Projection device and trigger correction method

Abstract

The projection device and trigger correction method provided in some embodiments of the present application obtain the distance data at the time of power-on and the distance data at the time of historical power-off. And based on the distance data at the time of power-on and the distance data at the time of historical power-off, the distance change data at the time of power-on relative to the time of historical power-off is calculated. If the distance change data is greater than the preset distance threshold, the optical machine is controlled to project the correction card image to the projection surface, so as to calibrate the area to be projected of the optical machine according to the correction card image taken by the camera, and the area to be projected is used to present the playback content. In this way, if the user has completed the calibration process after turning on the projection device, and turns it on again when the environment has not changed, the calibration process will not be triggered again. This avoids the situation where the projection device will automatically trigger the calibration process regardless of whether the environment has changed after the user turns on the projection device multiple times, thereby improving the user experience.

Description

Technical Field

[0001] The present application relates to the technical field of display devices, and in particular to a projection device and a trigger correction method. Background Art

[0002] A projection device is a display device that can project images or videos onto a screen. The projection device can project laser light of a specific color onto the screen through the refraction of an optical lens assembly to form a specific image. Due to the portability of the projection device, users can move it during the projection process to project images or videos in different directions.

[0003] Usually, in order to improve the projection effect of the projection device, the automatic keystone correction will be triggered after the projection device is turned on, that is, the output image will be refocused and corrected. However, if the user has completed the calibration process after turning on the device and turns it on again without changing the environment, the calibration process will be triggered again. In this way, after the user turns on the projection device multiple times and does not need to trigger the calibration process, the projection device will still automatically trigger the calibration process, reducing the user experience. Summary of the invention

[0004] In some embodiments of the present application, a projection device and a trigger correction method are provided to solve the problem that when the user turns on the projection device multiple times and does not need to trigger the correction process, the projection device will still automatically trigger the correction process, thereby reducing the user's usage experience.

[0005] On the one hand, some embodiments of the present application provide a projection device, including:

[0006] a distance sensor configured to collect distance data;

[0007] An optical machine is configured to project playback content onto a projection surface;

[0008] A camera configured to capture the image displayed on the projection surface;

[0009] The controller is configured as:

[0010] Get the distance data at the time of power-on and the distance data at the time of historical power-off;

[0011] According to the distance data at the power-on time and the distance data at the historical power-off time, the distance change data of the power-on time relative to the historical power-off time is calculated;

[0012] If the distance change data is greater than a preset distance threshold, the optical machine is controlled to project the correction card image onto the projection surface to correct the area to be projected of the optical machine according to the correction card image taken by the camera, and the area to be projected is used to present the playback content.

[0013] On the other hand, some embodiments of the present application further provide a trigger correction method, which is applied to a projection device, wherein the projection device includes a distance sensor, an optical machine, a camera, and a controller; the method specifically includes the following steps:

[0014] Get the distance data at the time of power-on and the distance data at the time of historical power-off;

[0015] According to the distance data at the power-on time and the distance data at the historical power-off time, the distance change data of the power-on time relative to the historical power-off time is calculated;

[0016] If the distance change data is greater than a preset distance threshold, the optical machine is controlled to project the correction card image onto the projection surface to correct the area to be projected of the optical machine according to the correction card image taken by the camera, and the area to be projected is used to present the playback content.

[0017] It can be seen from the above technical solutions that the projection device and trigger correction method provided in some embodiments of the present application obtain the distance data at the power-on time and the distance data at the historical power-off time. And according to the distance data at the power-on time and the distance data at the historical power-off time, the distance change data at the power-on time relative to the historical power-off time is calculated. If the distance change data is greater than the preset distance threshold, the optical machine is controlled to project the correction card image to the projection surface, so as to correct the area to be projected of the optical machine according to the correction card image taken by the camera, and the area to be projected is used to present the playback content. In this way, if the user has completed the correction process after turning on the projection device, and turns it on again when the environment has not changed, the correction process will not be triggered again. Avoid the situation where the projection device will automatically trigger the correction process regardless of whether the environment changes after the user turns on the projection device multiple times, thereby improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 This is a schematic diagram of the projection placement state of the projection device in the embodiment of the present application;

[0020] Figure 2 This is a schematic diagram of the optical path of the projection device in the embodiment of the present application;

[0021] Figure 3 This is a schematic diagram of the circuit architecture of the projection device in the embodiment of the present application;

[0022] Figure 4 This is a schematic diagram of the structure of a projection device in an embodiment of the present application;

[0023] Figure 5 This is a schematic diagram of the lens structure of the projection device in the embodiment of the present application;

[0024] Figure 6 This is a schematic diagram of the distance sensor and camera structure of the projection device in the embodiment of the present application;

[0025] Figure 7 A schematic diagram of a system framework for realizing display control of a projection device in an embodiment of the present application;

[0026] Figure 8 This is a schematic diagram of the case where the position of the projection device is changed in an embodiment of the present application;

[0027] Fig. 9 This is a schematic diagram of a projection device triggering image correction based on distance data in an embodiment of the present application;

[0028] Fig.10 It is a schematic diagram of a projection device triggering image correction based on acceleration data in an embodiment of the present application. DETAILED DESCRIPTION

[0029] In order to make the purpose and implementation method of the present application clearer, the exemplary implementation method of the present application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0030] It should be noted that the brief description of terms in this application is only for the convenience of understanding the embodiments described below, and is not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their ordinary and common meanings.

[0031] The terms "first", "second", "third", etc. in the specification and claims of this application and the above drawings are used to distinguish similar or similar objects or entities, and do not necessarily mean to limit a specific order or sequence, unless otherwise noted. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances.

[0032] The terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover but not exclude inclusion, for example, a product or device comprising a list of components is not necessarily limited to all the components expressly listed but may include other components not expressly listed or inherent to such product or device.

[0033] The term "module" refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and / or software code that is capable of performing the functions associated with that element.

[0034] The embodiments of the present application can be applied to various types of projection devices. The following will take the projection device as an example to explain the projection device and the automatic focusing method.

