JP2014199385A - Display device and display method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve visibility by correcting distortion of a display image in the case of horizontal movement of viewer's viewpoint position and to suppress the increase in cost of components.SOLUTION: An HUD device 100 includes a ROM 22 in which a first distortion correction parameter for the case that a viewpoint position of a driver 102 is at the left end of a viewable range for a display image F, a second distortion correction parameter for the case that the viewpoint position is at the center of the viewable range, and a third distortion correction parameter for the case that the viewpoint position is at the right end of the viewable range are stored. A control unit 20 acquires one of the first to third distortion correction parameters on the basis of the viewpoint position or computes an interpolated distortion correction parameter by interpolation processing between two of the first to third distortion correction parameters and corrects distortion of the display image F projected on a windshield 101 on the basis of one of the first to third distortion correction parameters or the interpolated distortion correction parameter.

Description

  The present invention relates to a display device and a display method thereof.

  A so-called head-up display device (hereinafter referred to as a HUD device) is known as a display device that displays information to a driver of a vehicle such as a conventional automobile. The HUD device projects a display image displayed on a display unit such as a liquid crystal display panel onto a projection target unit such as a windshield so that a driver can visually recognize a virtual image of the display image.

  In the HUD device, a display image is distorted by enlarging the display image by an optical system such as a projection target or a concave mirror. Since the visibility decreases when the display image is distorted, a technique for correcting the distortion by deforming the display image in advance reversely is known (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 10-149085 JP 2007-158923 A

  The technique disclosed in Patent Literature 1 can display a display image without distortion when the viewpoint position of the driver is the design reference position, but when the viewpoint position of the driver moves left and right. Since the distortion is different from the design reference position, there is a problem that the display image is distorted. On the other hand, for example, Patent Document 2 discloses a method for correcting distortion of a display image based on the viewpoint position of an observer. However, in such a method, it is conceivable to store distortion correction parameters for correcting distortion of a display image in a plurality of storage devices in accordance with the viewpoint position. However, if the capacity of the distortion correction parameters increases, the component cost increases. There was still room for improvement.

  Therefore, the present invention solves the above-described problems, corrects the distortion of the display image even when the observer's viewpoint position moves to the left and right, improves visibility, and suppresses an increase in component costs. It is an object of the present invention to provide a display device and a display method thereof.

In order to solve the above problems, the display device of the present invention includes a display means for displaying a display image,
Display control means for displaying the display image on the display means;
A position detecting means capable of detecting an observer's viewpoint position, and projecting the display image onto a projection target member,
A first distortion correction parameter when the viewpoint position is the left end of the visible range of the display image; a second distortion correction parameter when the viewpoint position is the center of the visible range of the display image; A third distortion correction parameter when the viewpoint position is the right end of the visible range of the display image;
The display control means acquires one of the first to third distortion correction parameters based on the viewpoint position, or performs an interpolation process between two of the first to third distortion correction parameters. And calculating an interpolation distortion correction parameter to correct the distortion of the display image when projected onto the projection member based on any of the first to third distortion correction parameters or the interpolation distortion correction parameter. It is characterized by doing.

In order to solve the above problems, a display method of a display device of the present invention includes a display unit that displays a display image;
A position detection means capable of detecting a viewer's viewpoint position, and a display device display method for projecting the display image onto a projection target member,
A first distortion correction parameter when the viewpoint position is the left end of the visible range of the display image; a second distortion correction parameter when the viewpoint position is the center of the visible range of the display image; A third distortion correction parameter when the viewpoint position is the right end of the visible range of the display image;
Either one of the first to third distortion correction parameters is acquired based on the viewpoint position, or interpolation processing is performed by interpolating between two of the first to third distortion correction parameters. Calculating a parameter, and correcting distortion of the display image when projected onto the projection member based on any of the first to third distortion correction parameters or the interpolation distortion correction parameter. To do.

In order to solve the above problems, the display device of the present invention includes a display means for displaying a display image,
Display control means for displaying the display image on the display means;
A position detecting means capable of detecting an observer's viewpoint position, and projecting the display image onto a projection target member,
A first distortion correction parameter when the viewpoint position is at the upper end and the left end of the viewable range of the display image, and a second when the viewpoint position is at the upper end and the left and right center of the viewable range of the display image A distortion correction parameter, a third distortion correction parameter when the viewpoint position is the upper end and the right end of the viewable range of the display image, and the viewpoint position is the upper and lower center and the left end of the viewable range of the display image. The fourth distortion correction parameter in the case, the fifth distortion correction parameter in the case where the viewpoint position is the vertical center and the horizontal center of the display image viewable range, and the viewpoint position is the viewable range of the display image. And a seventh distortion correction parameter when the viewpoint position is the lower end and the left end of the viewable range of the display image. A meter, an eighth distortion correction parameter when the viewpoint position is the lower end and the center of the left and right of the display image, and the viewpoint position is the lower end and the right end of the display image A ninth storage unit for storing distortion correction parameters;
The display control means acquires any one of the first to ninth distortion correction parameters based on the viewpoint position, or interpolates between a plurality of the first to ninth distortion correction parameters. Then, the interpolation distortion correction parameter is calculated, and the distortion of the display image when projected onto the projection member is corrected based on any of the first to ninth distortion correction parameters or the interpolation distortion correction parameter. It is characterized by doing.

In order to solve the above problems, a display method of a display device of the present invention includes a display unit that displays a display image;
Display control means for displaying the display image on the display means;
A position detection means capable of detecting a viewer's viewpoint position, and a display device display method for projecting the display image onto a projection target member,
A first distortion correction parameter when the viewpoint position is at the upper end and the left end of the viewable range of the display image, and a second when the viewpoint position is at the upper end and the left and right center of the viewable range of the display image A distortion correction parameter, a third distortion correction parameter when the viewpoint position is the upper end and the right end of the viewable range of the display image, and the viewpoint position is the upper and lower center and the left end of the viewable range of the display image. The fourth distortion correction parameter in the case, the fifth distortion correction parameter in the case where the viewpoint position is the vertical center and the horizontal center of the display image viewable range, and the viewpoint position is the viewable range of the display image. And a seventh distortion correction parameter when the viewpoint position is the lower end and the left end of the viewable range of the display image. A meter, an eighth distortion correction parameter when the viewpoint position is the lower end and the center of the left and right of the display image, and the viewpoint position is the lower end and the right end of the display image A ninth storage unit for storing distortion correction parameters;
The display control means acquires any one of the first to ninth distortion correction parameters based on the viewpoint position, or interpolates between a plurality of the first to ninth distortion correction parameters. Then, the interpolation distortion correction parameter is calculated, and the distortion of the display image when projected onto the projection member is corrected based on any of the first to ninth distortion correction parameters or the interpolation distortion correction parameter. It is characterized by doing.

  The present invention can achieve the intended purpose, improve the visibility by correcting the distortion of the display image even when the viewpoint position of the observer moves left and right, and increase the cost of parts. It becomes possible to suppress.

It is the schematic of the head-up display apparatus of 1st embodiment of this invention. It is a block diagram which shows the electric constitution of a control part same as the above. It is a flowchart figure which shows the control method in the same as the above. It is a figure explaining the viewpoint detection in the same as the above. It is a flowchart figure which shows the image correction method in the same as the above. It is a figure which shows the relationship between the viewpoint angle and distortion correction parameter in the same as the above. It is a figure which shows an example of the distortion correction parameter in the same as the above. It is a figure which shows an example of the triangular patch in the same as the above. It is a figure which shows an example of the display image F before correction | amendment in the same as the above, and the display image F after correction | amendment. It is a flowchart figure which shows the image correction method in the head-up display apparatus of 2nd embodiment of this invention. It is a figure which shows the relationship between the viewpoint angle and distortion correction parameter in the same as the above. It is a figure which shows an example of the distortion correction parameter in the same as the above.

