Photoelectric encoder

Abstract

The utility model provides a photoelectric encoder, which relates to the technical field of sensors, and comprises a photocell array and a fixed grating, the fixed grating is pasted on the upper surface of the photocell array, a plurality of windows are arranged on the fixed grating, and the plurality of windows are arranged in one-to-one correspondence with photocell monomers in the photocell array. And a plurality of stripes are etched on each window. According to the photoelectric encoder, the fixed grating is directly pasted on the photocell array, the structure of the photoelectric encoder is simplified, the connection among components is reduced, the reliability and the stability of the photoelectric encoder are improved, the fixed grating is provided with the window corresponding to the photocell monomers in the photocell array, and stripes are etched on the window, so that the photoelectric encoder is more stable and reliable. Compared with the prior art that segmentation is directly carried out on the light receiving chip, the photocell array segmentation method and device improve the feasibility of photocell array segmentation, segmentation is uniform, segmentation precision is high, the photocell array obtains higher decomposition energy, and then the resolution ratio of the photoelectric encoder is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to a photoelectric encoder. Background Art

[0002] Sensors that can realize angular displacement measurement include rotary transformers, photoelectric encoders and inductive sensors. All of the above components can be used to measure the rotation speed, direction and angular displacement of the motor. Among them, the traditional photoelectric encoder usually includes a light-emitting tube, a dynamic grating, and a photosensitive chip PDIC (composed of a multi-segmented photodiode PD and a circuit-integrated Photo IC). The resolution (unit LPI, i.e. Line Per Inch, the number of lines per foot) that can be achieved by the encoder designed by this process depends on the segmentation accuracy and uniformity of the photosensitive diode PD itself. In general, direct segmentation on the photosensitive chip PDIC results in poor segmentation accuracy of the photosensitive diode PD. When the resolution of the photosensitive diode PD reaches more than 400LPI, the chip yield rate decreases exponentially, which in turn affects the yield rate of the photoelectric encoder and the reliability of the photoelectric encoder itself. Utility Model Content

[0003] In view of the shortcomings of the above-mentioned prior art, the utility model provides a photoelectric encoder, which solves the technical problem that the photoelectric encoder in the prior art usually performs segmentation directly on the light receiving chip, has poor segmentation accuracy and low decomposition energy, and affects the yield and reliability of the photoelectric encoder.

[0004] The utility model provides a photoelectric encoder, comprising a photocell array and a fixed grating; the fixed grating is pasted on the upper surface of the photocell array, a plurality of windows are opened on the fixed grating, the plurality of windows are arranged in one-to-one correspondence with the photocell monomers in the photocell array, and a plurality of stripes are etched on each of the windows.

[0005] Optionally, the photocell array includes a first arc trajectory, a second arc trajectory, a third arc trajectory and a fourth arc trajectory; a first photocell cell is arranged along the first arc trajectory, a second photocell cell and a third photocell cell are arranged along the second arc trajectory, a fourth photocell cell and a fifth photocell cell are arranged along the third arc trajectory, and a sixth photocell cell is arranged along the fourth arc trajectory; the first arc trajectory, the second arc trajectory, the third arc trajectory and the fourth arc trajectory are arranged concentrically and form a fan ring; the first photocell cell, the second photocell cell, the third photocell cell, the fourth photocell cell, the fifth photocell cell and the sixth photocell cell are all in the shape of a fan ring.

[0006] Optionally, the photoelectric encoder also includes a moving grating, which includes a first code channel, a second code channel and a third code channel; the first code channel is arranged corresponding to the first circular arc track, and a plurality of first stripes are arranged on the first code channel along the radius of the first circular arc track; the third code channel is arranged corresponding to the fourth circular arc track, and a plurality of second stripes are arranged on the third code channel along the radius of the fourth circular arc track; the width of the second code channel is equal to the sum of the widths of the second circular arc track and the third circular arc track, the second code channel is arranged between the first code channel and the third code channel with the center of the moving grating as the center, and a plurality of third stripes are evenly distributed on the second code channel along the radius of the second circular arc track.