[0035] Projection equipment is a device that can project images or videos onto a screen. Projection equipment can be connected to computers, broadcasting networks, the Internet, VCD (Video Compact Disc), DVD (Digital Versatile Disc Recordable), game consoles, DV, etc. through different interfaces to play corresponding video signals. Projection equipment is widely used in homes, offices, schools, and entertainment venues.

[0036] Figure 1 The figure shows a schematic diagram of the placement state of a projection device according to an embodiment of the present application. Figure 2 A schematic diagram of the optical path of a projection device according to an embodiment of the present application is shown.

[0037] In some embodiments, reference Figure 1-Figure 2 A projection device provided in the present application includes a projection screen 1 and a projection device 2. The projection screen 1 is fixed at a first position, and the projection device 2 is placed at a second position, so that the image projected by the projection device 2 matches the projection screen 1. The projection device 2 includes a laser light source 100, an optical machine 200, a lens 300, and a projection medium. The laser light source 100 provides illumination for the optical machine 200, and the optical machine 200 modulates the light source beam and outputs it to the lens 300 for imaging, which is projected onto the projection medium to form a projection surface 400.

[0038] In some embodiments, the laser light source 100 of the projection device 2 includes a laser assembly 110 and an optical lens assembly 120. The light beam emitted by the laser assembly 110 can pass through the optical lens assembly 120 to provide lighting for the optical machine. For example, the optical lens assembly 120 requires a higher level of environmental cleanliness and airtightness; while the chamber in which the laser assembly is installed can be sealed with a lower level of dustproofness to reduce the sealing cost.

[0039] In some embodiments, the light engine 200 of the projection device 2 may be implemented as a blue light engine, a green light engine, a red light engine, and may also include a heat dissipation system, a circuit control system, etc. It should be noted that in some embodiments, the light emitting component of the projection device 2 may also be implemented by an LED light source.

[0040] Figure 3A schematic diagram of the circuit architecture of a projection device according to an embodiment of the present application is shown. In some embodiments, the projection device 2 may include a display control circuit 10, a laser light source 20, at least one laser driving component 30, and at least one brightness sensor 40. The laser light source 20 may include at least one laser corresponding to the at least one laser driving component 30. The at least one refers to one or more, and the multiple refers to two or more.

[0041] Based on the circuit architecture, the projection device 2 can achieve adaptive adjustment. For example, by setting a brightness sensor 40 in the light output path of the laser light source 20, the brightness sensor 40 can detect a first brightness value of the laser light source and send the first brightness value to the display control circuit 10.

[0042] The display control circuit 10 can obtain the second brightness value corresponding to the driving current of each laser, and when it is determined that the difference between the second brightness value of the laser and the first brightness value of the laser is greater than the difference threshold, it is determined that a COD fault occurs in the laser; the display control circuit can adjust the current control signal of the laser driving component corresponding to the laser until the difference is less than or equal to the difference threshold, thereby eliminating the COD fault of the blue laser; the projection device 2 can eliminate the COD fault of the laser in time, reduce the damage rate of the laser, and improve the image display effect of the projection device 2.

[0043] Figure 4 A schematic structural diagram of a projection device according to an embodiment of the present application is shown.

[0044] In some embodiments, the laser light source 20 in the projection device 2 may include independently arranged blue laser 201, red laser 202 and green laser 203. The projection device 2 may also be called a three-color projection device. The blue laser 201, the red laser 202 and the green laser 203 are all modular lightweight (Mirai Console Loader, MCL) packaged lasers, which are small in size and conducive to the compact arrangement of the optical path.

[0045] In some embodiments, the controller includes at least one of a central processing unit (CPU), a video processor, an audio processor, a graphics processing unit (GPU), a RAM Random Access Memory (RAM), a ROM (Read-Only Memory, ROM), a first interface to an nth interface for input / output, a communication bus (Bus), etc.

[0046] In some embodiments, after the projection device 2 is started, it can directly enter the display interface of the last selected signal source, or the signal source selection interface, where the signal source can be a preset video on demand program, or at least one of an HDMI interface, a live TV interface, etc. After the user selects a different signal source, the projector can display the content obtained from different signal sources.

[0047] In some embodiments, the projection device 2 may be equipped with a camera, which is used to work in conjunction with the projection device 2 to achieve adjustment and control of the projection process. For example, the camera configured by the projection device 2 may be specifically implemented as a 3D camera or a binocular camera; when the camera is implemented as a binocular camera, it specifically includes a left camera and a right camera; the binocular camera may obtain the image and playback content presented by the screen corresponding to the projection device 2, that is, the projection surface 400, and the image or playback content is projected by the built-in optical machine of the projection device 2.

[0048] The camera can be used to capture the image displayed on the projection surface 400, and can be a camera. The camera can include a lens assembly, in which a photosensitive element and a lens are provided. The lens refracts light through a plurality of lenses, so that the light of the image of the scene can be irradiated on the photosensitive element. The photosensitive element can be selected based on the detection principle of a charge coupled device or a complementary metal oxide semiconductor according to the specifications of the camera, and converts the light signal into an electrical signal through a photosensitive material, and outputs the converted electrical signal into image data.

[0049] Figure 5 Schematic diagram of the lens structure of the projection device 2 in some embodiments is shown. In order to support the automatic focusing process of the projection device 2, as shown in FIG. Figure 5 As shown, the lens 300 of the projection device 2 may further include an optical component 310 and a drive motor 320. The optical component 310 is a lens group composed of one or more lenses, which can refract the light emitted by the optical machine 200 so that the light emitted by the optical machine 200 can be transmitted to the projection surface 400 to form a transmission content image.

[0050] The optical assembly 310 may include a lens barrel and a plurality of lenses disposed in the lens barrel. Depending on whether the position of the lens can be moved, the lens in the optical assembly 310 may be divided into a movable lens 311 and a fixed lens 312. By changing the position of the movable lens 311 and adjusting the distance between the movable lens 311 and the fixed lens 312, the overall focal length of the optical assembly 310 may be changed. Therefore, the driving motor 320 may drive the movable lens 311 to move its position by connecting to the movable lens 311 in the optical assembly 310, thereby realizing an automatic focusing function.

