Automatic focusing module

Abstract

The utility model relates to an automatic focusing module. The automatic focusing module comprises a carrier plate; a motor is further included; the prism unit comprises a first wedge-shaped prism and a second wedge-shaped prism, and the second wedge-shaped prism is driven by the rotor to move in the extending direction of the second inclined plane; the lens unit is arranged towards the prism unit, and the prism unit is located between the lens unit and the workpiece to be machined; the device further comprises a control unit and a sensor unit, the sensor unit is used for monitoring deformation data of the workpiece to be machined and uploading the deformation data to the control unit, and the control unit controls the driving unit to adjust the thickness of the prism unit so as to adjust the focal length of the lens unit. When the automatic focusing module is used, the automatic focusing module is placed between a lens and a workpiece to be machined, the focal surface shape variable of the workpiece to be machined is detected in combination with the displacement sensor, the working focal length of the lens unit is automatically adjusted through the control unit, the accuracy of automatic focusing can be effectively improved, and then the imaging quality of the lens unit can be effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of optics, in particular to an automatic focusing module. Background Art

[0002] When the optical system is defocused due to various reasons (such as temperature changes, zooming process, deformation of workpieces, etc.), the system needs to be compensated for defocus. Especially in some high-precision PCB exposure, laser welding, laser engraving and other fields, in order to obtain finer line widths, the focal depth of the lens imaging is further reduced, and the problem of the focal plane working distance of the lens will be more prominent. Therefore, it is necessary to compensate for the imaging system. In the prior art, the wedge prism group of the automatic focusing module is mostly an independent fixed structure and a motion slide rail system. When assembled with the motor module, since the motor itself has a motion slide rail system, in order to ensure the accuracy of the prism group during operation, the two sets of running slide rail systems need to be adjusted together.

[0003] However, the shortcomings of the prior art are that since the two slide rail systems need to be debugged and made to have a high degree of fit, the difficulty of assembly and adjustment is increased, more time is required for progress adjustment, and the accuracy stability is poor, resulting in a decrease in the accuracy of automatic focusing. Utility Model Content

[0004] To this end, the technical problem to be solved by the utility model is to overcome the deficiencies in the prior art and provide an automatic focusing module that can achieve high-precision adjustment of the lens working distance. The wedge-shaped prism group and the motor used to adjust the focal length are integrated into the module, so that the module has a compact structure, small size, and light weight, and is more adaptable to small areas in space. It can be used in a wider range of scenarios and can effectively improve the accuracy of automatic focusing.

[0005] In order to solve the above technical problems, the utility model provides an automatic focusing module, comprising:

[0006] Carrier board;

[0007] A driving unit, comprising a motor, the motor being arranged on the carrier plate, the motor comprising a stator and a mover;

[0008] A prism unit, comprising a first wedge-shaped prism and a second wedge-shaped prism, wherein the first wedge-shaped prism is disposed on the mover, and the second wedge-shaped prism is disposed on the stator, the first wedge-shaped prism has a first inclined surface, and the second wedge-shaped prism has a second inclined surface, the first inclined surface is opposite to the second inclined surface, and the first inclined surface and the second inclined surface are parallel to each other, and the first wedge-shaped prism moves synchronously under the drive of the mover;

[0009] A lens unit, which is arranged toward the prism unit, and the prism unit is located between the lens unit and the workpiece to be processed;

[0010] A control unit, which is electrically connected to the driven unit and the lens unit;

[0011] A sensor unit is arranged on the carrier plate, and is used to monitor the deformation data of the workpiece to be processed and upload the deformation data to the control unit. The control unit controls the driving unit to adjust the thickness of the prism unit to adjust the focal length of the lens unit.

[0012] In one embodiment of the utility model, the driving unit further includes a slide rail assembly, the slide rail assembly includes a first slide rail and a second slide rail, the first slide rail is arranged on the mover, the second slide rail is arranged and connected to the stator, and the first slide rail and the second slide rail are slidably connected.

