Projector control method and projector

Abstract

To simply correct a distortion of an output image projected on a projection surface.SOLUTION: A projector 10 includes a projection optical system 120 and a processing device 150. The processing device 150 arranges a plurality of correction points on a first side out of four sides of a rectangle correction image to be projected on a projection surface from the projection optical system 120. The processing device 150 receives an operation for moving a first correction point included in the plurality of correction points in a first direction. When a moving amount of the first correction point in the first direction is equal to or smaller than a predetermined threshold, the processing device 150 moves the first correction point in accordance with the operation. When the moving amount of the first correction point in the first direction exceeds the predetermined threshold, the processing device 150 moves correction points other than the first correction point in a second direction opposite to the first direction. The processing device 150 causes the projection optical system 120 to project an output image obtained by applying a distortion correction based on a moving amount and a moving direction of each of the multiple correction points to an input image.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a method for controlling a projector and a projector.

Background Art

[0002] When the projection light of the projector is incident obliquely on the projection surface which is the projection destination of the input image, the output image projected on the projection surface is distorted into a trapezoid. The projection light of the projector being incident obliquely on the projection surface means a state in which the normal line of the projection surface and the optical axis of the projector intersect. In conventional projectors, a correction image with correction points arranged in a grid pattern is projected onto the projection surface, and by moving each of these correction points arranged in a grid pattern, it was possible to correct the distortion caused by the projection light of the projector being incident obliquely on the projection surface (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In addition to the case where the projection light of the projector is incident obliquely on the projection surface, when there is a dent or protrusion on the projection surface, distortion occurs in the output image. In recent years, ultra-short focus projectors that can project a large image at a short projection distance have been proposed. 。 In an ultra-short focus projector, the distortion of the output image due to a dent or protrusion on the projection surface may become prominent. If a large number of correction points are arranged over the entire correction image, that is, if the density of the correction points in the correction image is increased, it becomes possible to arrange correction points at the position of the dent or protrusion on the projection surface, and it becomes possible to correct the distortion of the output image. However, the more the number of correction points arranged in the correction image increases, the more labor and time required for correction increase, and the correction work becomes complicated.

Means for Solving the Problem

[0005] The control method of the projector according to the present disclosure includes projecting, onto a projection surface, a corrected image in which a plurality of correction points are arranged on a first side among four sides of a rectangular corrected image projected from the projector onto the projection surface; receiving an operation of moving a first correction point included in the plurality of correction points in a first direction; moving the first correction point according to the operation when a moving amount of the first correction point in the first direction due to the operation is equal to or less than a predetermined threshold; moving correction points other than the first correction point among the plurality of correction points in a second direction opposite to the first direction when the moving amount exceeds the predetermined threshold; and projecting, onto the projection surface, an output image obtained by applying distortion correction based on the moving amount and moving direction of each of the plurality of correction points to an input image.

[0006] The projector according to the present disclosure includes a projection optical system and a processing device. The processing device projects, onto the projection surface, the corrected image in which a plurality of correction points are arranged on a first side among four sides of a rectangular corrected image projected from the projection optical system onto the projection surface; receives an operation of moving a first correction point included in the plurality of correction points in a first direction; moves the first correction point according to the operation when a moving amount of the first correction point in the first direction due to the operation is equal to or less than a predetermined threshold; moves correction points other than the first correction point among the plurality of correction points in a second direction opposite to the first direction when the moving amount exceeds the predetermined threshold; and causes the projection optical system to project an output image obtained by applying distortion correction based on the moving amount and moving direction of each of the plurality of correction points to an input image.

Brief Description of the Drawings

[0007]

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Embodiments for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The embodiments described below are technically preferably subject to various limitations. However, the embodiments of the present disclosure are not limited to the forms described below. 1. Embodiment

[0009] FIG. 1 and FIG. 2 are diagrams showing an example of the arrangement of the projector 10 according to an embodiment of the present disclosure with respect to the projection surface PS. More specifically, FIG. 1 is a perspective view of the room R in which the projector 10 is installed as seen from the ceiling direction. FIG. 2 is a perspective view of the room R as seen from the direction indicated by the arrow X in FIG. 1. As shown in FIGS. 1 and 2, in the present embodiment, one of the wall surfaces of the room R serves as the projection surface PS.