[0051] It should be noted that the focusing process described in some embodiments of the present application refers to changing the position of the movable lens 311 by driving the motor 320, thereby adjusting the distance between the movable lens 311 and the fixed lens 312, that is, adjusting the image plane position. Therefore, the imaging principle of the lens combination in the optical component 310, the adjustment of the focal length is actually adjusting the image distance, but in terms of the overall structure of the optical component 310, adjusting the position of the movable lens 311 is equivalent to adjusting the overall focal length of the optical component 310.

[0052] When the distance between the projection device 2 and the projection surface 400 is different, the lens of the projection device 2 needs to adjust different focal lengths to project a clear image on the projection surface 400. During the projection process, the distance between the projection device 2 and the projection surface 400 will require different focal lengths depending on the placement of the user. Therefore, in order to adapt to different usage scenarios, the projection device 2 needs to adjust the focal length of the optical component 310.

[0053] Figure 6 Schematic diagram of distance sensor and camera structure in some embodiments is shown. Figure 6 As shown, the projection device 2 may also have a built-in or external camera 700, and the camera 700 may capture the image projected by the projection device 2 to obtain the projection content image. The projection device 2 then performs a clarity detection on the projection content image to determine whether the current lens focal length is appropriate, and adjusts the focal length if it is not appropriate. When automatically focusing based on the projection content image captured by the camera 700, the projection device 2 may continuously adjust the lens position and take pictures, and find the focus position by comparing the clarity of the front and back position pictures, thereby adjusting the movable lens 311 in the optical component to a suitable position. For example, the controller 500 may first control the drive motor 320 to gradually move the focus starting position of the movable lens 311 to the focus end position, and continuously obtain the projection content image through the camera 700 during this period. Then, by performing a clarity detection on multiple projection content images, the position with the highest clarity is determined, and finally the drive motor 320 is controlled to adjust the movable lens 311 from the focus terminal to the position with the highest clarity to complete the automatic focusing.

[0054] For the automatic focusing process, after obtaining the automatic focusing instruction, the controller of the projection device can respond to the automatic focusing instruction and obtain the interval distance through the distance sensor 600. Among them, the distance sensor 600 can be a sensor device based on the time of flight (Time of Flight, TOF) principle, such as a laser radar, an infrared radar, etc. that can detect the target distance. The distance sensor 600 can be set at the position of the optical machine 200, including a signal transmitter and a receiver. In the process of detecting the interval distance, the transmitter of the distance sensor 600 can transmit a wireless signal in the direction of the projection surface 400. After the wireless signal contacts the projection surface 400, it will be reflected back to the receiving end of the distance sensor 600, so that the signal flight time is calculated according to the time when the transmitter sends the signal and the time when the receiver receives the signal. Combined with the flight speed, the actual flight distance of the wireless signal can be obtained, and then the interval distance between the projection surface 400 and the optical machine 200 is calculated.

[0055] Figure 7 A schematic diagram of a system framework for realizing display control of a projection device according to an embodiment of the present application is shown.

[0056] In some embodiments, the projection device 2 has the characteristics of a telephoto micro-projector, and its controller can control the display of the projection light image through a preset algorithm to achieve functions such as automatic trapezoidal correction of the display screen, automatic screen entry, automatic obstacle avoidance, automatic focusing, and anti-eye-shooting.

[0057] In some embodiments, the projection device 2 is configured with a gyroscope sensor; when the device is moving, the gyroscope sensor can sense the position movement and actively collect movement data; then the collected data is sent to the application service layer through the system framework layer to support the application data required during the user interface interaction and application interaction process. The collected data can also be used for data calls by the controller in the algorithm service implementation.

[0058] In some embodiments, the projection device 2 is configured with a time-of-flight sensor. After the time-of-flight sensor collects corresponding data, the data will be sent to the corresponding time-of-flight service of the service layer; after the above-mentioned time-of-flight service obtains the data, it will send the collected data to the application service layer through the process communication framework, and the data will be used for interactive use such as controller data calls, user interfaces, and program applications.

[0059] In some embodiments, the projection device 2 is configured with a camera 700 for capturing images, and the camera 700 can be implemented as a binocular camera, a depth camera, a 3D camera, etc.; the data captured by the camera 700 will be sent to the camera service, and then the camera service will send the captured image data to the process communication framework and / or the projection device correction service; the projection device correction service can receive the camera 700 capture data sent by the camera service, and the controller can call the corresponding control algorithm in the algorithm library according to the different functions to be implemented.

[0060] In some embodiments, data is interacted with the application service through the process communication framework, and then the calculation results are fed back to the correction service through the process communication framework; the correction service sends the obtained calculation results to the projection device 2 operating system to generate control signals, and sends the control signals to the optical machine control driver to control the optical machine working conditions and realize automatic correction of the displayed image.

[0061] In some embodiments, when an image correction instruction is detected, the projection device 2 can correct the projected image. For the correction of the projected image, an association relationship between the distance, the horizontal angle, and the offset angle can be created in advance. Then the controller of the projection device 2 obtains the current distance from the optical machine 200 to the projection surface 400, and determines the angle between the optical machine 200 and the projection surface 400 at this moment in combination with the associated relationship to achieve projection image correction. Among them, the angle is specifically implemented as the angle between the central axis of the optical machine 200 and the projection surface 400.

[0062] In some embodiments, the projection device 2 automatically completes the calibration and refocuses, and the controller will detect whether the automatic focus function is turned on; when the automatic focus function is not turned on, the controller will end the automatic focus service; when the automatic focus function is turned on, the projection device 2 will obtain the detection distance of the time-of-flight sensor through the middleware for calculation.

[0063] The controller queries the preset mapping table according to the acquired distance to obtain the focal length of the projection device 2; then the middleware sets the acquired focal length to the optical machine 200 of the projection device 2; after the optical machine 200 emits laser with the above focal length, the camera will execute the photo command; the controller determines whether the focusing of the projection device 2 is completed according to the acquired captured image and evaluation function.