Hereinafter, a first embodiment in which the present invention is applied to a head-up display (HUD) device 100 will be described with reference to the accompanying drawings.
The HUD device 100 is installed in a dashboard in a vehicle interior of a vehicle, and as shown in FIG. 1, an imaging unit (position detection unit) 10, a control unit 20, a display unit 30, and a concave mirror 40. And comprising. The display light L indicating the predetermined display image F output from the HUD device 100 is reflected by the windshield 101 of the vehicle and reaches the eyes of the driver (observer) 102. The driver 102 visually recognizes the virtual image V of the display image F displayed in front of the windshield 101.

  The imaging unit 10 includes a known imaging device such as a CCD and peripheral circuits and lenses that control the imaging device. The imaging unit 10 is installed in front of the driver 102 and images the face of the driver 102 and outputs a captured image. .

  The control unit 20 is a so-called microcomputer. The control unit 20 is connected to the imaging unit 10 and the display unit 30, performs a viewpoint position detection process for analyzing the face image of the driver 102 output from the imaging unit 10 and calculating the viewpoint position of the driver 102. Based on the calculation result, a control signal is output to the display means 30 to perform image display control. That is, the control unit 20 functions as the position detection unit of the present invention together with the imaging unit 10 and also functions as the display control unit of the present invention. The control unit 20 generates a predetermined display image and causes the display unit 30 to display the display image.

  The display means 30 includes, for example, a backlight light source 31 and a dot matrix type liquid crystal display panel 32, and emits the display image F as display light L toward the concave mirror 40. The display means 30 may be anything that emits the display image F as display light L, and may be a self-luminous display panel such as an organic EL panel.

  The concave mirror 40 irradiates the windshield 101 with the display light L so that the display light L is focused on the left and right eyes of the driver 102. The concave mirror 40 includes a rotation shaft (not shown). The rotation axis is perpendicular to the drawing of FIG. 1, and the angle of the concave mirror 40 with respect to the windshield 101 can be changed around the rotation axis. Further, the concave mirror 40 is provided with a motor (not shown) as a driving means for changing the angle of the concave mirror 40, and the angle of the concave mirror 40 with respect to the windshield 101 is changed by this motor, and the angle is changed. Can be maintained. As described above, the display light L can be adjusted to the driver's 102 line of sight.

  FIG. 2 shows an electrical configuration of the control unit 20. As shown in FIG. 2, the control unit 20 includes a CPU 21, a ROM 22, a general-purpose memory 23, a video memory 24, and an external device I / F 25.

  The CPU 21 reads out and executes a predetermined program stored in advance in the ROM 22, temporarily stores the captured image from the imaging unit 10, a processed image obtained by performing image processing on the image, a calculation result such as a viewpoint position, and the like in the general-purpose memory 23. Further, the display image F to be displayed on the display means 30 is stored in the video memory 24 using a circuit that performs image processing for creating the display image F.

  The ROM 22 stores a program for operating the CPU 21, distortion correction parameters described later, and the like.

  The general-purpose memory 23 temporarily stores a captured image from the imaging unit 10, a processed image obtained by performing image processing on the captured image, a calculation result such as a viewpoint position, and the like.

  The video memory 24 stores a display image F to be displayed on the display means 30.

  The external device I / F 25 electrically connects the control unit 20 to a vehicle control system unit 103 including a computer that controls the imaging unit 10, the display unit 30, and the vehicle. The external device I / F 25 acquires a captured image from the imaging unit 10, outputs a control signal to the display unit 30, and acquires vehicle information such as a vehicle speed from the vehicle control system unit 103. CPU21 can display vehicle information on the display means 30 based on the acquired vehicle information.

  Next, viewpoint detection processing and image display control in the control unit 20 will be described with reference to FIG.

  First, in step S <b> 1, the CPU 21 detects the left eye and the right eye of the driver 102 from the captured image obtained by capturing the face of the driver 102 output from the imaging unit 10. Specifically, as shown in FIG. 4, for example, template matching which is a well-known image processing technique is performed on the captured image P including the face of the driver 102, and a predetermined template T is moved on the captured image P. Then, the location that matches the template T is detected as the left eye and the right eye of the driver 102 on the captured image P.

  Next, in step S2, the CPU 21 determines the left eye viewpoint position and the right eye viewpoint position in the space of the driver 102 based on the positions of the left eye and the right eye of the driver 102 on the captured image P detected in step S1. And calculate. The position information of the left eye viewpoint position and the right eye viewpoint position may be two-dimensional information or three-dimensional information.

  Next, in step S3, the CPU 21 corrects the distortion of the display image F so as to correspond to the left eye viewpoint position and right eye viewpoint position of the driver 102 calculated in step S2, and generates the display image F. The distortion correction method for the display image F will be described in detail later.

  Next, in step S4, the CPU 21 displays the display image F on the display unit 30, projects the display light L onto the windshield 101, and causes the driver 102 to visually recognize the virtual image V.

  The CPU 21 executes steps S1 to S4 in an infinite loop until the power is turned off.

  Next, an example of a distortion correction method for the display image F will be described with reference to FIG.

  First, in step S11, the CPU 21 calculates a horizontal viewpoint angle θx from the left eye viewpoint position and right eye viewpoint position calculated in step S2. Specifically, with reference to the perpendicular line from the focal plane of the virtual image V, the horizontal position formed by the center of the viewpoint position (the center between the left eye viewpoint position and the right eye viewpoint position) and the perpendicular line from the focal plane of the virtual image V The angle is calculated as the viewpoint angle θx. In this embodiment, the viewpoint angle θx is 0 ° (θx = 0 °) when the center of the viewpoint position is the center of the visible range of the virtual image V (design reference position), and the center of the viewpoint position is the virtual image V. When it is located on the left side as viewed from the driver 102 from the center of the visible range, a negative value (θx = −a °) is obtained, and the center of the viewpoint position is viewed from the center of the visible range of the virtual image V from the driver 102. If it is located on the right side, a positive value (θx = a °) is assumed (a is a positive number).

  Next, in step S12, the CPU 21 acquires a distortion correction parameter corresponding to the viewpoint angle calculated in step S11. For example, as shown in FIG. 6, a plurality of distortion correction parameters are set according to three viewpoint angles, and are stored in the ROM 22. That is, the first distortion correction parameter RP1 corresponding to the viewpoint angle θx (θx = −60 °) when the center of the viewpoint position is the left end of the visible range of the display image F (virtual image V), and the center of the viewpoint position Is the center of the viewable range of the display image F, the second distortion correction parameter RP2 corresponding to the viewpoint angle θx (θx = 0 °), and the center of the viewpoint position is the left end of the viewable range of the display image F A third distortion correction parameter RP3 corresponding to a certain viewpoint angle θx (θx = −60 °) is stored in the ROM 22. Note that the viewpoint angle θx in the case where the center of the viewpoint position is the left and right ends of the visible range of the display image F is not limited to the present embodiment and is arbitrarily determined. As shown in FIG. 7, each of the first to third distortion correction parameters RP1 to RP3 has an x-axis (horizontal axis) on the display surface of the display means 30 of a plurality of vertices of a triangular patch used in texture mapping described later. ) Direction position and y-axis (vertical axis) direction position (number of dots from the origin). FIG. 7 shows an example in which values in the x-axis direction and values in the y-axis direction of 25 vertices 1 to 25 are set in the first to third distortion correction parameters RP1 to RP3. The number of is arbitrary. In the first to third distortion correction parameters RP1 to RP3, the position in the x-axis direction and the position in the y-axis direction of the apex of the triangular patch are determined from the viewpoint angle θx corresponding to the display image F projected on the windshield 101. It is set so that distortion occurs in the opposite direction to the distortion that occurs when viewed.

