Color wheel device and projection device

Abstract

The utility model discloses a color wheel device and a projection device, and the color wheel device comprises a color wheel which is provided with a wavelength conversion layer and is used for converting excitation light irradiated on the wavelength conversion layer into excited light and emitting the excited light; the rotating shaft is connected with the color wheel and used for driving the color wheel to rotate under the action of driving force, and a plurality of concave surfaces and a plurality of convex surfaces which are alternately distributed are formed around the rotating shaft in the circumferential direction of the rotating shaft; and the rotating speed detection assembly is used for emitting optical signals to the plurality of concave surfaces and the plurality of convex surfaces and receiving the optical signals reflected by the plurality of concave surfaces and the plurality of convex surfaces so as to detect the rotating speed of the color wheel based on the change of the optical signals. According to the color wheel device, the number of times of adjusting the rotating speed of the color wheel can be increased through the newly-added pulse feedback signal in the unit rotating period, so that the rotating speed of the driving assembly is adjusted in time when rotating speed fluctuation occurs, rotating speed matching is completed as soon as possible, and then the stability and reliability of the color wheel device are improved.

Description

Technical Field

[0001] The present application relates to the field of optical technologies, and particularly to a color wheel device and a projection device. Background Art

[0002] A color wheel generally includes a substrate that can rotate rapidly, at least one phosphor layer disposed on the substrate, and a fluorescence filter disposed on one side of the phosphor layer. In order to accurately project corresponding color images, it is necessary to synchronize the color wheel with a DMD (digital micromirror device). Therefore, it is necessary to detect the relative position and rotation speed of the color wheel.

[0003] The rotation of the color wheel is usually achieved by a motor, and the rotation state of the color wheel is determined by the rotation state of the motor shaft. In the prior art, usually only one black glue monitoring point is provided on the motor shaft driving the color wheel. The starting position of the motor shaft is judged by the pulse signal output by the optical sensor and the reflection signal reflected by the black glue detection point. At the same time, the rotation speed of the motor shaft is also calculated by the period of the pulse signal.

[0004] However, the above device can only detect a pulse feedback signal once when the color wheel rotates one circle, and the detection interval time is relatively long. When the motor is interfered by the outside world and the speed fluctuates, the optical sensor often cannot detect the speed fluctuation in time, which easily leads to the rotation speed of the color wheel not matching, and then losing synchronization with the synchronization signal, thus reducing the stability and reliability of the color wheel device. Summary of the Utility Model

[0005] The main technical problem to be solved by the present application is to provide a color wheel device and a projection device, which can solve the problem that the prior art cannot detect the rotation speed fluctuation in time, resulting in the reduction of the stability and reliability of the color wheel device.

[0006] To solve the above technical problem, the first technical solution adopted by the present application is to provide a color wheel device, including: a color wheel having a wavelength conversion layer for converting the excitation light irradiated on the wavelength conversion layer into stimulated light and emitting it; a rotating shaft connected to the color wheel for driving the color wheel to rotate under the action of a driving force, and a plurality of concave surfaces and a plurality of convex surfaces are alternately distributed around the rotating shaft and along the circumferential direction of the rotating shaft; a rotation speed detection component for emitting an optical signal to the plurality of concave surfaces and the plurality of convex surfaces, and receiving the optical signal reflected back by the plurality of concave surfaces and the plurality of convex surfaces, so as to detect the rotation speed of the color wheel based on the change of the optical signal.

[0007] Wherein, the plurality of concave surfaces are part of the rotating shaft body, and the plurality of convex surfaces form a ring sleeved on the outer periphery of the rotating shaft.

[0008] Wherein, the plurality of concave surfaces and the plurality of convex surfaces jointly form a ring, and the ring is sleeved on the outer periphery of the rotating shaft.

[0009] The wavelength conversion layer includes at least two color partitions, each color partition is configured to emit light of a corresponding color, and the boundary line between two adjacent color partitions corresponds to the edge of the convex surface; wherein each color partition corresponds to a concave surface and a convex surface respectively.

[0010] The rotational speed detection component includes a light sensor, a filter circuit connected to the light sensor, and a comparator circuit connected to the filter circuit; wherein the light sensor is configured to emit light signals to a plurality of concave surfaces and a plurality of convex surfaces, and receive the light signals reflected back by the plurality of concave surfaces and the plurality of convex surfaces, so as to generate signals with different amplitudes and widths based on the reflected light signals, and output the signals with different amplitudes and widths to the comparator circuit through the filter circuit, so as to output a low-level pulse corresponding to the concave surface and a high-level pulse corresponding to the convex surface through the comparator circuit.

