Automatic focusing device and method for optical microscope
By designing the combination of incident light mechanism, sensor and motor in the microscope, and using image information to perform automatic focus adjustment, the problem that microscopes with multi-layer imaging surface samples cannot be automatically focused, and remote, fast and clear observation and image amplification are achieved Function.
Patent Information
- Application Number
- CN202110544840.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-05-19
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2041-05-19
AI Technical Summary
Existing microscopes cannot achieve autofocus when processing multi-layer imaging surface samples, resulting in low observation efficiency and poor image clarity, which is difficult to solve especially when remote focus is required.
An automatic focusing device for an optical microscope is designed, including an incident light mechanism, a sensor and a motor. By controlling the processor to analyze image information, the movement direction and distance of the microscope or stage are determined, and the focus adjustment is achieved. The incident beam is focused on the multi-layer imaging surface sample, the sensor receives the reflected beam, and the control processor controls the motor to adjust according to the image information until the correct imaging surface is reached.
Remote, fast and clear observation and image amplification of multi-layer imaging surface samples are realized, solving the problem of automatic focus of multi-layer imaging surface samples in the prior art, and improving the automation and intelligence level of microscopes.
Smart Images
Figure CN115390233B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of instruments and meters, and in particular to an automatic focusing device and method for an optical microscope. Background Art
[0002] Microscope is an important instrument for product quality and performance testing in many industries. It is widely used in various scientific research, teaching practice, production quality testing and other fields. General microscopic testing is based on manually adjusting the focus system of the microscope, and repeated manual operations until the focus position of the object to be tested is adjusted. Such a process takes a long time and is inefficient. In addition, the personnel must be next to the microscope and cannot adjust it remotely.
[0003] As people's requirements for automation and intelligence of microscopes increase, autofocus technology becomes more and more important, especially in some occasions where people need to leave. This requires a microscope that can quickly adjust the focus remotely. Autofocus is a method that uses the principle of light reflection from objects. The light image reflected by the sample is received by the sensor CCD / CMOS on the camera, and then processed by the computer to drive the electric focus device to focus.
[0004] In the current field of microscope applications, how to ensure the clarity of the image is the key. During the focusing process of the microscope, background objects other than the sample will seriously interfere with the image of the sample, causing the sample to form a multi-layer object. Based on the existing autofocus technology, it can be easily focused on a single-layer imaging surface sample, which is widely used in machine vision, camera imaging, remote sensing radar and other aspects. In addition to single-layer imaging surface samples, there is also a multi-layer imaging surface sample, such as thin film transistor TFT, multi-layer PCB circuit board, etc. In the current field of microscope applications, the microscope autofocus technology of multi-layer imaging surface samples is still a difficult problem that the majority of scientific research staff need to overcome. The above-mentioned "imaging surface" refers to the surface on the sample that can be imaged. If the sample under test has only one imaging surface when observed under a microscope (the upper and lower surfaces of the sample do not affect each other, that is, only the upper surface is observed), the upper surface of the sample under test serves as the imaging surface and also as the imaging surface to be observed, then the sample under test is called a single-layer imaging surface sample; a multi-layer imaging surface sample is a sample under test with more than or equal to 2 imaging surfaces. At this time, the upper and lower surfaces of the sample under test usually affect the microscopic imaging results of the sample under test, so the upper and lower surfaces are respectively called a layer of imaging surface. Summary of the invention
[0005] In order to solve the problem that a microscope of a multi-layer imaging surface sample cannot achieve auto-focusing, the present invention provides an auto-focusing device and method for an optical microscope.
[0006] The technical solution adopted by the present invention to solve the technical problem is as follows:
[0007] The automatic focusing device of an optical microscope comprises: an incident light mechanism, a sensor, a motor and a control processor, wherein the control processor is connected to the sensor and the motor, and the operation of the motor can drive the microscope objective lens of the microscope or a stage for placing a multi-layer imaging surface sample to move; the light beam emitted by the incident light mechanism can be incident on the microscope objective lens, and the microscope objective lens can focus the light beam incident thereon by the incident light mechanism onto the multi-layer imaging surface sample, and the light beam focused on the multi-layer imaging surface sample can be imaged onto the focal plane of the sensor after being reflected by the multi-layer imaging surface sample so that the sensor obtains image information, and the sensor can send the image information to the control processor; the control processor can judge the focus status of the microscope according to the image information, and if the microscope has not completed the focus, the control processor controls the operation of the motor according to the image information.
