Projection device and projection method thereof

Abstract

The invention provides a projection apparatus and a projection method. The projection device comprises a ray machine, a distance measuring unit and a processor. The ray machine is used for projecting an image beam to the target area to form a first image. The distance measuring unit is used for emitting test light to the target area, detecting reflected light formed by reflecting the test light and taking out effective detection information. The processor is coupled to the distance measuring unit and the ray machine. A portion of the test light penetrates the target region. The processor is used for receiving the effective detection information from the distance measuring unit and generating first projection distance information according to the effective detection information. The processor is used for controlling the ray machine to project an image beam to the target area according to the first projection distance information, so that a first image corresponding to the image beam is located in an effective focal length range of the projection device. According to the projection device and the projection method provided by the invention, the interference of the obstacle on the focusing of the projection device can be improved, and image correction can be carried out by using a correct sensing result.

Description

Technical Field

[0001] The present invention relates to a device and a method, and more particularly to a projection device and a projection method thereof. Background Art

[0002] When the projection device is projecting, it can often automatically focus according to the sensing result of the distance measuring unit. However, in different usage situations, for example, the sensing result of the distance measuring unit may be disturbed by obstacles in front of the projection screen, or the material properties of the projection screen itself may interfere, causing the test light of the distance measuring unit to penetrate the projection screen to the wall behind it, resulting in abnormal sensing results. The projection device may fail to perform keystone correction or focus on the wrong plane due to the use of abnormal sensing results, which seriously affects the user's experience of using the projection device.

[0003] The "background technology" section is only used to help understand the content of the present invention. Therefore, the content disclosed in the "background technology" section may contain some known technologies that are not known to those skilled in the art. The content disclosed in the "background technology" section does not mean that the content or the problems to be solved by one or more embodiments of the present invention have been known or recognized by those skilled in the art before the application of the present invention. Summary of the invention

[0004] The invention provides a projection device and a projection method thereof, which can improve the interference of obstacles on the focus of the projection device and can use the correct sensing result to perform image correction.

[0005] To achieve one or part or all of the above purposes or other purposes, a projection device according to one embodiment of the present invention is used for projecting onto a target area. The projection device includes an optical machine, a distance measuring unit and a processor. The optical machine is used to project an image beam to form a first image. The distance measuring unit is used to emit a test light to the target area, and to detect the reflected light formed by the reflection of the test light and extract the effective detection information. The processor couples the distance measuring unit and the optical machine. A portion of the test light penetrates the target area, and the processor is used to receive the effective detection information from the distance measuring unit, and to generate the first projection distance information based on the effective detection information, and the processor is used to control the optical machine to project the image beam to the target area based on the first projection distance information, so that the first image corresponding to the image beam is within the effective focal length range of the projection device.

[0006] To achieve one or part or all of the above purposes or other purposes, a projection method according to an embodiment of the present invention is used to control the operation of a projection device, the projection device comprising an optical machine, a distance measuring unit and a processor. The projection method comprises: emitting a test light to a target area by the distance measuring unit, detecting reflected light formed by the reflection of the test light and extracting effective detection information, wherein a part of the test light penetrates the target area; receiving effective detection information from the distance measuring unit by the processor, and generating first projection distance information according to the effective detection information; and controlling an image beam projected by the optical machine to the target area by the processor according to the first projection distance information, so that a first image formed by the corresponding image beam is located within the effective focal length range of the projection device.

[0007] Based on the above, the projection device and projection method of the present invention can properly eliminate the reflection generated by obstacles to avoid interference when judging the distance and direction of the projection screen. In addition, the projection device of the present invention can eliminate the material factor of the projection screen itself, and the projection device can use the correct sensing result to perform image correction.

[0008] Other purposes and advantages of the present invention can be further understood from the technical features disclosed in the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 FIG. 1 is a block diagram of a projection device according to an embodiment of the present invention.

[0010] Figure 2 FIG. 4 is a schematic diagram of detection information generated by a distance measurement unit according to an embodiment of the present invention.

[0011] Figure 3A The present invention is a stereoscopic diagram of a projection device emitting test light to a projection screen.

[0012] Figure 3B The present invention is a stereoscopic diagram of a projection device emitting test light to a projection screen.

[0013] Figures 4A to 4K Schematic diagrams of different situations when the projection device performs distance measurement according to an embodiment of the present invention.

[0014] Figure 5A The figure is a flow chart of a projection method according to an embodiment of the present invention.

[0015] Figure 5B The figure is a flow chart of a projection method according to an embodiment of the present invention.

[0016] Description of reference numerals:

[0017] 1: Projection device

[0018] 10: Distance measuring unit

[0019] 11: Processor

[0020] 12: Optical machine

[0021] A1~A3、B1~B3、A11~A15、A21~A29、B11~B15、B21~B29、P、R:Point

[0022] D1~D4: Distance

[0023] G1~G4:Group

[0024] SCR: Projection Screen

[0025] S511~S513, S521~S526: Steps

[0026] OBJ: Obstacle

[0027] OBJ1~OBJ3: obstacles. DETAILED DESCRIPTION

[0028] The above-mentioned other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of a preferred embodiment with reference to the accompanying drawings. The directional terms mentioned in the following embodiments, such as up, down, left, right, front or back, etc., are only the directions with reference to the accompanying drawings. Therefore, the directional terms used are used to illustrate and not to limit the present invention.

