing camera and the right focusing camera are arranged on a Z axis and are arranged on a Y axis together with an optical path; the Z axis is respectively vertical to the X axis and the Y axis, and the X axis, the Y axis and the Z axis form an orthogonal coordinate system; in the process of focusing by using the liquid lens, the whole Z axis is fixed, the Y axis drives the Z axis to move back and forth, and the X axis moves left and right to perform continuous scanning.

6. The digital slide fast focusing system using liquid lens as claimed in claim 1, further comprising: a USB hub; the computer processing device, the image capturing camera, the left focusing camera, the right focusing camera and the constant current source driver are respectively connected with the USB hub through USB lines; the liquid lens is connected with the constant current source driver.

7. The digital slide fast focusing system using liquid lens of claim 1, wherein said constant current source driver comprises an LC low pass filter.

8. The system as claimed in claim 1, wherein the image capturing camera is horizontally disposed; the left focusing camera and the right focusing camera are obliquely arranged.

9. The system of claim 1, wherein the digital slide scanner further comprises an illumination device; the lighting device provides a light source for collecting digital slice images.

Images