The first to third distortion correction parameters RP1 to RP3 are stored in the ROM 22 as a lookup table, and the CPU 21 reads the first to third distortion correction parameters RP1 from the ROM 22 as follows based on the calculated viewpoint angle θx. Read ~ RP3. First, when the viewpoint angle θx is any one of −60 °, 0 °, and 60 °, the CPU 21 stores one of the first to third distortion correction parameters RP1 to RP3 corresponding to the viewpoint angle θx in the ROM 22. Read from. When the viewpoint angle θx is a value that does not correspond to the first to third distortion correction parameters RP1 to RP3 (for example, when the viewpoint angle θx = −30 ° or when the viewpoint angle θx = 30 °), The CPU 21 acquires two distortion correction parameters corresponding to the viewpoint angles θx before and after the first to third distortion correction parameters RP1 to RP3, performs an interpolation process between them, and calculates the calculated viewpoint angle An interpolation distortion correction parameter RP ′ corresponding to θx is acquired. That is, when the center of the viewpoint position is located between the center and the left end of the visible range of the display image F (when the viewpoint angle θx is negative (θx = −a °)), the CPU 21 performs the first and second operations. Interpolation processing between the second distortion correction parameters RP1 and RP2 is performed to calculate the interpolation distortion correction parameter RP ′, and the center of the viewpoint position is located between the center and the right end of the visible range of the display image F (viewpoint When the angle θx is positive (when θx = a °), the CPU 21 performs interpolation processing between the second and third distortion correction parameters RP2 and RP3 to calculate an interpolation distortion correction parameter RP ′. As an example of the interpolation processing, when the midpoint between the distortion correction parameter RPn and the distortion correction parameter RPn + 1 is acquired as the interpolation distortion correction parameter RP ′, the value xm in the x-axis direction of the m-th vertex of the interpolation distortion correction parameter RP ′ The value ym in the y-axis direction is obtained by the following (Formula 1).
(Formula 1)
xm = (xnm−x (n + 1) m) / 2
ym = (ynm−y (n + 1) m) / (xnm−x (n + 1) m) × xm + ynm
Note that xnm and ynm respectively indicate the value in the x-axis direction and the value in the y-axis direction of the m-th apex in the distortion correction parameter RPn, and x (n + 1) m and y (n + 1) m respectively indicate the distortion correction parameter RPn + 1. The value in the x-axis direction and the value in the y-axis direction of the m-th apex in FIG.
In addition to linear interpolation, there are three types of polynomials used as an interpolation function, such as cubic interpolation, Lagrangian interpolation, and spline interpolation. Any of them may be used for interpolation processing. In addition, a high-order polynomial is used for the interpolation function used for interpolation processing for vertices located at locations with high distortion, and a low-order polynomial is used for the interpolation function used for interpolation processing for vertices located at locations with low distortion. The polynomial may be changed for each corresponding point. Although higher-order polynomials require more computation, distortion correction accuracy is improved. On the other hand, low-order polynomials have a low distortion correction accuracy but a small amount of calculation. By properly using the two according to the corresponding points, both the distortion correction accuracy and the calculation speed can be improved.

  Next, in step S13, the CPU 21 corrects the distortion of the display image F based on the first to third distortion correction parameters RP1 to RP3 or the interpolation distortion correction parameter RP 'acquired in step S12. Specifically, first, as shown in FIG. 8, the CPU 21 is based on the x-axis direction value and the y-axis direction value of each vertex acquired as the distortion correction parameters RP1 to RP3 or the interpolation distortion correction parameter RP ′. To create a triangular patch. Next, as shown in FIG. 9A, the CPU 21 divides the display image F into substantially triangular textures F <b> 1 to F <b> 32 as many as the number of triangular patches (32 in the present embodiment). As shown in (b), these textures F1 to F32 are pasted on the corresponding triangular patches by texture mapping. The texture mapping may use a function implemented in a circuit that performs image processing of the CPU 21 or may be a function implemented as software. The corrected display image F obtained by the texture mapping is given a distortion in a direction opposite to that generated when the display image F projected on the windshield 101 is viewed from the calculated viewpoint angle θx. When the display image F is displayed on the display means 30, the display image F without distortion is obtained when projected by the windshield 101.

  CPU21 performs the correction | amendment of the display image F by performing step S11-S13.

The HUD device 100 according to the present embodiment includes a display unit 30 that displays a display image F, a control unit 20 that displays the display image F on the display unit 30, and a position detection unit that can detect the viewpoint position of the driver 102 (imaging). Unit 10 and control unit 20), and projecting the display image F onto the windshield 101,
A first distortion correction parameter RP1 when the viewpoint position is the left end of the visible range of the display image F, and a second distortion correction parameter RP2 when the viewpoint position is the center of the visible range of the display image F. And a ROM 22 that stores a third distortion correction parameter RP3 when the viewpoint position is the right end of the visible range of the display image F,
The control unit 20 acquires any one of the first to third distortion correction parameters RP1 to RP3 based on the viewpoint position, or between two of the first to third distortion correction parameters RP1 to RP3. Is interpolated to calculate an interpolation distortion correction parameter RP ′ and is projected onto the windshield 101 based on one of the first to third distortion correction parameters RP1 to RP3 or the interpolation distortion correction parameter RP ′. The distortion of the display image F is corrected.

  Further, the display method of the HUD device 100 acquires any one of the first to third distortion correction parameters RP1 to RP3 based on the viewpoint position, or the first to third distortion correction parameters RP1 to RP3. The interpolation distortion correction parameter RP ′ is calculated by interpolating between the two, and the windshield 101 is determined based on one of the first to third distortion correction parameters RP1 to RP3 or the interpolation distortion correction parameter RP ′. The distortion of the display image F when projected is corrected.

  According to this, even when the viewpoint position of the driver 102 moves to the left and right, the distortion of the display image can be corrected to improve the visibility, and three distortion correction parameters stored in the ROM 22 can be stored. It is possible to suppress the increase in component cost.

  Further, in the HUD device 100 according to the present embodiment, the control unit 20 causes the first and second distortion correction parameters when the viewpoint position is located between the center and the left end of the visible range of the display image F. Interpolation processing between RP1 and RP2 is performed to calculate an interpolation distortion correction parameter RP ′. When the viewpoint position is located between the center and the right end of the visible range of the display image F, the second and third The distortion correction parameters RP2 and RP3 are interpolated to calculate an interpolation distortion correction parameter RP ′.

  Further, the display method of the HUD device 100 is such that when the viewpoint position is located between the center and the left end of the visible range of the display image F, the first and second distortion correction parameters RP1 and RP2 are set. Interpolation processing is performed to calculate the interpolation distortion correction parameter RP ′, and when the viewpoint position is located between the center and the right end of the visible range of the display image F, the second and third distortion correction parameters RP2, The interpolation distortion correction parameter RP ′ is calculated by performing interpolation processing between RP3.

  According to this, even when the viewpoint position of the driver 102 moves between the center and the left and right ends of the visible range of the display image F, it is possible to perform highly accurate distortion correction.

  Next, a second embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected to the part which is the same as that of the above-mentioned embodiment, or the detailed description is abbreviate | omitted.

  The second embodiment is different from the above-described embodiment in a distortion correction parameter stored in the ROM 22 as a storage unit and a distortion correction method using the distortion correction parameter. Hereinafter, an example of the distortion correction method for the display image F in the present embodiment will be described with reference to FIG.