[0011] The plurality of concave surfaces and the plurality of convex surfaces are both fan-shaped rings, the fan-shaped radii corresponding to the plurality of convex surfaces are all equal, and the fan-shaped radii and fan-shaped angles corresponding to the plurality of concave surfaces are all equal.

[0012] The plurality of convex surfaces include a first convex surface and at least one second convex surface; the fan-shaped angle corresponding to the first convex surface is not equal to the fan-shaped angle corresponding to the second convex surface; the fan-shaped angles corresponding to the plurality of second convex surfaces are all equal.

[0013] A black induction layer is provided on the outer surface of the rotating shaft.

[0014] The color wheel device further includes a control device, and the control device is communicatively connected to a motor that drives the rotating shaft to rotate and the rotational speed detection component.

[0015] To solve the above technical problems, the second technical solution adopted by this application is to provide a projection device, including an excitation light source, a display component, a projection lens, and the above-mentioned color wheel device.

[0016] The beneficial effects of the present application are as follows: The present application provides a color wheel device and a projection device. By forming a plurality of concave surfaces and a plurality of convex surfaces that are alternately distributed around the rotation axis and along the circumferential direction of the rotation axis, a plurality of segmented structures with height differences can be formed on the sensing surface of the color wheel. The convex surfaces form high-sensing surfaces, and the concave surfaces form low-sensing surfaces. Further, by the rotation speed detection component emitting optical signals to the plurality of concave surfaces and the plurality of convex surfaces and receiving the optical signals reflected back by the concave surfaces and the convex surfaces, a plurality of pulse feedback signals can be generated, thereby increasing the detection frequency of the rotation speed of the color wheel by the rotation speed detection component, and then improving the detection accuracy of the rotation speed of the color wheel. Further, by increasing the detection frequency of the rotation speed of the color wheel by the rotation speed detection component, the number of times of adjusting the rotation speed of the color wheel can be increased by the newly added pulse feedback signals within a unit rotation period, so as to timely adjust the rotation speed of the driving component when there is a rotation speed fluctuation, thereby completing the rotation speed matching as soon as possible, and then improving the stability and reliability of the color wheel device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 is a three-dimensional structural schematic diagram of an embodiment of the color wheel device of the present application;

[0019] Figure 2 is Figure 1 the front view of the color wheel device in ;

[0020] Figure 3 is Figure 1 the left view of the color wheel device in ;

[0021] Figure 4 is Figure 1 the structural diagram of the rotation speed detection component in ;

[0022] Figure 5 is a schematic diagram of an embodiment of the pulse feedback signal generated by the rotation speed detection component based on the color wheel;

[0023] Figure 6 is a corresponding schematic diagram of the pulse feedback signal collected by the control device and the vertical synchronization pulse signal. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0025] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The singular forms "a", "the" and "said" used in the embodiments of the present application and the appended claims are also intended to include the plural forms unless clearly indicated otherwise in the context. "Plural" generally includes at least two, but does not exclude the case of including at least one.

[0026] It should be understood that the term "and / or" used herein is only a kind of association relationship describing associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0027] It should be understood that the term "comprising", "including" or any other variant used herein is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, the elements defined by the statement "including..." do not exclude the existence of additional identical elements in the process, method, article or device including the said elements.

[0028] The rotation of the color wheel is usually realized by a motor, and the rotation state of the color wheel is determined by the rotation state of the motor shaft. In the prior art, usually only one black glue monitoring point is provided on the motor shaft driving the color wheel, and the starting position of the motor shaft is judged by the pulse signal output by the optical sensor and the reflection signal reflected by the black glue detection point, and at the same time, the rotation speed of the motor shaft is calculated by the period of the pulse signal. However, the above device can only detect the pulse signal once when the color wheel rotates one circle, and the detection interval time is relatively long. When the motor is interfered by the outside world and the speed fluctuates, the optical sensor often cannot detect the speed fluctuation in time, which easily leads to the mismatch of the rotation speed of the color wheel, and then loses synchronization with the synchronization signal, thus reducing the stability and reliability of the color wheel device.

[0029] Based on the above situation, the present application provides a color wheel device and a projection device, which can solve the problem that the prior art cannot detect the speed fluctuation in time, resulting in the reduction of the stability and reliability of the color wheel device.