[0029] Figure 1 1 is a block diagram of a projection device 1 according to an embodiment of the present invention. The projection device 1 includes a distance measuring unit 10, a processor 11 and an optical engine 12. In some embodiments, the projection device 1 is used to project onto a target area, and the target area is, for example, a projection screen or a projection film attached to a glass plate, which is suitable for presenting an image. The following embodiments will be described using the projection screen as the target area. The optical engine 12 of the projection device 1 can be used to project an image beam toward the projection screen to form a first image corresponding to the image beam on the projection screen. In order to enable the optical engine 12 to be presented on the projection screen with better imaging quality, the projection device 1 uses the distance measuring unit 10 to detect the distance between the projection device 1 and the projection screen, and the processor 11 is coupled to the distance measuring unit 10. More specifically, the distance measuring unit 10 can be used to emit a test light to the projection screen and detect the reflected light formed by the reflection of the test light. The distance measuring unit 10 detects the reflected light and extracts the effective detection information. Further, the processor 11 can be used to receive the effective detection information provided by the distance measuring unit 10 and generate the first projection distance information according to the effective detection information. Accordingly, the processor 11 can control the image beam projected by the optical machine 12 to the position of the projection screen according to the first projection distance information, so that the first image corresponding to the image beam is located within the effective focal length range of the projection device 1 (indicating that based on the correct distance information, the first image can present a clear image on the projection screen).

[0030] In some embodiments, the distance measuring unit 10 may be, for example, a 3D camera or a time of flight (ToF) sensor, which can shoot a target range and obtain depth information of each object in the shot image. In some embodiments, the processor 11 may be, for example, a central processing unit (CPU), or other programmable general-purpose or special-purpose micro control unit (MCU), microprocessor, digital signal processor (DSP), programmable controller, application specific integrated circuit (ASIC), graphics processing unit (GPU), arithmetic logic unit (ALU), complex programmable logic device (CPLD), field programmable gate array (FPGA), any other type of integrated circuit, state machine, processor based on advanced reduced instruction set machine (ARM), or other similar components or combinations of the above components. In some embodiments, the optical engine 12 may include, for example, a light source, at least one light valve (such as a digital micromirror device (DMD) or a liquid crystal on silicon (LCoS) panel), and other lens structures including, for example, one or more optical lenses with refractive power.

[0031] Specifically, the distance measuring unit 10 can emit a test light and sense the reflected light reflected by the test light from the reflective object, wherein the test light emitted by the distance measuring unit 10 toward the target area can cover multiple different detection points on the target area. The distance measuring unit 10 can generate the distance or depth information from the test unit 10 to the reflective object based on the time difference from emitting the test light to receiving the reflected light, and generate corresponding detection information accordingly. Figure 2 To explain the details of the detection information.

[0032] Figure 2 FIG. 1 is a schematic diagram of detection information generated by a distance measuring unit 10 according to an embodiment of the present invention. Figure 2In the figure, the horizontal axis shows that the reflected light received by the ranging unit 10 has different corresponding distance ranges due to covering different detection points of the target area, and the vertical axis shows the energy intensity of the reflected light received by the ranging unit 10 at the corresponding distance. Specifically, the ranging unit 10 may include an array composed of multiple single photon avalanche diodes (SPADs). Furthermore, the distance measuring unit 10 can sense the reflected light formed by the reflection of the test light, and divide the different distances corresponding to the reflected light into reflected light groups G1~G4 by the processor 11. The reflected light groups G1~G4 correspond to distance ranges D1~D4 respectively, wherein each distance range in the distance ranges D1~D4 is a distance range corresponding to multiple similar distances in the detection information. Further explanation, the distance ranges D1 and D2 are, for example, low-energy noise interference, the distance range D3 is, for example, the distance range from the distance measuring unit 10 to the projection screen, and the distance range D4 is, for example, the distance range from the distance measuring unit 10 to the wall behind the projection screen. The energy intensity of the distance range D4 is lower than the energy intensity of the distance range D3 due to the longer distance.

[0033] In some embodiments, the distance measuring unit 10 can select the reflected light that meets the set condition from the distance range D1 to D4 according to the set condition. Figure 2 The reflected light with energy intensity greater than the threshold is selected from the reflected light groups G1 to G4 as effective reflected light, thereby filtering out noise interference. The effective detection point corresponding to the effective reflected light is regarded as effective detection information and provided to the processor 11 for subsequent calculation. The effective detection point will be further described below.

[0034] Figure 3A It is a stereoscopic diagram of a projection device 1 according to the present invention emitting test light to a projection screen SCR (target region). Figure 3A , a projection device 1, a projection screen SCR and an obstacle OBJ are shown. In this embodiment, the projection screen SCR is used as the first reflection surface, and the obstacle OBJ is used as the second reflection surface. The first reflection surface is between the projection device and the second reflection surface. In other embodiments, the second reflection surface can be other objects with light reflection properties, and the second reflection surface can also be a flat surface or a curved surface. Please refer to Figure 3A Matching Figure 1, the distance measuring unit 10 of the projection device 1 can be used to emit test light in the direction of the projection screen SCR, and the test light is projected onto a plurality of different detection points A11-A15 on the projection screen SCR, and the reflected light reflected at the detection points A11-A15 is detected. In some embodiments, in addition to being projected onto the projection screen SCR, at least a portion of the test light will also penetrate the projection screen SCR and be projected onto the obstacle OBJ and be reflected by the obstacle OBJ, so that the distance measuring unit 10 detects the detection points B11-B15, wherein the detection points B11-B15 on the obstacle OBJ correspond to the detection points A11-A15 of the projection screen SCR, respectively. In this way, in addition to sensing the reflected light reflected by the detection points A11-A15 of the projection screen SCR, the distance measuring unit 10 will also sense the reflected light reflected by the detection points B11-B15 of the obstacle OBJ. Since the reflected light reflected by these detection points A11-A15, B11-B15 meets the set conditions, the detection points A11-A15, B11-B15 are regarded as valid detection points corresponding to the effective reflected light and are regarded as valid detection information. The processor 11 controls the first image projected by the optical machine 12 to be correctly presented on the projection screen SCR according to the valid detection information provided by the distance measuring unit 10. The first image is, for example, Figure 3A The image is composed of circles and triangles.