[0010] The projector 10 of the present embodiment is an ultra-short focus projector. As shown in FIGS. 1 and 2, the projector 10 is arranged on a table T arranged near the wall surface that serves as the projection surface PS. More specifically, as shown in FIGS. 1 and 2, the projector 10 is arranged on the left side and the lower side of the reference line BL. The reference line BL is the normal line of the wall surface passing through the center C of the wall surface that serves as the projection surface PS. In the present embodiment, the projector 10 is arranged in the room R with its optical axis directed toward the center C. That is, in the present embodiment, the projection light projected from the projector 10 onto the projection surface PS is incident obliquely on the projection surface PS from the lower left side.

[0011] The projection surface PS in the present embodiment is one of the wall surfaces of the room R and is not flat like a projection screen. That is, the projection surface PS has dents or protrusions in some places. When an image is projected from a conventional ultra-short focus projector onto such a non-flat projection surface PS, distortion due to the dents or protrusions of the projection surface PS occurs. The projector 10 of the present embodiment is configured to be able to easily correct not only the trapezoidal distortion caused by the projection light from the projector 10 being incident obliquely on the projection surface PS but also the distortion caused by the dents or protrusions of the projection surface PS.

[0012] FIG. 3 is a diagram showing a configuration example of the projector 10. As shown in FIG. 3, the projector 10 includes a communication device 100, an image processing device 110, a projection optical system 120, an input device 130, a storage device 140, and a processing device 150.

[0013] The communication device 100 is a device that communicates with other devices via a communication network such as a wired LAN (Local Area Network) or a wireless LAN. As a specific example of the communication device 100 in the mode of communicating with other devices via a wired LAN, there is a NIC (Network Interface Card) connected to the wired LAN via a LAN cable. Further, as a specific example of the communication device 100 in the mode of communicating with other devices via a wireless LAN, there are an antenna that receives communication radio waves in the wireless LAN and a circuit that modulates and demodulates the communication radio waves. As a specific example of other devices that communicate with the communication device 100 via the communication network, there is an image supply device that transmits image data representing an image projected from the projector 10 onto the projection surface PS to the projector 10. Hereinafter, the image data transmitted from the image supply device to the projector 10 is referred to as input image data. Further, the image represented by the input image data is referred to as an input image. The communication device 100 receives the input image data transmitted from the image supply device via the communication network. The communication device 100 outputs the received input image data to the image processing device 110. In the present embodiment, the case where the communication device 100 communicates with other devices via a wired LAN will be described, but it is not limited thereto. For example, the communication device 100 may be a USB (Universal Serial Bus) or an HDMI (High-Definition Multimedia Interface). Note that HDMI is a registered trademark.

[0014] The image processing device 110 is a device that performs image processing such as distortion correction on the input image data output from the communication device 100. This distortion correction includes correction of trapezoidal distortion caused by the projection light from the projector 10 incident obliquely on the projection surface PS, and correction of distortion caused by the depression or protrusion of the projection surface PS. The image processing device 110 executes distortion correction according to the correction data stored in the storage device 140. The correction data is data that defines the content of the distortion correction. Although details will be described later, the correction data is generated by the processing device 150. The image processing device 110 generates corrected image data by performing distortion correction according to the correction data on the input image data. The image processing device 110 outputs the corrected image data to the projection optical system 120. The image processing device 110 may be composed of a single processor. Also, a configuration in which a plurality of processors function as the image processing device 110 may be adopted. The image processing device 110 may be composed of a SoC (System on Chip) integrated with other circuits. A configuration in which all the functions of the image processing device 110 are implemented in hardware may be adopted, or all the functions of the image processing device 110 may be configured using a programmable device.

[0015] The projection optical system 120 is a device that projects the output image represented by the corrected image data output from the image processing device 110 onto the projection surface PS. As shown in FIG. 3, the projection optical system 120 includes a projection lens 121, a liquid crystal driving unit 122, a liquid crystal panel 123, and a light source unit 124. The liquid crystal driving unit 122 drives the liquid crystal panel 123 according to the corrected image data output from the image processing device 110, thereby drawing the output image represented by the corrected image data on the liquid crystal panel 123. The light source unit 124 includes a light source such as a halogen lamp or a laser diode, for example. The light from the light source unit 124 is modulated for each pixel in the liquid crystal panel 123 and projected onto the projection surface PS through the projection lens 121.

[0016] The input device 130 has a plurality of operators such as numeric keys. When an operation such as pressing is performed on the plurality of operators, the input device 130 gives operation content data indicating the content of the operation to the processing device 150. Thereby, the operation content of the user with respect to the input device 130 is transmitted to the processing device 150. The input device 130 may be configured to give the processing device 150 operation content data received from an external operation device such as a remote control.