[0013] In one embodiment of the present invention, the motor is a voice coil motor.

[0014] In an embodiment of the utility model, a support seat is further provided on the carrier plate, and the support seat is used to support the driving unit, and the plane where the support surface of the support seat is located is parallel to the first inclined surface.

[0015] In an embodiment of the present invention, a through hole is provided on the carrier plate, a projection area of ​​the through hole along the height direction is not less than a projection area of ​​the prism unit along the height direction, and the through hole is located below the prism unit.

[0016] In one embodiment of the present invention, the sensor unit includes a first sensor and a second sensor, and the first sensor and the second sensor are arranged at the bottom of the carrier board.

[0017] In one embodiment of the present invention, the first sensor and the second sensor are at an equal distance from the workpiece to be processed.

[0018] In one embodiment of the present invention, the sensor unit further includes a first bracket and a second bracket, the first bracket and the second bracket are arranged on the carrier, the first sensor is mounted on the carrier via the first bracket, and the second sensor is mounted on the carrier via the second bracket.

[0019] In one embodiment of the present invention, the first sensor and the second sensor are laser displacement sensors.

[0020] In an embodiment of the present invention, the projection of the prism unit along the height direction is not less than the projection of the workpiece to be processed along the height direction.

[0021] The above technical solution of the utility model has the following advantages compared with the prior art:

[0022] The utility model discloses an automatic focusing module, which is provided with a carrier, a driving unit, a prism unit, a lens unit, a control unit and a sensor unit, wherein the prism unit is connected to the driving unit, and the prism unit is arranged between the lens unit and the workpiece to be processed, and cooperates with the sensor unit to detect the deformation data of the focal plane of the workpiece to be processed, and after the control unit obtains the deformation data, it controls the driving unit to adjust the thickness of the prism unit, thereby realizing the focal length adjustment of the lens unit. The utility model can realize the high-precision adjustment of the working focal length of the lens, by integrating the wedge prism unit used to adjust the focal length with the motor, and because the prism unit is arranged in the area between the slide rail components and realizes the integrated design with the motor, the prism unit and the motor can share the same set of slide rail components, and can realize the relative movement of the first wedge prism and the second wedge prism based on the same slide rail component. Compared with the prior art, while improving the accuracy, the overall volume of the module is effectively reduced, the installation space is saved, and the entire module structure is compact, small in volume, light in weight, and more adaptable to the narrow space area, thereby making the application scene of the utility model more extensive. Furthermore, by placing the automatic focusing module between the lens and the workpiece, the focal plane deformation of the workpiece to be processed is detected in combination with a displacement sensor and uploaded to the control unit, the working focal length of the lens unit can be automatically adjusted through the control unit, and the accuracy of automatic focusing can be effectively improved, thereby effectively improving the imaging quality of the lens unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to make the content of the utility model easier to understand, the utility model is further described in detail according to the specific embodiments of the utility model in combination with the accompanying drawings, wherein:

[0024] Figure 1 It is a front view of the partial structure of the driving unit, the prism unit and the carrier plate of the preferred embodiment of the utility model.

[0025] Figure 2 yes Figure 1 A schematic diagram of the cross-sectional structure from the first perspective.

[0026] Figure 3 yes Figure 1 A schematic diagram of the cross-sectional structure from a second viewing angle.

[0027] Figure 4 It is a three-dimensional schematic diagram of the overall structure of a preferred embodiment of the utility model.

[0028] Figure 5 It is a front view of the overall structure of a preferred embodiment of the utility model.

[0029] Figure 6 yes Figure 4 Schematic diagram of the cross-sectional structure.

[0030] Figure 7 It is a schematic diagram of a focusing device in the prior art.