[0064] If the judgment result meets the preset completion conditions, the control of the automatic focusing process ends; if the judgment result does not meet the preset completion conditions, the middleware will fine-tune the focal length parameters of the optical machine 200, for example, the focal length can be gradually fine-tuned with a preset step length, and the adjusted focal length parameters will be set to the optical machine 200 again; thereby achieving repeated photo taking and clarity evaluation steps, and finally finding the optimal focal length through clarity comparison to complete automatic focusing.

[0065] In some embodiments, when the user turns on the projection device 2, the projection device 2 can project the content pre-set by the user onto the projection surface 400, which can be a wall or a curtain, and the projection image can be displayed on the projection surface 400 for the user to watch. However, when the user places the projection device 2 in an improper position, the projection device 2 and the projection surface 400 may not be perpendicular, causing the projected image to be displayed as a trapezoidal image or other deformed image. Or during use, the user touches the projection device 2, causing the position of the projection device 2 to change, and its projection angle and the distance to the projection surface 400 change, thereby causing the projection image to be deformed, and the projection image will also be displayed as a trapezoidal image or other deformed image. For the above situation, it is necessary to perform image correction processing on the projection device 2 so that the projection device 2 can project an image of a standard shape on the projection surface 400 for the user to watch.

[0066] Figure 8 Schematic diagrams of some embodiments when the position of the projection device changes are shown. The projection device 2 is initially at position A and can project onto a suitable projection area, which is rectangular and can usually completely and accurately cover the corresponding rectangular screen. When the projection device 2 moves from position A to position B, a deformed projection image is often generated, such as a trapezoidal image, causing the projection image to not match the rectangular screen.

[0067] Usually, the projection device 2 has an image correction function. When the projection image projected by the projection device 2 on the projection surface 400 has a deformed image such as a trapezoid, the projection device 2 can automatically correct the projection image to obtain an image of a regular shape, which can be a rectangular image, thereby achieving image correction.

[0068] Specifically, it can be configured that when receiving the image correction instruction, the projection device 2 can start the image correction function to correct the projected image. The image correction instruction refers to a control instruction for triggering the projection device 2 to automatically perform image correction.

[0069] In some embodiments, the image correction instruction may be an instruction actively input by the user. For example, after the power of the projection device 2 is turned on, the projection device 2 may project an image on the projection surface 400. At this time, the user may press the image correction switch pre-set in the projection device 2, or the image correction button on the remote control of the projection device 2, so that the projection device 2 turns on the image correction function and automatically performs image correction on the projected image.

[0070] In some embodiments, the image correction instruction may also be automatically generated according to a control program built into the projection device 2 .

[0071] The projection device 2 may actively generate the image correction instruction after being powered on. For example, when the projection device 2 detects the first video signal input after being powered on, the image correction instruction may be generated, thereby triggering the image correction function.

[0072] Alternatively, the projection device 2 may generate an image correction instruction by itself during operation. Considering that the user may actively move the projection device 2 or accidentally touch the projection device 2 during the use of the projection device 2, causing the placement posture or setting position of the projection device 2 to change, the projected image may also become a trapezoidal image. At this time, in order to ensure the user's viewing experience, the projection device 2 can automatically perform image correction.

[0073] Specifically, the projection device 2 can detect its own situation in real time. When the projection device 2 detects that its own placement posture or setting position has changed, it can generate an image correction instruction to trigger the image correction function.

[0074] Usually, when the projection device 2 detects the first video signal input after power-on, an image correction instruction can be generated, thereby automatically triggering the image correction function, that is, executing the correction process. However, if the user has completed the correction process after powering on, and when the environment does not change and the projection device 2 is turned on again, the projection device 2 will still trigger the correction process again. Exemplary, under normal circumstances, the projection device 2 controls the optical machine 200 to project the playback content in the projection area, which has completed the image correction. At this time, the user turns off the projection device 2 and moves the position (such as from the living room to the bedroom). After starting the projection device 2 again, when the projection device 2 detects the first video signal input after powering on, an image correction instruction can be generated, thereby automatically triggering the image correction function, that is, executing the graphic correction process. However, if the user does not move the position after turning off the projection device 2, at this time, the projection device 2 of the present application can be used in the current scene to avoid the situation where the image correction is automatically triggered by the power on and off of the projection device 2 after the position has not been moved, thereby improving the user's experience.

[0075] In some embodiments, the projection device 2 may include an optical machine 200, a light source, an acceleration sensor, a distance sensor 600, a camera 700, and a controller. The optical machine 200 is used to project the playback content preset by the user onto the projection surface 400, and the projection surface 400 may be a wall or a curtain. The controller may perform image correction on the projection device 2 through the image captured by the camera 700. The distance sensor 600 is used to collect distance data. The light source is used to provide lighting for the optical machine 200. The acceleration sensor is used to determine whether the projection device 2 moves. This is to solve the problem that the projection device 2 will automatically trigger the correction process in the scenario where the user turns on the projection device 2 multiple times and does not need to trigger the correction process.

[0076] It should be noted that when the projection device 2 receives the image correction instruction, the projection device 2 can trigger the image correction function. Furthermore, the method for generating the image correction instruction includes but is not limited to the user selecting a preset shift automatic correction switch to generate it, and can also be automatically generated by the projection device 2 based on detecting the first video signal input after power-on. Therefore, the embodiment of the present application will be specifically described with the shift automatic correction switch being in the on state. It can be understood that when the shift automatic correction switch is in the on state, the projection device 2 detects the first video signal input after power-on and automatically turns on the image correction function. When the shift automatic correction switch is in the off state, the projection device 2 does not turn on the image correction function.

[0077] The following combination Fig. 9 The triggered image correction process provided in the embodiment of the present application is explained.