  First, in step S21, the CPU 21 calculates a horizontal viewpoint angle θx from the left eye viewpoint position and right eye viewpoint position calculated in step S2. Specifically, with reference to the perpendicular line from the focal plane of the virtual image V, the horizontal position formed by the center of the viewpoint position (the center between the left eye viewpoint position and the right eye viewpoint position) and the perpendicular line from the focal plane of the virtual image V The angle is calculated as the viewpoint angle θx. In the present embodiment, the horizontal viewpoint angle θx is 0 ° (θx = 0 °) when the center of the viewpoint position is the center of the visible range of the virtual image V (design reference position), and the center of the viewpoint position is When it is located on the left side when viewed from the driver 102 from the center of the visible range of the virtual image V, the value is negative (θx = −a °), and the center of the viewpoint position is from the center of the visible range of the virtual image V. When it is located on the right side when viewed from 102, it is assumed that the value is positive (θx = a °) (a is a positive number). Similarly, the CPU 21 calculates the vertical viewing angle θy. Specifically, with the vertical line from the focal plane of the virtual image V as a reference, the vertical position formed by the center of the viewpoint position (the center between the left eye viewpoint position and the right eye viewpoint position) and the vertical line from the focal plane of the virtual image V The angle is calculated as the viewpoint angle θy. In this embodiment, the viewpoint angle θy in the vertical direction is 0 ° (θy = 0 °) when the center of the viewpoint position is the center of the visible range of the virtual image V (design reference position), and the center of the viewpoint position is When it is located below the center of the visible range of the virtual image V when viewed from the driver 102, the value is negative (θy = −b °), and the center of the viewpoint position is driven from the center of the visible range of the virtual image V. When it is located on the upper side when viewed from the person 102, it is assumed that the value is positive (θy = b °) (b is a positive number).

  Next, in step S22, the CPU 21 acquires distortion correction parameters corresponding to the viewpoint angles θx and θy calculated in step S21. For example, as shown in FIG. 11, a plurality of distortion correction parameters are set according to combinations of three viewpoint angles θx and θy, and are stored in the ROM 22. That is, a combination of the viewpoint angle θx (θx = −60 °) and the viewpoint angle θy (θy = 60 °) when the center of the viewpoint position is the upper end and the left end of the visible range of the display image F (virtual image V). The corresponding first distortion correction parameter RP1, the viewpoint angle θx (θx = 0 °) and the viewpoint angle θy (when the center of the viewpoint position is the upper end and the left and right center of the visible range of the display image F (virtual image V)). The second distortion correction parameter RP2 corresponding to the combination with θy = 60 °) and the viewpoint angle θx (θx = θx = θx = θx = θx = θx = θx = θx) when the center of the viewpoint position is the upper end and the right end of the viewable range of the display image F 60 °) and the third distortion correction parameter RP3 corresponding to the combination of the viewpoint angle θy (θy = 60 °) and the center of the viewpoint position at the upper and lower centers and the left end of the visible range of the display image F (virtual image V). View angle when there is Fourth distortion correction parameter RP4 corresponding to a combination of x (θx = −60 °) and viewpoint angle θy (θy = 0 °), and the center of the viewpoint position above and below the visible range of display image F (virtual image V) The fifth distortion correction parameter RP5 corresponding to the combination of the viewpoint angle θx (θx = 0 °) and the viewpoint angle θy (θy = 0 °) in the case of the center and the left-right center, and the center of the viewpoint position is the display image F A sixth distortion correction parameter RP6 corresponding to the combination of the viewpoint angle θx (θx = 60 °) and the viewpoint angle θy (θy = 0 °) in the upper and lower center and the right end of the visible range of (virtual image V); The combination of the viewpoint angle θx (θx = −60 °) and the viewpoint angle θy (θy = −60 °) when the center of the viewpoint position is the lower end and the left end of the visible range of the display image F (virtual image V). Corresponding seventh distortion correction parameter P7 and the viewpoint angle θx (θx = 0 °) and the viewpoint angle θy (θy = −60 °) when the center of the viewpoint position is the lower end and the center of the left and right of the visible range of the display image F (virtual image V). An eighth distortion correction parameter RP8 corresponding to the combination, a viewpoint angle θx (θx = 60 °) and a viewpoint angle θy when the center of the viewpoint position is the lower end and the right end of the visible range of the display image F (virtual image V). The ninth distortion correction parameter RP9 corresponding to the combination with (θy = −60 °) is stored in the ROM 22. Note that the viewpoint angle θx when the center of the viewpoint position is the left and right ends of the visible range of the display image F and the viewpoint angle θy when the center of the viewpoint position is the upper and lower ends of the visible range of the display image F are: It is not limited to this embodiment, and is arbitrarily determined. As shown in FIG. 12, each of the first to ninth distortion correction parameters RP1 to RP9 has an x-axis (horizontal axis) on the display surface of the display means 30 of a plurality of vertices of a triangular patch used in texture mapping described later. ) Direction position and y-axis (vertical axis) direction position (number of dots from the origin). FIG. 12 shows an example in which the values in the x-axis direction and the value in the y-axis direction of the 25 vertices of No. 1 to No. 25 are set in the first to ninth distortion correction parameters RP1 to RP9. The number of vertices is arbitrary. In the first to ninth distortion correction parameters RP1 to RP9, the positions of the apexes of the triangular patches in the x-axis direction and the y-axis direction correspond to the viewpoint angle θx corresponding to the display image F projected on the windshield 101, respectively. The distortion is set so as to generate a distortion in a direction opposite to that generated when viewed from θy.

The first to ninth distortion correction parameters RP1 to RP9 are stored in the ROM 22 as a look-up table, and the CPU 21 reads the first to ninth distortion corrections from the ROM 22 based on the calculated viewpoint angles θx and θy as follows. Read parameters RP1 to RP9. First, when the viewpoint angle θx is any one of −60 °, 0 °, and 60 ° and the viewpoint angle θy is any one of −60 °, 0 °, and 60 °, the CPU 21 Any one of the first to ninth distortion correction parameters RP1 to RP9 corresponding to the combination of θx and θy is read from the ROM 22.
The viewpoint angle θx is a value that does not correspond to the first to ninth distortion correction parameters RP1 to RP9 (for example, the viewpoint angle θx = −30 °), and the viewpoint angle θy is −60 °, 0 °, and 60 °. In any case, the CPU 21 corresponds to a combination of the viewpoint angle θx before and after the calculated viewpoint angle θx and the calculated viewpoint angle θy among the first to ninth distortion correction parameters RP1 to RP9. Two distortion correction parameters are acquired and interpolation processing is performed between them, and an interpolation distortion correction parameter RP ′ corresponding to the calculated combination of viewpoint angles θx and θy is acquired. That is, when the center of the viewpoint position is located between the left and right center and the left end of the visible range of the display image F (when the viewpoint angle θx is negative (θx = −a °)), the CPU 21 Between the second distortion correction parameters RP1 and RP2 (when the viewpoint angle θy = 60 °), between the fourth and fifth distortion correction parameters RP4 and RP5 (when the viewpoint angle θy = 0 °), or One of the seventh and eighth distortion correction parameters RP7 and RP8 (when the viewpoint angle θy = −60 °) is interpolated to calculate an interpolation distortion correction parameter RP ′. When the center of the viewpoint position is located between the right and left center and the right end of the visible range of the display image F (when the viewpoint angle θx is plus (θx = a °)), the CPU 21 Between the third distortion correction parameters RP2 and RP3 (when the viewing angle θy = 60 °), between the fifth and sixth distortion correction parameters RP5 and RP6 (when the viewing angle θy = 0 °), or The interpolation distortion correction parameter RP ′ is calculated by performing interpolation processing between any of the eighth and ninth distortion correction parameters RP8 and RP9 (when the viewpoint angle θy = −60 °).

