Projection screen correction method, projection display system and related devices

Abstract

The present invention provides a projection screen correction method. A scanning line is projected onto a screen by a projection terminal, and the projection screen coordinate information of the scanning line on the projection screen is sent to the screen. The screen controls at least four optoelectronic sensors to perform brightness detection. When each optoelectronic sensor is irradiated by the scanning line, the screen analyzes and obtains the projection screen coordinate information of each optoelectronic sensor. The screen calculates the coordinate correspondence information of each optoelectronic sensor based on the screen coordinate information and the projection screen coordinate information of each optoelectronic sensor and sends it to the projection terminal. The projection terminal calculates the transformation matrix between the current projection screen and the screen according to the coordinate correspondence information, and uses the transformation matrix as the input parameter for projection screen correction to achieve the adaptation of the boundary of the projection screen to the boundary of the screen. Compared with the related art, the projection screen correction method of the present invention is simple to operate, has a simple operation process, and has a high efficiency of automatic correction of the projection screen.

Description

Technical Field

[0001] The present invention relates to the field of projection technology, and in particular, to a projection screen correction method, a projection display system and related devices thereof. Background Art

[0002] In real life, projection devices are more and more widely used. In order to ensure good projection and viewing effects, it is necessary to correct the projection screen of the projection device.

[0003] In the related art, a camera provided on the projection device or another mobile terminal is used to capture the current projection screen to be corrected, and the to-be-corrected image information corresponding to the current projection screen to be corrected is obtained. The to-be-corrected image information is compared and calculated with the preset screen plane information to obtain a transformation matrix between the to-be-corrected projection screen and the screen plane, and the to-be-corrected projection screen is adjusted according to the transformation matrix so that the projection screen fits the screen plane.

[0004] However, in the related art, the user needs to first capture the to-be-corrected projection screen and obtain the to-be-corrected image information, which is inconvenient to operate and has a poor user experience. At the same time, since the process of comparing and calculating the to-be-corrected image information with the preset screen plane information is complex and has a large amount of calculation, the automatic correction efficiency of the projection screen is limited, resulting in slow correction of the projection screen.

[0005] Therefore, it is necessary to provide a new projection screen correction method, a projection display system and related devices thereof to solve the above technical problems. Summary of the Invention

[0006] The object of the present invention is to provide a projection screen correction method, a projection display system and related devices thereof to solve the problem of slow correction speed caused by inconvenient operation and large amount of calculation.

[0007] To achieve the above object, the present invention provides a projection screen correction method, which is applied to a projection terminal and includes the following steps:

[0008] Step S11, the projection terminal projects a scanning line onto the screen and sends the projection screen coordinate information of the scanning line on the projection screen to the screen;

[0009] Step S12, the projection terminal receives at least four groups of coordinate correspondence information; wherein, the coordinate correspondence information is the correspondence information between the screen coordinate information of the optoelectronic sensor and the projection screen coordinate information of the optoelectronic sensor calculated by the screen when the optoelectronic sensor is irradiated by the scanning line;

[0010] Step S13, the projection terminal calculates a transformation matrix between the current projection screen and the screen according to the at least four groups of coordinate correspondence information obtained;

[0011] Step S14, the projection terminal uses the transformation matrix as the input parameter for the projection screen correction to adapt the boundary of the projection screen to the boundary of the screen.

[0012] Preferably, in step S11, the projection terminal projects scan lines onto the screen in a frame-by-frame output manner to control the scan lines to scan the entire calibration start screen, and sends the projection screen coordinate information of the scan lines of each frame to the screen. During the scanning process, the scan lines sequentially irradiate each of the photoelectric sensors.

[0013] Preferably, step S11 includes:

[0014] The projection terminal projects a first scan line onto the screen in a frame-by-frame output manner to control the first scan line to scan the entire calibration start screen along a first coordinate direction, and sends the first coordinate information corresponding to the first coordinate direction of the first scan line of each frame to the screen in real time. During the scanning process, the first scan line sequentially irradiates each of the photoelectric sensors; and,

[0015] The projection terminal projects a second scan line onto the screen in a frame-by-frame output manner to control the second scan line to scan the entire calibration start screen along a second coordinate direction, and sends the second coordinate information corresponding to the second coordinate direction of the second scan line of each frame to the screen in real time. During the scanning process, the second scan line sequentially irradiates each of the photoelectric sensors; wherein, the second coordinate direction is cross-set with the first coordinate direction;

[0016] In step S13, the projection terminal calculates the transformation matrix between the current projection screen and the screen according to at least four groups of the first coordinate corresponding information and at least four groups of the second coordinate corresponding information obtained.

