Objective lens converter and rotation positioning method thereof

Abstract

The objective lens converter comprises a rotating disc used for installing an objective lens, the upper surface of the rotating disc is provided with an annular upper groove used for containing a ball, the lower surface of the rotating disc is provided with an annular lower groove used for containing the ball, and the rotating disc is provided with an initial position flag bit; the upper cover is arranged above the turntable and is provided with an annular cover plate groove and an inner annular flange; an output shaft of the stepping motor is directly coupled with the center of the turntable; a mounting hole is formed in the base, and an annular guide rail is arranged on the base; the magnetic encoder is installed on the stepping motor and used for controlling the rotation angle of the stepping motor; the first photoelectric switch sensor is mounted in the cover plate groove of the upper cover; and the second photoelectric switch sensor is arranged in the cover plate groove of the upper cover. According to the invention, the response speed and positioning precision of objective lens conversion are improved.

Description

Technical Field

[0001] The invention relates to an objective lens converter for a microscope, in particular to an objective lens converter and a rotation positioning method thereof. Background Art

[0002] In modern microscopy technology, the efficiency and accuracy of the objective lens switching system are crucial to improving research and detection efficiency. The traditional manual method of replacing the objective lens is not only time-consuming and laborious, but may also cause unnecessary physical damage to the precision optical components, affecting the image quality. Therefore, the electric objective turret came into being. It uses a motor drive to achieve fast and smooth switching of the objective lens, significantly improving the convenience of operation and work efficiency.

[0003] Although the existing electric objective lens converter has solved the inconvenience of manual operation to a certain extent, there are still some areas to be optimized. For example, the response speed and positioning accuracy of most products on the market still have room for improvement, especially in situations where the objective lens needs to be frequently switched to adapt to different observation needs (such as from bright field to fluorescence imaging). In addition, some high-end microscope applications, such as real-time cell imaging and FRET (fluorescence resonance energy transfer) experiments, have extremely high requirements for the speed and synchronization of objective lens switching. The ability of traditional electric wheels to complete precise switching in a very short time is limited, which may cause the continuity and reliability of experimental data to be damaged.

[0004] In addition, although the traditional electric objective lens conversion system has been widely adopted, most of them rely on indirect motor drive, which, while achieving fast and accurate positioning, also faces problems such as heat generation, low efficiency and limited dynamic performance. Especially in complex experimental environments where observation modes need to be frequently changed, these limitations of the indirect drive structure are particularly prominent. In view of this situation, the direct use of stepper motors to drive the turntable has become an innovative attempt to reduce the transmission links and improve the response speed and reliability of the system. For example, the Chinese patent application number CN202311367792.1 discloses "A kind of electric objective lens converter and a method for improving positioning accuracy". Although this type of direct drive method improves the simplicity and responsiveness of the system, it puts higher requirements on the control accuracy and stability of the motor. In particular, when the turntable is required to maintain efficient operation in various operating postures such as upright or inverted, it poses new challenges to the control algorithm and feedback mechanism design of the motor. Previous feedback systems mostly rely on a single technology, such as the common photoelectric encoder, which can provide position feedback, but may have problems of accuracy loss or insufficient reliability under certain extreme working conditions. Summary of the invention

[0005] One of the purposes of the present invention is to provide an objective lens converter, aiming to improve the stability of a microscope system so that the objective lens converter can maintain consistent performance regardless of different working postures such as upright or inverted.

[0006] The technical solution adopted by the present invention to achieve the above-mentioned purpose is as follows:

[0007] An objective lens converter comprises a turntable for mounting an objective lens, wherein the upper surface of the turntable is provided with an annular upper groove for placing a ball, the lower surface of the turntable is provided with an annular lower groove for placing a ball, the turntable is provided with an initial position mark, and further comprises:

[0008] An upper cover installed above the rotating disk, the upper cover having an annular cover plate groove and an inner annular rib, the inner annular rib corresponding to the annular upper groove of the rotating disk is used to limit the ball placed in the annular upper groove;

[0009] a stepper motor, the output shaft of the stepper motor being directly coupled to the center of the turntable;

[0010] A base, wherein a mounting hole for mounting the stepping motor is provided at the middle position of the lower part of the base, and an annular guide rail is provided on the upper surface of the base, and the annular guide rail and the annular lower groove of the turntable are provided correspondingly to limit the position of the ball placed in the annular lower groove;

[0011] A magnetic encoder, mounted on the stepper motor, for monitoring the rotation angle of the stepper motor;

[0012] A first photoelectric switch sensor is installed in the cover plate groove of the upper cover, and is used to monitor the position of the objective lens on the turntable and feed back to the stepping motor and the magnetic encoder;

[0013] The second photoelectric switch sensor is installed in the cover plate groove of the upper cover, and is used to monitor the initial position mark of the turntable and feed back to the stepping motor and the magnetic encoder.