[0017] The storage device 140 includes a RAM (Random Access Memory) which is a volatile storage device and a ROM (Read Only Memory) which is a non-volatile storage device. The non-volatile storage device stores a program P for causing the processing device 150 to execute a control method that prominently shows the features of the present disclosure. The volatile storage device is used by the processing device 150 as a work area when executing the program P.

[0018] Also, the volatile storage device stores attitude information indicating the attitude of the projection optical system 120 with respect to the projection surface PS. In the present embodiment, the user of the projector 10 inputs attitude information corresponding to the attitude of the projector 10 when the projector 10 is installed in the room R by an input operation on the input device 130. The storage device 140 stores the attitude information input by the input operation on the input device 130. In the present embodiment, as shown in FIGS. 1 and 2, the projector 10 is arranged in the room R on the left side and the lower side of the reference line BL with the optical axis facing upward to the right. Therefore, the projector 10 inputs attitude information indicating an upward-right attitude by an operation on the input device 130, and this attitude information is stored in the storage device 140.

[0019] The processing device 150 includes a processor such as a CPU (Central Processing Unit), that is, a computer. The processing device 150 may include one processor or a plurality of processors. The processing device 150 may be configured as a SoC integrated with a part or all of the storage device 140 and / or other circuits. Also, the processing device 150 may be configured by a combination of a CPU that executes a program and a DSP (Digital Signal Processor) that executes predetermined arithmetic processing. A configuration in which all functions of the processing device 150 are implemented in hardware may be adopted, or a configuration using a programmable device may be adopted. Further, the processing device 150 may also serve as the image processing device 110. That is, the processing device 150 may execute the functions of the image processing device 110. When the projector 10 is powered on, the processing device 150 reads the program P from the non-volatile storage device into the volatile storage device and starts executing the program P.

[0020] The processing device 150 operating according to the program P functions as the first projection control unit 151, reception unit 152, determination unit 153, first generation unit 154, second generation unit 155, and second projection control unit 156 shown in FIG. 3. That is, the first projection control unit 151, reception unit 152, determination unit 153, first generation unit 154, second generation unit 155, and second projection control unit 156 shown in FIG. 3 are software modules realized by operating a computer according to the program P. The functions of each of the first projection control unit 151, reception unit 152, determination unit 153, first generation unit 154, second generation unit 155, and second projection control unit 156 are as follows.

[0021] When an operation for instructing distortion correction is performed on the input device 130, the first projection control unit 151 causes the correction image G1 shown in FIG. 4 to be projected onto the projection optical system 120. The correction image G1 is an image for allowing the user to specify the position for correcting distortion and the content of the correction in the output image. As shown in FIG. 4, the outer extension of the correction image G1 is rectangular. A plurality of correction points for allowing the user to specify the position for correcting distortion and the content of the correction are arranged in the correction image G1. In the present embodiment, there are features in the arrangement of these plurality of correction points. Hereinafter, for comparison with the present embodiment, the correction image G2 in the distortion correction of a conventional projector will be described.

[0022] FIG. 5 is a diagram showing an example of the correction image G2. The correction image G2 is a rectangular image similar to the correction image G1. As shown in FIG. 5, correction points A1 to A4 are respectively arranged at the four corners, that is, the four vertices of the correction image G2. Also, correction points A5 to A8 are respectively arranged at the midpoints of the four sides of the correction image G2. A user of a conventional projector can specify the position for correcting distortion by designating one or more of the correction points A1 to A8. Also, a user of a conventional projector can specify the direction and amount of correction, that is, the content of the correction, by moving the designated correction points.

[0023] For example, when the correction image G2 that should originally be projected as a rectangle is projected onto the projection surface PS in a trapezoidal shape with the short side L2 being shorter than the short side L4, a user of a conventional projector can correct the trapezoidal distortion by moving each of the correction points A2 and A3 from the inside to the outside of the correction image G2 along the short side L2. Specifically, a user of a conventional projector can correct the trapezoidal distortion by moving the correction point A2 in a direction away from the correction point A6 along the short side L2 and moving the correction point A3 in a direction away from the correction point A6 along the short side L2.

[0024] In the case of trapezoidal distortion like this, it could be easily corrected even in a conventional projector. However, as shown in FIG. 6, when there is a distortion E1 that curves from the outside to the inside of the corrected image G2 in a part of the long side L1 of the corrected image G2, specifically, in the section from correction point A1 to correction point A5, due to a dent or the like on the projection surface PS, a conventional projector could not correct the distortion E1. This is because there are no correction points at the position of the distortion E1 in the corrected image G2. If the number of correction points arranged in the corrected image G2 is increased, it becomes possible to correct the distortion E1 even in a conventional projector. However, it is impossible to grasp in advance in which part of the corrected image G2 the distortion caused by the dent or protrusion of the projection surface PS occurs. For this reason, in order to enable correction of the distortion caused by the dent or protrusion of the projection surface PS in a conventional projector, it is necessary to evenly arrange a large number of correction points over the entire corrected image G2, resulting in a problem that the labor and time required for correction increase.