[0017] The present invention provides a projection screen correction method, which is applied to a screen and includes the following steps:

[0018] Step S21, the screen receives the scan lines projected by the projection terminal and receives the projection screen coordinate information of the scan lines on the projection screen;

[0019] Step S22, the screen controls at least four photoelectric sensors to perform brightness detection. When the brightness detected by one of the photoelectric sensors increases significantly compared with the ambient light, the screen analyzes and obtains the projection screen coordinate information of the scan line currently irradiating on the photoelectric sensor as the projection screen coordinate information of the photoelectric sensor;

[0020] Step S23: The screen calculates the coordinate correspondence information of each of the photoelectric sensors based on the screen coordinate information and the projected image coordinate information of each of the photoelectric sensors respectively.

[0021] Step S24: The screen sends the coordinate correspondence information to the projection terminal.

[0022] Preferably, before step S21, it further includes:

[0023] The screen receives the projected image projected by the projection terminal, and the screen determines whether all of the photoelectric sensors detect a significant increase in brightness compared to the ambient light at the same time under the illumination of the projected image. If so, the current projected image is calibrated as the calibration start image, and the calibration time is recorded as the calibration start time.

[0024] In step S21, the screen receives each frame of the scan lines in a frame-by-frame manner and receives the projected image coordinate information of each frame of the scan lines in real time.

[0025] Step S22 includes:

[0026] Step S221: The screen controls at least four of the photoelectric sensors to perform brightness detection. When one of the photoelectric sensors receives the scan line, the photoelectric sensor detects a significant increase in brightness compared to the ambient light, and the screen receives the high-level signal generated by the photoelectric sensor.

[0027] Step S222: The screen analyzes and obtains the projected image coordinate information of the scan line currently illuminating the photoelectric sensor based on the time difference between the time when the photoelectric sensor generates an electrical signal and the calibration start time, and combines it with the projected image coordinate information of each frame of the scan lines, and uses it as the projected image coordinate information of the photoelectric sensor.

[0028] Preferably, step S221 includes:

[0029] When the photoelectric sensor receives the first scan line, the screen receives the first high level generated by the photoelectric sensor; and,

[0030] When the photoelectric sensor receives the second scan line, the screen receives the second high level generated by the photoelectric sensor.

[0031] Step S222 includes:

[0032] The screen calculates, based on the time difference between the reception time of the first high level and the calibration start time, the first coordinate information of the first scan line irradiated on the photoelectric sensor in the first coordinate direction as the first projection screen coordinate information of the photoelectric sensor; and,

[0033] The screen calculates, based on the time difference between the reception time of the second high level and the calibration start time, the second coordinate information of the second scan line irradiated on the photoelectric sensor in the second coordinate direction as the second projection screen coordinate information of the photoelectric sensor.

[0034] Preferably, the step S23 includes:

[0035] The screen calculates the first coordinate corresponding information of each photoelectric sensor based on the first projection screen coordinate information of each photoelectric sensor and the first screen coordinate information of each photoelectric sensor; and,

[0036] The screen calculates the second coordinate corresponding information of each photoelectric sensor based on the second projection screen coordinate information of each photoelectric sensor and the second screen coordinate information of each photoelectric sensor;

[0037] In the step S24, the screen sends the first coordinate corresponding information and the second coordinate corresponding information to the projection terminal.

[0038] The present invention provides a projection display system, which includes a projection terminal, a screen communicatively connected to the projection terminal, and at least four photoelectric sensors disposed on the screen;

[0039] The projection terminal is configured to project scan lines onto the screen, and send the projection screen coordinate information of the scan lines on the projection screen to the screen; to receive at least four groups of coordinate corresponding information; to calculate a transformation matrix between the current projection screen and the screen based on the obtained at least four groups of coordinate corresponding information; to use the transformation matrix as an input parameter for projection screen calibration to achieve adaptation of the boundary of the projection screen to the boundary of the screen; and / or,

[0040] The screen is configured to receive the scan lines projected by the projection terminal and receive the projection screen coordinate information of the scan lines on the projection screen; it is used to control at least four of the photoelectric sensors to perform brightness detection. When the brightness detected by one of the photoelectric sensors increases significantly compared to the ambient light, the projection screen coordinate information of the scan line currently irradiating on this photoelectric sensor is parsed and obtained as the projection screen coordinate information of this photoelectric sensor; it is used to calculate the coordinate correspondence information of each of the photoelectric sensors respectively according to the screen coordinate information of each of the photoelectric sensors and the projection screen coordinate information of each of the photoelectric sensors; it is used to send the coordinate correspondence information to the projection terminal.

