Output image adjustment device, projection device, and image adjustment method

Abstract

To provide an output image adjustment device, a projection device, and an image adjustment method that improves the measurement accuracy of points representing coordinates contained in a calibration image compared to when the points projected onto a projection area 34 are uniform in color.SOLUTION: An output image adjustment device 22 includes a projection unit 32 that projects a calibration image onto a projection area 34, the calibration image including a group of points representing coordinates in the X and Y directions, each point being the same type of color as adjacent points in the X direction and a different type of color from adjacent points in the Y direction, an imaging unit 30 that captures the calibration image projected onto the projection area 34, and an image adjustment unit 28 that adjusts the coordinates of the calibrated image projected by the projection unit 32 on the basis of the imaging data captured by the imaging unit 30.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to an output image adjustment device, a projection device, and an image adjustment method. [Background technology]

[0002] Patent Document 1 discloses a lighting system that includes a projector 1 and a camera 2, and in which a lighting control device projects and captures a stripe pattern whose brightness periodically changes in a first direction perpendicular to the light projection direction of the projection device, and associates the captured image with the projected image using a phase shift method for the first direction, and projects and captures a stripe pattern whose brightness periodically changes in a second direction perpendicular to the first direction, and associates the captured image with the projected image using a phase shift method for the second direction, thereby acquiring conversion information that determines the correspondence between pixels in the captured image and the projected image. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-271580 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure aims to provide an output image adjustment device, a projection device, and an image adjustment method that improve the measurement accuracy of points representing coordinates contained in a calibration image compared to when the color of the points projected onto the projection target is uniform. [Means for solving the problem]

[0005] An output image adjustment device of a first aspect of the present disclosure comprises a projection unit that projects a calibration image onto a projection target, the calibration image including a group of points representing coordinates in a first direction and a second direction intersecting the first direction, each of the points being the same type of color as adjacent points in the first direction and a different type of color than adjacent points in the second direction, an imaging unit that images the calibration image projected onto the projection target, and an image adjustment unit that adjusts the coordinates of the calibrated image projected by the projection unit based on the imaging data captured by the imaging unit.

[0006] According to the output image adjustment device of this aspect, a calibration image is projected in which each group of points representing coordinates is the same color in the first direction and adjacent points in the second direction are different colors, so that the image adjustment unit is less likely to misread the arrangement of the group of points from the captured data. Therefore, according to this output image adjustment device, the measurement accuracy of the points representing coordinates included in the calibration image is improved compared to when the points projected onto the projection target are of uniform color. Effect of the Invention

[0007] According to the present disclosure, it is possible to provide an output image adjustment device, a projection device, and an image adjustment method that improve the measurement accuracy of points representing coordinates contained in a calibration image compared to when the color of the points projected onto the projection target is uniform. [Brief description of the drawings]

[0008] [Figure 1] 1A and 1B are diagrams illustrating a state in which a projection device according to an embodiment of the present disclosure is used. [Diagram 2] FIG. 1 is a block diagram illustrating a configuration of a projection device according to an embodiment of the present disclosure. [Diagram 3] 3A to 3C are diagrams illustrating an image created by an image creating unit included in the projection device according to the first embodiment of the present disclosure. [Figure 4] 3A to 3C are diagrams illustrating imaging data captured by an imaging unit of a projection target according to the first embodiment of the present disclosure. [Diagram 5] 4 is a flow diagram illustrating an operation procedure of a CPU according to the first embodiment of the present disclosure. [Figure 6] 11A and 11B are diagrams illustrating an image created by an image creating unit included in a projection device according to a comparative example. [Figure 7] 11A and 11B are diagrams illustrating imaging data captured by an imaging unit of a projection target according to a comparative example. [Figure 8] 13A and 13B are diagrams illustrating an image created by an image creating unit included in a projection device according to a second embodiment of the present disclosure. [Figure 9] 13A to 13C are diagrams illustrating an image created by an image creating unit included in a projection device according to a third embodiment of the present disclosure. [Figure 10] 13A and 13B are diagrams illustrating an image created by an image creating unit included in a projection device according to another embodiment of the present disclosure. [Figure 11] 13A and 13B are diagrams illustrating an image created by an image creating unit included in a projection device according to another embodiment of the present disclosure. [Figure 12] 13A and 13B are diagrams illustrating an image created by an image creating unit included in a projection device according to another embodiment of the present disclosure. [Figure 13] FIG. 1 is a diagram of a color wheel illustrating hue angles. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an example of an embodiment of the present disclosure will be described with reference to the drawings. In each drawing, the same or equivalent components and parts are given the same reference numerals. In addition, the dimensional ratios of the drawings are exaggerated for the convenience of explanation and may differ from the actual ratios.