[0035] Please continue to refer to Figure 3A Matching Figure 1 ,exist Figure 3AIn the embodiment, the distance measuring unit 10 emits test light in the direction of the projection screen SCR and detects the reflected light, and five detection points A11 to A15 can be obtained, and B11 to B15 are the other five detection points obtained when a part of the test light penetrates the projection screen SCR and is reflected by the obstacle OBJ behind the projection screen SCR. Among them, the detection points A11, A12, and A13 are arranged in a line along a first direction (for example, the Y-axis direction), and the detection point A12 corresponds to the center of the projection screen SCR. The detection points A14 and A15 can be arranged in a line with the detection point A12 at the center along the second direction (for example, the Z-axis direction). The detection points B11, B12, and B13 correspond to the detection points A11, A12, and A13 arranged in a line along the first direction (for example, the Y-axis direction), and the detection points B14 and B15 can be arranged in a line with the detection point B12 at the center along the second direction (for example, the Z-axis direction). After determining that the reflected light reflected by the detection points A11, A12, A13, B11, B12, and B13 meets the set conditions, the distance measuring unit 10 can determine that the reflected light meeting the set conditions is the first effective reflected light, and the corresponding detection points A11, A12, A13, B11, B12, and B13 are determined as the first effective detection points. Similarly, the distance measuring unit 10 will also determine that the reflected light reflected by the detection points A14, A15 and B14, B15 is the effective reflected light after meeting the set conditions. The effective reflected light arranged along the Z-axis direction is regarded as the second effective reflected light, and the corresponding second effective detection points include A14, A12, A15 and B14, B12, and B15. Finally, the distance measuring unit 10 can regard the detection information related to the first effective detection point and the second effective detection point as effective detection information, and transmit it to the processor 11.

[0036] Specifically, after receiving the valid detection information provided by the ranging unit 10, the processor 11 can select at least three first valid detection points that form a line along the first direction on the same plane as the first selected detection points according to the first valid detection points of the valid detection information (for example, Figure 3A , the processor 11 selects the selected detection points as A11, A12, and A13 after judgment, and generates the first projection distance information based on these first selected detection points. Similarly, the processor 11 can also select at least three second detection points that form a line along the second direction on the same plane from the second effective detection points of the effective detection information as the second selected detection points (for example Figure 3A After judgment, the processor 11 selects the selected detection points as A14, A12, and A15), and generates second projection distance information based on these second selected detection points.

[0037] In some embodiments, the processor 11 may adjust the conditions for selecting the first selected detection point according to different system settings or environmental conditions. In some cases, the processor 11 may select at least three points from the first valid detection points that are completely parallel to the first direction and form a line as the first selected detection point, and the angle formed by the line connecting these points also presents a straight line arrangement of 180°. However, in some other cases, as the projection screen or the projection imaging surface may have some non-idealities such as bending or curvature (unevenness), the processor 11 may also adjust the conditions for selecting the first selected detection point to tolerate such non-idealities. For example, the direction of the arrangement of the first selected detection point selected by the processor 11 may not be completely parallel to the first direction, and may have an angle variation of, for example, plus or minus 5% with the first direction. In addition, as long as the angle formed by the line connecting any three or more first selected detection points falls within the range of 180°±5°, these first valid detection points may also be determined to be arranged in a straight line, and these detection points may be determined as the first selected detection points. The determination method of the second selected detection point is the same as that of the first selected detection point, so it will not be repeated.

[0038] In some embodiments, the processor 11 selects the first selected detection point (e.g., selected detection points A11, A12, A13) that is closest to the projection device 1, and generates the first projection distance information accordingly. In this embodiment, the first effective detection point obtained by the processor 11 is composed of three first effective detection points A11, A12, A13, or three first effective detection points B11, B12, B13, and the processor 11 selects the first effective detection points A11, A12, A13 that are closest to the projection device 1 as the first selected detection point, and generates the first projection distance information accordingly, so as to eliminate the interference of the obstacle OBJ behind the projection screen SCR on the distance measuring unit 10, so that the first image projected by the optical machine 12 to the projection screen SCR is within the effective focal length range of the projection device 1.