[0031] Explanation of the reference numerals in the drawings in the specification: 1. carrier plate; 10. support seat; 2. motor; 20. stator; 200. second slide rail; 21. mover; 210. first slide rail; 31. first wedge-shaped prism; 32. second wedge-shaped prism; 4. lens unit; 5. workpiece to be processed; 61. first sensor; 62. second sensor; 71. first bracket; 72. second bracket. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0033] Embodiment 1

[0034] Reference Figures 1 to 7 As shown, the utility model discloses an automatic focusing module, comprising a carrier plate 1, wherein the carrier plate 1 plays a supporting role;

[0035] The automatic focusing module further includes a driving unit, which is disposed on the carrier 1 and located on the upper surface of the carrier 1. The driving unit includes a motor 2, and the motor 2 has a stator 20 and a mover 21;

[0036] The automatic focusing module further comprises a prism unit, and the prism unit comprises a first wedge-shaped prism 31 and a second wedge-shaped prism 32, wherein the first wedge-shaped prism 31 is arranged on the mover 21, and the second wedge-shaped prism 32 is arranged on the stator 20. The first wedge-shaped prism 31 and the second wedge-shaped prism 32 are arranged up and down.

[0037] In terms of details, the first wedge-shaped prism 31 has a first inclined surface, the second wedge-shaped prism has a second inclined surface, the first inclined surface is opposite to the second inclined surface, and the first inclined surface and the second inclined surface are parallel to each other. When the motor is started, the first wedge-shaped prism 31 can move along the extension direction of the first inclined surface driven by the mover 21.

[0038] It should be noted that when the first wedge-shaped prism 31 moves toward the downhill direction of the first inclined surface, the thickness of the first wedge-shaped prism 31 and the second wedge-shaped prism 32 along the optical axis direction will gradually decrease. On the contrary, when the first wedge-shaped prism 31 moves toward the uphill direction of the first inclined surface, the thickness of the first wedge-shaped prism 31 and the second wedge-shaped prism 32 along the optical axis direction will gradually increase. In this way, the focal length of the light beam irradiated to the prism unit will change.

[0039] The automatic focusing module further includes a lens unit 4, which is disposed toward the prism unit, and the prism unit is located between the lens unit 4 and a workpiece 5 to be processed, and the workpiece 5 to be processed is disposed on the side where the lower surface of the carrier 1 is located. The prism unit for focusing is disposed below the lens unit, so that the pattern light can be transmitted to the prism unit. Therefore, when the thickness of the prism unit along the optical axis direction changes, the focal length of the lens unit will also change accordingly.

[0040] The automatic focusing module also includes a control unit, which is electrically connected to the driving unit and the lens unit.

[0041] The automatic focusing module also includes a sensor unit, which is arranged on the carrier plate 1. The sensor unit is used to monitor the deformation data of the workpiece to be processed and upload the deformation data to the control unit. The control unit controls the driving unit to adjust the thickness of the prism unit, thereby realizing the adjustment of the focal length of the lens unit.

[0042] Specifically, the driving unit further includes a slide rail assembly, which includes a first slide rail 210 and a second slide rail 200, wherein the first slide rail 210 is disposed on the mover 21, and the second slide rail 200 is disposed on the stator 20 and connected thereto, and the first slide rail 210 and the second slide rail 200 are slidably connected. Such an arrangement effectively improves the accuracy of the stator 20 and the mover 21 during operation.

[0043] Furthermore, since the prism unit is disposed in the area between the rail assemblies and is integrated with the motor 2, the prism unit and the motor 2 can share the same rail assembly, and the relative movement of the first wedge-shaped prism 31 and the second wedge-shaped prism 32 can be achieved based on the same rail assembly. Compared with the prior art, the overall volume of the module is effectively reduced while the accuracy is improved, saving installation space.