[0007] Optionally, the fixed grating includes a first window and a sixth window; the first window is arranged corresponding to the first photocell monomer, and a plurality of first stripes are arranged on the first window, and the spacing between the plurality of first stripes on the first window is equal to the spacing between the plurality of first stripes on the first code channel; the sixth window is arranged corresponding to the sixth photocell monomer, and a plurality of second stripes are arranged on the sixth window, and the spacing between the plurality of second stripes on the sixth window is equal to the spacing between the plurality of second stripes on the third code channel.

[0008] Optionally, the fixed grating also includes a second window, a third window, a fourth window and a fifth window of completely consistent size and shape; the second window is arranged corresponding to the second photocell monomer, the third window is arranged corresponding to the third photocell monomer, the fourth window is arranged corresponding to the fourth photocell monomer, and the fifth window is arranged corresponding to the fifth photocell monomer; a plurality of fourth stripes are arranged on the second window, and the positions of the plurality of fourth stripes on the second window are consistent with the positions of the plurality of third stripes on the second code channel; a plurality of fifth stripes are arranged on the third window, and the plurality of fifth stripes are offset to the left on the third window by 1 / 4 of the width of the fourth stripes based on the positions of the plurality of fourth stripes on the second window; a plurality of sixth stripes are arranged on the fourth window, and the plurality of sixth stripes are offset to the left on the fourth window by 1 / 2 of the width of the fourth stripes based on the positions of the plurality of fourth stripes on the second window; a plurality of seventh stripes are arranged on the fifth window, and the plurality of seventh stripes are offset to the left on the fifth window by 3 / 4 of the width of the fourth stripes based on the positions of the plurality of fourth stripes on the second window.

[0009] Optionally, the photoelectric encoder also includes a first comparator, a second comparator and a third comparator; the first comparator is respectively connected to the third photocell cell and the fourth photocell cell, and the first comparator receives the electrical signals output by the third photocell cell and the fourth photocell cell, respectively, compares them, and outputs a first comparison signal; the second comparator is respectively connected to the second photocell cell and the fifth photocell cell, and the second comparator receives the electrical signals output by the second photocell cell and the fifth photocell cell, respectively, compares them, and outputs a second comparison signal; the third comparator is respectively connected to the first photocell cell and the sixth photocell cell, and the third comparator receives the electrical signals output by the first photocell cell and the sixth photocell cell, respectively, compares them, and outputs a third comparison signal.

[0010] Optionally, the photoelectric encoder further includes a motor; the motor is drive-connected to the dynamic grating.

[0011] Optionally, the photoelectric encoder further comprises a light emitting tube; the light emitted by the light emitting tube sequentially passes through the moving grating and the fixed grating to illuminate the photocell array.

[0012] Optionally, the photoelectric encoder further includes a circuit board; the photocell array is electrically connected to the circuit board, and the circuit board converts the light received by the photocell array into an electrical signal for output.

[0013] Optionally, the fixed grating is made of optical glass.

[0014] The photoelectric encoder provided by the utility model directly sticks the fixed grating on the photocell array, simplifies the structure of the photoelectric encoder, reduces the connection between components, and improves the reliability and stability of the photoelectric encoder. At the same time, a window corresponding to each photocell monomer in the photocell array is opened on the fixed grating, and the photocell monomer is segmented by etching stripes on the window. Compared with the prior art that directly segments on the light-receiving chip, the present application improves the feasibility of photocell array segmentation, and the segmentation is uniform and the segmentation accuracy is high, so that the photocell array obtains higher resolution energy, thereby improving the resolution of the photoelectric encoder.

[0015] Other features and advantages of the utility model will be described in the subsequent description, and partly become apparent from the description, or understood by practicing the utility model. The purpose and other advantages of the utility model can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings.