  Further, the viewpoint angle θx is any of −60 °, 0 °, and 60 °, and the viewpoint angle θy is a value that does not correspond to the first to ninth distortion correction parameters RP1 to RP9 (for example, the viewpoint angle θy). = 30 °), the CPU 21 corresponds to a combination of the calculated viewpoint angle θx of the first to ninth distortion correction parameters RP1 to RP9 and the viewpoint angle θy before and after the calculated viewpoint angle θy. Two distortion correction parameters are acquired and interpolation processing is performed between them, and an interpolation distortion correction parameter RP ′ corresponding to the calculated combination of viewpoint angles θx and θy is acquired. That is, when the center of the viewpoint position is located between the upper end of the viewable range of the display image F and the upper and lower centers (when the viewpoint angle θy is positive (θb = b °)), the CPU 21 Between the fourth distortion correction parameters RP1 and RP4 (when the viewpoint angle θx = −60 °), between the second and fifth distortion correction parameters RP2 and RP5 (when the viewpoint angle θx = 0 °), or One of the third and sixth distortion correction parameters RP3 and RP6 (when the viewpoint angle θx = 60 °) is interpolated to calculate an interpolation distortion correction parameter RP ′. When the center of the viewpoint position is located between the upper and lower centers and the lower end of the viewable range of the display image F (when the viewpoint angle θy is negative (θy = −b °)), the CPU 21 Between the seventh distortion correction parameters RP4 and RP7 (when the viewpoint angle θx = −60 °), between the fifth and eighth distortion correction parameters RP5 and RP8 (when the viewpoint angle θx = 0 °), Alternatively, the interpolation distortion correction parameter RP ′ is calculated by performing interpolation processing between any of the sixth and ninth distortion correction parameters RP6 and RP9 (when the viewpoint angle θx = 60 °).

  When the viewpoint angles θx and θy are values that do not correspond to the first to ninth distortion correction parameters RP1 to RP9 (for example, when the viewpoint angles θx = −30 ° and θy = 30 °, In the case of θx = 30 ° and θy = −30 °), the CPU 21 has four distortions corresponding to combinations of the viewpoint angles θx and θy before and after the first to ninth distortion correction parameters RP1 to RP9. A correction parameter is acquired and an interpolation process is performed between them, and an interpolation distortion correction parameter RP ′ corresponding to the calculated viewpoint angles θx and θy is acquired. That is, the center of the viewpoint position is located between the upper end, the left end, the upper end, the left and right center, the top and bottom center, and the left end, the top and bottom center, and the left and right center of the display image F (view angle θx is negative (θx = −a °) and the viewpoint angle θy is positive (θy = b °), the CPU 21 interpolates between the first, second, fourth and fifth distortion correction parameters RP1, RP2, RP4 and RP5. The interpolation distortion correction parameter RP ′ is calculated by processing. Further, when the center of the viewpoint position is located between the upper end, the left and right center and the upper end, the right end and the upper and lower center, and the left and right center and the upper and lower center and the right end of the viewable range of the display image F (view angle θx is positive (θx = a °) and when the viewpoint angle θy is positive (θy = b °), the CPU 21 interpolates between the second, third, fifth and sixth distortion correction parameters RP2, RP3, RP5 and RP6. Then, the interpolation distortion correction parameter RP ′ is calculated. Further, when the center of the viewpoint position is located between the upper and lower center, the left end and the upper and lower center, the left and right center and the lower end, and the left end and the lower end and the left and right center of the visible range of the display image F (the viewpoint angle θx is negative (θx = −a °) and the viewpoint angle θy is negative (θy = −b °)), the CPU 21 is between the fourth, fifth, seventh, and eighth distortion correction parameters RP4, RP5, RP7, and RP8. Interpolation processing is performed to calculate an interpolation distortion correction parameter RP ′. Further, when the center of the viewpoint position is located between the vertical center, the horizontal center, the vertical center, the right edge and the bottom edge, and the horizontal center, the bottom edge, and the right edge of the viewable range of the display image F (the viewpoint angle θx is positive (θx = a °) and when the viewpoint angle θy is negative (θy = −b °), the CPU 21 interpolates between the fifth, sixth, eighth, and ninth distortion correction parameters RP5, RP6, RP8, and RP9. The interpolation distortion correction parameter RP ′ is calculated by processing.