[0041] The present invention provides a projection display system, which includes a processor and a memory. A control program for the processor to execute is stored in the memory. Wherein, when the control program is executed by the processor, it implements the steps of the projection screen correction method applied to the projection terminal of the present invention, and / or implements the steps of the projection screen correction method applied to the screen of the present invention.

[0042] The present invention provides a computer-readable storage medium, which stores a computer program; when the computer program is executed by a processor, it implements the steps of the projection screen correction method applied to the projection terminal of the present invention, and / or implements the steps of the projection screen correction method applied to the screen of the present invention.

[0043] Compared with the related art, in the projection screen correction method of the present invention, scan lines are projected from the projection terminal onto the screen, and the projection screen coordinate information of the scan lines on the projection screen is sent to the screen. The screen controls at least four photoelectric sensors to perform brightness detection. When the brightness detected by one of the photoelectric sensors increases significantly compared to the ambient light, the projection screen coordinate information of this photoelectric sensor is parsed and obtained by the screen. The screen calculates the coordinate correspondence information of each photoelectric sensor according to the screen coordinate information and the projection screen coordinate information of each photoelectric sensor and sends it to the projection terminal. The projection terminal calculates the transformation matrix between the current projection screen and the screen according to the coordinate correspondence information and uses the transformation matrix as the input parameter for projection screen correction to achieve the adaptation of the boundary of the projection screen to the boundary of the screen; in the above method, by directly irradiating the scan lines on each photoelectric sensor in sequence, the projection screen coordinate information of each photoelectric sensor can be obtained, and then the coordinate correspondence information is obtained according to the preset conversion relationship between the screen coordinate information and the projection screen coordinate information. The transformation matrix is calculated according to the coordinate correspondence information. There is no need to separately obtain the image information of the current projection screen, which simplifies the operation process. It only needs to scan in sequence, and there is no need to perform data processing operations in the projector, which simplifies the operation process, improves the efficiency of automatic correction of the projection screen, and effectively improves the user experience. Description of the Drawings

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings, where:

[0045] Figure 1 It is a schematic flowchart of a projection screen correction method applied to a projection terminal according to the present invention;

[0046] Figure 2 It is a schematic flowchart of a projection screen correction method applied to a screen according to the present invention;

[0047] Figure 3 is Figure 2 a specific schematic flowchart of step S22 in;

[0048] Figure 4 It is a schematic structural diagram of a projection display system according to the present invention;

[0049] Figure 5 It is a schematic diagram of a projection terminal of the present invention projecting a projection screen onto a screen;

[0050] Figure 6 It is a schematic diagram of a projection terminal of the present invention scanning a calibration startup screen. Specific embodiments

[0051] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0052] Please refer to Figure 1 As shown, the present invention also provides a projection screen correction method applied to a projection terminal. This method is applied to the projection terminal of a projection display system, and this method at least includes the following steps:

[0053] Step S11, the projection terminal projects scan lines onto the screen and sends the projection screen coordinate information of the scan lines on the projection screen to the screen in real time;

[0054] Step S12, the projection terminal receives at least four groups of coordinate correspondence information; wherein, the coordinate correspondence information is the correspondence information between the screen coordinate information of the optoelectronic sensor calculated by the screen and the projection screen coordinate information of the optoelectronic sensor when the optoelectronic sensor is irradiated by the scanning line;

[0055] Step S13, the projection terminal calculates a transformation matrix between the boundary of the current projection screen and the boundary of the screen according to the at least four groups of coordinate correspondence information obtained;

[0056] Step S14, the projection terminal uses the transformation matrix as the input parameter for projection screen correction to achieve the adaptation of the boundary of the projection screen to the boundary of the screen, that is, to project the projection screen on the screen in a suitable form.

[0057] Please refer to Figure 2 This invention also provides a projection screen correction method for a screen applied to a projection display system. As shown in the figure, the method at least includes the following steps:

[0058] Step S21, the screen receives the scanning line projected by the projection terminal and receives the projection screen coordinate information of the scanning line on the projection screen;

[0059] Step S22, the screen controls at least four optoelectronic sensors to perform brightness detection. When the brightness detected by one of the optoelectronic sensors increases significantly compared to the ambient light, the screen analyzes and obtains the projection screen coordinate information of the scanning line currently irradiating the optoelectronic sensor as the projection screen coordinate information of the optoelectronic sensor;

[0060] Step S23, the screen calculates the coordinate correspondence information of each optoelectronic sensor according to the screen coordinate information and the projection screen coordinate information of each optoelectronic sensor respectively;

[0061] Step S24, the screen sends the coordinate correspondence information to the projection terminal.