[0010] In each drawing, the arrow X direction is an example of a first direction of the present disclosure in image data to be described later, and the arrow Y direction is an example of a second direction of the present disclosure in image data to be described later. Note that in each drawing, the arrows X and Y are perpendicular to each other, but are not limited to this as long as the arrow X direction and the arrow Y direction are mutually intersecting directions.

[0011] In each drawing, the direction of the arrow X' is an example of a first direction of the present disclosure in imaging data, which will be described later, and the direction of the arrow Y' is an example of a second direction of the present disclosure in imaging data, which will be described later.

[0012] In addition, in this disclosure, lightness L, saturation S, and hue angle H (hue value) in image data refer to values ​​expressed by the following formulas (1) to (3). Note that R, G, and B shown in each formula are values ​​indicating the brightness of red, green, and blue at each pixel, respectively. Also, Max shown in each formula is a function indicating the maximum value among the values ​​in parentheses, and Min is a function indicating the minimum value among the values ​​in parentheses.

[0013]

number

[0014]

number

[0015]

number

[0016] As shown in formula (3), the hue angle H is not defined when the brightness of red, green, and blue are all equal, in other words, when it is black and white, including intermediate colors such as gray. In the following explanation, when referring to the hue angle H, the case where the brightness of red, green, and blue are all equal will not be taken into consideration. However, as shown in formulas (1) and (2), the lightness L and saturation S will also be taken into consideration when the brightness of red, green, and blue are all equal.

[0017] In this disclosure, the lightness L, hue angle H, and saturation S of the colors in each drawing are indicated as follows (see also FIGS. 3 to 4 and 6 to 13).

[0018] The lightness L is expressed by the thickness of the arrow shown inside the outline of the image. For example, if the arrow is thin, the lightness L is low (dark), and if the arrow is thick, the lightness L is high (bright).

[0019] The hue angle H is represented by the angle (direction) of the arrow shown inside the outline of the image, as shown in Figure 13. For example, if the arrow points to the right (0°), the color is red, if the arrow points to the upper left (120°), the color is green, and if the arrow points to the lower left (240°), the color is blue.

[0020] The saturation S is expressed by the type of line in the shaft of the arrow shown inside the outline of the image. More specifically, the shaft is a dashed line, and colors with large gaps (short solid lines) are low saturation colors (colors close to white, including gray, and black), and colors with small gaps (long solid lines) are high saturation colors (chromatic colors).

[0021] (composition) 1 is a diagram illustrating a state in which a projection device 20 according to the present disclosure is used. As an example, the projection device 20 according to the present disclosure is a so-called head-up display 10 that is disposed on a dashboard 14 of an automobile and projects onto a front windshield 16.

[0022] 1, the projection device 20 is disposed forward of the steering wheel 18 as seen by the driver of the vehicle, and projects an image toward a projection area 34 on the windshield 16. The projection area 34 is set in front of the driver as shown in FIG 1, and the driver can recognize necessary information as needed by reading the projected image on the windshield 16.

[0023] As an example, the front windshield 16 is curved in a direction expanding forward as seen by the driver. However, the shape of the curve of the front windshield 16 is not necessarily symmetrical in the longitudinal direction (vertical direction) and lateral direction (horizontal direction and depth direction) as seen by the driver, and may be distorted in either direction.

[0024] 2 is a block diagram illustrating a configuration of a projection device 20 according to the present disclosure. The projection device 20 according to the present disclosure includes an output image adjustment device 22 and an image creation unit 26. The output image adjustment device 22 also includes a control unit 24, a projection unit 32, an imaging unit 30, and an image adjustment unit 28.

[0025] The control unit 24 includes a CPU 24A (Central Processing Unit), which is an example of a processor, and a RAM 24B (Random Access Memory) used as a temporary work area for the CPU 24A. The control unit 24 also includes a non-volatile memory 24C that stores a control program for causing the control unit 24 to function, and an input / output interface (I / O) 24E. The CPU 24A, RAM 24B, non-volatile memory 24C, and I / O 24E are each connected via a bus 24D.

[0026] Furthermore, the CPU 24A of the control unit 24 reads the control program from the non-volatile memory 24C and executes the overall control of the projection device 20 which the control unit 24 is responsible for.

[0027] The non-volatile memory 24C is an example of a storage device that maintains stored information even if the power supplied to it is cut off, and is, for example, a semiconductor memory or a hard disk.

[0028] In addition, the projection unit 32, the imaging unit 30, the image adjustment unit 28, and the image creation unit 26 are connected to the I / O 24E.