[0016] The technical solution of the utility model is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0018] Figure 1 A schematic diagram of the structure of a photoelectric cell array in a photoelectric encoder in an embodiment provided in the present application;

[0019] Figure 2 A schematic structural diagram of a fixed grating in a photoelectric encoder in an embodiment provided in the present application;

[0020] Figure 3 A schematic diagram of the overall structure of a moving grating in a photoelectric encoder in an embodiment provided in the present application;

[0021] Figure 4 A schematic diagram of the local structure of a moving grating in a photoelectric encoder in an embodiment provided in the present application;

[0022] Figure 5 A schematic diagram of the second code track of the moving grating and the stripes on the second window to the fifth window on the fixed grating in an embodiment provided by the present application;

[0023] Figure 6 A waveform diagram of the output electrical signals of the second photocell to the fifth photocell in the photoelectric encoder in an embodiment provided by the present application;

[0024] Figure 7 A line diagram of a fixed grating and a moving grating on a first code track of a photoelectric encoder in an embodiment provided in the present application;

[0025] Figure 8 A schematic diagram of the light flux of the first code channel in a photoelectric encoder in an embodiment provided in the present application;

[0026] Fig. 9 A line diagram of a fixed grating and a moving grating on the third code track of a photoelectric encoder in an embodiment provided in the present application;

[0027] Fig.10 A schematic diagram of the light flux of the third code channel in a photoelectric encoder in an embodiment provided in the present application;

[0028] Fig.11 A schematic diagram showing a comparison of the light flux on the first code channel and the third code channel in a photoelectric encoder in an embodiment provided in the present application;

[0029] Fig.12 This is a waveform diagram of the outputs of three comparators in a photoelectric encoder in an embodiment provided in the present application.

[0030] In the figure:

[0031] a, first photocell monomer; b, second photocell monomer; c, third photocell monomer; d, fourth photocell monomer; e, fifth photocell monomer; f, sixth photocell monomer;

[0032] 1. Second code channel; 2. Second window; 3. Third window; 4. Fourth window; 5. Fifth window;

[0033] U1A, the first comparator; U1B, the second comparator; U1C, the third comparator. DETAILED DESCRIPTION

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0035] In addition, 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 the indicated technical features. Therefore, the features defined as "first" and "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.

[0036] 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 it can be an indirect connection 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 invention can be understood according to specific circumstances.

[0037] The utility model provides a photoelectric encoder, comprising a photocell array and a fixed grating, wherein the fixed grating is pasted on the upper surface of the photocell array, a plurality of windows are opened on the fixed grating, the plurality of windows are arranged in one-to-one correspondence with the photocell monomers in the photocell array, and a plurality of stripes are etched on each window.

[0038] The photoelectric encoder provided by the utility model directly sticks the fixed grating on the photocell array, simplifies the structure of the photoelectric encoder, reduces the connection between components, and improves the reliability and stability of the photoelectric encoder. At the same time, a window corresponding to each photocell monomer in the photocell array is opened on the fixed grating, and the photocell monomer is segmented by etching stripes on the window. Compared with the prior art that directly segments on the light-receiving chip, the present application improves the feasibility of photocell array segmentation, and the segmentation is uniform and the segmentation accuracy is high, so that the photocell array obtains higher resolution energy, thereby improving the resolution of the photoelectric encoder.

[0039] Furthermore, the photocell array includes a first arc trajectory, a second arc trajectory, a third arc trajectory and a fourth arc trajectory; a first photocell cell a is arranged along the first arc trajectory, a second photocell cell b and a third photocell cell c are arranged along the second arc trajectory, a fourth photocell cell d and a fifth photocell cell e are arranged along the third arc trajectory, and a sixth photocell cell f is arranged along the fourth arc trajectory; the first arc trajectory, the second arc trajectory, the third arc trajectory and the fourth arc trajectory are arranged concentrically and form a fan ring; the first photocell cell a, the second photocell cell b, the third photocell cell c, the fourth photocell cell d, the fifth photocell cell e and the sixth photocell cell f are all in the shape of a fan ring.