[0062] As Figure 3 shown, more specifically, in step S22, it includes:

[0063] Step S221, the screen controls at least four of the optoelectronic sensors to perform brightness detection. When one of the optoelectronic sensors receives the scanning line and the brightness detected by the optoelectronic sensor increases significantly compared to the ambient light, the screen receives the high-level signal generated by the optoelectronic sensor;

[0064] Step S222: The screen analyzes and obtains the projected picture coordinate information of the scan line currently irradiating the photoelectric sensor as the projected picture coordinate information of the photoelectric sensor based on the time difference between the time when the photoelectric sensor generates an electrical signal and the calibration start time, and combines the projected picture coordinate information of each frame of the scan line.

[0065] Please refer to Figure 4 As shown, the present invention also provides a projection display system 100, which includes a projection terminal 1, a screen 2 communicatively connected to the projection terminal 1, and at least four photoelectric sensors 3 disposed on the screen.

[0066] In this embodiment, the projection terminal 1 includes a projector 11, a controller 12, and a communication module 13.

[0067] Among them, the projector 11 is a conventional projector, and the projector 11 can project a specific sequence of picture frames onto the screen 2 under the control of software; a geometric correction unit is provided inside the projector 11, and the geometric correction unit can be implemented by a dedicated ASIC or FPGA on the projector 11. It takes the conversion matrix between the screen and the picture to be corrected projected by the projector 11 as an input, and controls the projection picture to perform "inverse deformation", and combines the control of the zoom of the lens to adjust the boundary of the projection picture to match the boundary of the screen 2, that is, after adjustment, the projection picture irradiates evenly on the screen; the controller 12 can be the MCU / CPU of the projector 11 or other control units, and specific selection can be made according to the actual application requirements.

[0068] The screen 2 includes a screen body 21 for the projection, a controller 22, and a communication module 23.

[0069] Among them, the screen body 21 serves as a projection reference plane, and the projection picture and scan line projected by the projection terminal 1 are projected on the screen body 21.

[0070] The controller 22 is used to control the photoelectric sensor 3 to sense the illuminance and detect the electrical signal output by the photoelectric sensor 3.

[0071] The communication module 23 can be directly integrated inside the controller 22 or externally connected to the embedded components of the controller 22; the communication module 23 of the screen 2 can be communicatively connected to the communication module 13 in the projection terminal 1. The communication channel between the two is any one of a wireless channel, an infrared channel, and a wired channel; the wireless channel is preferably any one of electromagnetic waves, Wifi, and Bluetooth.

[0072] The photoelectric sensor 3 is used to detect changes in brightness. Through special design, its detection window can be made smaller to ensure the accuracy of line detection. The photoelectric sensor 3 is controlled by the controller 22 on the screen 2 to sense the illuminance at a specific position on the screen 2. When light shines on the photoelectric sensor 3, the photoelectric sensor 3 detects that the brightness has increased significantly compared to the ambient light, converts the optical signal into an electrical signal, and transmits it to the screen 2.

[0073] It is worth mentioning that the number of the photoelectric sensors 3 is not limited and can be set according to actual usage needs. To improve the accuracy of automatic adjustment, more photoelectric sensors can be set. For example, in this embodiment, the photoelectric sensor 3 includes four, and the four photoelectric sensors 3 are installed on the screen main body 21. The installation positions of the photoelectric sensors 3 on the screen 2 determine the coordinates of the photoelectric sensor 3, that is, the screen coordinate information of each photoelectric sensor 3 on the screen main body 21 is preset.

[0074] When the above projection display system 100 applies the projection screen correction method of the present invention:

[0075] The projection terminal 1 is used to project scan lines onto the screen 2, send the projection screen coordinate information of the scan lines on the projection screen to the screen 2, receive at least four groups of coordinate corresponding information, calculate the transformation matrix between the current projection screen and the screen based on the obtained at least four groups of coordinate corresponding information, and use the transformation matrix as the input parameter for projection screen correction to make the boundary of the projection screen fit the boundary of the screen, that is, to project the projection screen onto the screen in a suitable form.