[0014] The present invention uses a stepper motor to directly drive the turntable to rotate. The energy consumption management of the stepper motor itself under precise control is more efficient. Compared with the indirect drive, the design structure is simplified, the mechanical wear is less, the maintenance cycle is reduced, and the cost is reduced. In addition, the present invention is designed with a unique support structure for the turntable. Ball bearings are installed on the upper and lower surfaces of the turntable to maintain the posture of the turntable. Whether the turntable is operated in an upright or inverted state, it can be guaranteed to be stable and reliable, ensuring the effective transmission and balance of the motor driving force, avoiding the additional load or stress concentration that may be generated under different postures, thereby maintaining the consistency of system performance.

[0015] The present invention also has the following preferred design:

[0016] The first photoelectric switch sensor of the present invention is installed in the cover plate groove of the upper cover through the first bracket to protect the first photoelectric switch sensor and ensure its stability.

[0017] The second photoelectric switch sensor of the present invention is installed in the cover plate groove of the upper cover through the second bracket to protect the second photoelectric switch sensor and ensure its stability.

[0018] The lower surface of the inner annular rib of the upper cover of the present invention is provided with an annular upper cover plate ball groove, so that the movement process of the balls installed on the upper surface of the turntable is more stable, thereby ensuring the stability of the turntable rotation.

[0019] The upper surface of the annular guide rail of the present invention is provided with an annular ball track groove, so that the movement process of the balls installed on the lower surface of the turntable is more stable, thereby ensuring the stability of the rotation of the turntable.

[0020] The magnetic encoder of the present invention is a thin magnetic angle encoder.

[0021] The stepper motor of the present invention is a 42 stepper motor using a TMC2590 driver chip. The driver chip decomposes the rotation of the stepper motor into 256 subdivisions. Through 256 pulse signals, the stepper motor is rotated by a step angle of 1.8°. The motor rotates one circle from the original 200 pulses to 51200 pulses, making the rotation of the motor more precise and the start and stop of the motor more stable.

[0022] A second object of the present invention is to provide a rotation positioning method for the above-mentioned objective lens converter, comprising the steps of:

[0023] After the device is powered on, it sends a unique device number to the host computer via the serial port, and the second photoelectric switch sensor detects the initial position mark of the turntable.

[0024] If the initial position flag of the turntable is detected, enter the main program;

[0025] If the initial position mark of the turntable is not detected, the stepper motor is started and rotated with a single pulse step until the initial position mark is detected and then the main program is entered;

[0026] After entering the main program, the serial port sends the rotation instruction corresponding to the turntable rotating to the target position, calculates the angle that needs to be rotated, sends the required number of pulses to the stepper motor, and the magnetic encoder monitors the rotation angle of the stepper motor. When the stepper motor finishes rotating, the first photoelectric switch sensor detects whether the objective lens has rotated to the target position. If it has not rotated into place, the stepper motor rotates with a single pulse step to find the target position of the objective lens. After the first photoelectric switch sensor detects the target position of the objective lens, the serial port sends the current position to the main program. At this point, one rotation of the objective lens is completed, and the main program stands by, waiting for the next rotation instruction.

[0027] Preferably, the serial port sends the rotation instruction corresponding to the turntable rotating to the target position, calculates the required rotation angle, sends the required number of pulses to the stepper motor, and then the stepper motor performs S-shaped acceleration and deceleration motion. The motion stages are divided into: acceleration stage, deceleration stage, uniform speed stage, acceleration and deceleration stage, and deceleration stage.

[0028] The present invention uses a magnetic encoder and a photoelectric switch to form a composite feedback system. The thin magnetic encoder uses high precision and strong anti-interference ability to ensure accurate monitoring of the objective lens position under various operating conditions, while the photoelectric switch provides auxiliary positioning at key positions to enhance the robustness of the system. This composite feedback design ensures rapid response and positioning accuracy of the objective lens conversion, which is the key to improving the overall system performance.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The present invention optimizes the support structure of the turntable so that the electric objective turntable can maintain consistent performance regardless of different working modes such as upright or inverted, thereby improving the versatility and adaptability of the system. Users do not need to worry about the impact of changes in the device posture on the objective lens conversion performance, broadening the application scope of the device in a variety of experimental environments and configurations, and increasing the flexibility and convenience of use.