[0040] Furthermore, the photoelectric encoder also includes a moving grating, which includes a first code channel, a second code channel 1 and a third code channel; the first code channel is arranged corresponding to the first circular arc track, and a plurality of first stripes are arranged on the first code channel along the radius of the first circular arc track; the third code channel is arranged corresponding to the fourth circular arc track, and a plurality of second stripes are arranged on the third code channel along the radius of the fourth circular arc track; the width of the second code channel 1 is equal to the sum of the widths of the second circular arc track and the third circular arc track, the second code channel 1 is arranged between the first code channel and the third code channel with the center of the moving grating as the center, and a plurality of third stripes are evenly distributed on the second code channel 1 along the radius of the second circular arc track.

[0041] Furthermore, the fixed grating includes a first window and a sixth window; the first window is arranged corresponding to the first photocell monomer a, and a plurality of first stripes are arranged on the first window, and the spacing between the plurality of first stripes on the first window is equal to the spacing between the plurality of first stripes on the first code channel; the sixth window is arranged corresponding to the sixth photocell monomer f, and a plurality of second stripes are arranged on the sixth window, and the spacing between the plurality of second stripes on the sixth window is equal to the spacing between the plurality of second stripes on the third code channel.

[0042] Further, the fixed grating also includes a second window 2, a third window 3, a fourth window 4 and a fifth window 5 of completely consistent sizes and shapes; the second window 2 is arranged corresponding to the second photocell monomer b, the third window 3 is arranged corresponding to the third photocell monomer c, the fourth window 4 is arranged corresponding to the fourth photocell monomer d, and the fifth window 5 is arranged corresponding to the fifth photocell monomer e; a plurality of fourth stripes are arranged on the second window 2, and the positions of the plurality of fourth stripes on the second window 2 are consistent with the positions of the plurality of third stripes on the second code channel 1; a plurality of fifth stripes are arranged on the third window 3, and the plurality of fifth stripes are offset to the left on the third window 3 by 1 / 4 of the width of the fourth stripes based on the positions of the plurality of fourth stripes on the second window 2; a plurality of sixth stripes are arranged on the fourth window 4, and the plurality of sixth stripes are offset to the left on the fourth window 4 by 1 / 2 of the width of the fourth stripes based on the positions of the plurality of fourth stripes on the second window 2; a plurality of seventh stripes are arranged on the fifth window 5, and the plurality of seventh stripes are offset to the left on the fifth window 5 by 3 / 4 of the width of the fourth stripes based on the positions of the plurality of fourth stripes on the second window 2.