[0025] In the present embodiment, the first projection control unit 151 arranges correction points A1 to A4 at the four vertices of the corrected image G1, respectively. This is the same as in a conventional projector. In the present embodiment, in addition to the correction points A1 to A4, as shown in FIG. 4, correction points A5 to A11 are arranged in the corrected image G1 in the following manner. More specifically, the first projection control unit 151 first identifies, with reference to the attitude information, the vertex that is located farthest from the projection lens 121 when projected onto the projection surface PS among the four vertices of the corrected image G1. Then, the first projection control unit 151 arranges the correction points A5 to A11 on the long side of the two sides that are in contact with the identified vertex. This is because the two sides in contact with the vertex located farthest from the projection lens 121 are more likely to have distortion caused by a dent or protrusion of the projection surface PS than the two sides that are not in contact with the vertex, and the distortion of the long side is more likely to be noticeable than that of the short side. The long side in contact with the vertex located farthest from the projection lens 121 when the corrected image G1 is projected onto the projection surface PS is an example of the first side in the present disclosure. The long side and the short side that are not in contact with the vertex located farthest from the projection lens 121 are examples of the second side in the present disclosure.

[0026] When the attitude information indicates an upward-right attitude, among the four vertices of the corrected image G1, the vertex that is farthest from the projection lens 121 when projected onto the projection plane PS is the upper-right vertex. When the attitude information indicates a downward-right attitude, the vertex that is farthest is the lower-right vertex. When the attitude information indicates an upward-left attitude, the vertex that is farthest is the upper-left vertex. When the attitude information indicates a downward-left attitude, the vertex that is farthest is the lower-left vertex. In the present embodiment, since the attitude information stored in the storage device 140 indicates an upward-right attitude, the first projection control unit 151 specifies the upper-right vertex among the four vertices of the corrected image G1 as the vertex that is farthest. Then, as shown in FIG. 4, the first projection control unit 151 causes the projection optical system 120 to project a corrected image G1 in which correction points A5 to A11 are arranged on the long side L1 that is in contact with the vertex that is farthest from the projection lens 121 when projected onto the projection plane PS, in addition to the correction points A1 to A4. As is apparent from referring to FIG. 4, in the present embodiment, the number of correction points arranged on the long side L1 is larger than the number of correction points arranged on each of the short side L2, the long side L3, and the short side L4.

[0027] The user of the projector 10 can specify the position for distortion correction by designating one or more of the correction points A1 to A11 through an operation on the input device 130. The correction points designated by the user among the correction points A1 to A11 are an example of the first correction points in the present disclosure. The user of the projector 10 can specify the correction direction and the correction amount by moving the designated correction points through an operation on the input device 130. The moving direction specified by the operation on the input device 130 with respect to the designated correction point is an example of the first direction in the present disclosure. FIG. 7 is a diagram for explaining the directions in which the correction points can move. In FIG. 7, the directions in which the correction points can move are indicated by block arrows. As shown in FIG. 7, for the correction point A1 located at the upper left vertex of the corrected image G1, the user can move it in the direction from the inside to the outside or the reverse direction of the corrected image G1 along the axis orthogonal to the long side L1, and in the direction from the inside to the outside or the reverse direction of the corrected image G1 along the axis orthogonal to the short side L4. The same applies to each of the correction points A2 to A4. On the other hand, for the correction points arranged at positions different from the vertices, such as the correction points A5 to A11, the user can move them in the direction from the inside to the outside or the reverse direction of the corrected image G1 along the axis orthogonal to the side where the correction point is arranged. Hereinafter, for each of the correction points A5 to A11, the direction orthogonal to the long side L1 and from the inside to the outside of the corrected image G1 is referred to as the upward direction. The same applies to the correction points A1 and A2. Also, for each of the correction points A5 to A11, the direction orthogonal to the long side L1 and from the outside to the inside of the corrected image G1 is referred to as the downward direction. The same applies to the correction points A1 and A2. Note that in FIG. 7, the direction in which the correction point A5 can move is indicated by a block arrow.