[0039] Similar to the process of the processor 11 determining the first projection distance information, the processor 11 can also extract the second effective detection point from the effective detection information, and determine whether the second effective detection point is composed of three second effective detection points A14, A12, A15, or composed of three second effective detection points B14, B12, B15. The processor 11 selects the second effective detection points A14, A12, A15 closest to the projection device 1 as the second selected detection point, so as to generate the second projection distance information according to the selected second selected detection point. Since the first projection distance information and the second projection distance information include the distance information of the projection screen SCR in the first and second directions, and the first direction and the second direction can be, for example, different directions on the YZ plane. In this embodiment, the first direction can be, for example, the Y-axis direction, and the second direction can be, for example, the Z-axis direction, and the first direction and the second direction are substantially perpendicular to each other. In this case, the processor 11 can obtain the projection surface distance information formed on the projection screen SCR in the first direction and the second direction according to the first projection distance information and the second projection distance information, so as to control the optical machine 12 to adjust the effective focal length range to the projection screen SCR.

[0040] In detail, Figure 3A In the embodiment, it is possible to determine whether the first effective detection points A11-A13 are arranged in a straight line along the first direction by using the angle ∠A11RA12 formed by the effective detection point A11, point R, and the effective detection point A12, the angle ∠A12RA13 formed by the effective detection point A12, point R, and the effective detection point A13, and the distance information of the first effective detection points A11-A13 included in the effective detection information.

[0041] Furthermore, the processor 11 can also generate first projection distance information of the projection screen SCR in the first direction and second projection distance information in the second direction for trapezoidal correction according to the effective detection information. Specifically, there may be projection image deformation caused by projection angle offset between the projection device 1 and the projection screen SCR. The processor 11 can perform trapezoidal correction according to the distance information corresponding to the first effective detection points A11, A12, A13 and the second effective detection points A14, A12, A15, and adjust the range of the first image projected by the optical machine 12 to eliminate the image deformation caused by the projection angle.

[0042] In detail, the processor 11 can determine the plane direction of the projection screen SCR based on the selected first selected detection point and the second selected detection point. Specifically, the processor 11 can obtain the first projection angle information (angle ∠A11RA13) of the projection screen SCR in the first direction based on the first distance information generated by the selected first selected detection points A11, A12, and A13, and obtain the second projection angle information (angle ∠A14RA15) of the projection screen SCR in the second direction based on the second distance information generated by the selected second selected detection points A14, A12, and A15. Further, the processor 11 can combine the first projection angle information and the second projection angle information to obtain the overall projection surface angle information of the projection screen SCR. In this way, the processor 11 can determine the plane direction of the projection screen SCR, and adjust the range of the first image projected by the optical machine 12 based on the projection surface angle information to eliminate the image deformation caused by the projection angle.

[0043] In some embodiments, in addition to the obstacle OBJ behind the projection screen SCR, there may also be sporadic obstacles on the front side of the projection screen SCR to interfere with the distance measurement operation of the distance measurement unit 10 on the projection screen SCR. In this case, the processor 11 can also make a judgment based on, for example, whether the energy intensity difference of the first effective reflected light meets the preset range. For example, when there are multiple obstacles between the projection screen SCR and the projection device 1 and the reflected lights corresponding to the multiple obstacles meet the set conditions, the processor 11 can determine whether the energy intensity of the reflected lights is uniform. When the processor 11 determines that the energy difference of any reflected light exceeds the preset range, the processor 11 can eliminate the effective detection points corresponding to the reflected lights, and select the selected detection points whose reflected energy difference falls within the preset range to generate the first projection distance information. In this way, the projection device 11 can effectively eliminate the interference caused by the distance measurement operation of the distance measurement unit 10 on the projection screen SCR when the obstacles on the front side of the projection screen SCR are accidentally arranged in a straight line in some unexpected situations. For example, the preset range can be, for example, the reflected energy difference within plus or minus 5% or 10%.

[0044] Figure 3B It is a stereoscopic diagram of a projection device 1 according to the present invention emitting test light to a projection screen SCR. Figure 3B Similar to Figure 3A The difference between the two is that there are more detection points corresponding to the four corners of the projection screen SCR. Figure 3B In the figure, there are nine detection points on the projection screen SCR and nine detection points on the obstacle OBJ, which can be regarded as three groups of valid detection points arranged along the first direction and each forming a line and three groups of valid detection points arranged along the second direction and each forming a line.

[0045] Please continue to refer to Figure 3B Matching Figure 1 ,exist Figure 3B In the embodiment, when the ranging unit 10 emits test light to the projection screen SCR and detects reflected light, the reflected light corresponding to the detection points A21~A29 of the projection screen SCR and the reflected light corresponding to the detection points B21~B29 of the obstacle OBJ can be obtained, and the ranging unit 10 determines them as valid detection points, thereby generating valid detection information about the valid detection points A21~A29, B21~B29 and providing it to the processor 11. The processor 11 can generate the first and second projection distance information based on the valid detection information to control the optical machine 12 to correctly present the first image on the projection screen SCR. In addition, the processor 11 can also generate the projection surface angle information based on the first and second projection distance information to control the optical machine 12 to perform more accurate trapezoidal correction. The above content about how the processor 11 adjusts the focal length of the optical machine 12 and performs trapezoidal correction based on the valid detection information has been described in detail above. Figure 3A In the paragraph, I will not go into details here.

[0046] In some embodiments, the processor 11 may first determine whether the first valid detection points A21-A23, B21-B23 are valid detection points arranged along the first direction and forming a line. However, in some scenarios, when an obstacle is set between the projection device 1 and the projection screen SCR, it will block part of the test light emitted to the projection screen SCR, so that the processor 11 cannot determine the existence of the first selected detection point arranged along the first direction and forming a line among the first valid detection points A21-A23, B21-B23. The processor 11 can also select other groups of valid detection points from another part of the test light to determine the first projection distance information. For example, the processor 11 can select the first valid detection points A26, A24, A27 for analysis, or the processor 11 can select the first valid detection points B26, B24, B27 for analysis. In this way, the processor 11 can generate the first projection distance information based on the first valid detection points of other groups.