[0030] The color wheel device provided by the present application includes: a color wheel having a wavelength conversion layer for converting the excitation light irradiated on the wavelength conversion layer into stimulated light and emitting it; a rotating shaft connected to the color wheel for driving the color wheel to rotate under the action of a driving force, and concave surfaces and convex surfaces are alternately distributed around the rotating shaft and along the circumferential direction of the rotating shaft; a rotational speed detection component for emitting an optical signal to the concave surfaces and convex surfaces and receiving the optical signal reflected back via the concave surfaces and convex surfaces to detect the rotational speed of the color wheel based on the change in the optical signal. By forming concave surfaces and convex surfaces that are alternately distributed around the rotating shaft and along the circumferential direction of the rotating shaft, a plurality of segmented structures with height differences can be formed on the sensing surface of the color wheel, and a high-sensing surface is formed by the convex surface, and the concave surface forms a low-sensing surface. Further, by the rotational speed detection component emitting an optical signal to the concave surfaces and convex surfaces and receiving the optical signal reflected back via the concave surfaces and convex surfaces, a plurality of pulse feedback signals can be generated within a unit rotation period (when the color wheel rotates one circle), thereby increasing the detection frequency of the rotational speed of the color wheel by the rotational speed detection component, and then improving the detection accuracy of the rotational speed of the color wheel. Further, by increasing the detection frequency of the rotational speed of the color wheel by the rotational speed detection component, the number of times of adjusting the rotational speed of the color wheel can be increased by the newly added pulse feedback signals within a unit rotation period, so as to timely adjust the rotational speed of the driving component when there is a rotational speed fluctuation, thereby quickly completing the rotational speed matching, and then improving the stability and reliability of the color wheel device.

[0031] To illustrate the specific structure of the color wheel device of the present application, please refer to Figure 1 、 Figure 2 And Figure 3 , Figure 1 is a three-dimensional structural schematic diagram of an embodiment of the color wheel device of the present application, Figure 2 is Figure 1 the front view of the color wheel device in Figure 3 is Figure 1 the left view of the color wheel device in

[0032] In this embodiment, the color wheel device 100 includes a color wheel 10, a rotating shaft 20, and a rotational speed detection component 30. Among them, the color wheel 10 includes a substrate 11 and a wavelength conversion layer provided on one side surface of the substrate. The wavelength conversion layer is used for converting the excitation light irradiated on the wavelength conversion layer into stimulated light and emitting it. The rotating shaft 20 is connected to the color wheel 10 for driving the color wheel 10 to rotate under the action of a driving force, and a plurality of concave surfaces 41 and a plurality of convex surfaces 42 are alternately distributed around the rotating shaft 20 and along the circumferential direction of the rotating shaft 20. The rotational speed detection component 30 is used for emitting an optical signal to the plurality of concave surfaces 41 and the plurality of convex surfaces 42 and receiving the optical signal reflected back via the plurality of concave surfaces 41 and the plurality of convex surfaces 42 to detect the rotational speed of the color wheel 10 based on the change in the optical signal.

[0033] In this embodiment, the multiple concave surfaces 41 and the multiple convex surfaces 42 may belong to different structural members or the same structural member, and the present application does not limit this.

[0034] In some embodiments, as Figure 1 shown, the multiple concave surfaces 41 are part of the main body of the rotating shaft 20, and the multiple convex surfaces 42 form a ring sleeved around the periphery of the rotating shaft 20. In some specific embodiments, the ring formed by the multiple convex surfaces 42 is part of the substrate 11 and is integrally formed with the substrate 11. In some other specific embodiments, the ring is an independent structural member and is welded to the substrate 11 or the periphery of the rotating shaft 20, and the present application does not limit this.

[0035] In some other embodiments, the multiple concave surfaces 41 and the multiple convex surfaces 42 together form a ring that is sleeved around the periphery of the rotating shaft 20. Among them, the inner ring radii of the concave surfaces 41 and the convex surfaces 42 are equal, and the outer ring radius of the convex surfaces 42 is greater than the outer ring radius of the concave surfaces 41 to form a step difference. In some specific embodiments, the ring formed by the multiple concave surfaces 41 and the multiple convex surfaces 42 together is part of the substrate 11 and is integrally formed with the substrate 11. In some other specific embodiments, the ring is an independent structural member and is welded to the substrate 11 or the periphery of the rotating shaft 20, and the present application does not limit this.

[0036] In this embodiment, the rotating shaft 20 is driven by a motor (not shown in the figure), and the rotating shaft 20 is fixedly connected to the substrate 11.

[0037] In this embodiment, the substrate 11 is a circular runner, and the wavelength conversion layer is disposed on one side surface of the substrate 11 facing away from the rotating shaft 20. Among them, the wavelength conversion layer is disposed on the outer side of the substrate 11 and is in a circular ring shape.

[0038] In this embodiment, the wavelength conversion layer includes at least one wavelength conversion material.

[0039] Among them, the wavelength conversion material is used to absorb incident light of a certain wavelength and is excited to emit outgoing light with a wavelength different from that of the incident light. The wavelength conversion materials include phosphors, fluorescent dyes, quantum dots, etc., and usually phosphors are the most commonly used.