[0028] FIG. 8 is a diagram showing an example of a corrected image G1 projected onto a projection surface PS having a depression or a protrusion. In the corrected image G1 shown in FIG. 8, similar to the corrected image G2 shown in FIG. 5, a distortion E1 that curves from the outside to the inside is generated in a part of the long side L1. In the corrected image G1 shown in FIG. 8, there is a correction point A6 at the position of the distortion E1. Therefore, the user of the projector 10 can correct the distortion E1 by designating the correction point A6 and moving the correction point A6 in a direction opposite to the direction of the distortion of the distortion E1, that is, upward, according to the magnitude of the distortion.

[0029] In the present embodiment, there are restrictions on the amount of movement of the correction points A1 to A11 by the movement operation, and the user can move the correction points A1 to A11 within the range of the restrictions. In the present embodiment, the shape of the output image on the projection surface PS is changed by changing the position where each pixel of the output image is drawn on the liquid crystal panel 123. Therefore, it is not possible to move beyond the range that can be drawn on the liquid crystal panel 123. As an example, in the present embodiment, the pixels on which the correction points A1 to A11 before correction are drawn are used as the reference positions. For each of the correction points A1 to A4, the threshold value is such that the maximum movement is 5 pixels in each of the upward, downward, and directions orthogonal to these directions from the reference position. For each of the correction points A5 to A11, the threshold value is such that the maximum movement is 5 pixels in each of the upward and downward directions.

[0030] For example, to correct the distortion E1 of the corrected image G1 shown in FIG. 8, the user of the projector 10 designates the correction point A6 and moves the correction point A6 in a direction opposite to the distortion E1, i.e., upward. However, as described above, since there is a threshold value for moving the correction point A6, even if the correction point A6 is moved to the upper limit threshold value where it can be moved, the distortion E1 may not be corrected. Thus, when the distortion E1 cannot be corrected by moving within the threshold value of the correction point A6, it becomes necessary to move the correction points A1, A2, and A5 to A11 downward, increasing the labor and time required for correction. Although details will be described later, in the present embodiment, when a movement exceeding the threshold value for movement at the correction points A1 to A11 is instructed, by moving other correction points other than the designated correction point in a second direction opposite to the first direction, an increase in the labor and time required for correction can be suppressed. For this reason, in the present embodiment, the movement of the correction points A1 to A11 is restricted.

[0031] The reception unit 152 receives, via the input device 130, a designation operation for designating each of the correction points A1 to A11 and a movement operation for moving the designated correction point. More specifically, the reception unit 152 executes the following processing each time it receives operation content data instructing the start of correction from the input device 130. First, as shown in FIG. 9, the reception unit 152 superimposes a cursor CR for designating and moving each of the correction points A1 to A11 on the corrected image G1 and projects it onto the projection optical system 120. When the reception unit 152 receives operation content data indicating an operation for moving the cursor CR from the input device 130, it moves the cursor CR according to the operation indicated by the received operation content data. When the reception unit 152 receives operation content data indicating an operation for determining the position of the cursor CR from the input device 130, it determines the correction point at which the cursor CR is located at the time of receiving the operation content data as the operation target correction point and erases the cursor CR. Next, when the reception unit 152 receives operation content data indicating a movement operation for the operation target correction point from the input device 130, it specifies the movement direction according to the operation content data.

[0032] The determination unit 153 determines whether or not the amount of movement of the specified correction point from the reference position is equal to or less than the above-described threshold value. In the present embodiment, this threshold value is 5 pixels. When the amount of movement of the correction point of the operation target from the reference position is equal to or less than the threshold value, for example, when the amount of movement is 3 pixels upward from the reference position, the determination result of the determination unit 153 is "Yes". Conversely, when the specified amount of movement with respect to the correction point of the operation target exceeds the threshold value, for example, when the amount of movement is 6 pixels upward from the reference position, the determination result of the determination unit 153 is "No". When the determination result by the determination unit 153 is "Yes", the movement of the correction point according to the movement operation and the generation of correction data according to the movement result are executed by the first generation unit 154. On the other hand, when the determination result by the determination unit 153 is "No", the movement of the correction point according to the movement operation and the generation of correction data according to the movement result are executed by the second generation unit 155.

[0033] The first generation unit 154 moves the correction point of the operation target by a predetermined amount in the direction specified by the movement operation, that is, the first direction, and generates correction data according to the movement result. In the present embodiment, the predetermined amount is 1 pixel, but it is not limited thereto. The second generation unit 155 moves all the other correction points located on the same side as the correction point of the operation target by a predetermined amount in the second direction opposite to the direction specified by the movement operation, and generates correction data according to the movement result. For example, if the direction specified by the movement operation is upward, the second direction is downward. Note that the amount of movement of all the other correction points by the second generation unit 155 may be the same, or may differ according to the distance from the correction point of the operation target. In the present embodiment, the former mode is adopted. Each of the first generation unit 154 and the second generation unit 155 stores the generated correction data in the storage device 140.