[0047] Please continue to refer to Figure 3B Matching Figure 1 In some embodiments, the test light emitted by the distance measuring unit 10 and directed toward the corner of the projection screen SCR can be used to obtain a third detection point located at the corner of the projection screen SCR, and select the third effective detection point to assist in generating the third projection distance information. In this case, measuring the distance of the four corners of the projection screen SCR can enhance the rigor of determining the effective detection information.

[0048] Figures 4A to 4K Schematic diagrams of different situations when the projection device 1 performs distance measurement in an embodiment of the present invention, wherein Figure 4A to Figure 4KThe distance measuring unit 10 refers to Figure 1 The distance measuring unit 10 is not described in detail. Figure 4A In the process, the distance measuring unit 10 receives the reflected light of the detection points A1 to A3 on the projection screen SCR and the reflected light of the detection points B1 to B3 on the obstacle OBJ, and the detection points A1 to A3 on the projection screen SCR are replaced. Figure 3A The detection points A11 to A13 in the Figure 3B The detection points A21 to A23 in the figure, and the detection points B1 to B3 corresponding to the obstacle can be replaced Figure 3A The detection points B11 to B13 in the Figure 3B Detection points B21-B23 in the detection points. In this scenario, since the angle ∠A1A2A3 of the first effective detection points A1-A3, and the angle ∠B1B2B3 of the first effective detection points B1-B3 are substantially 180° or fall within the range of 180°±5°. Therefore, the processor 11 can determine the angle formed by the connecting lines of the two groups of first effective detection points by using the angle ∠A1PA2 formed by the effective detection point A1, point P, and the effective detection point A2, the angle ∠A2PA3 formed by the effective detection point A2, point P, and the effective detection point A3, and the angle ∠B1PB2 formed by the effective detection point B1, point P, and the effective detection point B2, and the angle ∠B2PB3 formed by the effective detection point B2, point P, and the effective detection point B3. Among the angles formed by the connecting lines of the two groups of first valid detection points, the processor 11 may select the group closest to the projection device 1 as the first selected detection point to generate the first projection distance information.

[0049] exist Figure 4B In the example, the distance measuring unit 10 obtains the reflected light of the first effective detection points A1 to A3 on the corresponding projection screen SCR, but only obtains the reflected light of the first effective detection points B1 and B3 on the corresponding obstacle OBJ, that is, the test light directed to the detection point A2 does not penetrate the projection screen SCR and is reflected by the obstacle OBJ. In this way, when the processor 11 determines whether there are first selected detection points arranged along the first direction and forming a line, the processor 11 will determine that the angle ∠A1A2A3 is approximately 180° or falls within the range of 180°±5°, but the angle ∠B1A2B3 is not, so the processor 11 will use the detection points A1, A2, and A3 as the first selected detection points, and generate the first projection distance information based on these first selected detection points.

[0050] exist Figure 4CIn the example, the test light emitted by the distance measuring unit 10 does not penetrate the positions corresponding to the first effective detection points A1 and A3 on the projection screen SCR, so the reflected light of the two detection points on the obstacle OBJ corresponding to the detection points A1 and A3 cannot be obtained. In this way, when the processor 11 determines whether there are first selected detection points arranged along the first direction and forming a line, the processor 11 will determine that the angle ∠A1A2A3 is approximately 180° or falls within the range of 180°±5°, but the angle ∠A1B2A3 is not, so the processor 11 will use the detection points A1, A2, and A3 as the first selected detection points, and generate the first projection distance information based on these first selected detection points.

[0051] exist Figure 4D In the example, the test light emitted by the distance measuring unit 10 does not penetrate the position corresponding to the first effective detection point A1 on the projection screen SCR, and therefore the reflected light of the detection point of the obstacle OBJ corresponding to the detection point A1 cannot be obtained. In this way, when the processor 11 determines whether there are first selected detection points arranged along the first direction and forming a line, the processor 11 will determine that the angle ∠A1A2A3 is substantially 180° or falls within the range of 180°±5°, but the angle ∠A1B2B3 is not, so the processor 11 will use the true detection points A1, A2, and A3 as the first selected detection points, and generate the first projection distance information based on these first selected detection points.

[0052] exist Figure 4E In the example, the first test light emitted by the distance measuring unit 10 does not penetrate the position corresponding to the first effective detection point A3 on the projection screen SCR, so the reflected light of the detection point of the obstacle OBJ corresponding to the detection point A3 cannot be obtained. In this way, when the processor 11 determines whether there are first selected detection points arranged along the first direction and forming a line, the processor 11 will determine that the angle ∠A1A2A3 is approximately 180° or falls within the range of 180°±5°, but the angle ∠B1B2A3 is not, so the processor 11 will use the detection points A1, A2, and A3 as the first selected detection points, and generate the first projection distance information based on these first selected detection points.