[0076] The screen 2 is used to receive the scan lines projected by the projection terminal 1 and receive the projection screen coordinate information of the scan lines on the projection screen; it is used to control at least four photoelectric sensors 3 to perform brightness detection. When one of the photoelectric sensors 3 detects that the brightness has increased significantly compared to the ambient light, the projection screen coordinate information of the scan line currently irradiating on the photoelectric sensor 3 is parsed and obtained as the projection screen coordinate information of the photoelectric sensor 3; it is used to calculate the coordinate corresponding information of each photoelectric sensor 3 respectively according to the screen coordinate information and the projection screen coordinate information of each photoelectric sensor 3; and it is used to send the coordinate corresponding information to the projection terminal 1.

[0077] To facilitate understanding of the above method, the following will be combined with Figures 4-6 the specific structure of the projection display system shown, to describe the above method in detail:

[0078] The first step, asFigure 5 As shown, the projector 11 of the projection terminal 1 projects a projection image onto the screen body 21 of the screen 2. The screen 2 receives the projection image projected by the projection terminal 1. The controller 22 of the screen 2 determines whether the four optoelectronic sensors 3 detect a significant increase in brightness compared to the ambient light at the same time under the illumination of the projection image. If so, the current projection image is calibrated as the calibration start image H0, and the calibration time is recorded as the calibration start time T0.

[0079] It should be noted that the projection image needs to cover all the optoelectronic sensors 3 on the screen 2 before it can be calibrated as the calibration start image H0. Therefore, in this embodiment, the projection image needs to cover the four optoelectronic sensors 3.

[0080] In the second step, the projector 11 projects scan lines onto the screen body 21 and sends the projection image coordinate information of the scan lines on the projection image to the screen. Specifically, the projector 11 projects scan lines onto the screen body 21 in a frame-by-frame output manner to control the scan lines to scan the entire calibration start image H0. The communication module 13 of the projection terminal 1 sends the projection image coordinate information of each frame of the scan lines to the screen 2, and the scan lines sequentially irradiate each of the optoelectronic sensors 3 during the scanning process.

[0081] The screen body 21 receives the scan lines projected by the projector 11, and the communication module 23 of the screen 2 receives the projection image coordinate information of the scan lines on the projection image. The screen body 21 receives each frame of the scan lines in a frame-by-frame reception manner, and the communication module 23 receives the projection image coordinate information of each frame of the scan lines.

[0082] The screen 2 receives the coordinate information of each frame of the scan lines corresponding to the calibration start image H0 through the communication module 23, and receives the high level generated by each of the optoelectronic sensors 3 through the controller 22.

[0083] In the second step, more specifically, as Figure 6 shown in (a),

[0084] The projector 11 projects the first scan line P onto the screen body 21 in a frame-by-frame output manner x to control the first scan line P x to scan the entire calibration start image H0 along the first coordinate direction (i.e., the X-axis direction). The communication module 13 sends the first coordinate information corresponding to the first coordinate direction of each frame of the first scan line P x to the communication module 23. During the scanning process, the first scan line P xThey are sequentially irradiated on each of the photoelectric sensors 3.

[0085] As Figure 6 As shown in (b), the projector 11 projects the second scanning line P onto the screen 2 in a frame-by-frame output manner y to control the second scanning line P y to scan the entire calibration start screen H0 along the second coordinate direction (i.e., the Y-axis direction). The communication module 11 sends the second coordinate information corresponding to the second coordinate direction of each frame of the second scanning line P y to the communication module 23. During the scanning process, the second scanning line P y is sequentially irradiated on each of the photoelectric sensors; wherein, the second coordinate direction (Y-axis direction) is arranged to intersect with the first coordinate direction (X-axis direction).

[0086] In the third step, the controller 22 of the screen 2 controls the four photoelectric sensors 3 to perform brightness detection. When the brightness detected by one of the photoelectric sensors 3 is significantly increased compared to the ambient light, the controller 22 analyzes and obtains the projection screen coordinate information of the scanning line currently irradiated on this photoelectric sensor 3 as the projection screen coordinate information of this photoelectric sensor 3.

[0087] Specifically, the controller 22 controls the four photoelectric sensors 3 to perform brightness detection. When one of the photoelectric sensors 3 receives the scanning line, the brightness detected by this photoelectric sensor 3 is significantly increased compared to the ambient light and a high-level signal is generated. The controller 22 receives the high-level signal generated by this photoelectric sensor 3.