[0034] For example, as shown in FIG. 8, in a situation where distortion E1 occurs in a part of the long side L1 of the corrected image G1, correction point A6 is designated as the correction point to be operated on, and it is assumed that a user performs a moving operation to move correction point A6 upward. In this case, if the amount of movement upward from the reference position of correction point A6 specified by the moving operation is equal to or less than the threshold value, the determination result by determination unit 153 will be "Yes", and the movement of correction point A6 by first generation unit 154 will be executed. As a result, the corrected image G1 is updated as shown in FIG. 10. Note that in FIG. 10, the correction point that has moved according to the user's moving operation is shown in white, and the moving direction of the said correction point is indicated by an arrow.

[0035] Also, in the corrected image G1 shown in FIG. 8, correction point A6 is designated as the correction point to be operated on, a user performs a moving operation to move correction point A6 upward, and it is assumed that the amount of movement from the reference position of correction point A6 specified by the moving operation exceeds the threshold value. In this case, the determination result by determination unit 153 will be "No", and the second generation unit 155 will execute the movement of correction points A1, A2, A5, and A7 - A11 in the second direction, that is, downward movement. As a result, the corrected image G1 is updated as shown in FIG. 11. Also in FIG. 11, the correction point that has moved according to the user's moving operation is shown in white, and the moving direction of the said correction point is indicated by an arrow.

[0036] The second projection control unit 156 reads out the correction data stored in the storage device 140 and provides it to the image processing device 110. Thereafter, the image processing device 110 performs distortion correction corresponding to the correction data on the input image data provided from the communication device 100, and provides the corrected image data representing the input image with the distortion corrected to the projection optical system 120. Thereby, an output image to which distortion correction is applied to the input image is projected from the projection optical system 120 onto the projection surface PS.

[0037] In addition, the processing device 150 operating according to the program P executes a control method that prominently shows the features of the present disclosure. FIG. 12 is a flowchart showing the flow of this control method. As shown in FIG. 12, this control method includes a first projection control process SB100, a reception process SB110, a determination process SB120, a first generation process SB130, a second generation process SB140, and a second projection control process SB150. The processing contents of each of the first projection control process SB100, the reception process SB110, the determination process SB120, the first generation process SB130, the second generation process SB140, and the second projection control process SB150 are as follows.

[0038] In the first projection control process SB100, the processing device 150 functions as the first projection control unit 151. In the first projection control process SB100, the processing device 150 causes the projection optical system 120 to project the corrected image G1 shown in FIG. 4.

[0039] In the reception process SB110, the processing device 150 functions as the reception unit 152. In the reception process SB110, the processing device 150 receives, via the input device 130, a designation operation that designates any one of the correction points A1 to A11 as the correction point to be operated on, and a movement operation that moves the correction point designated by the designation operation.

[0040] In the determination process SB120, the processing device 150 functions as the determination unit 153. In the determination process SB120, the processing device 150 determines whether or not the amount of movement of the correction point designated by the movement operation from the reference position is equal to or less than the threshold value. If the amount of movement of the correction point designated by the movement operation from the reference position is equal to or less than the threshold value, the determination result of the determination process SB120 is "Yes". If the amount of movement of the correction point designated by the movement operation from the reference position exceeds the threshold value, the determination result of the determination process SB120 is "No".

[0041] When the determination result of the determination process SB120 is “Yes”, the first generation process SB130 is executed. In the first generation process SB130, the processing device 150 functions as the first generation unit 154. In the first generation process SB130, the processing device 150 first moves the correction point of the operation target in the specified direction and by the specified amount by a movement operation. Next, the processing device 150 generates correction data according to the movement result of the correction point of the operation target, and stores the generated correction data in the storage device 140.

[0042] When the determination result of the determination process SB120 is “No”, the second generation process SB140 is executed. In the second generation process SB140, the processing device 150 functions as the second generation unit 155. In the second generation process SB140, the processing device 150 moves all other correction points located on the same side as the correction point of the operation target in the direction opposite to the direction specified by the movement operation. Next, the processing device 150 generates correction data according to the movement results of all other correction points located on the same side as the correction point of the operation target, and stores the generated correction data in the storage device 140.