[0043] This application specifically provides a photoelectric encoder, which decomposes the overall structure of the photoelectric encoder. First, the photocell array, such as Figure 1 As shown, the photovoltaic array specifically includes six fan-shaped photovoltaic cells, which are arranged on four arc tracks, forming a complete fan-shaped photovoltaic array as a whole. Based on the structure of the photovoltaic array provided by the present application and the positional relationship of the photovoltaic cells, a fixed grating is directly attached to the upper surface of the photovoltaic array, and for the six photovoltaic cells in the photovoltaic array, as shown in FIG. Figure 2 As shown, six windows are opened on the fixed grating corresponding to the photocell monomers, and the shape and size of each window are the same as the photocell monomers. Multiple stripes are etched on each window. After the photocell array and the fixed grating are combined, the present application specifically provides the overall structure of the moving grating as shown in FIG. Figure 3 As shown, the code channel details of the moving grating are as follows Figure 4 As shown, combined Figure 2The fringe diagram on the fixed grating specifically shows that there are three code channels on the dynamic grating, wherein the first code channel is the Z+ code channel, corresponding to the first arc track in the photocell array, and a plurality of first stripes are evenly arranged on the Z+ code channel, and a plurality of first stripes with the same number, shape and spacing as those on the Z+ code channel are arranged on the first window, so that the first photocell monomer a can generate a Z+ signal; the third code channel is the Z- code channel, corresponding to the fourth arc track in the photocell array, and a plurality of second stripes are evenly arranged on the Z- code channel, and a plurality of first stripes with the same number, shape and spacing as those on the Z+ code channel are arranged on the sixth window. -A plurality of second stripes with the same number, shape and spacing on the code channel enable the sixth photocell monomer f to generate a Z-signal; and the second code channel 1 is an AB code channel, corresponding to the second arc track and the third arc track in the photocell array, and the second code channel 1 is circumferentially arranged on the moving grating. It should be noted that since the arc of the moving grating is small when it scans the photocell array, the second arc track and the third arc track can be directly approximated as a straight line. The second code channel 1 adopts a conventional design method, and a plurality of third stripes are evenly arranged on the AB code channel, see Figure 5 , define a pair of black and white stripes as the third stripe, and the width of the third stripe is P, then the black and white stripe on the second window 2, that is, the fourth stripe, is consistent in position and size with the third stripe on the moving grating, and the remaining windows are based on the fourth stripe on the second window 2. Then, the fifth stripe on the third window 3 is compared with the fourth stripe on the second window 2 and moves 1 / 4P to the left, the sixth stripe on the fourth window 4 is compared with the fourth stripe on the second window 2 and moves 1 / 2P to the left, and the sixth stripe on the fifth window 5 is compared with the fourth stripe on the second window 2 and moves 3 / 4P to the left, and then Figure 6 As shown, the phase differences of the original signals outputted by the second photocell b, the third photocell c, the fourth photocell d and the fifth photocell e, a total of four photocells, differ by 90° electrical angle respectively.

[0044] In the specific design process of the photoelectric encoder provided in the present application, the first photocell monomer a corresponds to the Z+ code channel, and the maximum light flux is generated when the fixed grating and the moving grating code channels coincide with each other, and the smaller the light flux is at other times, the better; the sixth photocell monomer f corresponds to the Z- code channel, and the minimum light flux is generated when the fixed grating and the moving grating code channels coincide with each other, and the larger the light flux is at other times, the better; with P as the step distance (P is the width of the third stripe in the above text), the number of steps required for the fixed grating and the moving grating code channels to go from complete overlap to complete separation is calculated, and the number of steps n = a(f) width / P width. When the number of steps is small, the enumeration method can be used to implement it, and when the number of steps obtained is large, it can be obtained with the aid of a computer:

[0045] In the specific embodiment provided in the present application, the parameter 600CPR (the number of rotations in each rotation cycle) of the design moving grating is taken as n=16;

[0046] Figure 7 It is the Z+fixed grating / moving grating line mode, where the fixed grating / moving grating column corresponds to 1 for bright stripes and 0 for dark stripes. When aligned correctly, the light flux is 5 units of light. The -1, -2...-16 row items represent the number of steps of movement. Due to the symmetry of moving left and right compared to the positive alignment moment, only one side is analyzed to obtain the light flux, which is plotted as a scatter plot, such as Figure 8 shown.

[0047] Fig. 9 This is the Z-fixed grating / moving grating engraving method. The difference from Z+ is that the light flux is 0 at the moment of positive alignment, that is, it is guaranteed to be minimum. The light flux data is obtained by moving the fixed grating to the left and right, and a scatter plot is drawn, such as Fig.10 shown.

[0048] Then, the Z+ channel and Z- channel light flux diagrams obtained by the above method are plotted in the same chart. Fig.11 shown.