[0040] In some embodiments, the wavelength conversion material in the wavelength conversion layer is a phosphor.

[0041] In this embodiment, the wavelength conversion layer may include multiple fluorescent materials to form a multi-color segment component, or may only include one fluorescent material to form a single-color whole circle.

[0042] Among them, the fluorescent material includes one or more of a red fluorescent material, a green fluorescent material, a yellow fluorescent material, and a blue fluorescent material. When the excitation light is blue excitation light, the red fluorescent material is used to convert the blue excitation light into red fluorescence, the green fluorescent material is used to convert the blue excitation light into green fluorescence, and the yellow fluorescent material is used to convert the blue excitation light into yellow fluorescence. When the excitation light is ultraviolet or near-ultraviolet excitation light, the red fluorescent material is used to convert the ultraviolet or near-ultraviolet excitation light into red fluorescence, the green fluorescent material is used to convert the ultraviolet or near-ultraviolet excitation light into green fluorescence, the yellow fluorescent material is used to convert the ultraviolet or near-ultraviolet excitation light into yellow fluorescence, and the blue fluorescent material is used to convert the ultraviolet or near-ultraviolet excitation light into blue fluorescence.

[0043] In some embodiments, the wavelength conversion layer includes at least two color partitions, and each color partition is used to emit light of a corresponding color. Fluorescent materials of at least two colors are respectively disposed in different partitions of the wavelength conversion layer to form a plurality of color partitions. The fluorescent materials of the plurality of color partitions respectively form a multi-color segment assembly with the substrate 11 at corresponding angles and are sequentially arranged around the rotation axis 20 to emit light of different colors in sequence.

[0044] In other embodiments, when the wavelength conversion layer only includes a fluorescent material of one color, the wavelength conversion layer and the substrate 11 form a single-color complete circle.

[0045] In some embodiments, a flow disturbance assembly 50 is further disposed on one surface of the substrate 11 close to the rotation axis 20. The flow disturbance assembly 50 is disposed outside the convex surface 42 and includes a plurality of flow disturbance vanes. Among them, the plurality of flow disturbance vanes are uniformly distributed along the circumferential direction of the rotation axis 20 and are used to enhance the heat dissipation performance of the color wheel device 100.

[0046] In this embodiment, the rotation speed detection assembly 30 is disposed close to the rotation axis 20 to ensure that the optical signal (pulse signal) emitted by the rotation speed detection assembly 30 can be emitted onto the plurality of concave surfaces 41 and the plurality of convex surfaces 42, and to receive the optical signal reflected back via the plurality of concave surfaces 41 and the plurality of convex surfaces 42.

[0047] Please refer to Figure 4 , Figure 4 is Figure 1 the structural diagram of the rotation speed detection assembly in

[0048] In this embodiment, the rotational speed detection assembly 30 includes a light sensor 31, a filter circuit 32 connected to the light sensor 31, and a comparator circuit 33 connected to the filter circuit 32. Among them, the light sensor 31 is used to emit light signals to a plurality of concave surfaces 41 and a plurality of convex surfaces 42, and receive the light signals reflected back via the plurality of concave surfaces 41 and the plurality of convex surfaces 42, so as to generate signals with different amplitudes and widths based on the reflected light signals, and output the signals with different amplitudes and widths to the comparator circuit 33 through the filter circuit 32, so as to output a low-level pulse corresponding to the concave surface 41 and a high-level pulse corresponding to the convex surface 42 through the comparator circuit 33.

[0049] Among them, both the light sensor 31 and the comparator circuit 33 are powered by corresponding power supplies, and the comparator circuit 33 is also communicatively connected to the control device. In some specific embodiments, the control device is a microcontroller unit (MCU).

[0050] Among them, the concave surface 41 corresponds to a low-sensing surface, and the convex surface 42 corresponds to a high-sensing surface.

[0051] Specifically, the light sensor 31 is used to emit pulse signals and receive different pulse signals reflected by a plurality of concave surfaces 41 (i.e., the main body of the rotating shaft 20) and a plurality of convex surfaces 42. When the light sensor 31 senses that different pulse signals correspond to different high and low sensing surfaces and different widths, signals with different amplitudes and widths will be generated, and the signals with different amplitudes and widths will be output to the comparator circuit 33 through the filter circuit 32, so as to output a color wheel feedback pulse signal after comparison by the comparator circuit 33, where a high-level pulse is output corresponding to the high-sensing surface, and a low-level pulse is output corresponding to the low-sensing surface.