[0008] The focusing method of the automatic focusing device of the optical microscope comprises the following steps:
[0009] S1, the control processor analyzes and determines whether the microscope objective lens is focused on the correct imaging surface of the multi-layer imaging surface sample according to the image data sent by the sensor. If the microscope objective lens is focused on the correct imaging surface, the automatic focusing of the optical microscope is completed, otherwise, proceed to S2;
[0010] S2. The control processor determines the moving direction and moving distance of the microscope objective lens or the stage according to the image information and the correct imaging plane, and sends a moving signal to the motor according to the moving direction and moving distance. The motor moves according to the moving signal and then moves the microscope objective lens or the stage, and returns to S1.
[0011] The beneficial effects of the present invention are:
[0012] The optical microscope autofocus device and method of the present invention solve the problem of remote, fast and clear observation of samples with multi-layer imaging surfaces. The present invention uses optical imaging technology to intuitively adapt to the development of microscopic magnification detection technology of multi-layer imaging surface samples, and provides a new optical microscope autofocus method and device, which realizes the microscope autofocus of multi-layer imaging surface samples, and realizes the remote, fast and clear image magnification function of samples with multi-layer imaging surfaces under an optical microscope. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 The figure is a schematic diagram of the optical path system of the automatic focusing device of the optical microscope of the present invention.
[0014] Figure 2 The diagram is a schematic diagram of the optical path of the first transmitted light of the automatic focusing device of the optical microscope of the present invention at different positions on the sample surface through the microscope objective lens.
[0015] Figure 3The figure is a schematic diagram of images formed at different positions on the sample surface by the first transmitted light of the automatic focusing device of the optical microscope of the present invention through the microscope objective lens.
[0016] Figure 4 The present invention is a flow chart of a focusing method of an automatic focusing device for an optical microscope.
[0017] Figure 5 It is the automatic focusing imaging result of the multi-layer imaging surface sample of the automatic focusing device of the optical microscope of the present invention.
[0018] In the figure: 1. Laser, 2. Collimating beam expander, 3. Aperture, 4. Half-reflecting half-mirror, 5. Collector, 6. Microscope objective, 7. Multi-layer imaging surface sample, 8. Stage, 9. Imaging lens, 10. Sensor, 11. Motor, 12. Control processor. DETAILED DESCRIPTION
[0019] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.
[0020] The automatic focusing device of the optical microscope for the multi-layer imaging surface sample 7 comprises an incident light mechanism, a sensor 10, a motor 11 and a control processor 12, wherein the control processor 12 is connected to the sensor 10 and the motor 11, and the motor 11 is connected to the stage 8 of the microscope or the microscope objective lens 6 of the microscope, and the stage 8 is used to place the sample, and the sample is the multi-layer imaging surface sample 7. The motor 11 can drive the stage 8 or the microscope objective lens 6 to move. The control processor 12 can receive the image information sent by the sensor 10 and control the movement of the motor 11 accordingly, and drive the stage 8 or the microscope objective lens 6 to move through the movement of the motor 11, and complete the focusing of the optical microscope through the movement of the stage 8 or the microscope objective lens 6. The incident light mechanism emits a light beam, the light beam emitted by the incident light mechanism is incident on the microscope objective lens 6, and after being focused by the microscope objective lens 6, it is incident on the multi-layer imaging surface sample 7, the multi-layer imaging surface sample 7 reflects the light beam, and the light beam reflected by the multi-layer imaging surface sample 7 is imaged onto the focal plane of the sensor 10, and the sensor 10 obtains image information, and the sensor 10 sends the obtained image information to the control processor 12, the control processor 12 receives the image information sent by the sensor 10 and performs analysis and processing based on the image information to obtain an analysis result, and the control processor 12 controls the movement of the motor 11 according to the analysis result to realize the focusing of the optical microscope.