[0029] The projection unit 32 is a device that projects image data created by the image creation unit 26 onto a projection area 34 on the front windshield 16 based on the operating procedure of a program executed by the CPU 24A. The projection unit 32 is, for example, a dot-matrix type liquid crystal projector that transmits white light emitted from a light source lamp through a liquid crystal panel, and each pixel has sub-pixels that transmit the respective colors of red, green, and blue. Each sub-pixel of the liquid crystal panel adjusts the brightness (luminance) of the transmitted light to project a color image onto the projection area 34. The image data will be described later.

[0030] The imaging unit 30 is a device that captures image data projected onto the projection area 34 by the projection unit 32 based on the operating procedure of a program executed by the CPU 24A.

[0031] Image adjustment unit 28 adjusts the image data created by image creation unit 26 based on the operating procedure of the program executed by CPU 24A. More specifically, image adjustment unit 28 is capable of adjusting the coordinates of pixels included in the image data, and adjusts the image projected by projection unit 32 by adjusting the coordinate values ​​of the image included in the image data based on the operating procedure executed by CPU 24A.

[0032] The image creation unit 26 creates image data based on the operation procedure of a program executed by the CPU 24 A. The image data created by the image creation unit 26 includes a calibration image, which will be described later.

[0033] 2, the image creation unit 26 and the image adjustment unit 28 may be executed by the same device or different devices as long as they are capable of creating image data and adjusting image data, respectively. In other words, the image creation unit 26 and the image adjustment unit 28 may both be functions of a program executed by the CPU 24A. In other words, the output image adjustment device 22 may be a function of another part of the projection device 20 excluding the image adjustment unit 28.

[0034] Next, a calibration image created by the output image adjustment device 22 according to the first embodiment of the present disclosure and the output image adjustment device 22 will be described with reference to FIG.

[0035] [First embodiment] The image creation unit 26 according to the present embodiment creates image data of the calibration image shown in FIG. 3. The calibration image includes a group of dot images, which are points representing coordinates in the horizontal direction and the vertical direction intersecting the horizontal direction, and each dot image has the same color as adjacent dot images in the horizontal direction and a different color from adjacent dot images in the vertical direction. In the following description, a dot image refers to an image of a point composed of several pixels (for example, two in the vertical direction and two in the horizontal direction, totaling four pixels). Also, as shown in FIG. 3, each dot image is arranged with a predetermined interval (for example, 20 pixels) between adjacent dot images in both the vertical and horizontal directions. Here, the projection area 34 of the front windshield 16 is an example of a projection target in the present disclosure. Also, the horizontal direction and the vertical direction are examples of a first direction and a second direction in the present disclosure.

[0036] The image creation unit 26 according to this embodiment creates the color format of the image data in the RGB888 format. That is, the color of each pixel in the image data is expressed by a numerical value of 256 gradations (00 to FF) for each of red, green, and blue. For example, when the color of each pixel is red, it is #FF0000, when it is green, it is #00FF00, and when it is blue, it is #0000FF.

[0037] In this embodiment, the calibration image includes two colors, for example, magenta (#FF00FF) and green (#00FF00). For example, if the color of any dot image is magenta, the color of the horizontally adjacent dot images is also magenta, and the color of the vertically adjacent dot images is green, i.e., different colors. Also, for example, if the color of any dot image is green, the color of the horizontally adjacent dot images is also green, and the color of the vertically adjacent dot images is magenta, i.e., different colors. Thus, in this embodiment, the same color and different colors are respectively considered to be "same type of color" and "different type of color".

[0038] In this embodiment, as shown in Fig. 3, the image data of the calibration image has all the dot images in the first row (dot images arranged in a horizontal line) in reddish purple, and all the dot images in the second row in green. Similarly, from the third row onwards, reddish purple dot images and green dot images are arranged alternately. In other words, in this embodiment, all the dot images in the odd-numbered rows are reddish purple, and all the dot images in the even-numbered rows are green.

[0039] In this embodiment, each dot image has the same saturation and lightness L. Therefore, in the calibration image in this embodiment, the dot images in the odd-numbered rows and the dot images in the even-numbered rows are separated by a hue angle H of 180° in the hue circle shown in FIG.

[0040] Incidentally, the projection area 34 of the front windshield 16, which is the projection target, and the optical system of the projection device 20 may be distorted as seen from the projection device 20. In this case, the image projected from the projection device 20 may be distorted from a rectangular shape as shown in FIG. 3 to a distorted shape as shown in FIG. 4. In other words, the dot image projected from the projection device 20 may be projected at a position different from the expected coordinates in the projection area 34. In FIG. 3, each dot image is given a code D1 followed by a number indicating a row (vertical order from the top in FIG. 3) and a number indicating a column (horizontal order from the left in FIG. 4). For example, D113 indicates the first dot image from the top and the third dot image from the left. In FIG. 4, each dot image is given a code corresponding to the dot image of the image data in FIG. 4 followed by a single quotation mark "'". For example, D113' indicates a dot image included in the imaging data when the dot image of D113 in FIG. 4 is imaged. Moreover, the dot images not indicated with reference numbers in FIG. 3 and FIG. 4 are also denoted with the same reference numbers.