[0052] In this embodiment, both the plurality of concave surfaces 41 and the plurality of convex surfaces 42 are fan-shaped rings, the sector radii corresponding to the plurality of convex surfaces 42 are all equal, and the sector radii and sector angles corresponding to the plurality of concave surfaces 41 are all equal.

[0053] Among them, the fact that the sector radii and sector angles corresponding to the plurality of concave surfaces 41 are all equal means that the sector radius corresponding to each concave surface 41 is the radius of the rotating shaft 20, and the plurality of convex surfaces 42 are equally spaced.

[0054] Among them, the plurality of convex surfaces 42 and the plurality of concave surfaces 41 form a complete circle around the rotating shaft 20. The convex surfaces 42 are used to block the rotating shaft 20, and the concave surfaces 41 are the exposed rotating shaft 20.

[0055] Understandably, when the convex surface 42 rotates above the rotation speed detection component 30, the first distance formed between the convex surface 42 and the rotation speed detection component 30 is less than the second distance formed between the concave surface 41 and the rotation speed detection component 30 at the same position. That is, each convex surface 42 and an adjacent concave surface 41 form a segmented structure with a height difference. When there are multiple convex surfaces 42 and multiple concave surfaces 41, multiple segmented structures with height differences are correspondingly formed on the sensing surface of the color wheel 10.

[0056] Further, when the rotation speed detection component 30 emits a pulse signal at a fixed position, the time for the pulse signal to reach the convex surface 42 rotating above this fixed position is shorter than the time for the pulse signal to reach the concave surface 41 rotating above this fixed position. It is equivalent that each convex surface 42 forms a high-sensing surface, while the concave surface 41 located between adjacent convex surfaces 42 forms a low-sensing surface.

[0057] Further, since the rotation speed detection component 30 can generate different pulse feedback signals when receiving different signals reflected by the high-sensing surface and the low-sensing surface, when the color wheel 10 rotates one circle, the rotation speed detection component 30 can generate multiple pulse feedback signals based on the optical signals reflected by multiple concave surfaces 41 and multiple convex surfaces 42, and each segmented structure corresponds to a high-level pulse and a low-level pulse.

[0058] Different from the prior art where the color wheel rotates one circle and can only generate one pulse feedback signal once, and the rotation speed is adjusted based on this pulse feedback signal, in this embodiment, every time the color wheel 10 rotates one circle, multiple pulse feedback signals can be generated through the rotation speed detection component 30, thereby increasing the detection frequency of the rotation speed detection component 30 for the rotation speed of the color wheel 10, and then improving the detection accuracy of the rotation speed of the color wheel 10. Further, by increasing the detection frequency of the rotation speed detection component 30 for the rotation speed of the color wheel 10, the number of times of adjusting the rotation speed of the color wheel 10 can be increased through the newly added pulse feedback signals within a unit rotation period, so as to adjust the rotation speed of the drive component 20 in time when there is a rotation speed fluctuation, thereby completing the rotation speed matching as soon as possible, and then improving the stability and reliability of the color wheel device 100.

[0059] In some embodiments, a black sensing layer is provided on the outer surface of the rotating shaft 20.

[0060] In some specific embodiments, the black sensing layer is an attached black tape.

[0061] Among them, when the optical signal (infrared light) emitted by the optical sensor 31 is emitted to the black sensing layer, it will be absorbed by the black sensing layer and not be reflected. It is equivalent that the optical signal received by the optical reactor 31 is interrupted when entering the concave surface 41 through the edge of the convex surface 42, and then different detection points corresponding to different segmented structures can be better distinguished through the interruption signal.

[0062] In some embodiments, the wavelength conversion layer includes at least two color partitions, each color partition is configured to emit light of a corresponding color, and the boundary line between two adjacent color partitions corresponds to the edge of the convex surface 42. Wherein, each color partition corresponds to a concave surface 41 and a convex surface 42 respectively.

[0063] In some specific embodiments, taking a four-segment color wheel as an example, the wavelength conversion layer includes four color partitions, and 4 convex surfaces 42 are arranged on the substrate 11 at equal intervals. Each color partition corresponds to a convex surface 42 and a concave surface 41, and the boundary line between two adjacent color partitions corresponds to the edge of the convex surface 42.

[0064] It can be understood that by combining the position of the starting end of different color partitions with the edge of the convex surface 42, the correlation accuracy between each segmented structure and the phosphor layer corresponding to different color partitions can be improved, so as to more accurately identify the relative positions corresponding to different color partitions on the color wheel 10.

[0065] In the prior art, segmented induction detection is achieved through the different reflectivities of infrared light by different materials. Multi-material induction requires increasing the types of materials and high-precision assembly processes. At the same time, as the number of segments increases, the process cost will increase almost exponentially.

