Optical device and optical apparatus

Abstract

The application provides an optical device and an optical equipment, and belongs to the technical field of optics. The optical device comprises an arc motor, a grating ruler, a grating sensor and a prism. The arc motor comprises a stator and a rotor which are rotationally connected. The grating ruler is connected to the side of the stator which is away from the rotor. The grating sensor is arranged on the side of the grating ruler which is away from the arc motor. The prism is arranged between the grating sensor and the grating ruler, and the prism can refract the light projected through the grating sensor to the side of the grating ruler which is away from the arc motor. The optical device provided by the application can refract the light projected through the grating sensor to the side of the grating ruler which is away from the arc motor by arranging the prism between the grating sensor and the grating ruler, and can adjust the angle of the incident light through the prism to correct the angle of the incident light, so that the position error can be corrected.

Description

Technical Field

[0001] This application relates to the field of optical technology, and in particular to an optical device and optical equipment. Background Technology

[0002] Currently, encoders are mainly used in industrial automation, robotics, CNC machine tools, and medical equipment. Encoders can accurately measure position, speed, or angle information in real time, providing crucial feedback signals to control systems and helping to achieve precise position and motion control. However, with the increasing use of curved motors, the problem of the grating readhead being obliquely focused on the feedback from these motors leads to inaccurate position recognition and deviations in angle and speed. Utility Model Content

[0003] In view of this, the purpose of this application is to overcome the shortcomings of the prior art and provide an optical device and optical equipment.

[0004] This application provides the following technical solution: an optical device, comprising: Arc-shaped motor, comprising a stator and a rotor that are rotatably connected; A grating ruler is connected to the side of the stator opposite to the rotor; A grating sensor is disposed on the side of the grating ruler opposite to the arc-shaped motor; A prism is disposed between the grating sensor and the grating ruler, and the prism is capable of refracting the light projected through the grating sensor onto the side of the grating ruler opposite to the arc-shaped motor.

[0005] In some embodiments, the prism has a first surface facing the grating sensor in a first direction, the first surface convex to the side away from the grating ruler to form an arc surface.

[0006] In some embodiments, the prism has a second surface facing the arcuate motor along a first direction, the second surface being a plane perpendicular to the first direction.

[0007] In some embodiments, the grating ruler is an arc-shaped ruler, and the center of the circle corresponding to the grating ruler, the center of the circle corresponding to the stator, and the center of the circle of the rotor coincide.

[0008] In some embodiments, along the first direction, the center of the circle corresponding to the first surface and the center of the circle corresponding to the grating ruler are on the same straight line.

[0009] In some embodiments, the grating ruler has graduations on the side opposite to the stator.

[0010] In some embodiments, the grating sensor has a grating reading head that faces the grating ruler.

[0011] In some embodiments, the optical device includes a driving device, the output end of which is connected to the prism, and the driving device is used to drive the prism to move along the first direction.

[0012] In some embodiments, the driving device includes a slide rail, a slider, and a drive motor. The slider is slidably disposed on the slide rail along the first direction and connected to the prism. The output end of the drive motor is connected to the slider.

[0013] Secondly, this application provides an optical device, including the aforementioned optical components.

[0014] The embodiments of this application have the following advantages: by placing a prism between the grating sensor and the grating ruler, the prism can refract the light projected through the grating sensor onto the side of the grating ruler away from the arc motor, and adjust the angle of the incident light by the prism to achieve the purpose of correcting the angle of the incident light, thereby achieving the correction of position error.

[0015] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 The diagram shows a schematic structural view of an optical device provided by some embodiments of the present invention.

[0018] Explanation of key component symbols: 100-Arc motor; 110-Stator; 120-Rotor; 200-Grating ruler; 300-Grating sensor; 400-Prism; 410-First surface; 420-Second surface; 310-Grating reading head. Detailed Implementation

[0019] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote 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 and are only used to explain this application, and should not be construed as limiting this application.

[0020] It should be noted that when an element is said to be "fixed" to another element, it can be directly on the other element or there may be an intervening element. When an element is said to be "connected" to another element, it can be directly connected to the other element or there may be an intervening element. Conversely, when an element is said to be "directly" on another element, there is no intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0021] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the template description is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0024] like Figure 1 As shown, some embodiments of this application provide an optical device, mainly used to correct the angle of incident light, thereby achieving the purpose of correcting position errors and improving the accuracy of angle recognition.

[0025] In this embodiment, the optical devices include an arc motor 100, a grating ruler 200, a grating sensor 300, and a prism 400.

[0026] The arc motor 100 includes a stator 110 and a rotor 120 that are rotatably connected, and the structure of the stator 110 and the rotor 120 is arc-shaped or segmented arc-shaped to adapt to the needs of circular motion or limited angle rotation.