[0031] 2. The magnetic encoder of the present invention provides continuous and accurate position feedback, and the photoelectric switch realizes hard stop and precise positioning at key positions. The combination of the two forms a complementary feedback network, which can realize high-precision position monitoring and instant adjustment, ensure the positioning error of objective lens switching is minimized, improve the robustness and intelligent adjustment ability of the system to cope with complex working conditions, and enhance the self-diagnosis and adaptability of the system to abnormal situations. The microscope system using the present invention can automatically adapt to different working conditions, adjust the driving strategy in time, effectively prevent positioning errors caused by erroneous operation or external interference, and improve the user experience and the intelligence of the system. The present invention can significantly reduce the image loss or distortion caused by objective lens switching delay in application scenarios that require rapid and continuous switching of objective lenses, such as real-time cell imaging and FRET experiments, and ensure the continuity and reliability of experimental data.

[0032] 3. The present invention adopts direct drive mode to reduce the energy consumption of traditional transmission devices, reduce heat generation, and improve overall energy efficiency. At the same time, it simplifies the mechanical structure and reduces component wear. The present invention is more energy-saving and environmentally friendly, with lower operating costs and longer service life, bringing users a more economical and sustainable use experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A stereoscopic diagram of an objective lens converter according to the present invention;

[0034] Figure 2 for Figure 1 A schematic diagram of the half-section structure of the objective lens converter;

[0035] Figure 3 for Figure 1 Exploded view of the central nosepiece;

[0036] Figure 4 for Figure 1 The internal structure of the objective lens converter, with the upper cover and base removed;

[0037] Figure 5 yes Figure 4 A front view of

[0038] Figure 6 yes Figure 5 Schematic diagram of the half section after removing the objective lens;

[0039] Figure 7 yes Figure 1 The structure diagram of the objective lens converter after removing the upper cover;

[0040] Figure 8 yes Figure 1 The structure diagram of the objective lens converter after removing the base;

[0041] Fig. 9 is a control flow chart of the objective lens converter rotation positioning method of the present invention;

[0042] Fig.10 It is a principle diagram of the stepping motor of the present invention performing S-shaped acceleration and deceleration motion.

[0043] Description of reference numerals:

[0044] 1. Turntable; 1a. Upper annular groove; 1b. Lower annular groove; 2. Objective lens; 3. Upper cover; 3a. Cover plate groove; 3b. Inner annular rib; 4. Stepper motor; 5. Base; 5a. Mounting hole; 5b. Annular guide rail; 6. Magnetic encoder; 7. Ball bearing; 8. First photoelectric switch sensor; 8a. First bracket; 9. Second photoelectric switch sensor; 9b. Second bracket. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical scheme and advantages of the present invention more obvious, the exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments of the present invention, and it should be understood that the present invention is not limited to the exemplary embodiments described herein. Based on the embodiments of the present invention described in the present invention, all other embodiments obtained by those skilled in the art without creative work should fall within the protection scope of the present invention.

[0046] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present invention. However, it is apparent to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features well known in the art are not described.

[0047] It should be understood that the present invention can be implemented in different forms and should not be interpreted as limited to the embodiments set forth herein. On the contrary, these embodiments are provided to make the disclosure thorough and complete and to fully convey the scope of the present invention to those skilled in the art.

[0048] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present invention. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0049] In order to fully understand the present invention, a detailed structure will be proposed in the following description to illustrate the technical solution proposed by the present invention. The optional embodiments of the present invention are described in detail as follows, but in addition to these detailed descriptions, the present invention may also have other implementations.

[0050] like Figures 1 to 8 As shown, an objective lens converter includes a turntable 1 for mounting an objective lens 2, an upper surface of the turntable 1 is provided with an annular upper groove 1a for placing a ball 7, a lower surface of the turntable 1 is provided with an annular lower groove 1b for placing the ball 7, the turntable 1 is provided with an initial position mark, and further includes:

[0051] An upper cover 3 is installed above the turntable 1, and the upper cover 3 has an annular cover groove 3a and an inner annular rib 3b. The inner annular rib 3b is arranged corresponding to the annular upper groove 1a of the turntable 1 to limit the ball 7 placed in the annular upper groove 1a;

[0052] The stepper motor 4, the output shaft of the stepper motor 4 is directly coupled to the center of the turntable 1, specifically, the output shaft of the stepper motor 4 passes through the base 5 and is fixedly connected to the center hole of the turntable 1;