[0088] The controller 22 analyzes and obtains the projection screen coordinate information of the scanning line currently irradiated on this photoelectric sensor 3 as the projection screen coordinate information of this photoelectric sensor 3 according to the time difference between the time when this photoelectric sensor 3 generates an electrical signal and the calibration start time T0, and in combination with the projection screen coordinate information of each frame of the scanning line.

[0089] Further, in this embodiment, when one of the photoelectric sensors 3 receives the first scanning line P x , the controller 22 receives the first high level generated by this photoelectric sensor 3. The controller 22 calculates and obtains the first coordinate information of the first scanning line P x currently irradiated on this photoelectric sensor 3 in the first coordinate direction (X-axis direction) as the first projection screen coordinate information of this photoelectric sensor 3; when one of the photoelectric sensors 3 receives the second scanning line P yWhen the controller 22 receives the second high level generated by the photoelectric sensor 3, the controller 22 calculates and obtains the second scan line P currently irradiating the photoelectric sensor 3 based on the time difference between the reception time of the second high level and the calibration start time T0. y The second coordinate information in the second coordinate direction (Y-axis direction) is used as the second projection screen coordinate information of the photoelectric sensor 3.

[0090] Step 4: The controller 22 of the screen 2 calculates the coordinate correspondence information of each photoelectric sensor 3 based on the screen coordinate information and the projection screen coordinate information of each photoelectric sensor 3 respectively; the communication module 23 of the screen 2 sends the coordinate correspondence information to the projection terminal 1, and the communication module 13 of the projection terminal 1 receives four groups of the coordinate correspondence information.

[0091] Specifically, the controller 22 calculates the first coordinate correspondence information of each photoelectric sensor 3 based on the correspondence between the first projection screen coordinate information and the first screen coordinate information of each photoelectric sensor 3; the controller 22 calculates the second coordinate correspondence information of each photoelectric sensor 3 based on the correspondence between the second projection screen coordinate information and the second screen coordinate information of each photoelectric sensor 3.

[0092] The communication module 23 sends four groups of the first coordinate correspondence information and four groups of the second coordinate correspondence information of the four photoelectric sensors 3 to the projection terminal 1; the communication module 13 of the projection terminal 1 receives the above four groups of the first coordinate correspondence information and four groups of the second coordinate correspondence information.

[0093] Step 5: The controller 12 of the projection terminal 1 calculates the transformation matrix between the current projection screen and the screen based on the four groups of the obtained coordinate correspondence information.

[0094] Specifically, the controller 12 calculates the transformation matrix between the current projection screen and the screen based on the four groups of the obtained first coordinate correspondence information and four groups of the second coordinate correspondence information.

[0095] Step 6: The projection terminal 1 uses the transformation matrix as the input parameter for the projection screen calibration. Specifically, the geometric calibration unit of the projector 11 controls the projection screen to perform "inverse deformation" according to the transformation matrix, and combines the control of the lens zoom to make the boundary of the projection screen match the boundary of the screen 2, that is, after adjustment, the projection screen irradiates evenly on the screen body 21.

[0096] The present invention provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the steps of the projection screen correction method applied to a projection terminal according to the present invention are implemented.

[0097] The present invention provides a projection display system, which includes a projection terminal, a screen communicatively connected to the projection terminal, and at least four optoelectronic sensors disposed on the screen.

[0098] The present invention provides a projection display system, which includes a processor and a memory, and a control program for execution by the processor is stored in the memory. Wherein, when the control program is executed by the processor, the steps of the projection screen correction method applied to a projection terminal according to the present invention are implemented, and / or the steps of the projection screen correction method applied to a screen according to the present invention are implemented.

[0099] The present invention provides a computer-readable storage medium storing a computer program; when the computer program is executed by a processor, the steps of the projection screen correction method applied to a projection terminal according to the present invention are implemented, and / or the steps of the projection screen correction method applied to a screen according to the present invention are implemented.