[0053] exist Figure 4FIn the example, the first test light emitted by the distance measuring unit 10 does not penetrate the positions corresponding to the first effective detection points A1 and A2 on the projection screen SCR, so the reflected light of the two detection points of the obstacle OBJ corresponding to the detection points A1 and A2 cannot be obtained. Only the test light emitted to the projection screen SCR penetrates the position corresponding to the first effective detection point A3, and the reflected light of the detection point B3 on the obstacle OBJ corresponding to the first effective detection point A3 is obtained. In this way, when the processor 11 determines whether there are first selected detection points arranged along the first direction and forming a line, the processor 11 will determine that the angle ∠A1A2A3 is approximately 180° or falls within the range of 180°±5°, but the angle ∠A1A2B3 is not. Therefore, the processor 11 will use the detection points A1, A2, and A3 as the first selected detection points, and generate the first projection distance information based on these first selected detection points.

[0054] exist Figure 4G In the example, the first test light emitted by the distance measuring unit 10 does not penetrate the positions corresponding to the first effective detection points A2 and A3 on the projection screen SCR, so the reflected light of the detection points of the obstacle OBJ corresponding to the detection points A2 and A3 is not obtained. Only the test light emitted to the projection screen SCR penetrates the projection screen SCR at the position corresponding to the first effective detection point A1, so the reflected light of the detection point B1 on the obstacle OBJ is obtained. In this way, when the processor 11 determines whether there are first selected detection points arranged along the first direction and forming a line, the processor 11 will determine that the angle ∠A1A2A3 is approximately 180° or falls within the range of 180°±5°, but the angle ∠B1A2A3 is not. Therefore, the processor 11 will use the detection points A1, A2, and A3 as the first selected detection points, and generate the first projection distance information based on the connection line of the first selected detection points.

[0055] exist Figure 4H In the embodiment, obstacles OBJ1-OBJ3 are located between the projection device 1 and the projection screen SCR. The distance measuring unit of the projection device 1 emits a test light to the position corresponding to the first effective detection point B1-B3 on the obstacles OBJ1-OBJ3, and part of the test light penetrates the obstacles to the projection screen SCR, so that the distance measuring unit obtains the reflected light of the first effective detection point A1-A3 on the projection screen SCR corresponding to the obstacles OBJ1-OBJ3. In this case, the processor 11 will determine that the angle ∠A1A2A3 is approximately 180° or falls within the range of 180°±5°, but the angle ∠B1B2B3 is not, so the processor 11 will use the detection points A1, A2, A3 as the first selected detection points, and generate the first projection distance information based on these first selected detection points.

[0056] exist Fig. 4IIn the projection device 1, only two obstacles OBJ2 and OBJ3 are located between the projection device 1 and the projection screen SCR. The distance measuring unit of the projection device 1 emits a test light to the position corresponding to the first effective detection points A1 to A3 on the projection screen SCR, but the test light is reflected by the obstacles OBJ2 and OBJ3, and the first effective detection points B2 and B3 are generated. In this case, the processor 11 will determine that the angle ∠A1A2A3 is approximately 180° or falls within the range of 180°±5°, but the angle ∠A1B2B3 is not, so the processor 11 will use the detection points A1, A2, and A3 as the first selected detection points, and generate the first projection distance information based on these first selected detection points.

[0057] exist Figure 4J , obstacles OBJ1-OBJ3 are located between the projection device 1 and the projection screen SCR. The distance measuring unit of the projection device 1 emits a test light to the positions of the obstacles OBJ1-OBJ3 corresponding to the first effective detection points B1-B3, and part of the test light penetrates the obstacles to the projection screen SCR, so that the distance measuring unit obtains the first effective detection points A1-A3 on the projection screen SCR corresponding to the positions of the obstacles OBJ1-OBJ3. In this case, the processor 11 will determine that the angle ∠A1A2A3 is approximately 180° or falls within the range of 180°±5°, but the angle ∠B1B2B3 is not, so the processor 11 will use the detection points A1, A2, A3 as the first selected detection points, and generate the first projection distance information based on these first selected detection points.

[0058] exist Figure 4K In the projection device 1, only two obstacles OBJ1 and OBJ3 are located between the projection device 1 and the projection screen SCR. The projection device 1 emits a test light to the positions corresponding to the obstacles OBJ1 and OBJ3 on the projection screen SCR. However, part of the test light is reflected by the obstacles OBJ1 and OBJ3, and the first effective detection points B1 and B3 are obtained corresponding to the obstacles OBJ1 and OBJ3. In addition, the distance measuring unit still obtains the reflected light of the detection points A1, A2, and A3 of the projection screen SCR. In this case, the processor 11 will determine that the angle ∠A1A2A3 is approximately 180° or falls within the range of 180°±5°, but the angle ∠B1A2B3 is not. Therefore, the processor will use the detection points A1, A2, and A3 as the first selected detection points, and generate the first projection distance information based on these first selected detection points.

[0059] Of course, in some cases, when obstacles OBJ1-OBJ3 are also arranged in a straight line along the first direction, and the processor 11 determines that the first effective detection points B1-B3 are also arranged along the first direction and form a line, the processor 11 can perform screening based on whether the energy intensity difference of the first effective reflected light meets the preset range. Since the energy difference of the reflected light reflected by obstacles OBJ1-OBJ3 is relatively large, the processor 11 can effectively exclude the first effective detection points B1-B3, and select the first effective detection points A1-A3 as the first selected detection points, and generate the first projection distance information accordingly.