[0043] In the second projection control process SB150, the processing device 150 functions as the second projection control unit 156. In the second projection control process SB150, the processing device 150 reads out the correction data stored in the storage device 140 and provides it to the image processing device 110. Thereafter, the image processing device 110 performs distortion correction according to the correction data on the image data provided from the communication device 100 to generate corrected image data, and provides the generated corrected image data to the projection optical system 120. Thereby, an output image to which distortion correction is applied to the input image is projected from the projection optical system 120 onto the projection surface PS. For this reason, distortion caused by the depression or protrusion of the projection surface PS does not appear in the output image.

[0044] As described above, according to the present embodiment, it is possible to correct the distortion of the output image caused by the dent or protrusion of the projection surface PS without providing a large number of correction points over the entire corrected image G1. That is, according to the present embodiment, it is possible to correct the distortion of the output image caused by the dent or protrusion of the projection surface PS while suppressing an increase in the labor and time required for correction as compared with the mode of providing a large number of correction points over the entire corrected image G1.

[0045] 2. Modification The embodiment described above can be modified as follows. (1) In the above embodiment, more correction points are arranged on the long side of the two sides that contact the vertex that is farthest from the projection lens 121 when the corrected image G1 is projected onto the projection surface PS among the four vertices of the corrected image G1 than on the second side other than the two sides. However, more correction points may be arranged on the other side of the two sides that contact the vertex that is farthest from the projection lens 121, that is, the short side, than on the second side. This is because the distortion caused by the dent or protrusion of the projection surface PS is likely to appear on the short side of the two sides that contact the vertex that is farthest from the projection lens 121, following the long side that contacts the vertex. Note that the sides on which a plurality of correction points are provided in the corrected image G1 are not limited to the two sides that contact the vertex that is farthest from the projection lens 121 when the corrected image G1 is projected onto the projection surface PS, and may be the other two sides.

[0046] (2) In the above embodiment, the moving operation for the correction point A5 is an operation of moving the correction point A5 along the axis orthogonal to the long side L1 where the correction point A5 is located, and the same applies to the moving operation for each of the correction points A6 to A11. However, the moving operation for the correction point A5 only needs to be an operation of moving the correction point A5 along the axis intersecting the long side L1. For example, as shown in FIG. 13, it may be an operation of moving the correction point A5 along the axis AX1 passing through the position where the correction point A5 is arranged on the long side L1 and the center of the correction image G1. Similarly, for the moving operation for each of the correction points A6 to A11, it may be an operation of moving the correction point An along the axis passing through the position where the correction point An is arranged on the long side L1 and the center of the correction image G1. Note that n is any integer from 6 to 11.

[0047] (3) In the above embodiment, the predetermined amount when moving the correction point to be operated on was 1 pixel. However, the user may freely set the predetermined amount, and move the correction point to be operated on by the predetermined amount set by the user in the specified direction by the moving operation. Also, the predetermined amount in the first generation unit 154 and the predetermined amount in the second generation unit 155 may be set to different values. For example, the predetermined amount in the first generation unit 154 may be 1 pixel, and the predetermined amount in the second generation unit 155 may be 10 pixels. According to this aspect, up to 5 pixels where the movement amount from the reference position is below the threshold, the determination result of the determination unit 153 is "Yes", so the generation of correction data is executed by the first generation unit 154. After 6 pixels where the movement amount from the reference position exceeds the threshold, the determination result of the determination unit 153 is "No", so the generation of correction data is executed by the second generation unit 155. According to this aspect, it becomes possible to move the target correction point greatly with fewer operation procedures.

[0048] (4) In the above embodiment, the projector 10 is an ultra-short throw projector. However, the projector 10 may be a general projector that requires a longer projection distance to project a large image than an ultra-short throw projector. Even if the projector 10 is a general projector, by executing the control method of the present disclosure, it becomes possible to correct distortion of an output image caused by a dent or protrusion of the projection surface PS while suppressing an increase in the effort and time required for correction.

[0049] (5) In the above embodiment, the first projection control unit 151, the reception unit 152, the judgment unit 153, the first generation unit 154, the second generation unit 155, and the second projection control unit 156 are software modules, but may be hardware modules such as an ASIC (Application Specific Integrated Circuit). In addition, the three processes of the judgment process SB120, the first generation process SB130, and the second generation process SB140 in the above embodiment may be collectively referred to as a correction data generation process. In the above embodiment, the program P that causes the processing device 150 to execute the first projection control process SB100, the reception process, the correction data generation process, and the second projection control process SB150 is stored in advance in the storage device 140, but the program P may be manufactured separately or distributed for a fee or free of charge. As a specific method of distributing the program P, a mode in which the program P is written to a computer-readable recording medium such as a flash ROM (Read Only Memory) and distributed, or a mode in which the program P is distributed by downloading via a telecommunication line such as the Internet, may be considered. By operating a computer of a conventional projector according to the program P distributed in these embodiments, it becomes possible to cause the projector to execute the control method of the present disclosure.