[0049] Furthermore, the photoelectric encoder also includes a first comparator, a second comparator and a third comparator; the first comparator is respectively connected to the third photocell cell c and the fourth photocell cell d, and the first comparator receives the electrical signals output by the third photocell cell c and the fourth photocell cell d respectively and compares them, and outputs a first comparison signal; the second comparator is respectively connected to the second photocell cell b and the fifth photocell cell e, and the second comparator receives the electrical signals output by the second photocell cell b and the fifth photocell cell e respectively and compares them, and outputs a second comparison signal; the third comparator is respectively connected to the first photocell cell a and the sixth photocell cell f, and the third comparator receives the electrical signals output by the first photocell cell a and the sixth photocell cell f respectively and compares them, and outputs a third comparison signal.

[0050] In this embodiment, the original signal requirements of the encoder have been basically achieved through the above-mentioned fixed grating line design and the moving grating line design. Fig.12 As shown, the electrical signals output by the first photocell a and the sixth photocell f are connected to the third comparator U1C to obtain a Z signal, specifically a 1T or 1 / 2T Z index signal; the electrical signals output by the third photocell c and the fourth photocell d are connected to the first comparator U1A to obtain an A signal; the electrical signals output by the second photocell b and the fifth photocell e are connected to the second comparator U1B to obtain a B signal, and the A signal is orthogonal to the B signal.

[0051] Specifically, in the above embodiment, the photoelectric encoder further includes a motor, and the motor is drivingly connected to the moving grating.

[0052] Furthermore, the photoelectric encoder also includes a light emitting tube; the light emitted by the light emitting tube sequentially passes through the moving grating and the fixed grating to illuminate the photocell array.

[0053] Furthermore, the photoelectric encoder also includes a circuit board; the photocell array is electrically connected to the circuit board, and the circuit board converts the light received by the photocell array into an electrical signal for output.

[0054] In this embodiment, after completing the arrangement of the photocell array and the arrangement of the stripes on the fixed grating and the moving grating, the overall structure of the photoelectric encoder is further improved, specifically including a motor driving the moving grating to rotate and continuously scan the photocell array, and a light-emitting tube is set to emit light to illuminate the photocell array, and the photocell array is set on a circuit board for signal output, finally forming a complete photoelectric encoder.

[0055] Specifically, in the above embodiment, the material of the fixed grating is optical glass.

[0056] In this embodiment, the fixed grating is specifically made of optical glass material, and the excellent transparency and optical properties of optical glass are utilized to effectively transmit the incident light and maintain the quality of light, thereby ensuring that the fixed grating can accurately diffract the incident light and produce clear diffraction stripes. In addition, optical glass has stable physical properties, such as thermal stability and mechanical strength, and can maintain a stable shape and performance under various environmental conditions, thereby ensuring that the fixed grating is not easily deformed or damaged during use, thereby maintaining the stability of the diffraction effect; optical glass generally also has good processing performance, and can be finely processed and surface treated to ensure the flatness of the fixed grating surface and the clarity of the stripes, thereby improving the resolution and accuracy of the photoelectric encoder.

[0057] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A photoelectric encoder, characterized in that: including a photocell array and a fixed grating; The fixed grating is pasted on the upper surface of the photovoltaic array. A plurality of windows are opened on the fixed grating. The plurality of windows are arranged corresponding to the photovoltaic cells in the photovoltaic array one by one, and a plurality of stripes are etched on each of the windows.

2. The photoelectric encoder according to claim 1, characterized in that: The photocell array includes a first arc track, a second arc track, a third arc track and a fourth arc track; A first photocell is arranged along the first arc track, a second photocell and a third photocell are arranged along the second arc track, a fourth photocell and a fifth photocell are arranged along the third arc track, and a sixth photocell is arranged along the fourth arc track; The first circular arc track, the second circular arc track, the third circular arc track and the fourth circular arc track are arranged cocentrically and form a sector ring; The first photocell unit, the second photocell unit, the third photocell unit, the fourth photocell unit, the fifth photocell unit and the sixth photocell unit are all in the shape of a fan ring.