[0044] It can be known that the automatic focusing module to be protected by the utility model is provided with a carrier, a driving unit, a prism unit, a lens unit, a control unit and a sensor unit, wherein the prism unit is connected to the driving unit, and the prism unit is arranged between the lens unit and the workpiece to be processed, and cooperates with the sensor unit to detect the deformation data of the focal plane of the workpiece to be processed. After the control unit obtains the deformation data, it controls the driving unit to adjust the thickness of the prism unit, thereby realizing the focal length adjustment of the lens unit. The utility model can realize the high-precision adjustment of the working focal length of the lens, and by integrating the wedge-shaped prism unit used to adjust the focal length with the motor, the whole module structure is compact, small in size, light in weight, and more adaptable to small space areas, thereby making the application scenarios of the utility model more extensive. In addition, by placing the automatic focusing module between the lens and the workpiece, combining the displacement sensor to detect the focal plane deformation of the workpiece to be processed, and uploading it to the control unit, the working focal length of the lens unit can be automatically adjusted by the control unit, and the accuracy of automatic focusing can be effectively improved, thereby effectively improving the imaging quality of the lens unit.

[0045] As a preferred embodiment, the motor 2 adopts a voice coil motor. It should be explained that the voice coil motor is a direct drive motor. It has the characteristics of simple structure, small size, high speed, high acceleration and fast response. Its working principle is that when a powered coil (conductor) is placed in a magnetic field, a force will be generated, and the magnitude of the force is proportional to the current applied to the coil. The voice coil motor manufactured based on this principle can move in a straight line or arc.

[0046] As a preferred embodiment, in order to ensure that the first wedge-shaped prism 31 and the second wedge-shaped prism 32 remain stable during relative movement, the first wedge-shaped prism 31 is assembled to the mover by dispensing glue, and similarly, the second wedge-shaped prism 32 is assembled to the stator by dispensing glue.

[0047] As a preferred implementation, in order to facilitate the assembly of the prism unit to the motor 2 , the first wedge-shaped prism 31 and the second wedge-shaped prism 32 have the same size.

[0048] Furthermore, a support seat 10 is further provided on the carrier 1, and the support seat 10 is used to carry the driving unit, and the plane where the bearing surface of the support seat 10 is located is parallel to the first inclined surface. Therefore, when the motor 2 is assembled on the carrier 1, it can be conveniently installed in conjunction with the first wedge-shaped prism 31 and the second wedge-shaped prism 32, and the prism unit formed by the first wedge-shaped prism 31 and the second wedge-shaped prism 32 is in a horizontal direction as a whole, and the top surface and the bottom surface of the prism unit are parallel to the horizontal direction.

[0049] In detail, a through hole is provided on the carrier 1, and the projection area of ​​the through hole along the height direction is not less than the projection area of ​​the prism unit along the height direction, and the through hole is located below the prism unit. Such a configuration enables the pattern light to be transmitted to the prism unit, so that an optical circuit can be formed between the lens unit, the prism unit and the workpiece to be processed.

[0050] Furthermore, the sensor unit includes a first sensor 61 and a second sensor 62, and the first sensor 61 and the second sensor 62 are respectively arranged at the bottom of the carrier plate 1, and in order to ensure that the first sensor 61 and the second sensor 62 can monitor the deformation data based on the same reference position, the transmitting end of the first sensor 61 and the transmitting end of the second sensor 62 are at the same distance from the workpiece to be processed.

[0051] As a preferred embodiment, the sensor unit further includes a first bracket 71 and a second bracket 72, and the first bracket 71 and the second bracket 72 are arranged at the bottom of the carrier 1. The first sensor 61 is mounted on the first bracket 71 by bolts, so that the first sensor 61 is arranged on the carrier 1 through the first bracket 71. The second sensor 62 is mounted on the second bracket 72 by bolts, so that the second sensor 62 is arranged on the carrier 1 through the second bracket 72.

[0052] As a preferred embodiment, the first sensor 61 and the second sensor 62 are both laser displacement sensors. In detail, the laser displacement sensor includes but is not limited to a point laser displacement sensor or a line laser displacement sensor.