[0021] The incident light mechanism includes a laser 1, a collimating beam expander 2 and an aperture 3 which are arranged in sequence. The light beam emitted by the laser 1 is collimated and expanded by the collimating beam expander 2 to obtain a collimated light beam. The collimated light beam is limited by the aperture 3 and then irradiated to the microscope 6. The shape and area of the outgoing light beam of the half-side light beam of the collimated light beam after passing through the aperture 3 are different from those of the outgoing light beam of the other half-side light beam of the collimated light beam after passing through the aperture 3, that is, the shape and area of the beam cross section are different. Preferably, the aperture 3 adopts a rectangular aperture, and the half-side light beam of the collimated light beam can pass through the rectangular aperture, while the other half-side light beam cannot pass through the rectangular aperture or can only partially pass through the rectangular aperture. The image formed by the imaging surface located above the focus of the microscope 6 in the multi-layer imaging surface sample 7 on the sensor 10 is different from the image formed by the imaging surface located below the focus of the microscope 6 on the sensor 10. The purpose is to judge how to adjust the microscope 6 or the stage 8 according to the different images of the imaging surfaces located above and below the focus of the microscope 6. In this embodiment, the spot of the collimated light beam is a circular spot, and the image obtained by the sensor 10 imaging the multi-layer imaging surface sample 7 includes a non-closed circular ring. The aperture 3 in the optical path divides the light beam after passing through the collimating beam expander 2 into two equal parts, that is, after passing through the aperture 3, only 1 / 2 of the collimated light beam passes through the aperture 3, and half of the collimated light beam can pass through the aperture 3, while the other half of the light beam cannot pass through the aperture 3. For example, only the left half, the right half, the upper half or the lower half passes through the aperture 3 and is irradiated onto the microscope objective 6. Figure 1 In the figure, the right half of the collimated light beam is blocked by the aperture 3, and the left half passes through the aperture 3. The image obtained by the sensor 10 imaging the multi-layer imaging surface sample 7 includes a semicircular ring.
[0022] The autofocus device also includes a semi-reflective mirror 4, a light collector 5, and an imaging lens 9. Figure 1 , laser 1, collimating beam expander 2, aperture 3, half-reflecting half-mirror 4, microscope objective 6, multi-layer imaging surface sample 7 and stage 8 are arranged in sequence, imaging lens 9 is located between half-reflecting half-mirror 4 and sensor 10, and light collector 5 is arranged adjacent to half-reflecting half-mirror 4 for collecting the first reflected light beam described below. After the collimated light beam passes through aperture 3, it is incident on half-reflecting half-mirror 4, and is transmitted and reflected on half-reflecting half-mirror 4 to obtain a first transmitted light beam and a first reflected light beam. The first reflected light beam is collected by light collector 5, and the first transmitted light beam is incident on microscope objective 6, and is collected on multi-layer imaging surface sample 7 through microscope objective 6, and is reflected on multi-layer imaging surface sample 7 to obtain a second reflected light beam. After the second reflected light beam is converged through microscope objective 6, it is incident on half-reflecting half-mirror 4, and is transmitted through half-reflecting half-mirror 4 to obtain a second transmitted light beam and reflected to obtain a third reflected light beam. The second transmitted light beam is no longer used by the present invention. Figure 1Not shown, the third reflected light beam is incident on the imaging lens 9, and after being converged by the imaging lens 9, it forms an image on the sensor 10, and the sensor 10 obtains image information. The multi-layer imaging surface sample 7 is located in the object plane of the microscope objective lens 6, and the object plane of the microscope objective lens 6 and the focal plane of the sensor 10 are in an imaging relationship.
[0023] Figure 2 It is a schematic diagram of the positions of a, b, c, d, and e on the surface of the multi-layer imaging surface sample 7 through the microscope objective lens 6, wherein c is located at the focus of the microscope objective lens 6, a is located above b, and b is above the focus of the microscope objective lens 6; e is located below d, and d is below the focus of the microscope objective lens 6.
[0024] Figure 3 The figure is a schematic diagram of the images formed by the light beam passing through the microscope objective lens 6 on the surfaces a, b, c, d, and e of the multi-layer imaging surface sample 7. The image of c is a dot; the images of a, b, d, and e are all semicircular rings. a and b are above the focus of the microscope objective lens 6, and the semicircular rings of the two images are both opened to the right, and the semicircular ring diameter of a is larger than the semicircular ring diameter of b; d and e are below the focus of the microscope objective lens 6, and the semicircular rings of the two images are both opened to the left (opposite to the opening direction of a and b), and the semicircular ring diameter of e is larger than the semicircular ring diameter of d. The light divided into two equal parts by the aperture 3 forms different images at different positions on the optical axis after passing through the microscope objective lens 6: along the direction of light transmission, the images formed at the positions on both sides of the focus are rotationally symmetrically distributed along the focus and in opposite directions.