[0027] It should be noted that, in this embodiment, the arc motor 100 can be any one of an arc stepper motor, an arc servo motor, an arc linear motor, or a brushless arc motor, and can be specifically set according to the actual situation.

[0028] In addition, the grating ruler 200 is connected to the side of the stator 110 away from the rotor 120. The connection method between the grating ruler 200 and the stator 110 can be any one of threaded connection, bolt connection, snap-fit, adhesive, magnetic connection, interference fit or integral molding, which can be specifically set according to the actual situation.

[0029] It should be noted that the grating ruler 200 is a high-precision linear displacement measuring device, which is usually used in conjunction with the grating reading head 310. The grating ruler 200 is used to detect the position, speed and direction of linear motion.

[0030] The grating ruler 200 operates based on the principles of optical interference and moiré fringes. The grating reading head 310 emits light (LED or laser) to illuminate the grating ruler 200. When the grating ruler 200 moves, the changes in light transmission / reflection between the gratings form alternating bright and dark moiré fringes. The photoelectric sensor detects the changes in the fringes and converts them into sine wave or square wave signals (A / B phase). After electronic subdivision, the signal outputs high-resolution displacement data (such as 0.1μm / pulse).

[0031] The grating sensor 300 is disposed on the side of the grating ruler 200 away from the arc motor 100. There is a gap between the grating sensor 300 and the grating ruler 200. The distance between the grating sensor 300 and the grating ruler 200 can be specifically set according to the actual situation.

[0032] It should be noted that the grating sensor 300 is a high-precision displacement measuring device based on the principle of optical interference. It achieves accurate measurement of position, speed or direction by detecting changes in the scale lines on the grating ruler 200 (or circular grating).

[0033] In this embodiment, the grating sensor 300 detects changes in the scale lines on the grating ruler 200.

[0034] Additionally, it should be noted that the prism 400 is disposed between the grating sensor 300 and the grating ruler 200. The prism 400 can refract the light projected through the grating sensor 300 onto the side of the grating ruler 200 away from the arc motor 100, and adjust the angle of the incident light through the prism 400 to correct the angle of the incident light, thereby correcting the position error.

[0035] like Figure 1As shown, in some embodiments of the application, the prism 400 has a first surface 410 facing the grating sensor 300 along a first direction. The first surface 410 protrudes to the side away from the grating ruler 200 to form an arc surface, so that the light incident on the first surface 410 can be refracted through the first surface 410 and the optical fiber can be focused through the first surface 410 to adjust the distance of the light on the grating ruler 200, thereby improving the accuracy of the recognition position and reducing the deviation of the angle and velocity.

[0036] Additionally, in some embodiments of the application, the prism 400 has a second surface 420 facing the arc motor 100 along a first direction, the second surface 420 being a plane perpendicular to the first direction.

[0037] It is understood that, along the first direction, the first surface 410 and the second surface 420 are located on opposite sides of the prism 400, respectively.

[0038] It is understood that by setting the first surface 410 as an arc surface to focus light through the first surface 410, and by setting the second surface 420 as a plane perpendicular to the first direction to maintain the propagation direction of the light focused by the first surface 410 through the second surface 420, the purpose of correcting the angle of the incident light is achieved.

[0039] like Figure 1 As shown, in some embodiments of the application, the grating ruler 200 is an arc-shaped ruler, and the center of the circle corresponding to the grating ruler 200, the center of the circle corresponding to the stator 110, and the center of the circle of the rotor 120 coincide, that is, the grating ruler 200 and the center of the arc-shaped motor 100 are coaxial, so as to eliminate Abbe error and ensure the consistency of measurement and motion.

[0040] It should be noted that Abbe error refers to the cosine error caused by the offset between the measurement system and the axis of motion.

[0041] In this embodiment, by setting the grating ruler 200 and the arc motor 100 coaxially, the offset distance is zero, thereby completely eliminating the error and ensuring that the measurement directly reflects the real motion.

[0042] like Figure 1 As shown, in some embodiments of the application, along the first direction, the center of the circle corresponding to the first surface 410 and the center of the circle corresponding to the grating ruler 200 are on the same straight line to ensure the accuracy and stability of the process of correcting the angle of the incident light, while improving the quality of position error correction.

[0043] like Figure 1As shown, in some embodiments of the application, the grating ruler 200 has a scale on the side opposite to the stator 110 to achieve high-precision position detection through optical principles, and to generate a quantifiable displacement signal through the modulation of light by the grating lines.

[0044] It should be noted that the scale (grating fringes) of the grating ruler 200, as a periodic optical mark, will generate alternating bright and dark light signals (moiré fringes) due to the difference in transmission / reflection when the beam of the reading head scans the scale.

[0045] Additionally, it is worth noting that for each shift of the grating pitch (etching cycle), the light intensity changes for one complete cycle. The displacement can be calculated by counting the number of signal cycles (e.g., a 1mm shift of a 40μm grating pitch equals 25 pulses).