[0078] In some embodiments, Fig. 9 FIG. 2 shows a schematic diagram of a projection device triggering image correction in an embodiment of the present application. Fig. 9 , the controller obtains the distance data at the power-on time and the distance data at the historical power-off time. According to the distance data at the power-on time and the distance data at the historical power-off time. Among them, the power-on time is the starting time of the current working process of the projection device, and the historical power-off time is the ending time of the previous working process of the projection device. The distance change data at the power-on time relative to the historical power-off time is calculated. If the distance change data is greater than the preset distance threshold, the optical machine 200 is controlled to project the correction card image to the projection surface, so as to correct the area to be projected of the optical machine 200 according to the correction card image taken by the camera, and the area to be projected is used to present the playback content. In this way, by comparing the distance data at the current power-on time with the distance data at the historical power-off time, the distance change data at the power-on time relative to the historical power-off time is obtained. When the distance change data is greater than the preset distance threshold, it means that the user has changed the placement position of the projection device after the historical power-off time. Then, the controller automatically triggers the image correction process.

[0079] It should be noted that, in the embodiment of the present application, the power-on time is the start time of the current working process of the projection device 2, and the historical power-off time is the end time of the previous working process of the projection device 2. In other words, the historical power-off time is the most recent power-off time before the current power-on time. In this way, by comparing the distance data between the current power-on time and the most recent power-off time before the current power-on time, it is ensured that the power-on and power-off of the projection device 2 after it has not moved does not automatically trigger the image correction process.

[0080] In order to trigger the image correction process more accurately, before calculating the distance change data at the power-on time relative to the historical power-off time, the controller is further configured to: parse the power-on distance value in the distance data at the power-on time, and parse the historical power-off distance value in the distance data at the historical power-off time. If the power-on distance value and the historical power-off distance value are within the effective distance range, the process of calculating the distance change data is executed; the effective distance range is set according to the setting position of the distance sensor 600 and the projection surface 400.

[0081] Exemplarily, before calculating the distance change data, the power-on distance value and the historical power-off distance value need to be judged. For example, the effective distance range is 0-3.5 meters. The power-on distance value is 3 meters, and the historical power-off distance value is 2.4 meters. At this time, the power-on distance value of 3 meters is within the effective distance range, which means that the power-on distance value is valid. Similarly, the historical power-off distance value of 2.4 meters is also within the effective distance range, which means that the historical power-off distance value is valid. On the contrary, if the power-on distance value and the historical power-off distance value are not within the effective distance range, the controller re-triggers the process of obtaining distance data. It should be noted that the controller can perform the process of obtaining multiple sets of distance data at different times, for example, real-time acquisition of distance data at the current power-on time, as well as distance data before the historical power-off time and / or distance data at the time of the most recent image correction completed at the historical power-off time. Furthermore, it is convenient to more accurately determine whether the projection device 2 has actually changed its position based on multiple sets of distance data.

[0082] In some embodiments, in the step of executing the calculation of distance change data, the controller is further configured to: subtract the historical shutdown distance value from the startup distance value, and extract the absolute value of the difference to generate a distance difference; calculate the ratio of the distance difference to the startup distance value; if the ratio is greater than a preset ratio threshold, execute the subsequent process of projecting the correction card onto the projection surface 400.

[0083] Exemplarily, the preset proportional threshold is 0.05. Continuing with the above example, the power-on distance value of 3 meters is subtracted from the historical power-off distance value of 2.4 meters, that is, the difference is 0.6 meters. The absolute value of the difference is extracted, that is, the distance difference is 0.6 meters, and the ratio of the distance difference to the power-on distance value is calculated as 0.6 / 3=0.2. Furthermore, the ratio of 0.5 is greater than the preset proportional threshold of 0.05, indicating that the position of the projection device at the current power-on moment has changed relative to the position of the projection device at the historical power-off moment, and the controller automatically triggers the graphics correction process. It should be noted that the embodiment of the present application does not impose a numerical limitation on the preset proportional threshold. Those skilled in the art can determine the value of the preset acceleration threshold according to actual needs, such as 0.01, 0.02, 0.03, etc. These designs do not exceed the protection scope of the embodiment of the present application.

[0084] In some embodiments, the controller is configured to: obtain the distance data at the current moment, and parse the current distance value in the distance data. If the current distance value is within the valid distance range, the data tag corresponding to the distance data at the current moment is assigned a first state identifier, and the first state identifier is used to indicate that the current distance value is a valid distance. If the current distance value is not within the valid distance range, the data tag corresponding to the distance data at the current moment is assigned a second state identifier, and the second state identifier is used to indicate that the current distance value is an invalid distance.

[0085] Exemplarily, if the current distance value is within the valid distance range, the data tag corresponding to the distance data at the current moment is assigned as a first state identifier, such as systemproperty is 1. If the current distance value is not within the valid distance range, the data tag corresponding to the distance data at the current moment is assigned as a second state identifier, such as systemproperty is -2. It should be noted that during the operation of the projection device 2, the controller can obtain the distance data in real time and assign the data tag corresponding to the distance data. The embodiment of the present application does not limit the time of assigning the data tag. For example, the projection device 2 can assign the data tag when it is turned on and automatically completes the image correction, and can also assign the data tag when it is turned on and receives the image correction instruction input by the user. In this way, the controller can directly determine whether the distance data is within the valid distance range based on the value corresponding to the data tag.

[0086] In some embodiments, when the controller performs image correction, the state of the projection device 2 must be guaranteed to be static. Therefore, through the acceleration sensor configured by the projection device 2, the controller receives monitoring data from the acceleration sensor to determine whether the projection device 2 moves. After determining that the projection device 2 moves, the controller can generate an image correction instruction and start the image correction function.

[0087] Usually, during the movement of the projection device 2, the projection device 2 obtains acceleration data in real time based on the acceleration sensor (gyroscope sensor), and determines whether the projection device 2 moves by the change of the acceleration data. If the projection device 2 moves, the image correction function is started when the projection device 2 is in a stationary state.

[0088] In some implementations, see Fig.10, the controller is configured to: obtain acceleration data at the startup time and acceleration data at the historical shutdown time; calculate acceleration change data according to the acceleration data at the startup time and the acceleration data at the historical shutdown time; if the acceleration change data is less than a preset acceleration threshold, execute the step of projecting the calibration card to the projection surface 400. The startup time is the start time of the current working process of the projection device 2, and the historical shutdown time is the end time of the previous working process of the projection device 2.