3. The photoelectric encoder according to claim 2, characterized in that: The photoelectric encoder further includes a moving grating, and the moving grating includes a first code channel, a second code channel and a third code channel; The first code track is arranged corresponding to the first circular arc track, and a plurality of first stripes are arranged on the first code track along the radius of the first circular arc track; The third code track is arranged corresponding to the fourth circular arc track, and a plurality of second stripes are arranged on the third code track along the radius of the fourth circular arc track; The width of the second code channel is equal to the sum of the widths of the second arc track and the third arc track. The second code channel is arranged between the first code channel and the third code channel with the center of the moving grating as the center of the circle, and a plurality of third stripes are evenly distributed on the second code channel along the radius of the second arc track.

4. The photoelectric encoder according to claim 3, characterized in that: The fixed grating includes a first window and a sixth window; The first window is arranged corresponding to the first photocell monomer, a plurality of the first stripes are arranged on the first window, and a spacing between the plurality of the first stripes on the first window is equal to a spacing between the plurality of the first stripes on the first code channel; The sixth window is arranged corresponding to the sixth photovoltaic cell unit, a plurality of second stripes are arranged on the sixth window, and the spacing between the plurality of second stripes on the sixth window is equal to the spacing between the plurality of second stripes on the third code channel.

5. The photoelectric encoder according to claim 4, characterized in that: The fixed grating also includes a second window, a third window, a fourth window and a fifth window with completely identical sizes and shapes; The second window is arranged corresponding to the second photocell monomer, the third window is arranged corresponding to the third photocell monomer, the fourth window is arranged corresponding to the fourth photocell monomer, and the fifth window is arranged corresponding to the fifth photocell monomer; A plurality of fourth stripes are arranged on the second window, and positions of the plurality of fourth stripes on the second window are consistent with positions of the plurality of third stripes on the second code channel; The third window is provided with a plurality of fifth stripes, the plurality of fifth stripes are based on the positions of the plurality of fourth stripes on the second window, and are shifted to the left on the third window by 1 / 4 of the width of the fourth stripes; A plurality of sixth stripes are arranged on the fourth window, and the plurality of sixth stripes are based on the positions of the plurality of fourth stripes on the second window and are shifted to the left by 1 / 2 of the width of the fourth stripes on the fourth window; A plurality of seventh stripes are arranged on the fifth window. The plurality of seventh stripes are based on the positions of the plurality of fourth stripes on the second window and are shifted to the left by 3 / 4 of the width of the fourth stripes on the fifth window.

6. The photoelectric encoder according to claim 5, characterized in that: The photoelectric encoder further includes a first comparator, a second comparator and a third comparator; The first comparator is connected to the third photocell monomer and the fourth photocell monomer respectively, and the first comparator receives and compares the electrical signals output by the third photocell monomer and the fourth photocell monomer respectively, and outputs a first comparison signal; The second comparator is connected to the second photocell monomer and the fifth photocell monomer respectively, and the second comparator receives and compares the electrical signals output by the second photocell monomer and the fifth photocell monomer respectively, and outputs a second comparison signal; The third comparator is connected to the first photocell and the sixth photocell respectively, receives and compares the electrical signals output by the first photocell and the sixth photocell respectively, and outputs a third comparison signal.

7. The photoelectric encoder according to claim 3, characterized in that: The photoelectric encoder also includes a motor; The motor is drivingly connected to the dynamic grating.

8. The photoelectric encoder according to claim 7, characterized in that: The photoelectric encoder also includes a light emitting tube; The light emitted by the light emitting tube passes through the moving grating and the fixed grating in sequence and irradiates the photocell array.

9. The photoelectric encoder according to claim 8, characterized in that: The photoelectric encoder also includes a circuit board; The photovoltaic array is electrically connected to the circuit board, and the circuit board converts the light received by the photovoltaic array into an electrical signal for output.

10. The photoelectric encoder according to claim 1, characterized in that: The material of the fixed grating is optical glass.

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