[0053] A base 5, a mounting hole 5a for mounting the stepping motor 4 is provided at the middle position of the lower part of the base 5, an annular guide rail 5b is provided on the upper surface of the base 5, and the annular guide rail 5b is provided corresponding to the annular lower groove 1b of the turntable 1 for limiting the ball 7 placed in the annular lower groove 1b;

[0054] A magnetic encoder 6 is mounted on the stepper motor 4 and is used to monitor and control the rotation angle of the stepper motor 4;

[0055] The first photoelectric switch sensor 8 is installed in the cover plate groove 3a of the upper cover 3, and is used to monitor the position of the objective lens 2 on the turntable 1 and feed back to the stepping motor 4 and the magnetic encoder 6;

[0056] The second photoelectric switch sensor 9 is installed in the cover plate groove 3 a of the upper cover 3 , and is used to monitor the initial position mark of the turntable 1 and feed back to the stepping motor 4 and the magnetic encoder 6 .

[0057] In one embodiment, the first photoelectric switch sensor 8 is installed in the cover plate groove 3a of the upper cover 3 through the first bracket 8a to protect the first photoelectric switch sensor 8 and ensure its stability.

[0058] In one embodiment, the second photoelectric switch sensor 9 is installed in the cover plate groove 3a of the upper cover 3 through the second bracket 9a to protect the second photoelectric switch sensor 9 and ensure its stability.

[0059] In one embodiment, an annular upper cover plate ball groove is provided on the lower surface of the inner annular rib 3b of the upper cover 3, so that the movement process of the balls 7 installed on the upper surface of the turntable 1 is more stable, thereby ensuring the stability of the rotation of the turntable 1.

[0060] In one embodiment, an annular ball track groove is provided on the upper surface of the annular guide rail 5 b, so that the movement of the balls 7 installed on the lower surface of the turntable 1 is more stable, thereby ensuring the stability of the rotation of the turntable 1 .

[0061] In one embodiment, the magnetic encoder 6 is a thin magnetic angle encoder.

[0062] In one embodiment, the stepper motor 4 is a 42 stepper motor using a TMC2590 driver chip. The driver chip decomposes the rotation of the stepper motor into 256 subdivisions. Through 256 pulse signals, the stepper motor 4 rotates a step angle of 1.8°. The motor rotates one circle from the original 200 pulses to 51200 pulses, making the rotation of the motor more precise and the start and stop of the motor smoother.

[0063] In one embodiment, the ball may be a solid 304 stainless steel ball with a diameter of 5 mm.

[0064] like Fig. 9As shown, the rotation positioning method of the above-mentioned objective lens converter includes the steps of:

[0065] After the device is powered on, it sends a unique device number to the upper computer via the serial port to confirm the controlled device. The second photoelectric switch sensor 9 detects the initial position mark of the turntable 1.

[0066] If the initial position flag of the turntable is detected, enter the main program;

[0067] If the initial position mark of the turntable 1 is not detected, the stepper motor 4 is started and rotated with a single pulse step until the initial position mark is detected and then the main program is entered;

[0068] After entering the main program, the serial port sends the rotation instruction corresponding to the turntable 1 rotating to the target position, calculates the angle to be rotated, sends the required number of pulses to the stepper motor 4, and the magnetic encoder 6 monitors the rotation angle of the stepper motor. When the stepper motor 4 finishes rotating, the first photoelectric switch sensor 8 detects whether the objective lens has rotated to the target position. If it has not rotated into place, the stepper motor 4 rotates with a single pulse step to find the target position of the objective lens 2. After the first photoelectric switch sensor 8 detects the target position of the objective lens, the serial port sends the current position to the main program. At this point, one rotation of the objective lens 2 is completed, and the main program stands by, waiting for the next rotation instruction.

[0069] like Fig.10 As shown, the serial port sends the rotation instruction corresponding to the turntable 2 rotating to the target position, calculates the required rotation angle, sends the required number of pulses to the stepper motor 4, and the stepper motor 4 performs S-shaped acceleration and deceleration motion. The motion stages are divided into: acceleration stage, deceleration stage, uniform speed stage, acceleration and deceleration stage, and deceleration stage.

[0070] Through technological innovation, this application has achieved significant progress compared with the existing technology in terms of improving the response speed, positioning accuracy, system stability, energy efficiency and intelligence level of the electrically-controlled objective lens converter, bringing revolutionary improvements to the objective lens conversion technology of microscopes and other precision optical instruments.