[0066] Different from the prior art, this embodiment is based on the correlation principle between the induction distance and the signal strength of the optical sensor, and uses the height difference of different induction surfaces of multiple segmented structures to distinguish pulse feedback signals, which can increase the number of induction areas and improve the correlation accuracy between the induction area and the color wheel phosphor at low cost. Further, by sticking another layer of black tape on the rotating shaft 20 to form a black induction layer, the pulse feedback signals of different segmented detection points can be better distinguished, and the operation of sticking the black tape on the outer periphery of the rotating shaft 20 is simple, does not involve positioning and high-precision assembly processes, and does not require additional detection equipment to check the position of the black tape monomer, which can further reduce the processing difficulty of the rotating shaft 20 and the overall processing cost.

[0067] Please refer to Figure 2 and Figure 5 , Figure 5 which is a schematic diagram of an embodiment of the rotational speed detection component based on the pulse feedback signal generated by the color wheel.

[0068] In this embodiment, the multiple convex surfaces 42 include a first convex surface 421 and at least one second convex surface 422. Wherein, the sector angle corresponding to the first convex surface 421 is not equal to the sector angle corresponding to the second convex surface 422. The sector angles corresponding to the multiple second convex surfaces 422 are all equal.

[0069] In some embodiments, such as Figure 2As shown, the sector angle corresponding to the first convex surface 421 is greater than the sector angle corresponding to the second convex surface 422.

[0070] In other embodiments, the sector angle corresponding to the first convex surface 421 is less than the sector angle corresponding to the second convex surface 422, as long as the angles corresponding to the first convex surface 421 and the second convex surface 422 are different, and the present application does not limit this.

[0071] In some embodiments, the sector angle corresponding to each concave surface 41 is less than the sector angle corresponding to the first convex surface 421 and greater than the sector angle corresponding to the second convex surface 422.

[0072] In other embodiments, the sector angle corresponding to each concave surface 41 is less than the sector angle corresponding to the first convex surface 421 and equal to the sector angle corresponding to the second convex surface 422, and the present application does not limit this.

[0073] In some embodiments, the edge of the first convex surface 421 corresponds to the starting position of the color wheel 10.

[0074] In some embodiments, the plurality of convex surfaces 42 includes a first convex surface 421 and three second convex surfaces 422. In some specific embodiments, each first convex surface 421 and an adjacent concave surface 41 correspond to a color partition, and each second convex surface 422 and an adjacent concave surface 41 also respectively correspond to a color partition to form a four-segment color wheel.

[0075] The pulse feedback signal generated by the rotation speed detection component 30 will be described below by taking the above four-segment color wheel as an example. As Figure 2 As Figure 5 shown, when the color wheel 10 rotates from time t 1 to time t 5 it is exactly one circle (360°), and four high-low level pulses are output. The first high-low level pulse starts at time t 1 and ends at time t 2 corresponding to the first convex surface 421 and a concave surface 41, where the high-level pulse corresponds to the high induction surface formed by the first convex surface 421, and the low-level pulse corresponds to the low induction surface formed by the concave surface 41. The second high-low level pulse starts at time t 2 and ends at time t 3 corresponding to the first second convex surface 422 and a concave surface 41, where the high-level pulse corresponds to the high induction surface formed by the second convex surface 422, and the low-level pulse corresponds to the low induction surface formed by the concave surface 41. The third high-low level pulse starts at time t 3 and ends at time t 4At this moment, it corresponds to the second second convex surface 422 and a concave surface 41, where the high-level pulse corresponds to the high induction surface formed by the second convex surface 422, and the low-level pulse corresponds to the low induction surface formed by the concave surface 41. The fourth high and low level pulse starts from t 4 At this moment and ends at t 5 At this moment, it corresponds to the third second convex surface 422 and a concave surface 41, where the high-level pulse corresponds to the high induction surface formed by the second convex surface 422, and the low-level pulse corresponds to the low induction surface formed by the concave surface 41.

[0076] Among them, the angle corresponding to the first high-level pulse is θ 1 , and the angles corresponding to the remaining three high-level pulses are all θ 3 , and the angles corresponding to the four low-level pulses are all θ 2 , where, θ 1 > θ 3 > θ 2 .

[0077] It can be understood that the angle occupied by the high-level pulse for identifying the starting position of the color wheel 10 is greater than the angles occupied by the remaining high-level pulses, which can improve the recognition accuracy of the initial position. At the same time, making the angles occupied by the three high-level pulses at non-starting positions the same, and making the angles occupied by the four low-level pulses the same, can improve the stability of rotational speed detection.