[0089] In the above process of determining whether the acceleration change data is less than the preset acceleration threshold, the controller is configured to: analyze the movement angle of the projection device 2 in the three-axis coordinate directions in the acceleration change data; if the movement angles in the three-axis coordinate directions are all less than the preset acceleration threshold, determine that the acceleration change data is less than the preset acceleration threshold.

[0090] Exemplarily, the controller monitors and receives acceleration data collected by the gyroscope sensor, i.e., the acceleration sensor, at the startup time and the historical shutdown time in real time. The acceleration data includes acceleration data on three axis coordinates (X, Y, and Z axis). Since the acceleration data represents the acceleration data collected in the three axis coordinate directions, when the acceleration data on one of the axes changes, it indicates that the projection device 2 has shifted in the axis coordinate direction. Therefore, it is possible to determine whether the projection device 2 has moved by judging the data in the three axis directions of the acceleration data. Next, the acceleration data in the three axis coordinate directions are converted into angular velocity data, and the moving angle of the projection device 2 in the three axis coordinate directions is determined by the angular velocity data.

[0091] In this way, the controller obtains the acceleration data collected at the startup moment and the acceleration data collected at the historical shutdown moment, and calculates the movement angle of the projection device 2 in the three axis coordinate directions through the acceleration change data at the startup moment relative to the historical shutdown moment. If the movement angles in the three axis coordinate directions are all less than the preset acceleration thresholds, it is determined that the projection device 2 is in a stationary state, and the optical machine 200 can be controlled to project the correction chart to the projection surface 400 to trigger the image correction process. It should be noted that the embodiment of the present application does not impose a numerical limitation on the preset acceleration threshold, and those skilled in the art can determine the value of the preset acceleration threshold according to actual needs, such as 0.1, 0.2, 0.3, etc., and these designs do not exceed the protection scope of the embodiments of the present application.

[0092] It should be noted that since the acceleration data is collected in real time by the gyroscope sensor and sent to the controller, the process of acquiring multiple groups of acceleration data at different times can be performed multiple times to more accurately determine whether the projection device 2 is truly in a stationary state. The embodiment of the present application does not specifically limit the number of executions of the acquisition and judgment process, and can be set multiple times according to the device state corresponding to the specific projection device 2, and all are within the protection scope of the embodiment of the present application.

[0093] In an implementable manner, the image correction process specifically includes: the controller controls the optical machine 200 to project the correction card to the projection surface 400. And the area to be projected in the projection surface 400 is determined according to the image of the correction card captured by the camera 700. Among them, the process of determining the area to be projected is the process of calibrating the projection area of ​​the optical machine 200. Finally, the playback content is projected to the area to be projected. Among them, the correction card includes a correction white card and a correction picture card.

[0094] In some embodiments, in the step of calibrating the area to be projected of the optical machine 200 according to the calibration card image taken by the camera 700, the controller is further configured to: determine the image position of the calibration feature point in the calibration card image, and obtain the projection relationship according to the image position, wherein the projection relationship is the mapping relationship between the playback content projected by the optical machine 200 and the projection surface 400. Finally, the area to be projected is calibrated according to the projection relationship.

[0095] In the above step of acquiring the projection relationship according to the image position, the controller is further configured to: acquire the camera coordinates of the correction feature point in the camera coordinate system according to the image position. Convert the camera coordinates into the optomechanical coordinates of the correction feature point in the optomechanical coordinate system. Acquire the homography matrix of the projection surface 400 in the optomechanical coordinate system according to the optomechanical coordinates, and the homography matrix is ​​used to characterize the projection relationship.

[0096] In some embodiments, after the optical machine 200 projects the calibration chart onto the projection surface 400, the controller may control the camera 700 to photograph the calibration chart to obtain a calibration chart image to acquire the positions of the calibration feature points.

[0097] The controller can perform image recognition processing on the calibration card image to obtain the first position of the calibration feature point in the calibration image. In the embodiment of the present application, the first position refers to: the coordinate information of the calibration feature point in the image coordinate system corresponding to the calibration card image.

[0098] The image coordinate system refers to a coordinate system with the center of the image as the coordinate origin and the X and Y axes parallel to the sides of the image. The image coordinate system in the embodiment of the present application can be set as follows: for the projection area preset by the user, the center point of the projection area can be set as the origin, the horizontal direction is the X axis, and the vertical direction is the Y axis. The image coordinate system can be set in advance according to the preset projection area.

[0099] The coordinate information of the correction feature points in the correction image can be determined according to the image coordinate system.

[0100] In the embodiment of the present application, the camera coordinate system is specifically: a direct coordinate system of space is established with the light point of the camera 700 as the center, the optical axis as the Z axis, and the XOY plane parallel to the projection plane.

[0101] In some embodiments, after acquiring the coordinate information of the calibration feature point in the camera coordinate system of the camera 700 , the controller may convert the coordinate information into the coordinates of the calibration feature point in the optomechanical coordinate system.

[0102] In one achievable manner, the projection device 2 can obtain the angular relationship between the first correction coordinate and the second correction coordinate through a preset correction algorithm. The projection relationship refers to the projection relationship of the projection device 2 projecting the image onto the projection surface, specifically the mapping relationship between the playback content projected by the optical machine of the projection device 2 and the projection surface.

[0103] In the embodiment of the present application, the optical-mechanical coordinate system is specifically: a direct coordinate system of space is established with the optical spot of the optical machine as the center, the optical axis as the Z axis, and the XOY plane parallel to the projection plane. It should be noted that the optical-mechanical coordinate system and the camera coordinate system can be converted to each other, so the coordinates of the calibration feature points in the camera coordinate system can be converted to the coordinates in the optical-mechanical coordinate system.

[0104] In some embodiments, after the coordinates of the calibration feature points in the optomechanical coordinate system are acquired, the projection surface equation of the projection surface in the optomechanical coordinate system may be determined.