[0025] An automatic focusing method for an optical microscope based on an automatic focusing device for an optical microscope, such as Figure 4 As shown, the following steps are included:
[0026] The multi-layer imaging surface sample 7 is placed on the stage 8. After selecting the microscope objective lens 6 with a suitable magnification, the microscope moves and resets. The microscope objective lens 6 can focus the light beam incident on it by the incident light mechanism onto the multi-layer imaging surface sample 7. The microscope objective lens 6 can be an optical magnification system with different magnifications such as 5X, 10X, 20X, and 50X. The sensor 10 is used to receive a series of images reflected from the surface of the multi-layer imaging surface sample 7, and can be a linear array or area array CCD or CMOS. The motor 11 adopts a servo motor.
[0027] Step 1: The focusing operator remotely turns on the incident light mechanism, the sensor 10, the motor 11 and the control processor 12, confirms that the microscope objective lens 6 can focus the light beam incident on it by the incident light mechanism onto the multi-layer imaging surface sample 7, and determines the correct imaging surface of the microscope objective lens 6 on the multi-layer imaging surface sample 7 (the correct imaging surface is the target surface). The focusing operator can remotely determine the correct imaging surface of the multi-layer imaging surface sample 7 focused on by the microscope objective lens 6, and determine the correct imaging surface of the multi-layer imaging surface sample 7 focused on by the microscope objective lens 6 on the control processor 12. The incident light mechanism irradiates the multi-layer imaging surface sample 7, and the sensor 10 obtains image data by imaging and sends it to the control processor 12.
[0028] Step 2: The control processor 12 analyzes and determines the image data sent by the sensor 10 to determine whether the microscope lens 6 is focused on the correct imaging surface of the multi-layer imaging surface sample 7. If the microscope lens 6 is focused on the correct imaging surface, the automatic focusing of the optical microscope is completed. Otherwise, the microscope lens 6 has not been focused on the target surface, and step 3 is performed.
[0029] Step three, the control processor 12 determines the moving direction and moving distance of the microscope objective lens 6 or the stage 8 according to the image information and the target surface, and sends a moving signal to the servo motor according to the moving direction and moving distance. The servo motor moves the microscope objective lens 6 or the stage 8, and the sensor 10 obtains new image data and sends it to the control processor 12, and returns to step two to re-analyze and determine whether the microscope objective lens 6 is focused on the correct imaging surface.
[0030] Figure 5 The multi-layer imaging surface sample 7 has four layers of imaging surfaces, which are top (top imaging surface), layer1 (first middle imaging surface), layer2 (second middle imaging surface), and bottle (bottom imaging surface) along the light transmission path. Figure 5 The automatic focusing imaging result of the correct imaging surface layer1 of the multi-layer imaging surface sample 7 is illustrated by way of example.
[0031] The advantages of the present invention are as follows: the present invention utilizes optical imaging technology to intuitively adapt to the development of microscopic magnification detection technology of multi-layer imaging surface samples 7. Through the present invention, the image magnification function of samples with multi-layer imaging surfaces under an optical microscope can be realized remotely, quickly and clearly.
[0032] The present invention mentions an automatic focusing device and method for an optical microscope, which solves the problem of remote, fast and clear observation of a sample 7 with a multi-layer imaging surface. The present invention uses optical imaging technology to intuitively adapt to the development of microscopic magnification detection technology for a sample 7 with a multi-layer imaging surface, and provides a new automatic focusing method and device for an optical microscope, which realizes the automatic focusing of a microscope for a sample 7 with a multi-layer imaging surface, and realizes the remote, fast and clear image magnification function of a sample 7 with a multi-layer imaging surface under an optical microscope.
[0033] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.