[0078] Furthermore, in this embodiment, the color wheel device 100 further includes a control device (not shown in the figure), and the control device is communicatively connected to the motor that drives the rotation of the rotating shaft 20 and the rotational speed detection component 30.

[0079] In some embodiments, the control device is a Microcontroller Unit (MCU).

[0080] In some embodiments, the control device is used to control the rotational speed of the motor to adjust the rotational speeds of the rotating shaft 20 and the color wheel 10.

[0081] In some embodiments, the control device is coupled to the comparator circuit 33 of the rotational speed detection component 30 and is used to calculate the interval time for triggering an interrupt according to the pulse feedback signal output by the comparator circuit 33.

[0082] Specifically, when the color wheel 10 is an N-segment color wheel, since each segment of the color wheel corresponds to a convex surface 42 and a concave surface 41, each time the pulse signal touches the edge of the convex surface 42, an interruption will be triggered, and the N-segment color wheel will trigger N interruptions. The control device can calculate the absolute rotational speed of the color wheel 10 by calculating the interval time of the interruptions, and then calculate the error from the target rotational speed based on the absolute rotational speed. Since the N-segment color wheel supports calculating the error once for each detection, N errors can be calculated within a unit rotation period. The control device re-performs PID calculation (i.e., calculates based on the proportional (P), integral (I), and derivative (D) of the deviation) based on the rotational speed error calculated each time, and then converts it into a calculation of the PWM (Pulse Width Modulation) duty cycle. By adjusting the PWM duty cycle, the rotational speed of the color wheel is changed to perform speed matching in a timely manner, thereby improving the response speed in different situations and then improving the rotational speed matching accuracy of the color wheel 10. Further, since the width of the high-level pulse at the initial position is inconsistent with the width of the high-level pulses at other positions, the interval time of the triggered interruption is different from the interval time of the triggered interruptions of the other high-level pulses. By calculating the interval time of the triggered interruption, the control device can accurately identify the initial position of the color wheel 10.

[0083] In some embodiments, the control device simultaneously acquires the VSYNC (Vertical Sync Pulse) signal and the multi-segment pulse feedback signal of the color wheel 10.

[0084] Among them, there will be a certain phase difference between the pulse feedback signal at the initial position of the color wheel 10 and the VSYNC signal, that is, color wheel delay. The color wheel 10 will generate N segments of high and low pulse feedback signals within a unit rotation period. Each time a segment of high and low pulse feedback signal is generated, it will trigger the control device to calculate the interval time (i.e., phase difference) with the VSYNC signal once. The control device will calculate a phase error based on the phase difference. That is, the color wheel 10 will calculate N phase errors when it rotates one circle. The control device re-performs PID calculation based on the phase error calculated each time, and then converts it into a PWM duty cycle, and then changes the rotational speed of the color wheel by adjusting the PWM duty cycle to adjust the phase error.

[0085] Specifically, please refer to Figure 6 , Figure 6 is a corresponding schematic diagram of the pulse feedback signal and the vertical sync pulse signal acquired by the control device. When the color wheel 10 is a four-segment color wheel, it will generate 4 segments of high and low pulse feedback signals within a unit rotation period. Each time a segment of high and low pulse feedback signal is generated, it will trigger the control device to calculate the interval time (i.e., phase difference) with the VSYNC signal once. The control device will calculate a phase error t 0 based on the phase difference, that is, the color wheel 10 will calculate 4 phase errors t when it rotates one circle 0, the control device re - performs PID calculation based on the phase error calculated each time, then converts it into a PWM duty cycle, and then changes the rotational speed of the color wheel by adjusting the PWM duty cycle to adjust the phase error.

[0086] Understandably, by the control device performing N times of phase synchronization detection within a unit rotation period, the phase synchronization time can be shortened to more accurately locate the real - time angle of the color wheel 10, thereby improving the phase synchronization accuracy between the color wheel 10 and the frame signal, and then further improving the stability and reliability of the color wheel device 100.

[0087] In some embodiments, the color wheel 10 can also be an eight - segment color wheel or a color wheel with more segments.

[0088] Understandably, as the number of color partitions corresponding to the color wheel 10 and the number of convex surfaces 42 and concave surfaces 41 increase, the number of segmented structures increases, the corresponding detection points and detection times increase, the number of rotational speed adjustment times within a unit rotation period also increases, and the accuracy of phase synchronization detection is also higher.

[0089] Correspondingly, the present application provides a projection device, including an excitation light source, a display component, a projection lens, and the above - mentioned color wheel device.