[0100] Compared with the related art, in the projection screen correction method of the present invention, a scanning line is projected from a projection terminal onto a screen, and the projection screen coordinate information of the scanning line on the projection screen is sent to the screen. The screen controls at least four optoelectronic sensors to perform brightness detection. When the brightness detected by one of the optoelectronic sensors increases significantly compared with the ambient light, the screen analyzes and obtains the projection screen coordinate information of the optoelectronic sensor. The screen calculates the coordinate correspondence information of each optoelectronic sensor based on the screen coordinate information and the projection screen coordinate information of each optoelectronic sensor and sends it to the projection terminal. The projection terminal calculates the transformation matrix between the current projection screen and the screen according to the coordinate correspondence information, and uses the transformation matrix as the input parameter for projection screen correction to achieve the adaptation of the boundary of the projection screen to the boundary of the screen; in the above method, by directly irradiating the scanning line on each optoelectronic sensor in sequence, the projection screen coordinate information of each optoelectronic sensor can be obtained. This method no longer requires the projector to send coordinate information to the screen through communication, making the way for the screen to obtain coordinate information simpler and faster. Then, according to the preset conversion relationship between the screen coordinate information and the projection screen coordinate information, the coordinate correspondence information is obtained, and the conversion matrix is calculated based on the coordinate correspondence information. There is no need to obtain the image information of the current projection screen additionally, which simplifies the operation process and only requires sequential scanning. Moreover, there is no need to perform data processing operations in the projector, which simplifies the operation process and improves the efficiency of automatic projection screen correction, effectively improving the user experience.

[0101] The above are only the embodiments of the present invention. It should be noted here that for those of ordinary skill in the art, improvements can be made without departing from the inventive concept of the present invention, but these all fall within the protection scope of the present invention.

Claims

1. A projection screen correction method, which is applied to a projection terminal, and is characterized in that, The projection screen correction method includes the following steps: Step S11, the projection terminal projects a scanning line onto the screen and sends the projection screen coordinate information of the scanning line on the projection screen to the screen; Step S12, the projection terminal receives at least four groups of coordinate correspondence information; wherein, the coordinate correspondence information is the correspondence information between the screen coordinate information of the photosensor calculated by the screen and the projection screen coordinate information of the photosensor when the photosensor is irradiated by the scanning line. The screen coordinate information of the photosensor represents the coordinate of the photosensor in the screen, and the projection screen coordinate information of the photosensor represents the projection coordinate of the scanning line irradiated on the photosensor; Step S13, the projection terminal calculates the transformation matrix between the current projection screen and the screen according to the at least four groups of the obtained coordinate correspondence information; Step S14, the projection terminal uses the transformation matrix as the input parameter for the projection screen correction to realize the adaptation of the boundary of the projection screen to the boundary of the screen.

2. The projection screen correction method according to claim 1, wherein, In step S11, the projection terminal projects the scanning line onto the screen in a frame-by-frame output manner to control the scanning line to scan the entire correction start screen, and sends the projection screen coordinate information of each frame of the scanning line to the screen. During the scanning process, the scanning line irradiates each of the photosensors in sequence.

3. The projection screen correction method according to claim 2, wherein Step S11 includes: The projection terminal projects a first scanning line onto the screen in a frame-by-frame output manner to control the first scanning line to scan the entire correction start screen along a first coordinate direction, and sends the first coordinate information corresponding to the first coordinate direction of each frame of the first scanning line to the screen in real time. During the scanning process, the first scanning line irradiates each of the photosensors in sequence; and, The projection terminal projects a second scanning line onto the screen in a frame-by-frame output manner to control the second scanning line to scan the entire correction start screen along a second coordinate direction, and sends the second coordinate information corresponding to the second coordinate direction of each frame of the second scanning line to the screen in real time. During the scanning process, the second scanning line irradiates each of the photosensors in sequence; wherein, the second coordinate direction is arranged crosswise with the first coordinate direction; In step S13, the at least four groups of coordinate correspondence information include at least four groups of first coordinate correspondence information and at least four groups of second coordinate correspondence information. The projection terminal calculates the transformation matrix between the current projection screen and the screen according to the at least four groups of the obtained first coordinate correspondence information and at least four groups of the second coordinate correspondence information.

4. A projection screen correction method, which is applied to a screen, characterized in that, The projection screen correction method includes the following steps: Step S21, the screen receives the scanning line projected by the projection terminal and receives the projection screen coordinate information of the scanning line on the projection screen; Step S22: The screen controls at least four photoelectric sensors to perform brightness detection. When the brightness detected by one of the photoelectric sensors increases significantly compared to the ambient light, the screen analyzes and obtains the projection screen coordinate information of the scan line currently irradiating on this photoelectric sensor as the projection screen coordinate information of this photoelectric sensor. The screen coordinate information of the photoelectric sensor represents the coordinate of the photoelectric sensor in the screen, and the projection screen coordinate information of the photoelectric sensor represents the projection coordinates of the scan line irradiating on this photoelectric sensor; Step S23: The screen calculates the coordinate correspondence information of each photoelectric sensor respectively according to the screen coordinate information of each photoelectric sensor and the projection screen coordinate information of each photoelectric sensor; Step S24: The screen sends the coordinate correspondence information to the projection terminal.