[0060] Figure 5A The figure is a flow chart of a projection method according to an embodiment of the present invention. Figure 5A The projection method can be applied to Figure 1 The projection device 1. Figure 5A The projection method includes steps S511 to S513. In step S511, the distance measuring unit 10 can emit test light to the projection screen SCR, and detect the reflected light reflected by the test light to extract effective detection information, wherein a portion of the test light penetrates the projection screen SCR. In step S512, the processor 11 can receive the effective detection information from the distance measuring unit 10, and generate first projection distance information based on the effective detection information. In step S513, the processor 11 can control the image light beam projected by the optical machine 12 to the projection screen SCR based on the first projection distance information, so that the first image formed by the image light beam is within the effective focal length range of the projection device 1. For details about steps S511 to S513, please refer to the relevant paragraphs above, which will not be repeated here.

[0061] Figure 5B The figure is a flow chart of a projection method according to an embodiment of the present invention. Figure 5B The projection method can be applied to Figure 1 The projection device 1. Figure 5BThe projection method includes steps S521 to S526. In step S521, the distance measuring unit 10 may emit a test light to the projection screen SCR, wherein a portion of the test light penetrates the projection screen SCR. In step S522, the distance measuring unit 10 may detect the reflected light and extract the effective detection information. In step S523, the processor 11 may receive the effective detection information provided by the distance measuring unit 10, and generate the first projection distance information and the second projection distance information according to the effective detection information. In step S524, the processor 11 may generate the first projection angle information and the second projection angle information according to the first projection distance information and the second projection distance information. In step S525, the processor 11 may generate the projection surface distance information according to the first projection distance information and the second projection distance information, and generate the projection surface angle information according to the first projection angle information and the second projection angle information. In step S526, the processor 11 can control the optical machine 12 to project the image beam to the projection screen according to the projection surface distance information, so that the first image formed by the image beam can be located within the effective focal length range of the projection device, and control the optical machine 12 to perform keystone correction according to the projection surface angle information. For details of steps S521 to S526, please refer to the relevant paragraphs above, which will not be repeated here.

[0062] In summary, the projection device and projection method of the embodiments of the present invention have at least one of the following advantages: they can effectively eliminate the interference of obstacles in front of the projection screen on the distance measurement, and eliminate the material factors of the projection screen itself, so that the optical machine can correctly adjust the focal length range to the position of the projection screen.

[0063] As used herein, terms such as "substantially," "substantially," "substantially," and "approximately" are used to describe and take into account small variations. When used in conjunction with an event or circumstance, the above terms may refer to instances where the event or circumstance clearly occurred as well as instances where the event or circumstance closely approximates to occurring. For example, when used in conjunction with a numerical value, the terms may refer to a range of variation less than or equal to ±10% of the target numerical value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%. For example, two values ​​may be considered "substantially" the same or equal if the difference between them is less than or equal to ±10% of the average of the values ​​(e.g., less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%). For example, "substantially" parallel may refer to an angular variation of less than or equal to ±10° relative to 0°, such as less than or equal to ±5°, less than or equal to ±4°, less than or equal to ±3°, less than or equal to ±2°, less than or equal to ±1°, less than or equal to ±0.5°, less than or equal to ±0.1°, or less than or equal to ±0.05°. For example, "substantially" vertical may refer to an angular variation range of less than or equal to ±10° relative to 90°, such as less than or equal to ±5°, less than or equal to ±4°, less than or equal to ±3°, less than or equal to ±2°, less than or equal to ±1°, less than or equal to ±0.5°, less than or equal to ±0.1°, or less than or equal to ±0.05°.

[0064] However, the above is only a preferred embodiment of the present invention, and it cannot be used to limit the scope of the implementation of the present invention. That is, all simple equivalent changes and modifications made according to the claims and the content of the invention of the present invention are still within the scope of the patent of the present invention. In addition, any embodiment or claim of the present invention does not need to achieve all the purposes, advantages or features disclosed by the present invention. In addition, the abstract and title (invention name) are only used to assist in the retrieval of patent documents, and are not used to limit the scope of rights of the present invention. In addition, the terms "first", "second", etc. mentioned in this specification or claims are only used to name the name of the element or distinguish different embodiments or scopes, and are not used to limit the upper or lower limit on the number of elements.

Claims

1. A projection device for projecting onto a target area, characterized in that: The projection device includes an optical machine, a distance measuring unit and a processor, wherein: The optical machine is used to project an image beam to form a first image; The distance measuring unit is used to emit a test light to the target area, and to detect the reflected light formed by the reflection of the test light and extract effective detection information; and The processor is coupled to the distance measuring unit and the optical machine. A portion of the test light penetrates the target area, the processor is used to receive the effective detection information from the distance measuring unit, and to generate first projection distance information based on the effective detection information, and the processor is used to control the optical machine to project the image light beam toward the target area based on the first projection distance information, so that the first image corresponding to the image light beam is within the effective focal length range of the projection device.

2. The projection device according to claim 1, characterized in that: The distance measuring unit selects a plurality of first effective reflected lights and a plurality of first effective detection points corresponding to the reflected lights according to a set condition, wherein the effective detection information includes the plurality of first effective reflected lights and the plurality of first effective detection points corresponding to the reflected lights.

3. The projection device according to claim 2, characterized in that: The effective detection information received by the processor includes the multiple first effective detection points. The processor selects at least three first selected detection points arranged along the first direction on the same plane from the multiple first effective detection points, and generates the first projection distance information based on the at least three first selected detection points.