[0105] It should be noted that since the coordinate information of at least three points is required to determine the position information of a plane, the controller can obtain the first positions of at least three calibration feature points in the calibration card image, and determine the coordinate information in the camera coordinate system according to the first positions of these calibration feature points. The coordinate information in the camera coordinate system can be further converted into the coordinate information in the optical-mechanical coordinate system.

[0106] After determining the coordinate information of at least three correction feature points in the optical machine coordinate system, the controller can fit the coordinates of these correction feature points to obtain the homography matrix of the projection surface in the optical machine coordinate system. In this way, the homography matrix, i.e., the transformation matrix, can represent the mapping relationship between the playback content projected by the optical machine 200 and the projection surface.

[0107] In some embodiments, the area to be projected may be a pre-set projection area, or a fixed projection area set by the user, and the projection device 2 is placed at a position to achieve the best projection effect during operation, and then projected onto the display area on the projection surface.

[0108] The position information of the preset projection area in the projection surface is determined, so the position information of the projection area in the projection surface, that is, in the image coordinate system, can be directly determined. The projection area is generally set as a rectangular area, and the position information of the rectangular area can be represented by the coordinates of the four vertices of the rectangular area. The coordinates of a vertex in the rectangular area are set to (x, y). Since the projection surface is the XOY plane of the world coordinate system, the origin is the center point of the preset projection area. Therefore, the vertex coordinates are represented as (x, y, z) in the world coordinate system.

[0109] The controller can convert the coordinate representation in the world coordinate system into the coordinate representation in the optical machine coordinate system according to the projection relationship, so the vertex coordinates in the world coordinate system are represented as (x′, y′, z′). The controller can further obtain the coordinates of all vertices of the preset projection area in the optical machine coordinate system, thereby determining the position information of the projection area in the optical machine coordinate system. The controller can control the optical machine 200 to project the playback content to the position information, thereby achieving image correction.

[0110] In some embodiments, during the image correction process of the projection device 2, the camera 700 captures the image in real time. At the same time, if a person is detected to enter the image, the projection device 2 will automatically trigger the eye protection mode. In this way, in order to reduce the damage of the light source to the human eye, the projection device 2 can change the image brightness by adjusting the light source brightness, thereby achieving the effect of protecting the human eye.

[0111] It can be seen from the above technical solution that the projection device 2 provided in some embodiments of the present application obtains the distance data at the power-on time and the distance data at the historical power-off time through the controller. And according to the distance data at the power-on time and the distance data at the historical power-off time, the distance change data at the power-on time relative to the historical power-off time is calculated. If the distance change data is greater than the preset distance threshold, the optical machine 200 is controlled to project the correction card image to the projection surface, so as to calibrate the area to be projected of the optical machine 200 according to the correction card image taken by the camera 700, and the area to be projected is used to present the playback content. In this way, if the user has completed the calibration process after turning on the projection device 2, and turns it on again when the environment has not changed, the calibration process will not be triggered again. It avoids the situation where the projection device 2 will automatically trigger the calibration process regardless of whether the environment changes after the user turns on the projection device 2 multiple times, thereby improving the user experience.

[0112] In some embodiments, the present application further provides a trigger correction method, which is applied to a projection device 2, wherein the projection device 2 includes a distance sensor 600, an optical machine 200, a camera 700, and a controller; the method specifically includes the following steps:

[0113] Acquire the distance data at the power-on time and the distance data at the historical power-off time; calculate the distance change data at the power-on time relative to the historical power-off time based on the distance data at the power-on time and the distance data at the historical power-off time; if the distance change data is greater than the preset distance threshold, control the optical machine to project the correction card image to the projection surface, so as to calibrate the area to be projected of the optical machine according to the correction card image taken by the camera, and the area to be projected is used to present the playback content.

[0114] In some embodiments, the method includes: parsing the power-on distance value in the distance data at the power-on time, and parsing the historical power-off distance value in the distance data at the historical power-off time; if the power-on distance value and the historical power-off distance value are within the effective distance range, executing the process of calculating the distance change data; the effective distance range is set according to the setting position of the distance sensor and the projection surface.

[0115] In some embodiments, the method includes: in the step of calculating the distance change data, subtracting the historical shutdown distance value from the startup distance value, and extracting the absolute value of the difference to generate a distance difference; calculating the ratio of the distance difference to the startup distance value; if the ratio is greater than a preset ratio threshold, executing the process of projecting the correction card onto the projection surface.

[0116] In some embodiments, the method includes: obtaining distance data at the current moment; parsing the current distance value in the distance data; if the current distance value is within the valid distance range, assigning the data tag corresponding to the distance data at the current moment to a first state identifier, and the first state identifier is used to characterize that the current distance value is a valid distance; if the current distance value is not within the valid distance range, assigning the data tag corresponding to the distance data at the current moment to a second state identifier, and the second state identifier is used to characterize that the current distance value is an invalid distance.

[0117] In some embodiments, an acceleration sensor is also included, and the acceleration sensor is configured to collect acceleration data. The method includes: before the step of controlling the optical machine to project the correction card to the projection surface, obtaining the acceleration data at the power-on time and the acceleration data at the historical power-off time; according to the acceleration data at the power-on time and the acceleration data at the historical power-off time, calculating the acceleration change data; if the acceleration change data is less than the preset acceleration threshold, executing the step of projecting the correction card to the projection surface.

[0118] In some embodiments, the method includes: parsing the movement angle of the projection device in the three axis coordinate directions in the acceleration change data; if the movement angles in the three axis coordinate directions are all less than the preset acceleration threshold, determining that the acceleration change data is less than the preset acceleration threshold.

[0119] In some embodiments, the correction card includes correction feature points; the method includes: in the step of calibrating the area to be projected of the optical machine according to the correction card image taken by the camera, determining the image position of the correction feature point in the correction card image, and obtaining the projection relationship according to the image position, wherein the projection relationship is the mapping relationship between the playback content projected by the optical machine and the projection surface; and correcting the area to be projected according to the projection relationship.