[0041] Here, in the projection device 20 according to the present embodiment, the coordinates of the image data to be projected are adjusted based on the imaging data captured by the imaging device. The operation of the output image adjustment device 22 according to the first embodiment of the present disclosure and the coordinate adjustment procedure will be described with specific reference to Fig. 5.

[0042] (Coordinate adjustment procedure) The CPU 24A in this embodiment reads a program stored in the non-volatile memory 24C and executes the procedure shown in FIG.

[0043] First, in step S102, the CPU 24A causes the projection unit 32 to project a calibration image onto the projection area 34. Then, the CPU 24A proceeds to step S104.

[0044] Next, in step S104, the CPU 24A captures the projected calibration image and stores the captured image data of the calibration image in the RAM 24B. Then, the CPU 24A proceeds to step S106.

[0045] Next, in step S106, the CPU 24A judges whether or not the dot image to be measured is an odd-numbered row. For example, when the CPU 24A moves to step S106 for the first time after starting to execute the coordinate adjustment procedure, the CPU 24A judges that the dot image of the first row is to be acquired, and makes a positive judgment in step S106. If the CPU 24A judges in step S106 as positive, the CPU 24A moves to step S108. On the other hand, if the CPU 24A judges in step S106 as negative, the CPU 24A moves to step S110.

[0046] Next, in step S108, the CPU 24A sets so that a red-purple dot image will be acquired in a later step.Then, the CPU 24A proceeds to step S112.

[0047] In step S110, the CPU 24A sets so as to acquire a green dot image in a later step.Then, the CPU 24A proceeds to step S112.

[0048] Next, in step S112, the CPU 24A acquires the coordinate values ​​of one line of dot images included in the imaging data. More specifically, the CPU 24A acquires the line of dot images located at the position corresponding to the number of times S112 has been reached among the dot images included in the imaging data. For example, when the CPU 24A reaches S112 for the first time, since step S108 has been passed, the CPU 24A acquires the coordinate values ​​of the magenta dot images, which are the first line in the image data. Also, for example, when the CPU 24A reaches S112 for the second time, since step S110 has been passed, the CPU 24A acquires the coordinate values ​​of the green dot images, which are the second line in the image data. Then, the CPU 24A proceeds to step S114.

[0049] Next, in step S114, the CPU 24A determines whether the coordinates of all dot images included in the captured data have been acquired. If the CPU 24A determines in step S114 that the coordinates of all dot images included in the captured data have been acquired, the process proceeds to step S116. On the other hand, if the CPU 24A determines in step S114 that the coordinates of all dot images included in the captured data have been acquired, the process proceeds to step S106.

[0050] Next, in step S116, the CPU 24A adjusts the coordinates of the image data based on the coordinate values ​​of the dot images acquired in step S112. More specifically, the CPU 24A calculates the distance between the coordinate values ​​of the dot images of the imaging data acquired in step S116 and the coordinate values ​​of the dot images of the calibration image data for each dot image included in the calibration image data and the imaging data. Then, the CPU 24A adjusts the coordinate values ​​of each pixel included in the image data formed by the image creation unit 26 according to the distance calculated in step S116. In other words, the CPU 24A adjusts the coordinates of the calibrated image projected by the projection unit 32 based on the imaging data. After adjusting the coordinate values ​​of each pixel included in the image data, the CPU 24A ends the image adjustment procedure.

[0051] In each of the above steps, even if the color of the dot image included in the imaging data captured by the imaging unit 30 is different from the color of the dot image included in the calibration image, if the difference is within a predetermined threshold, the CPU 24A determines that the colors are the same. For example, if the color of the dot included in the calibration image is green (#00FF00) and the color of the dot in the imaging data is #00F000, the CPU 24A determines that these colors are the same. As an example, the predetermined threshold in this embodiment is up to 15 gradations in both positive and negative directions for each of red, green, and blue.

[0052] (Projection device 20 according to comparative example) 6 and 7 show a calibration image output by a projection device 20 according to a comparative example of this embodiment. As shown in Fig. 6 and Fig. 7, the projection device 20 according to the comparative example projects a white dot image as a calibration image, unlike the projection device 20 of this embodiment. In other words, in the projection device 20 according to the comparative example, the dot images are made to have the same color as adjacent dot images in both the vertical and horizontal directions.