4. The projection device according to claim 3, characterized in that: The setting condition is whether the energy intensity of the reflected light is greater than a threshold to screen out the plurality of first effective reflected lights.

5. The projection device according to claim 3, characterized in that: When the processor determines that there are multiple first effective detection points arranged along the first direction on different planes, the processor selects at least three first selected detection points on the same plane whose energy intensity differences of the multiple first effective reflected lights are within a preset range, and generates the first projection distance information accordingly.

6. The projection device according to claim 3, characterized in that: When the processor determines that the energy intensity differences of the plurality of first effective reflected lights on different planes are within the preset range, the processor selects the at least three first selected detection points closest to the projection device, and generates the first projection distance information accordingly.

7. The projection device according to claim 3, characterized in that: The ranging unit also selects a plurality of second effective reflected lights from the reflected light according to set conditions to obtain a plurality of second effective detection points arranged along a second direction. The processor selects at least three second selected detection points from the plurality of second effective detection points that are in the same plane as the plurality of first effective detection points and arranged along the second direction, and generates the second projection distance information based on the at least three second selected detection points.

8. The projection device according to claim 7, characterized in that: The first direction is substantially perpendicular to the second direction.

9. The projection device according to claim 7, characterized in that: The distance measuring unit further selects a plurality of third effective reflected lights from the reflected light according to a set condition to obtain a plurality of third effective detection points located at the corners of the target area to assist in generating the third projection distance information.

10. The projection device according to claim 7, characterized in that: The processor also generates first projection angle information based on the at least three first selected detection points, and generates second projection angle information based on the at least three second selected detection points. The processor generates projection surface angle information projected onto the target area based on the first projection angle information and the second projection angle information.

11. The projection device according to claim 10, characterized in that: The processor performs keystone correction according to the projection surface angle information, the first projection distance information and the second projection distance information, so as to control the optical machine to perform projection accordingly.

12. The projection device according to claim 1, characterized in that: At least one effective reflected light among the plurality of first effective reflected lights screened by the distance measuring unit can obtain at least two first effective detection points.

13. A projection method for controlling the operation of a projection device, wherein the projection device comprises an optical machine, a distance measuring unit and a processor, wherein: The projection method comprises: The distance measuring unit emits a test light to a target area, and detects reflected light formed by the reflection of the test light and extracts effective detection information, wherein a part of the test light penetrates the target area; Receiving the effective detection information from the distance measuring unit by the processor, and generating first projection distance information according to the effective detection information; and The processor controls the optical machine to project an image beam toward the target area according to the first projection distance information, so that a first image formed corresponding to the image beam is located within the effective focal length range of the projection device.

14. The projection method according to claim 13, characterized in that: The projection method comprises: The distance measuring unit selects a plurality of first effective reflected lights and a plurality of first effective detection points corresponding to the reflected lights according to a set condition, wherein the effective detection information includes the plurality of first effective reflected lights and the plurality of first effective detection points corresponding to the reflected lights.

15. The projection method according to claim 14, characterized in that: The effective detection information received by the processor includes the plurality of first effective detection points, and the projection method includes: The processor selects at least three first selected detection points arranged along the first direction on the same plane from the plurality of first valid detection points, and generates the first projection distance information according to the at least three first selected detection points.

16. The projection method according to claim 15, characterized in that: The setting condition is whether the energy intensity of the reflected light is greater than a threshold to screen out the plurality of first effective reflected lights.

17. The projection method according to claim 15, characterized in that: The projection method comprises: When the processor determines that there are multiple first effective detection points arranged along the first direction on different planes, the processor selects at least three first selected detection points on the same plane whose energy intensity differences of the multiple first effective reflected lights are within a preset range, thereby generating the first projection distance information.

18. The projection method according to claim 15, characterized in that: The projection method comprises: When the processor determines that the energy intensity differences of the plurality of first effective reflected lights on different planes are within the preset range, the processor selects the at least three first selected detection points closest to the projection device to generate the first projection distance information.

19. The projection method according to claim 15, characterized in that: The projection method further comprises: Using the distance measuring unit to select a plurality of second effective reflected lights from the reflected light according to a set condition to obtain a plurality of second effective detection points arranged along a second direction; and The processor selects at least three second selected detection points from the plurality of second valid detection points, which are in the same plane as the plurality of first valid detection points and arranged along the second direction, and generates the second projection distance information according to the at least three second selected detection points.

20. The projection method according to claim 19, characterized in that: The first direction is substantially perpendicular to the second direction.

21. The projection method according to claim 19, characterized in that: The projection method further comprises: The distance measuring unit selects a plurality of third effective reflected lights from the reflected light according to a set condition to obtain a plurality of third effective detection points located at the corners of the target area to assist in generating the third projection distance information.

22. The projection method according to claim 19, characterized in that: The projection method further comprises: generating, by the processor, first projection angle information according to the at least three first selected detection points, and generating second projection angle information according to the at least three second selected detection points; and The processor generates projection surface angle information projected onto the target area according to the first projection angle information and the second projection angle information.

23. The projection method according to claim 22, characterized in that: The projection method comprises: The processor performs keystone correction according to the projection surface angle information, the first projection distance information and the second projection distance information, so as to control the optical machine to perform projection accordingly.

24. The projection method according to claim 13, characterized in that: The projection method comprises: At least two first effective detection points are obtained by using at least one effective reflected light among the plurality of first effective reflected lights screened by the distance measuring unit.

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