[0071] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. An objective lens converter, comprising a turntable (1) for mounting an objective lens (2), characterized in that: The upper surface of the rotating disk (1) is provided with an annular upper groove (1a) for placing the ball (7), the lower surface of the rotating disk (1) is provided with an annular lower groove (1b) for placing the ball (7), the rotating disk (1) is provided with an initial position mark, and further comprises: An upper cover (3) mounted above the rotating disk (1), the upper cover (3) having an annular cover plate groove (3a) and an inner annular retaining edge (3b), the inner annular retaining edge (3b) being arranged corresponding to the annular upper groove (1a) of the rotating disk (1) and used for limiting the position of a ball (7) placed in the annular upper groove (1a); A stepper motor (4), the output shaft of the stepper motor (4) being directly coupled to the center of the turntable (1); A base (5), wherein a mounting hole (5a) for mounting the stepping motor (4) is provided at a middle position of a lower portion of the base (5), an annular guide rail (5b) is provided on an upper surface of the base (5), and the annular guide rail (5b) is provided corresponding to an annular lower groove (1b) of the turntable (1) for limiting a ball (7) placed in the annular lower groove (1b); A magnetic encoder (6) mounted on the stepper motor (4) for monitoring the rotation angle of the stepper motor (4); A first photoelectric switch sensor (8) is installed in the cover plate groove (3a) of the upper cover (3) and is used to monitor the position of the objective lens (2) on the turntable (1) and feed back to the stepping motor (4) and the magnetic encoder (6); A second photoelectric switch sensor (9) is installed in the cover plate groove (3a) of the upper cover (3) and is used to monitor the initial position mark of the turntable (1) and feed back to the stepping motor (4) and the magnetic encoder (6).

2. The objective lens converter according to claim 1, characterized in that: The first photoelectric switch sensor (8) is installed in the cover plate groove (3a) of the upper cover (3) via a first bracket (8a).

3. The objective lens converter according to claim 1, characterized in that: The second photoelectric switch sensor (9) is installed in the cover plate groove (3a) of the upper cover (3) via a second bracket (9a).

4. The objective lens converter according to claim 1, characterized in that: The lower surface of the inner annular rib (3b) of the upper cover (3) is provided with an annular upper cover plate ball groove.

5. The objective lens converter according to claim 1, characterized in that: An annular ball track groove is provided on the upper surface of the annular guide rail (5b).

6. The objective lens converter according to claim 1, characterized in that: The magnetic encoder (6) is a thin magnetic angle encoder.

7. The objective lens converter according to claim 1, characterized in that: The stepper motor (4) is a 42 stepper motor using a TMC2590 drive chip. 256 pulse signals are used to allow the stepper motor (4) to rotate by a step angle, and the step angle is 1.8°.

8. A rotation positioning method for an objective lens converter according to any one of claims 1 to 7, characterized in that: Includes steps: After the device is powered on, it sends a unique device number to the upper computer via the serial port, and the second photoelectric switch sensor (9) detects the initial position mark of the turntable (1). If the initial position flag of the turntable (1) is detected, the main program is entered; If the initial position mark of the turntable (1) is not detected, the stepper motor (4) is started and rotated with a single pulse step until the initial position mark is detected and then the main program is entered; After entering the main program, the serial port sends a rotation instruction corresponding to the rotation of the turntable (1) to the target position, calculates the angle to be rotated, sends the required number of pulses to the stepper motor (4), and the magnetic encoder (6) monitors the rotation angle of the stepper motor (4). When the stepper motor (4) finishes rotating, the first photoelectric switch sensor (8) detects whether the objective lens (2) has rotated to the target position. If it has not rotated to the target position, the stepper motor (4) rotates with a step length of a single pulse to find the target position of the objective lens (2). After the first photoelectric switch sensor (8) detects the target position of the objective lens (2), the serial port sends the current position to the main program. At this point, one rotation of the objective lens (2) is completed, and the main program stands by and waits for the next rotation instruction.

9. The rotation positioning method of the objective lens converter according to claim 8, characterized in that: The serial port sends a rotation instruction corresponding to the rotation of the turntable (1) to the target position, calculates the required rotation angle, and sends the required number of pulses to the stepper motor (4). The stepper motor then performs an S-shaped acceleration and deceleration motion. The motion stages are divided into: acceleration stage, deceleration stage, uniform speed stage, acceleration and deceleration stage, and deceleration and deceleration stage.

Images