[0053] In Fig. 6, each dot image is designated by D3 followed by a number indicating the row (vertical order from the top in Fig. 6) and column (horizontal order from the left in Fig. 6). For example, D313 indicates the first dot image from the top and the third from the left. In Fig. 7, each dot image is designated by a single quotation mark "'" followed by a code corresponding to the dot image in the image data in Fig. 6. For example, D313' indicates a dot image included in the imaging data when the dot image of D313 in Fig. 6 is imaged. Also, similar codes are to be used for dot images not designated by a code in Figs. 6 and 7.

[0054] Here, in the calibration image according to the comparative example, it may be difficult to determine which row a dot image belongs to. For example, the dot image indicated by D313' in FIG. 7 corresponds to the dot image located in the first row in FIG. 6, but is located lower in FIG. 7 than the dot image indicated by D322'. Therefore, in FIG. 7, if the dot image in the first row is counted as "the first row counted from the top in FIG. 7 (six dots in FIG. 7)", the dot image of D322' will be recognized as the first row, not the dot image of D313'. Similarly, if the dot image in the second row is counted as "the second row counted from the top in FIG. 7 (six dots from the seventh to the twelfth)", the dot image of D313' will be recognized as the dot image in the second row.

[0055] On the other hand, according to the projection device 20 of this embodiment, the following actions and effects can be obtained.

[0056] (Action and Effects) In the output image adjustment device 22 according to this embodiment, a calibration image is projected in which each group of dot images representing coordinates is horizontally made the same color, and vertically adjacent dot images are made different colors. Therefore, in the output image adjustment device 22 according to this embodiment, in step S112, the image adjustment unit 28 is less likely to misread the arrangement of the groups of dot images from the captured data. For example, the dot image indicated by D113' in FIG. 4 is located lower in FIG. 4 than the dot image indicated by D122'. However, in FIG. 4, by counting the dot image in the first row as "the first row of reddish purple images counting from the top in FIG. 4 (six dots in FIG. 4)", the dot image of D122', which is green, is not recognized as the dot image in the first row. Similarly, if the dot image in the second row is counted as "the first row of green images counting from the top in FIG. 4", the dot image of D113', which is reddish purple, is recognized as the dot image in the second row.

[0057] Therefore, according to the output image adjustment device 22, the measurement accuracy of the dot images representing the coordinates contained in the calibration image is improved compared to when the color of the dot images projected onto the projection target is uniform.

[0058] Furthermore, according to the output image adjustment device 22 of this embodiment, since the difference in hue angle H between vertically adjacent dot images is large, the image adjustment section 28 is less likely to misread the positions of the groups of dot images.

[0059] Therefore, according to this output image adjustment device 22, it becomes easier for the image adjustment section 28 to recognize groups of dot images of the same type based on the imaging data, compared to when the hue angle H between each dot image and its vertically adjacent dot image is small.

[0060] Furthermore, according to the projection device 20 of this embodiment, in the projection device 20 having an output image adjustment device 22 that captures a calibration image to be projected onto the projection target and adjusts the calibrated image, the detection accuracy of dot images representing coordinates contained in the calibration image is improved.

[0061] According to the image adjustment method of the present embodiment, a calibration image is projected in which each group of dot images representing coordinates is the same color in the horizontal direction and adjacent dot images in the vertical direction are different colors. Therefore, in the procedure of adjusting the calibrated image to be projected, it is difficult to misread the arrangement of the groups of dot images from the imaging data of the calibration image.

[0062] Therefore, according to this image adjustment method, the measurement accuracy of the dot images representing the coordinates contained in the calibration image is improved compared to when the color of the dot images projected onto the projection target is uniform.

[0063] Next, a calibration image created by the output image adjustment device 22 according to the second embodiment of the present disclosure and the output image adjustment device 22 will be described with reference to FIG.

[0064] [Second embodiment] 8 is a diagram showing a calibration image according to a second embodiment of the present disclosure. In this embodiment, unlike the first embodiment, the dot images are made to have the same color as adjacent dot images in the vertical direction and different colors from adjacent dot images in the horizontal direction.

[0065] In this embodiment, the coordinates of the imaging data obtained by imaging the calibration image projected onto the projection area 34 are acquired for each row. In other words, in this embodiment, the vertical and horizontal directions of the image data and imaging data are different from those of the first embodiment. Note that the other configurations and operations are the same as those of the first embodiment.

[0066] (Action and Effects) In this embodiment as well, the same actions and effects as those in the first embodiment can be obtained.

[0067] Next, a calibration image created by the output image adjustment device 22 according to the third embodiment of the present disclosure and the output image adjustment device 22 will be described with reference to FIG.