[0046] like Figure 1 As shown, in some embodiments of the application, the grating sensor 300 has a grating reading head 310 facing the grating ruler 200.

[0047] It should be noted that, in this embodiment, the grating reading head 310 is used for the transmission, reception and conversion of optical signals.

[0048] In this embodiment, a stable light beam (LED / laser) is emitted by the grating reading head 310 to illuminate the scale on the grating ruler 200, and the change in light intensity caused by the movement of the scale line is converted into an electrical signal (sine wave / square wave). Through electronic subdivision and counting, displacement or angle data (incremental / absolute) is output.

[0049] For example, if the outer diameter of the cylindrical motor is R, the center of the grating ruler 200 is O, the reading head is located at a distance D from the center (D>R), and the initial direction of the optical axis makes an angle θ0 with the first direction, when the rotor 120 rotates by an angle α, θ n (α)α+arcsin(Dsinθ0 / R), the oblique projection error Δθ=θ0-θ between the actual incident angle and the normal. n (α), Based on the above actual occurrence principle, the following vertex angle calculation formula is used to correct this error: The formula for calculating the prism apex angle is: β = (arctan R •sin Δθ) / (n•t - R(1 - cos Δθ). Where n is the refractive index of the prism material (N-SF11 is recommended, n = 1.785), and t is the prism thickness (the prism thickness must satisfy t ≥ R(1 - cosΔθ) / sinβ).

[0050] like Figure 1As shown, in some embodiments of the application, the optical device includes a driving device, the output end of which is connected to the prism 400. The driving device is used to drive the prism 400 to move along the first direction, so as to adjust the distance between the prism 400 and the grating ruler 200 through the driving device, thereby correcting the deviation caused by the original straight line to the curved surface, so as to improve the angle recognition accuracy.

[0051] like Figure 1 As shown, in some embodiments of the application, the driving device (not shown in the figure) includes a slide rail, a slider and a drive motor. The slider is slidably disposed on the slide rail along the first direction, that is, the slider can slide on the slide rail along the first direction and connect the slider to the prism 400. The connection method includes any one of snap-fit, adhesive, or bolt connection, which can be specifically set according to the actual situation.

[0052] The output end of the drive motor is connected to the slider, so that the slider is driven to slide along the slide rail through the output end of the drive motor, and the slider drives the prism 400 to move synchronously in the first direction, thereby adjusting the distance between the prism 400 and the grating ruler 200 to correct the deviation caused by the original straight line to the curved surface.

[0053] like Figure 1 As shown, some embodiments of the application provide an optical device including the optical components described in any of the above embodiments.

[0054] It should be noted that the optical device provided in this application has the structure of the optical device described in any of the above embodiments, and the beneficial effects thereof, which will not be elaborated here.

[0055] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limitations; therefore, other examples of exemplary embodiments may have different values.

[0056] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0057] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application.

Claims

1. An optical device, characterized in that, include: Arc-shaped motor, comprising a stator and a rotor that are rotatably connected; A grating ruler is connected to the side of the stator opposite to the rotor; A grating sensor is disposed on the side of the grating ruler opposite to the arc-shaped motor; A prism is disposed between the grating sensor and the grating ruler, and the prism is capable of refracting the light projected through the grating sensor onto the side of the grating ruler opposite to the arc-shaped motor.

2. The optical device according to claim 1, characterized in that, The prism has a first surface facing the grating sensor in a first direction, and the first surface protrudes to the side away from the grating ruler to form an arc surface.

3. The optical device according to claim 2, characterized in that, The prism has a second surface facing the arc-shaped motor along a first direction, and the second surface is a plane perpendicular to the first direction.

4. The optical device according to claim 1, characterized in that, The grating ruler is an arc-shaped ruler, and the center of the circle corresponding to the grating ruler, the center of the circle corresponding to the stator, and the center of the circle of the rotor coincide.

5. The optical device according to claim 2, characterized in that, Along the first direction, the center of the circle corresponding to the first surface and the center of the circle corresponding to the grating ruler are on the same straight line.

6. The optical device according to claim 1, characterized in that, The grating ruler has graduations on the side opposite to the stator.

7. The optical device according to claim 1, characterized in that, The grating sensor has a grating reading head, which faces the grating ruler.

8. The optical device according to claim 2, characterized in that, The optical device includes a driving device, the output end of which is connected to the prism, and the driving device is used to drive the prism to move along the first direction.

9. The optical device according to claim 8, characterized in that, The driving device includes a slide rail, a slider, and a drive motor. The slider is slidably disposed on the slide rail along the first direction and is connected to the prism. The output end of the drive motor is connected to the slider.

10. An optical device, characterized in that, The optical device included in any one of claims 1 to 9.

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