なお、θｎｘとθｎｙはそれぞれ歪み補正パラメータＲＰｎに対応する視点角度θｘの値及び視点角度θｙの値を示す。同様にθ（ｎ＋１）ｘとθ（ｎ＋１）ｙはそれぞれ歪み補正パラメータＲＰ（ｎ＋１）に対応する視点角度θｘの値及び視点角度θｙの値を示す。同様にθ（ｎ＋３）ｘとθ（ｎ＋３）ｙはそれぞれ歪み補正パラメータＲＰ（ｎ＋３）に対応する視点角度θｘの値及び視点角度θｙの値を示す。同様にθ（ｎ＋４）ｘとθ（ｎ＋４）ｙはそれぞれ歪み補正パラメータＲＰ（ｎ＋４）に対応する視点角度θｘの値及び視点角度θｙの値を示す。また、ｓｕｍＬはそれぞれの距離Ｌｎ，Ｌ（ｎ＋１），Ｌ（ｎ＋３），Ｌ（ｎ＋４）の合計を示す。
次に、ＣＰＵ２１は、各歪み補正パラメータＲＰｎ，ＲＰ（ｎ＋１），ＲＰ（ｎ＋３），ＲＰ（ｎ＋４）に対する重みＷｎ，Ｗ（ｎ＋１），Ｗ（ｎ＋３），Ｗ（ｎ＋４）を下記式３を用いて算出する。なお、算出された視点位置が近い程、重みの値が大きくなるようにする。
（式３）
Ｗｎ＝（Ｌ（ｎ＋１）＋Ｌ（ｎ＋３）＋Ｌ（ｎ＋４））／ｓｕｍＬ
Ｗ（ｎ＋１）＝（Ｌｎ＋Ｌ（ｎ＋３）＋Ｌ（ｎ＋４））／ｓｕｍＬ
Ｗ（ｎ＋３）＝（Ｌｎ＋Ｌ（ｎ＋１）＋Ｌ（ｎ＋４））／ｓｕｍＬ
Ｗ（ｎ＋４）＝（Ｌｎ＋Ｌ（ｎ＋１）＋Ｌ（ｎ＋３））／ｓｕｍＬ
次に、ＣＰＵ２１は、各重みＷｎ，Ｗ（ｎ＋１），Ｗ（ｎ＋３），Ｗ（ｎ＋４）を各歪み補正パラメータＲＰｎ，ＲＰ（ｎ＋１），ＲＰ（ｎ＋３），ＲＰ（ｎ＋４）に掛けて足し合わせることで（下記式４参照）、補間歪み補正パラメータＲＰ’を算出する。
（式４）
ＲＰ’＝ＲＰｎ×Ｗｎ＋ＲＰ（ｎ＋１）×Ｗ（ｎ＋１）＋ＲＰ（ｎ＋３）×Ｗ（ｎ＋３）＋ＲＰ（ｎ＋４）×Ｗ（ｎ＋４）
このとき、補間歪み補正パラメータＲＰ’のｍ番の頂点のｘ軸方向の値ｘｍとｙ軸方向の値ｙｍとは以下の式５で求められる。
（式５）
ｘｍ＝ｘｎｍ×Ｗｎ＋ｘ（ｎ＋１）ｍ×Ｗ（ｎ＋１）＋ｘ（ｎ＋３）ｍ×Ｗ（ｎ＋３）＋ｘ（ｎ＋４）ｍ×Ｗ（ｎ＋４）
ｙｍ＝ｙｎｍ×Ｗｎ＋ｙ（ｎ＋１）ｍ×Ｗ（ｎ＋１）＋ｙ（ｎ＋３）ｍ×Ｗ（ｎ＋３）＋ｙ（ｎ＋４）ｍ×Ｗ（ｎ＋４）
なお、ｘｎｍとｙｎｍは、それぞれ歪み補正パラメータＲＰｎにおけるｍ番の頂点のｘ軸方向の値とｙ軸方向の値を示す。同様にｘ（ｎ＋１）ｍとｙ（ｎ＋１）ｍは、それぞれ歪み補正パラメータＲＰ（ｎ＋１）におけるｍ番の頂点のｘ軸方向の値とｙ軸方向の値を示す。同様にｘ（ｎ＋３）ｍとｙ（ｎ＋３）ｍは、それぞれ歪み補正パラメータＲＰ（ｎ＋３）におけるｍ番の頂点のｘ軸方向の値とｙ軸方向の値を示す。同様にｘ（ｎ＋４）ｍとｙ（ｎ＋４）ｍは、それぞれ歪み補正パラメータＲＰ（ｎ＋４）におけるｍ番の頂点のｘ軸方向の値とｙ軸方向の値を示す。
また、補間関数として用いる多項式には、代表的なものとして線形補間のほかに、３次補間やラグランジュ補間、スプライン補間などがあるが、いずれを使用して補間処理を行っても良い。また、歪みが大きい個所に位置する頂点について補間処理に使用する補間関数に高次の多項式を用い、歪みが小さい個所に位置する頂点について補間処理に使用する補間関数に低次の多項式を用いるなど、多項式を対応点毎に変更してもよい。高次の多項式は計算量が増えるものの、歪みの補正精度は向上する。一方、低次の多項式は歪みの補正精度は低いが、計算量が少ない。両者を対応点によって使い分けることで、歪みの補正精度と計算速度の向上を両立させることができる。 As an example of the interpolation processing, interpolation processing is performed by interpolating between four distortion correction parameters of the distortion correction parameter RPn, the distortion correction parameter RP (n + 1), the distortion correction parameter RP (n + 3), and the distortion correction parameter RP (n + 4). A case where the correction parameter RP ′ is acquired will be described as an example.
The interpolation distortion correction parameter RP ′ is a distance Ln, L (n + 1), L () between the calculated viewpoint position and the viewpoint position corresponding to each distortion correction parameter RPn, RP (n + 1), RP (n + 3), RP (n + 4). weights Wn, W (n + 1), W (n + 3), W (n + 4) of the distortion correction parameters RPn, RP (n + 1), RP (n + 3), RP (n + 4) are calculated from n + 3) and L (n + 4), The closer to the calculated viewpoint position, the larger the weight can be obtained.
Specifically, first, the CPU 21 calculates the distance between the viewpoint position corresponding to each distortion correction parameter RPn, RP (n + 1), RP (n + 3), RP (n + 4) and the calculated viewpoint position to Ln, L (n + 1). ), L (n + 3), and L (n + 4) are obtained using the following equation 2.

Note that θnx and θny indicate the value of the viewpoint angle θx and the value of the viewpoint angle θy corresponding to the distortion correction parameter RPn, respectively. Similarly, θ (n + 1) x and θ (n + 1) y indicate the value of the viewpoint angle θx and the value of the viewpoint angle θy corresponding to the distortion correction parameter RP (n + 1), respectively. Similarly, θ (n + 3) x and θ (n + 3) y indicate the value of the viewpoint angle θx and the value of the viewpoint angle θy corresponding to the distortion correction parameter RP (n + 3), respectively. Similarly, θ (n + 4) x and θ (n + 4) y indicate the values of the viewpoint angle θx and the viewpoint angle θy corresponding to the distortion correction parameter RP (n + 4), respectively. Also, sumL represents the sum of the distances Ln, L (n + 1), L (n + 3), and L (n + 4).
Next, the CPU 21 uses weights Wn, W (n + 1), W (n + 3), and W (n + 4) for the distortion correction parameters RPn, RP (n + 1), RP (n + 3), and RP (n + 4) using the following formula 3. To calculate. Note that the closer the calculated viewpoint position is, the larger the weight value is.
(Formula 3)
Wn = (L (n + 1) + L (n + 3) + L (n + 4)) / sumL
W (n + 1) = (Ln + L (n + 3) + L (n + 4)) / sumL
W (n + 3) = (Ln + L (n + 1) + L (n + 4)) / sumL
W (n + 4) = (Ln + L (n + 1) + L (n + 3)) / sumL
Next, the CPU 21 multiplies the respective weights Wn, W (n + 1), W (n + 3), and W (n + 4) by the respective distortion correction parameters RPn, RP (n + 1), RP (n + 3), and RP (n + 4) and adds them. Thus, the interpolation distortion correction parameter RP ′ is calculated (see Equation 4 below).
(Formula 4)
RP ′ = RPn × Wn + RP (n + 1) × W (n + 1) + RP (n + 3) × W (n + 3) + RP (n + 4) × W (n + 4)
At this time, the value xm in the x-axis direction and the value ym in the y-axis direction of the m-th apex of the interpolation distortion correction parameter RP ′ are obtained by the following Expression 5.
(Formula 5)
xm = xnm * Wn + x (n + 1) m * W (n + 1) + x (n + 3) m * W (n + 3) + x (n + 4) m * W (n + 4)
ym = ynm * Wn + y (n + 1) m * W (n + 1) + y (n + 3) m * W (n + 3) + y (n + 4) m * W (n + 4)
Note that xnm and ynm respectively indicate the value in the x-axis direction and the value in the y-axis direction of the m-th apex in the distortion correction parameter RPn. Similarly, x (n + 1) m and y (n + 1) m indicate the value in the x-axis direction and the value in the y-axis direction of the m-th apex in the distortion correction parameter RP (n + 1), respectively. Similarly, x (n + 3) m and y (n + 3) m indicate the value in the x-axis direction and the value in the y-axis direction of the m-th apex in the distortion correction parameter RP (n + 3), respectively. Similarly, x (n + 4) m and y (n + 4) m indicate the value in the x-axis direction and the value in the y-axis direction of the m-th apex in the distortion correction parameter RP (n + 4), respectively.
In addition to linear interpolation, there are three types of polynomials used as an interpolation function, such as cubic interpolation, Lagrangian interpolation, and spline interpolation. Any of them may be used for interpolation processing. In addition, a high-order polynomial is used for the interpolation function used for interpolation processing for vertices located at locations with high distortion, and a low-order polynomial is used for the interpolation function used for interpolation processing for vertices located at locations with low distortion. The polynomial may be changed for each corresponding point. Although higher-order polynomials require more computation, distortion correction accuracy is improved. On the other hand, low-order polynomials have a low distortion correction accuracy but a small amount of calculation. By properly using the two according to the corresponding points, both the distortion correction accuracy and the calculation speed can be improved.

  In the above example, the interpolation distortion correction parameter RP ′ is calculated by interpolating between the four distortion correction parameters, but two distortion correction parameters (for example, distortion correction parameters RPn, RP (n + 1)) are calculated. Similarly, when the interpolation distortion correction parameter RP ′ is calculated by performing interpolation processing between the distances Ln, L (n + 1) between the calculated viewpoint position and the viewpoint position corresponding to each distortion correction parameter RPn, RP (n + 1). ), The weights Wn and W (n + 1) of the distortion correction parameters RPn and RP (n + 1) are calculated, and the weights can be obtained by increasing the closer to the calculated viewpoint position.