[0068] [Third embodiment] 9 is a diagram showing a calibration image according to a third embodiment of the present disclosure. In this embodiment, unlike the first embodiment, the dot images on the central side of the calibration image have a lower lightness L than the dot images on the outer sides of the calibration image.

[0069] In addition, the hue angle H in this embodiment is, for example, the same as that in the first embodiment. In other words, the dot image in this embodiment has a lightness L that is different from that of the dot image in the first embodiment. Other configurations and operations are the same as those in the first embodiment.

[0070] 1, the calibration image projected onto the front windshield 16 has a longer distance from the projection unit 32 to the projection target on the outside than on the center side. In other words, the calibration image projected onto the projection surface from the projection unit 32 is darker on the outside than on the inside.

[0071] (Action and Effects) Here, according to the output image adjustment device 22 of this embodiment, the central side of the image among the group of dot images has a lower luminance L than the outer side of the image. As a result, according to this output image adjustment device 22, the difference in luminance between the dot images on the central side of the image and the dot images on the outer side of the image becomes smaller, so that the range of luminance L captured by the imaging unit 30 can be narrowed. As a result, according to this output image adjustment device 22, it becomes easier to distinguish between the dot images of the calibration image and noise.

[0072] In this embodiment, the illuminance of the area on the projection target projected by the projection unit 32 may be homogenized based on the imaging data captured by the imaging unit 30. The CPU 24A may also detect dot defects (specific dot images not being colored) of the projection unit 32 based on the imaging data captured by the imaging unit 30.

[0073] In this case, in the output image adjustment device 22 that projects the calibration image onto the projection target, it becomes easier to find missing dots that occur in the projection unit 32 that outputs the calibration image based on the captured data.

[0074] In this embodiment, the luminance of the area on the projection target onto which the calibration image is projected is homogenized by adjusting the luminance L of the calibration image. Therefore, the output image adjustment device 22 according to this aspect does not require any other configuration for adjusting the luminance of the calibration image.

[0075] In this embodiment, the same actions and effects as those in the first embodiment can be obtained.

[0076] In this embodiment, the method of homogenizing the illuminance of the area on the projection target where the calibration image is projected is not limited to this. For example, a filter may be provided in the projection unit 32 so that the inside of the projection area becomes dark, and the brightness L of each dot image of the calibration image may be made equal. Even in this case, it is possible to obtain the effect of making it easier to distinguish between the dot images of the calibration image and noise.

[0077] [Other embodiments] In the above-described embodiment, an example in which the hue angle H or the lightness L is different is shown, but the embodiment according to the present disclosure is not limited to this. That is, in this embodiment, if one of the dot images adjacent to each other in the vertical or horizontal direction has the same color and the other has multiple colors, the same action and effect as the above-described embodiment can be obtained.

[0078] In other words, in the output image adjustment device 22 and the projection device 20 according to the present disclosure, points of the same type of color and points of different types of colors may be points that differ by a predetermined threshold or more in at least one of the hue angle H, saturation S, and lightness L. In other words, different types of colors refer to points that differ in the hue angle H, saturation S, or lightness L.

[0079] For example, Fig. 10 is a diagram showing a calibration image according to another embodiment of the present disclosure. In the calibration image shown in Fig. 10, unlike the first embodiment, the colors of the dot images in the odd-numbered rows are warm colors, and the colors of the dot images in the even-numbered rows are cool colors. In other words, in this embodiment, the warm colors and the cool colors are the same type of colors and different types of colors, respectively.

[0080] In this embodiment, the colors of the dot images in the odd-numbered rows and the colors of the dot images in the even-numbered rows are at least a predetermined value apart in terms of the hue angle H. That is, in the example of Fig. 10, the predetermined threshold value corresponds to a predetermined value being the difference in the hue angle H.

[0081] In addition, in the example of Fig. 10, the lightness L and saturation S of each dot image are not limited. In other words, in the example of Fig. 10, the dot images in odd-numbered rows and the dot images in even-numbered rows may have the same lightness L or saturation S. Other configurations and operations are the same as those of the first embodiment.

[0082] 11 is a diagram showing a calibration image according to another embodiment of the present disclosure. In the calibration image shown in FIG. 11, unlike the first embodiment, the colors of the dot images in odd-numbered rows are chromatic, and the colors of the dot images in even-numbered rows are achromatic. In other words, in this embodiment, the colors are the same type and different types, respectively, depending on the difference in saturation S.

[0083] 11, there are no limitations on the lightness L and hue angle H of each dot image. In other words, the lightness L or hue angle H of the dot images in the odd-numbered rows and the dot images in the even-numbered rows may be the same.