[0053] As a preferred implementation, in order to make the coverage area of ​​the prism unit more comprehensive, the projection of the prism unit along the height direction is not less than the projection of the workpiece to be processed along the height direction.

[0054] Specifically, the installation steps of the automatic focusing module are as follows:

[0055] Step 1: Assemble the prism unit and the motor by using an assembly jig, wherein the first wedge-shaped prism is fixed on the motor mover, and the second wedge-shaped prism is fixed on the motor stator. The distance between the two prism gaps and the upper surface of the motor is measured and adjusted to within the tolerance range by using the assembly jig, and the prism is fixed to the motor by dispensing glue;

[0056] Step 2: Install the motor onto the carrier board and secure it with screws;

[0057] Step three: assemble the point or line laser displacement sensor on the bottom of the carrier board to complete the assembly.

[0058] Embodiment 2

[0059] The utility model also discloses a laser engraving device, comprising an engraving unit and an automatic focusing module as described in the first embodiment. The automatic focusing module can be used to automatically adjust the focal length of the laser engraving device.

[0060] In the description of the embodiments of the present utility model, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0061] In the description of the present utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0062] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0063] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention of the utility model.

Claims

1. An automatic focusing module, characterized in that: include, Carrier board; A driving unit, comprising a motor, the motor being arranged on the carrier plate, the motor comprising a stator and a mover; A prism unit, comprising a first wedge-shaped prism and a second wedge-shaped prism, wherein the first wedge-shaped prism is disposed on the mover, and the second wedge-shaped prism is disposed on the stator, the first wedge-shaped prism has a first inclined surface, and the second wedge-shaped prism has a second inclined surface, the first inclined surface is opposite to the second inclined surface, and the first inclined surface and the second inclined surface are parallel to each other, and the first wedge-shaped prism moves synchronously under the drive of the mover; A lens unit, which is arranged toward the prism unit, and the prism unit is located between the lens unit and the workpiece to be processed; A control unit, which is electrically connected to the driven unit and the lens unit; A sensor unit is arranged on the carrier plate, and is used to monitor the deformation data of the workpiece to be processed and upload the deformation data to the control unit. The control unit controls the driving unit to adjust the thickness of the prism unit to adjust the focal length of the lens unit.

2. The automatic focusing module according to claim 1, characterized in that: The driving unit further includes a slide rail assembly, which includes a first slide rail and a second slide rail. The first slide rail is disposed on the mover, and the second slide rail is disposed and connected to the stator. The first slide rail and the second slide rail are slidably connected.

3. The automatic focusing module according to claim 1, characterized in that: The motor is a voice coil motor.

4. The automatic focusing module according to claim 1, characterized in that: The carrier plate is further provided with a support seat, and the support seat is used to support the driving unit, and the plane where the support surface of the support seat is located is parallel to the first inclined surface.

5. The automatic focusing module according to claim 1, characterized in that: The carrier plate is provided with a through hole, the projection area of ​​the through hole along the height direction is not less than the projection area of ​​the prism unit along the height direction, and the through hole is located below the prism unit.

6. An automatic focusing module according to any one of claims 1 to 5, characterized in that: The sensor unit includes a first sensor and a second sensor, and the first sensor and the second sensor are disposed at the bottom of the carrier board.

7. The automatic focusing module according to claim 6, characterized in that: The first sensor and the second sensor are at equal distances from the workpiece to be processed.

8. The automatic focusing module according to claim 6, characterized in that: The sensor unit further includes a first bracket and a second bracket, wherein the first bracket and the second bracket are disposed on the carrier board, the first sensor is mounted on the carrier board via the first bracket, and the second sensor is mounted on the carrier board via the second bracket.

9. The automatic focusing module according to claim 6, characterized in that: The first sensor and the second sensor are laser displacement sensors.

10. The automatic focusing module according to claim 1, characterized in that: The projection of the prism unit along the height direction is not less than the projection of the workpiece to be processed along the height direction.

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