  Next, in step S23, the CPU 21 corrects the distortion of the display image F based on the first to ninth distortion correction parameters RP1 to RP9 or the interpolation distortion correction parameter RP 'acquired in step S22. Specifically, first, as shown in FIG. 8, the CPU 21 is based on the x-axis direction value and the y-axis direction value of each vertex acquired as the distortion correction parameters RP1 to RP9 or the interpolation distortion correction parameter RP ′. To create a triangular patch. Next, as shown in FIG. 9A, the CPU 21 divides the display image F into substantially triangular textures F <b> 1 to F <b> 32 as many as the number of triangular patches (32 in the present embodiment). As shown in (b), these textures F1 to F32 are pasted on the corresponding triangular patches by texture mapping. The texture mapping may use a function implemented in a circuit that performs image processing of the CPU 21 or may be a function implemented as software. The corrected display image F obtained by the texture mapping is given a distortion in a direction opposite to that generated when the display image F projected on the windshield 101 is viewed from the calculated viewpoint angles θx and θy. When the subsequent display image F is displayed on the display means 30, a display image F without distortion is obtained when projected by the windshield 101.

  CPU21 performs the correction | amendment of the display image F by performing step S21-S23.

The HUD device 100 according to the present embodiment includes a display unit 30 that displays a display image F, a control unit 20 that displays the display image F on the display unit 30, and a position detection unit that can detect the viewpoint position of the driver 102 (imaging). Unit 10 and control unit 20), and projecting the display image F onto the windshield 101,
A first distortion correction parameter RP1 when the viewpoint position is at the upper end and the left end of the viewable range of the display image F, and a second when the viewpoint position is at the upper end and the left and right center of the viewable range of the display image F. Distortion correction parameter RP2, a third distortion correction parameter RP3 when the viewpoint position is at the upper end and the right end of the viewable range of the display image F, and the upper and lower center of the viewable range of the display image F. A fourth distortion correction parameter RP4 in the case of the left end, a fifth distortion correction parameter RP5 in the case where the viewpoint position is the vertical center and the horizontal center of the viewable range of the display image F, and the viewpoint position is the display image. The sixth distortion correction parameter RP6 in the case where F is in the upper and lower center and the right end of the visible range, and the viewpoint position is the lower end and the left end of the visible range of the display image F. The seventh distortion correction parameter RP7, the eighth distortion correction parameter RP8 when the viewpoint position is at the lower end and the center of the left and right of the display image F, and the viewpoint position allows the display image F to be viewed. A ROM 22 for storing a ninth distortion correction parameter RP9 for the lower end and the right end of the range;
The control unit 20 acquires any one of the first to ninth distortion correction parameters RP1 to RP9 based on the viewpoint position or a plurality of the first to ninth distortion correction parameters RP1 to RP9. Is interpolated to calculate an interpolation distortion correction parameter RP ′, and is projected onto the windshield 101 based on one of the first to ninth distortion correction parameters RP1 to RP9 or the interpolation distortion correction parameter RP ′. The distortion of the display image F is corrected.

  Also, the display method of the HUD device 100 acquires any one of the first to ninth distortion correction parameters RP1 to RP9 based on the viewpoint position, or the first to ninth distortion correction parameters RP1 to RP9. Are interpolated to calculate an interpolation distortion correction parameter RP ′, and the windshield 101 is calculated based on one of the first to ninth distortion correction parameters RP1 to RP9 or the interpolation distortion correction parameter RP ′. The distortion of the display image F when projected is corrected.

  According to this, even when the viewpoint position of the driver 102 moves up, down, left, and right, the distortion of the display image can be corrected to improve the visibility, and the distortion correction parameter stored in the ROM 22 can be set to 9. Therefore, it is possible to suppress the increase in component cost.

  Further, in the HUD device 100 according to the present embodiment, the control unit 20 has the viewpoint position between the upper end, the left end, the upper end, the left / right center, the upper / lower center, the left end, the upper / lower center, and the left / right center of the display image F visible range. Is interpolated between the first, second, fourth, and fifth distortion correction parameters RP1, RP2, RP4, and RP5 to calculate an interpolation distortion correction parameter RP ′, and the viewpoint position is The fourth, fifth, seventh, and eighth distortions when the display image F is located between the upper and lower center, the left and upper ends, the upper and lower centers, the left and right centers and the lower ends, and the left end and the lower ends and the left and right centers of the display image F. Interpolation processing is performed between the correction parameters RP4, RP5, RP7, and RP8 to calculate an interpolation distortion correction parameter RP ′, and the viewpoint position is the upper end, the left and right center, the upper end, the right end, and the upper and lower center of the display image F. If it is located between the left and right center, the top and bottom center, and the right end, interpolation processing is performed by interpolating between the second, third, fifth, and sixth distortion correction parameters RP2, RP3, RP5, and RP6. When the parameter RP ′ is calculated and the viewpoint position is located between the upper and lower center, the left and right center, the upper and lower center, the right end and the lower end, the left and right center, the lower end, and the right end of the visible range of the display image F, the fifth , Sixth, eighth, and ninth distortion correction parameters RP5, RP6, RP8, and RP9 are interpolated to calculate an interpolation distortion correction parameter RP ′.

  The display method of the HUD device 100 is such that the viewpoint position is located between the upper end, left end, upper end, left / right center, upper / lower center, left end, upper / lower center, and left / right center of the viewable range of the display image F. , First, second, fourth, and fifth distortion correction parameters RP1, RP2, RP4, and RP5 are interpolated to calculate an interpolation distortion correction parameter RP ′, and the viewpoint position is visible in the display image F. The fourth, fifth, seventh, and eighth distortion correction parameters RP4, RP5, RP5, RP5, RP5, RP5, RP5, RP5, RP5, RP5, RP5, RP5, RP5 Interpolation processing between RP7 and RP8 is performed to calculate an interpolation distortion correction parameter RP ', and the viewpoint position is at the upper end, the left and right center and the upper end, the right end and the upper and lower center, and the left and right center and the upper and lower center of the display image F. If it is located between the right end and the second, third, fifth and sixth distortion correction parameters RP2, RP3, RP5 and RP6, interpolation processing is performed to calculate an interpolation distortion correction parameter RP '. When the viewpoint position is located between the vertical center, the horizontal center, the vertical center, the right edge and the bottom edge, and the horizontal center, the bottom edge, and the right edge of the viewable range of the display image F, the fifth, sixth, eighth , Ninth interpolation correction parameters RP5, RP6, RP8, RP9 are interpolated to calculate an interpolation distortion correction parameter RP ′.

  According to this, even when the viewpoint position of the driver 102 moves between the center of the viewable range of the display image F and the upper and lower ends and the left and right ends, it is possible to perform highly accurate distortion correction. .

  Note that the present invention is not limited to the above-described embodiment, and various modifications (including deletion of constituent elements) can be made without departing from the scope of the invention. In the present embodiment, the HUD device 100 is exemplified as a display device that projects the display image F from the display means 30 onto the windshield 101 and causes the driver 102 to visually recognize the virtual image V of the display image F. You may apply to the display apparatus which projects the display image from a display means on a reflective screen (projection member) or a transmission screen (projection member), and makes an observer visually recognize the real image of a display image. Moreover, although the HUD apparatus 100 of this embodiment was for vehicles, you may apply this invention to display apparatuses other than the object for vehicles.

  The present invention can be used for a display device and a display method thereof.