5. The projection screen correction method according to claim 4, wherein, Before the step S21, it further includes: The screen receives the projection screen projected by the projection terminal, and the screen determines whether all the photoelectric sensors detect that the brightness increases significantly compared to the ambient light under the irradiation of the projection screen at the same time. If so, the current projection screen is calibrated as the calibration start screen, and the calibration time is recorded as the calibration start time; In the step S21, the screen receives each frame of the scan line in a frame-by-frame reception manner and receives the projection screen coordinate information of each frame of the scan line in real time; The step S22 includes: Step S221: The screen controls at least four of the photoelectric sensors to perform brightness detection. When one of the photoelectric sensors receives the scan line, the brightness detected by this photoelectric sensor increases significantly compared to the ambient light, and the screen receives the high-level signal generated by this photoelectric sensor; Step S222: The screen analyzes and obtains the projection screen coordinate information of the scan line currently irradiating on this photoelectric sensor as the projection screen coordinate information of this photoelectric sensor according to the time difference between the time when this photoelectric sensor generates an electrical signal and the calibration start time, and in combination with the projection screen coordinate information of each frame of the scan line.

6. The projection screen correction method according to claim 5, wherein The step S221 includes: When the photoelectric sensor receives the first scan line, the screen receives the first high level generated by this photoelectric sensor; and, When the photoelectric sensor receives the second scan line, the screen receives the second high level generated by this photoelectric sensor; The step S222 includes: The screen calculates and obtains the first coordinate information of the first scan line irradiating on this photoelectric sensor in the first coordinate direction as the first projection screen coordinate information of this photoelectric sensor according to the time difference between the reception time of the first high level and the calibration start time; and, The screen calculates and obtains the second coordinate information of the second scan line irradiating on this photoelectric sensor in the second coordinate direction as the second projection screen coordinate information of this photoelectric sensor according to the time difference between the reception time of the second high level and the calibration start time.

7. The projection screen correction method according to claim 6, wherein The step S23 includes: The screen calculates the first coordinate correspondence information of each of the photoelectric sensors based on the first projection screen coordinate information and the first screen coordinate information of each of the photoelectric sensors; and, The screen calculates the second coordinate correspondence information of each of the photoelectric sensors based on the second projection screen coordinate information and the second screen coordinate information of each of the photoelectric sensors; In the step S24, the screen sends the first coordinate correspondence information and the second coordinate correspondence information to the projection terminal.

8. A projection display system, which includes a projection terminal, a screen communicatively connected to the projection terminal, and at least four photoelectric sensors disposed on the screen, and is characterized in that, The projection terminal is configured to project scan lines onto the screen and send the projection screen coordinate information of the scan lines on the projection screen to the screen; and is configured to receive at least four sets of coordinate correspondence information; It is configured to calculate the transformation matrix between the current projection screen and the screen based on the at least four sets of the obtained coordinate correspondence information; and is configured to use the transformation matrix as the input parameter for correcting the projection screen to adapt the boundary of the projection screen to the boundary of the screen; and / or, The screen is configured to receive the scan lines projected by the projection terminal and receive the projection screen coordinate information of the scan lines on the projection screen; and is configured to control at least four of the photoelectric sensors to perform brightness detection. When the brightness detected by one of the photoelectric sensors increases significantly compared to the ambient light, the projection screen coordinate information of the scan line currently irradiating on this photoelectric sensor is parsed and obtained as the projection screen coordinate information of this photoelectric sensor; It is configured to calculate the coordinate correspondence information of each of the photoelectric sensors respectively based on the screen coordinate information and the projection screen coordinate information of each of the photoelectric sensors; It is configured to send the coordinate correspondence information to the projection terminal. The screen coordinate information of the photoelectric sensor represents the coordinate of the photoelectric sensor in the screen, and the projection screen coordinate information of the photoelectric sensor represents the projection coordinate of the scan line irradiating on this photoelectric sensor.

9. A projection display system, characterized in that, The projection display system includes a processor and a memory. A control program for the processor to execute is stored in the memory. Wherein, when the control program is executed by the processor, it implements the steps of the projection screen correction method applied to the projection terminal as described in any one of claims 1 to 3 above, and / or, implements the steps of the projection screen correction method applied to the screen as described in any one of claims 4 to 7 above.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the projection screen correction method applied to the projection terminal as described in any one of claims 1 to 3 above, and / or, implements the steps of the projection screen correction method applied to the screen as described in any one of claims 4 to 7 above.

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