[0050] 3. Aspects understood from the embodiments and modifications The present disclosure is not limited to the above-described embodiments and modifications, and can be realized in various modes without departing from the gist thereof. For example, the present disclosure can also be realized by the following modes. The technical features in the above embodiments corresponding to the technical features in each of the modes described below can be appropriately replaced or combined in order to solve some or all of the problems of the present disclosure or to achieve some or all of the effects of the present disclosure. Further, if the technical feature is not described as essential in this specification, it can be appropriately deleted.

[0051] One aspect of the method for controlling a projector according to the present disclosure includes the following first projection control process, Reception processing, and correction data generation process, and second projection control process. The first projection control process is a process of projecting a corrected image G1 of a rectangle from the projector 10 onto the projection surface PS. A plurality of correction points are arranged on a first side of the four sides of the corrected image G1. The reception process is a process of receiving a designation operation for designating a correction point to be operated among the plurality of correction points and a movement operation for moving the correction point designated by the designation operation in a first direction. The correction point to be operated is an example of the first correction point in the present disclosure. The correction data generation process includes a process of moving the first correction point according to the movement operation when the movement amount of the correction point by the movement operation is equal to or less than a predetermined threshold. Further, the correction data generation process includes a process of moving correction points other than the first correction point among the plurality of correction points in a second direction opposite to the first direction when the movement amount exceeds the predetermined threshold. The second projection control process is a process of projecting an output image obtained by applying distortion correction based on the movement amount and movement direction of each of the plurality of correction points to the input image onto the projection surface PS. According to this aspect, it is possible to easily correct the distortion of the output image projected on the projection surface PS.

[0052] In a more preferable control method of the aspect, the movement operation received in the reception process may be an operation of moving the first correction point along an axis intersecting the first side. According to this aspect, it is possible to correct the distortion of the first side in the direction along the axis intersecting the first side.

[0053] Also, one aspect of the projector of the present disclosure includes a projection optical system 120 and a processing device 150. The processing device 150 executes a first projection control process, a reception process, a correction data generation process, and a second projection control process for projecting a corrected image from the projection optical system 120 onto a projection surface PS. Also according to this aspect, it becomes possible to easily correct the distortion of the output image projected onto the projection surface PS.

Description of Signs

[0054] 10…Projector, 100…Communication device, 110…Image processing device, 120…Projection optical system, 130…Input device, 140…Storage device, 150…Processing device, 151…First projection control unit, 152…Reception unit, 153…Determination unit, 154…First generation unit, 155…Second generation unit, 156…Second projection control unit, P…Program, PS…Projection surface.

Claims

1. Projecting, onto the projection surface, a corrected image in which a plurality of correction points are arranged on a first side among four sides of a rectangular corrected image projected from a projector onto the projection surface; Receiving an operation of moving a first correction point included in the plurality of correction points in a first direction; When a movement amount of the first correction point in the first direction due to the operation is equal to or less than a predetermined threshold, moving the first correction point according to the operation; When the movement amount exceeds the predetermined threshold, moving correction points other than the first correction point among the plurality of correction points in a second direction opposite to the first direction, and Projecting, onto the projection surface, an output image obtained by applying distortion correction based on a movement amount and a movement direction of each of the plurality of correction points to an input image, wherein the operation is an operation of moving the first correction point along an axis intersecting the first side; A method for controlling a projector.

2. including a projection optical system and a processing device, wherein the processing device projects, onto the projection surface, the corrected image in which a plurality of correction points are arranged on a first side among four sides of a rectangular corrected image projected from the projection optical system onto the projection surface; receives an operation of moving a first correction point included in the plurality of correction points in a first direction; when a movement amount of the first correction point in the first direction due to the operation is equal to or less than a predetermined threshold, moves the first correction point according to the operation; when the movement amount exceeds the predetermined threshold, moves correction points other than the first correction point among the plurality of correction points in a second direction opposite to the first direction, and executes projecting, onto the projection optical system, an output image obtained by applying distortion correction based on a movement amount and a movement direction of each of the plurality of correction points to an input image, wherein the operation is an operation of moving the first correction point along an axis intersecting the first side; A projector.

Images