[0120] In some embodiments, the method includes: in the step of acquiring the projection relationship according to the image position, acquiring the camera coordinates of the correction feature point in the camera coordinate system according to the image position; converting the camera coordinates into the optomechanical coordinates of the correction feature point in the optomechanical coordinate system; acquiring the homography matrix of the projection surface in the optomechanical coordinate system according to the optomechanical coordinates, and the homography matrix is ​​used to characterize the projection relationship.

[0121] The same and similar parts between the various embodiments in this specification can be referenced to each other and will not be described again here.

[0122] Those skilled in the art can clearly understand that the technology in the embodiments of the present invention can be implemented by means of software plus a necessary general hardware platform. Based on this understanding, the technical solution in the embodiments of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a disk, an optical disk, etc., and includes a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods of various embodiments of the present invention or certain parts of the embodiments.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0124] For ease of explanation, the above description has been made in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are intended to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. A projection device, characterized in that: include: a distance sensor configured to collect distance data; An optical machine configured to project images and playback content onto a projection surface; A camera is configured to photograph the projection surface to obtain a projection content image; The controller is configured as: responding to a power-on command; Acquire distance data at the time of power-on and distance data at the time of historical power-off, wherein the distance data is the distance between the optical machine and the projection surface; According to the distance data at the power-on time and the distance data at the historical power-off time, the distance change data of the power-on time relative to the historical power-off time is calculated; If the distance change data is greater than a preset distance threshold, the optical machine is controlled to project the calibration card image onto the projection surface, so as to calibrate the to-be-projected area of ​​the optical machine according to the calibration card image taken by the camera, and the to-be-projected area is used to present the image and play content; If the distance change data is less than or equal to the preset distance threshold, the step of controlling the optical machine to project the correction card image to the projection surface to correct the area to be projected of the optical machine according to the correction card image taken by the camera is not performed.

2. The projection device according to claim 1, characterized in that: The controller is also configured to: Parsing the power-on distance value from the distance data at the power-on time, and parsing the historical power-off distance value from the distance data at the historical power-off time; If the power-on distance value and the historical power-off distance value are within the effective distance range, the process of calculating the distance change data is executed; the effective distance range is set according to the setting positions of the distance sensor and the projection surface.

3. The projection device according to claim 2, characterized in that: The controller is also configured to: In the step of calculating the distance change data, the historical shutdown distance value is subtracted from the startup distance value, and the absolute value of the difference is extracted to generate a distance difference value; Calculating a ratio of the distance difference to the power-on distance value; If the ratio is greater than a preset ratio threshold, a process of projecting a correction card onto the projection surface is performed.

4. The projection device according to claim 2, characterized in that: The controller is also configured to: Get the distance data at the current moment; parsing a current distance value in the distance data; If the current distance value is within the effective distance range, assigning a data tag corresponding to the distance data at the current moment to a first state identifier, wherein the first state identifier is used to indicate that the current distance value is a valid distance; If the current distance value is not within the valid distance range, the data tag corresponding to the distance data at the current moment is assigned a second state identifier, and the second state identifier is used to indicate that the current distance value is an invalid distance.

5. The projection device according to claim 1, characterized in that: The system further includes an acceleration sensor configured to collect acceleration data; and the controller is configured to: Before the step of controlling the optical machine to project the correction card onto the projection surface, acquiring acceleration data at the startup time and acceleration data at the historical shutdown time; Calculating acceleration change data based on the acceleration data at the startup time and the acceleration data at the historical shutdown time; If the acceleration change data is less than a preset acceleration threshold, the step of projecting a correction card onto the projection surface is performed.

6. The projection device according to claim 5, characterized in that: The controller is also configured to: Analyzing the movement angle of the projection device in the three axis coordinate directions in the acceleration change data; If the moving angles in the three axis coordinate directions are all smaller than the preset acceleration threshold, it is determined that the acceleration change data is smaller than the preset acceleration threshold.

7. The projection device according to claim 1, characterized in that: The calibration card includes calibration feature points; the controller is further configured to: In the step of correcting the to-be-projected area of ​​the optical machine according to the correction card image taken by the camera, the image position of the correction feature point in the correction card image is determined, and a projection relationship is obtained according to the image position, wherein the projection relationship is a mapping relationship between the playback content projected by the optical machine and the projection surface; The area to be projected is corrected according to the projection relationship.

8. The projection device according to claim 7, characterized in that: The controller is also configured to: In the step of acquiring the projection relationship according to the image position, the camera coordinates of the calibration feature points in the camera coordinate system are acquired according to the image position; Converting the camera coordinates into optomechanical coordinates of the calibration feature points in an optomechanical coordinate system; A homography matrix of the projection surface in an optomechanical coordinate system is acquired according to the optomechanical coordinates, where the homography matrix is ​​used to characterize the projection relationship.

9. A trigger correction method, characterized in that: Applied to a projection device, the projection device includes a distance sensor, an optical machine, a camera and a controller; the method specifically includes the following steps: responding to a power-on command; Acquire the distance data at the time of power-on and the distance data at the time of historical power-off, wherein the distance data is the distance between the optical machine and the projection surface; According to the distance data at the power-on time and the distance data at the historical power-off time, the distance change data of the power-on time relative to the historical power-off time is calculated; If the distance change data is greater than a preset distance threshold, the optical machine is controlled to project the calibration card image onto the projection surface, so as to calibrate the to-be-projected area of ​​the optical machine according to the calibration card image taken by the camera, and the to-be-projected area is used to present images and play content; If the distance change data is less than or equal to the preset distance threshold, the step of controlling the optical machine to project the correction card image to the projection surface to correct the area to be projected of the optical machine according to the correction card image taken by the camera is not performed.

10. The method according to claim 9, characterized in that The method further comprises: Parsing the power-on distance value from the distance data at the power-on time, and parsing the historical power-off distance value from the distance data at the historical power-off time; If the power-on distance value and the historical power-off distance value are within the effective distance range, the process of calculating the distance change data is executed; the effective distance range is set according to the setting positions of the distance sensor and the projection surface.

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