[0084] In this embodiment, the colors of the dot images in the odd-numbered rows and the colors of the dot images in the even-numbered rows differ in saturation S by at least a predetermined value. That is, in the example of Fig. 11, the predetermined threshold value corresponds to the difference in saturation S being a predetermined value.

[0085] 12 is a diagram showing a calibration image according to another embodiment of the present disclosure. In the calibration image shown in FIG. 12, unlike the first embodiment, the colors of the dot images in odd-numbered rows are bright, and the colors of the dot images in even-numbered rows are dark. In other words, in this embodiment, the difference in lightness L results in the same type of color and different types of color.

[0086] 12, the saturation S and hue angle H of each dot image are not limited. In other words, the dot images in the odd-numbered rows and the dot images in the even-numbered rows may have the same saturation S or hue angle H.

[0087] In this embodiment, the color of the dot images in the odd-numbered rows and the color of the dot images in the even-numbered rows differ in lightness L by at least a predetermined value (%) from the maximum value (255 in this embodiment). That is, in the example of Fig. 12, the predetermined threshold value corresponds to the difference in lightness L being a predetermined value (%) from the maximum value.

[0088] (Action and Effects) In this embodiment, points of different colors differ from vertically adjacent points by a predetermined threshold or more in at least one of the hue angle H, saturation S, and lightness L. This allows the image adjustment unit 28 to determine whether points are the same type or different types by detecting a difference in at least one of the hue angle H, saturation S, and lightness L of the points from the imaging data, making it less likely that the arrangement of the groups of points will be misread from the imaging data.

[0089] Therefore, according to this output image adjustment device 22, the measurement accuracy of points representing coordinates contained in the calibration image is improved for the color difference between the colors of points of the same type and the colors of points of different types, compared to when the hue angle H, saturation S, and lightness L are each less than a predetermined threshold value.

[0090] (Other variations) As in the above embodiment, the procedure of projecting a calibration image and adjusting the coordinates of the calibrated image may be performed at any time. For example, it may be performed when the projection device 20 is shipped, or when a vehicle equipped with the projection device 20 is shipped, or it may be performed by an operator or a user at any time to adjust the image projected on the front windshield 16.

[0091] In the above description, the calibration image is directly projected onto the windshield 16, but this is not limiting, and the image may be adjusted by preparing another projection target for calibration and projecting the image onto the other projection target. For example, the calibration image may be output while the windshield 16 is covered from the outside with a blackout curtain so that the imaging unit 30 can easily read the dot image.

[0092] In the above description, the dot images are arranged at predetermined intervals between adjacent dot images as points representing coordinates, but the technology according to the present disclosure is not limited to this. For example, the dot images may be arranged continuously with adjacent dot images and may be linear when viewed macroscopically. More specifically, the dot images may be a lattice-like image composed of a group of lines extending in a first direction and arranged at intervals in a second direction, and a group of lines extending in the second direction and arranged at intervals in the first direction. In this case, the intersections of the lines can be used as points representing coordinates to obtain the same effects and advantages as those described above. In addition, by making the dot images linear when viewed macroscopically, it becomes easier to find the projection area 34 of the projection target and the distortion of the optical system of the projection device 20.

[0093] In the above description, the colors of the dot images in the odd-numbered and even-numbered rows are different, but the technology according to the present disclosure is not limited to this. For example, the color of the dot images in the first, fourth, seventh, etc. rows may be red, the color of the dot images in the second, fifth, eighth, etc. rows may be green, and the color of the dot images in the third, sixth, ninth, etc. rows may be blue. In this case, the colors of each type may be repeated periodically or may be selected randomly, as long as they are different from the colors of the adjacent points in the second direction.

[0094] In addition, the processing executed by the CPU 24A by reading the software (program) in each of the above embodiments may be executed by various processors other than the CPU 24A. In this case, examples of the processor include a PLD (Programmable Logic Device) such as an FPGA (Field-Programmable Gate Array) whose circuit configuration can be changed after manufacture, and a dedicated electric circuit such as an ASIC (Application Specific Integrated Circuit) which is a processor having a circuit configuration designed exclusively for executing a specific processing. In addition, the processing may be executed by one of these various processors, or may be executed by a combination of two or more processors of the same or different types (for example, a plurality of FPGAs, a combination of a CPU and an FPGA, etc.). In addition, the hardware structure of these various processors is, more specifically, an electric circuit that combines circuit elements such as semiconductor elements.

[0095] In addition, in each of the above embodiments, the processing program is pre-stored (installed) in the non-volatile memory 24C, but the present invention is not limited to this. The program may be provided in a form stored in a non-transitory storage medium such as a CD-ROM (Compact Disk Read Only Memory), a DVD-ROM (Digital Versatile Disk Read Only Memory), or a USB (Universal Serial Bus) memory. The program may also be downloaded from an external device via a network.