Claims
1. Automatic focusing device for optical microscope, It is characterized in that include: An incident light mechanism, a sensor (10), a motor (11) and a control processor (12); the control processor (12) is connected to the sensor (10) and the motor (11); the operation of the motor (11) can drive the microscope objective lens (6) of the microscope or a stage (8) for placing a multi-layer imaging surface sample (7) to move; the light beam emitted by the incident light mechanism can be incident on the microscope objective lens (6); the microscope objective lens (6) can focus the light beam incident on it by the incident light mechanism onto the multi-layer imaging surface sample (7); the light beam focused on the multi-layer imaging surface sample (7) can be imaged onto the focal plane of the sensor (10) after being reflected by the multi-layer imaging surface sample (7), so that the sensor (10) obtains image information; the sensor (10) can send the image information to the control processor (12); the control processor (12) can determine the focus status of the microscope according to the image information; if the microscope has not completed the focus, the control processor (12) controls the operation of the motor (11) according to the image information; The incident light mechanism comprises a laser (1), a collimating beam expander (2) and an aperture (3) which are arranged in sequence. The light beam emitted by the laser (1) is collimated and expanded by the collimating beam expander (2) to obtain a collimated light beam. The collimated light beam is limited by the aperture (3) and then irradiated onto a microscope objective lens (6). After passing through the aperture (3), the half side light beam and the other half side light beam of the collimated light beam have different beam shapes and areas.
2. The automatic focusing device for an optical microscope according to claim 1, It is characterized in that The aperture (3) is a rectangular aperture, half of the collimated light beam can pass through the aperture (3), and the other half of the light beam cannot pass through the aperture (3) or can only partially pass through the aperture (3).
3. The automatic focusing device for an optical microscope as claimed in claim 2, It is characterized in that The aperture (3) is a rectangular aperture (3), half of the side beam of the collimated light beam can pass through the aperture (3), and the other half of the side beam cannot pass through the aperture (3).
4. The automatic focusing device for an optical microscope according to claim 1, It is characterized in that The autofocus device further comprises a semi-reflective half-mirror (4) and an imaging lens (9), wherein a collimating beam expander (2), an aperture (3), a semi-reflective half-mirror (4) and a microscope objective lens (6) are arranged in sequence, and the imaging lens (9) is located between the semi-reflective half-mirror (4) and a sensor (10); the collimated light beam passes through the aperture (3) and is incident on the semi-reflective half-mirror (4), and is transmitted through the semi-reflective half-mirror (4) to obtain a first transmitted light beam; the first transmitted light beam is incident on the microscope objective lens (6), and is collected on a multi-layer imaging surface sample (7) through the microscope objective lens (6), and is reflected on the multi-layer imaging surface sample (7) to obtain a second reflected light beam; the second reflected light beam is collected through the microscope objective lens (6), and is reflected by the semi-reflective half-mirror (4) and collected by the imaging lens (9) in sequence, and is imaged on the sensor (10), and the sensor (10) obtains image information.
5. The automatic focusing device for an optical microscope according to claim 1, It is characterized in that The image formed on the sensor (10) by the target layer located above the focus of the microscope objective lens (6) in the multi-layer imaging surface sample (7) is different from the image formed on the sensor (10) by the target layer located below the focus of the microscope objective lens (6).
6. The automatic focusing device for an optical microscope according to claim 1, It is characterized in that The light beam is reflected by the multi-layer imaging surface sample (7), converged by the microscope objective lens (6), and then imaged onto the focal plane of the sensor (10).
7. The focusing method of the automatic focusing device of the optical microscope according to any one of claims 1 to 6, It is characterized in that The steps include: S1, the control processor (12) determines whether the microscope objective lens (6) is focused on the correct imaging surface of the multi-layer imaging surface sample (7) according to the image data sent by the sensor (10). If the microscope objective lens (6) is focused on the correct imaging surface, the automatic focusing of the optical microscope is completed; otherwise, S2 is performed; S2, the control processor (12) determines the moving direction and moving distance of the microscope objective lens (6) or the stage (8) according to the image information and the correct imaging surface, and sends a moving signal to the motor (11) according to the moving direction and moving distance. The motor (11) moves according to the moving signal and thus moves the microscope objective lens (6) or the stage (8), and returns to S1.
8. The focusing method of the automatic focusing device of the optical microscope according to claim 7, It is characterized in that Before S1 is performed, the following steps are also included: turning on the incident light mechanism, the sensor (10), the motor (11) and the control processor (12), confirming that the microscope objective lens (6) can focus the light beam incident on it by the incident light mechanism onto the multi-layer imaging surface sample (7), and determining the correct imaging surface of the microscope objective lens (6) on the multi-layer imaging surface sample (7).