[0090] Understandably, by forming a plurality of segmented structures with height differences on the sensing surface of the color wheel, the number of times of adjusting the rotational speed of the color wheel can be increased through the newly added pulse feedback signal within a unit rotation period, so as to timely adjust the rotational speed of the driving component when there is a rotational speed fluctuation, thereby quickly completing the rotational speed matching, improving the stability and reliability of the color wheel device, making the projected color image more accurate, and then improving the display effect of the projection device.

[0091] Different from the prior art, in the present application, by forming a plurality of alternately distributed concave surfaces and convex surfaces around the rotation axis and along the circumferential direction of the rotation axis, a plurality of segmented structures with height differences can be formed on the sensing surface of the color wheel, and the convex surfaces form high - sensing surfaces, and the concave surfaces form low - sensing surfaces. Further, by the rotational speed detection component emitting light signals to the plurality of concave surfaces and convex surfaces and receiving the light signals reflected back by the concave surfaces and convex surfaces, a plurality of pulse feedback signals can be generated, thereby increasing the detection frequency of the rotational speed detection component for the color wheel rotational speed, and then improving the detection accuracy of the color wheel rotational speed. Further, by increasing the detection frequency of the rotational speed detection component for the color wheel rotational speed, the number of times of adjusting the rotational speed of the color wheel can be increased through the newly added pulse feedback signal within a unit rotation period, so as to timely adjust the rotational speed of the driving component when there is a rotational speed fluctuation, thereby quickly completing the rotational speed matching, and then improving the stability and reliability of the color wheel device.

[0092] The above are only the embodiments of the present application, and do not thus limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall similarly be included within the patent protection scope of the present application.

Claims

1. A color wheel device, characterized in that: include: The color wheel has a wavelength conversion layer, which is used to convert the excitation light irradiated on the wavelength conversion layer into the stimulated light and emit the stimulated light; A rotating shaft connected to the color wheel and used to drive the color wheel to rotate under the action of a driving force, and a plurality of concave surfaces and a plurality of convex surfaces are formed around the rotating shaft and along the circumferential direction of the rotating shaft and are alternately distributed; The rotation speed detection component is used to transmit light signals to the multiple concave surfaces and the multiple convex surfaces, and receive the light signals reflected back by the multiple concave surfaces and the multiple convex surfaces, so as to detect the rotation speed of the color wheel based on the change of the light signals.

2. The color wheel device according to claim 1, characterized in that: The plurality of concave surfaces are part of the rotating shaft body, and the plurality of convex surfaces form a circular ring sleeved on the outer periphery of the rotating shaft.

3. The color wheel device according to claim 1, characterized in that: The plurality of concave surfaces and the plurality of convex surfaces together form a circular ring, and the circular ring is sleeved on the periphery of the rotating shaft.

4. The color wheel device according to claim 1, characterized in that: The wavelength conversion layer comprises at least two color partitions, each of the color partitions is used to emit light of a corresponding color, and a boundary line between two adjacent color partitions corresponds to an edge of the convex surface; Each of the color partitions corresponds to one of the concave surfaces and one of the convex surfaces.

5. The color wheel device according to claim 1, characterized in that: The rotation speed detection component includes a light sensor, a filter circuit connected to the light sensor, and a comparator circuit connected to the filter circuit; Wherein, the light sensor is used to transmit the light signal to the multiple concave surfaces and the multiple convex surfaces, and receive the light signal reflected back by the multiple concave surfaces and the multiple convex surfaces, so as to generate signals with different amplitudes and widths based on the reflected light signals, and output the signals with different amplitudes and widths to the comparator circuit through the filtering circuit, so as to output low-level pulses corresponding to the concave surfaces and high-level pulses corresponding to the convex surfaces through the comparator circuit.

6. The color wheel device according to claim 1, characterized in that: The multiple concave surfaces and the multiple convex surfaces are all in a fan-shaped shape, the fan-shaped radii corresponding to the multiple convex surfaces are all equal, and the fan-shaped radii and fan-shaped angles corresponding to the multiple concave surfaces are all equal.

7. The color wheel device according to claim 6, characterized in that: The plurality of convex surfaces include a first convex surface and at least one second convex surface; The sector angle corresponding to the first convex surface is not equal to the sector angle corresponding to the second convex surface; the sector angles corresponding to multiple second convex surfaces are equal.

8. The color wheel device according to claim 1, characterized in that: A black induction layer is arranged on the outer surface of the rotating shaft.

9. The color wheel device according to claim 8, characterized in that: The color wheel device further comprises a control device, and the control device is communicatively connected with the motor driving the rotating shaft to rotate and the rotation speed detection component.

10. A projection device, characterized in that: The invention comprises an excitation light source, a display component, a projection lens and a color wheel device as claimed in any one of claims 1 to 9.

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