[0096] The above describes an embodiment of the present disclosure with reference to the attached drawings. However, it is clear that a person with ordinary knowledge in the technical field to which the present disclosure pertains can conceive of various modified examples or application examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure.

[0097] Furthermore, preferred aspects of the present disclosure will be described below.

[0098] (Appendix 1) a projection unit that projects a calibration image onto a projection target, the calibration image including a group of points representing coordinates in a first direction and a second direction intersecting the first direction, the group of points being colored in the same type as adjacent points in the first direction and colored in a different type than adjacent points in the second direction; an imaging unit that captures the calibration image projected onto a projection target; an image adjustment unit that adjusts coordinates of a calibrated image projected by the projection unit based on imaging data captured by the imaging unit; An output image adjustment device comprising:

[0099] (Appendix 2) The different color points are points that differ from adjacent points in the second direction in at least one of hue, saturation, and brightness by a predetermined threshold or more. 2. An output image adjustment device as described in claim 1.

[0100] (Appendix 3) The central side of the calibration image has a lower brightness than the outer side of the calibration image. 3. An output image adjustment device according to claim 1 or 2.

[0101] (Appendix 4) An output image adjustment device according to any one of Supplementary Note 1 to Supplementary Note 3; an image creation unit for creating the calibrated image; A projection device comprising:

[0102] (Appendix 5) a step of projecting, onto a projection target, a calibration image including a group of points representing coordinates in a first direction and a second direction intersecting the first direction, each of the points being colored in the same type as adjacent points in the first direction and in a different type of color than adjacent points in the second direction; capturing the calibration image projected onto a projection target; adjusting the coordinates of the calibrated image to be projected based on the captured image data of the calibration image; The image adjustment method includes:

[0103] (Appendix 6) a projection unit that projects a calibration image extending in a first direction and a second direction intersecting the first direction onto a projection target; an imaging unit that captures the calibration image projected onto a projection target; an image adjustment unit that homogenizes the illuminance of an area of ​​the projection target onto which the projection unit projects, based on the imaging data captured by the imaging unit, and detects coordinates of a pixel of the projection unit that has a missing dot, based on the imaging data captured by the imaging unit; An output image adjustment device comprising:

[0104] (Appendix 7) the image adjustment unit adjusts the brightness of the calibration image to homogenize the illuminance of the region on the projection target onto which the calibration image is projected; 7. An output image adjustment device as described in appendix 6.

[0105] (Appendix 8) An output image adjustment device according to claim 6 or 7; an image creation unit that creates the calibration image; A projection device comprising:

[0106] (Appendix 9) projecting a calibration image extending in a first direction and a second direction intersecting the first direction onto a projection target; capturing the calibration image projected onto a projection target; a step of homogenizing illuminance in an area of ​​the projection target onto which the calibration image is projected based on the captured image data; detecting coordinates of a pixel having a missing dot included in the calibration image based on the imaging data; The image adjustment method includes: [Explanation of symbols]

[0107] 10 Head-up display 14 Dashboard 16 Front Windshield 18 Steering Wheel 20 Projection device 22 Output image adjustment device 24 Control Unit 26 Image Creation Department 28 Image Adjustment Section 30 Imaging unit 32 Projection section 34 Projection area (example of projection target) 24A CPU 24B RAM 24C Non-volatile memory 24D Bus 24E Input / Output Interface

Claims

1. a projection unit that projects a calibration image onto a projection target, the calibration image including a group of points representing coordinates in a first direction and a second direction intersecting the first direction, the group of points being colored in the same type as adjacent points in the first direction and colored in a different type than adjacent points in the second direction; an imaging unit that captures the calibration image projected onto a projection target; an image adjustment unit that adjusts coordinates of a calibrated image projected by the projection unit based on imaging data captured by the imaging unit; An output image adjustment device comprising:

2. The different color points are points that differ from adjacent points in the second direction in at least one of hue, saturation, and brightness by a predetermined threshold or more.

2. The output image adjustment device according to claim 1.

3. The central side of the calibration image has a lower brightness than the outer side of the calibration image.

2. The output image adjustment device according to claim 1.

4. An output image adjustment device according to any one of claims 1 to 3; an image creation unit for creating the calibrated image; A projection device comprising:

5. a step of projecting, onto a projection target, a calibration image including a group of points representing coordinates in a first direction and a second direction intersecting the first direction, each of the points being colored in the same type as adjacent points in the first direction and in a different type of color than adjacent points in the second direction; capturing the calibration image projected onto a projection target; adjusting the coordinates of the calibrated image to be projected based on the captured image data of the calibration image; 23. An image adjustment method comprising:

Images