100 Head-up display device 101 Wind shield (projection member)
102 Driver (observer)
DESCRIPTION OF SYMBOLS 10 Imaging part 20 Control part 30 Display means 40 Concave mirror

Claims (8)

Display means for displaying a display image;
Display control means for displaying the display image on the display means;
A position detecting means capable of detecting an observer's viewpoint position, and projecting the display image onto a projection target member,
A first distortion correction parameter when the viewpoint position is the left end of the visible range of the display image; a second distortion correction parameter when the viewpoint position is the center of the visible range of the display image; A third distortion correction parameter when the viewpoint position is the right end of the visible range of the display image;
The display control means acquires one of the first to third distortion correction parameters based on the viewpoint position, or performs an interpolation process between two of the first to third distortion correction parameters. And calculating an interpolation distortion correction parameter to correct the distortion of the display image when projected onto the projection member based on any of the first to third distortion correction parameters or the interpolation distortion correction parameter. A display device characterized by:   The display control means performs interpolation processing between the first and second distortion correction parameters when the viewpoint position is located between the center and the left end of the visible range of the display image. When distortion correction parameters are calculated, and the viewpoint position is located between the center and the right end of the visible range of the display image, interpolation processing is performed between the second and third distortion correction parameters. The display device according to claim 1, wherein an interpolation distortion correction parameter is calculated. Display means for displaying a display image;
A position detection means capable of detecting a viewer's viewpoint position, and a display device display method for projecting the display image onto a projection target member,
A first distortion correction parameter when the viewpoint position is the left end of the visible range of the display image; a second distortion correction parameter when the viewpoint position is the center of the visible range of the display image; A third distortion correction parameter when the viewpoint position is the right end of the visible range of the display image;
Either one of the first to third distortion correction parameters is acquired based on the viewpoint position, or interpolation processing is performed by interpolating between two of the first to third distortion correction parameters. Calculating a parameter, and correcting distortion of the display image when projected onto the projection member based on any of the first to third distortion correction parameters or the interpolation distortion correction parameter. Display method of the display device.   When the viewpoint position is located between the center and the left end of the visible range of the display image, the interpolation distortion correction parameter is calculated by performing an interpolation process between the first and second distortion correction parameters. When the viewpoint position is located between the center and the right end of the viewable range of the display image, the interpolation distortion correction parameter is calculated by performing interpolation processing between the second and third distortion correction parameters. The display method of the display device according to claim 3, wherein: Display means for displaying a display image;
Display control means for displaying the display image on the display means;
A position detecting means capable of detecting an observer's viewpoint position, and projecting the display image onto a projection target member,
A first distortion correction parameter when the viewpoint position is at the upper end and the left end of the viewable range of the display image, and a second when the viewpoint position is at the upper end and the left and right center of the viewable range of the display image A distortion correction parameter, a third distortion correction parameter when the viewpoint position is the upper end and the right end of the viewable range of the display image, and the viewpoint position is the upper and lower center and the left end of the viewable range of the display image. The fourth distortion correction parameter in the case, the fifth distortion correction parameter in the case where the viewpoint position is the vertical center and the horizontal center of the display image viewable range, and the viewpoint position is the viewable range of the display image. And a seventh distortion correction parameter when the viewpoint position is the lower end and the left end of the viewable range of the display image. A meter, an eighth distortion correction parameter when the viewpoint position is the lower end and the center of the left and right of the display image, and the viewpoint position is the lower end and the right end of the display image A ninth storage unit for storing distortion correction parameters;
The display control means acquires any one of the first to ninth distortion correction parameters based on the viewpoint position, or interpolates between a plurality of the first to ninth distortion correction parameters. Then, the interpolation distortion correction parameter is calculated, and the distortion of the display image when projected onto the projection member is corrected based on any of the first to ninth distortion correction parameters or the interpolation distortion correction parameter. A display device characterized by:   The display control means, when the viewpoint position is located between the upper end, the left end, the upper end, the left / right center, the upper / lower center, the left end, the upper / lower center, and the left / right center of the visible range of the display image, , Second, fourth, and fifth distortion correction parameters are interpolated to calculate the interpolation distortion correction parameters, and the viewpoint position is the upper and lower center, the left end, the upper and lower center, and the left and right sides of the visible range of the display image. When it is located between the center and the lower end and between the left end and the lower end and the center of the left and right, the interpolation distortion correction parameter is calculated by interpolating between the fourth, fifth, seventh and eighth distortion correction parameters. And when the viewpoint position is located between the upper end, the left and right center and the upper end, the right end and the upper and lower center, and the left and right center and the upper and lower center and the right end of the visible range of the display image, the second, third, Fifth and sixth distortions The interpolation distortion correction parameter is calculated by interpolating between positive parameters, and the viewpoint position is a vertical center, a horizontal center, a vertical center, a right edge and a bottom edge, a horizontal center, a bottom edge, and a right edge of the viewable range of the display image. 6. The interpolated distortion correction parameter is calculated by interpolating between the fifth, sixth, eighth, and ninth distortion correction parameters when located in between. Display device. Display means for displaying a display image;
Display control means for displaying the display image on the display means;
A position detection means capable of detecting a viewer's viewpoint position, and a display device display method for projecting the display image onto a projection target member,
A first distortion correction parameter when the viewpoint position is at the upper end and the left end of the viewable range of the display image, and a second when the viewpoint position is at the upper end and the left and right center of the viewable range of the display image A distortion correction parameter, a third distortion correction parameter when the viewpoint position is the upper end and the right end of the viewable range of the display image, and the viewpoint position is the upper and lower center and the left end of the viewable range of the display image. The fourth distortion correction parameter in the case, the fifth distortion correction parameter in the case where the viewpoint position is the vertical center and the horizontal center of the display image viewable range, and the viewpoint position is the viewable range of the display image. And a seventh distortion correction parameter when the viewpoint position is the lower end and the left end of the viewable range of the display image. A meter, an eighth distortion correction parameter when the viewpoint position is the lower end and the center of the left and right of the display image, and the viewpoint position is the lower end and the right end of the display image A ninth storage unit for storing distortion correction parameters;
The display control means acquires any one of the first to ninth distortion correction parameters based on the viewpoint position, or interpolates between a plurality of the first to ninth distortion correction parameters. Then, the interpolation distortion correction parameter is calculated, and the distortion of the display image when projected onto the projection member is corrected based on any of the first to ninth distortion correction parameters or the interpolation distortion correction parameter. A display method for a display device. The display control means, when the viewpoint position is located between the upper end, the left end, the upper end, the left / right center, the upper / lower center, the left end, the upper / lower center, and the left / right center of the visible range of the display image, , Second, fourth, and fifth distortion correction parameters are interpolated to calculate the interpolation distortion correction parameters, and the viewpoint position is the upper and lower center, the left end, the upper and lower center, and the left and right sides of the visible range of the display image. When it is located between the center and the lower end and between the left end and the lower end and the center of the left and right, the interpolation distortion correction parameter is calculated by interpolating between the fourth, fifth, seventh and eighth distortion correction parameters. And when the viewpoint position is located between the upper end, the left and right center and the upper end, the right end and the upper and lower center, and the left and right center and the upper and lower center and the right end of the visible range of the display image, the second, third, Fifth and sixth distortions The interpolation distortion correction parameter is calculated by interpolating between positive parameters, and the viewpoint position is a vertical center, a horizontal center, a vertical center, a right edge and a bottom edge, a horizontal center, a bottom edge, and a right edge of the viewable range of the display image. 8. The interpolation distortion correction parameter is calculated by interpolating between the fifth, sixth, eighth, and ninth distortion correction parameters when the position is located between the fifth distortion correction parameter and the fifth distortion correction parameter. Display method of the display device.

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