JP2011105306A - Display device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To flexibly cope with a variation of eyepoints of drivers and a difference in shape between windshields when a virtual image projected on the windshield of a superimposition image displayed on a display source is viewed in a superimposed relation to a front view of a vehicle. <P>SOLUTION: When a virtual image of a superimposition reverse image reflected on three places on a windshield 3 in front of the eyepoint I, namely the virtual image of an original superimposition image, is visually identified in a superimposed relation to a front view visually identified through the windshield 3 by projecting on a windshield 3 the image light of a superimposition reverse image displayed on a screen 5a of a display device 5 inside a dashboard 1 of a vehicle, the superimposition reverse image displayed on the display device 5 is preliminarily distorted according to storage contents of an external ROM disposed in a control unit 7 and replaceable by the other with different storage contents so as to cancel the distortion generated when the image light of the superimposition reverse image is reflected on the windshield 3. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vehicle display device that projects an image for superimposition displayed on a display source onto a windshield, and superimposes a foreground of a vehicle visually recognized through the windshield and a virtual image of the image for superimposition. .

  In recent years, with the increase and diversification of information required by the driver during driving, information that cannot be displayed due to space in the meter unit is displayed as a virtual image on the windshield and viewed through it A projection type auxiliary display unit called a head-up display, which is superimposed on the foreground, is employed.

  In such a projection type auxiliary display unit, the windshield for projecting the display image of the display source is non-planar, and the curvature and the inclination angle with respect to the horizontal plane (or vertical plane) differ depending on the location of the windshield. Conventionally, it has been regarded as a problem that the virtual image display on the glass is distorted and adversely affects its visibility.

  Therefore, it has been proposed to correct the distortion of the virtual image on the windshield by using an optical element or display control. (For example, see Patent Document 1 and Patent Document 2.)

JP-A-3-113413 JP-A-4-283970

  However, in these conventional proposals, the seat position and physique are different depending on the driver, the position on the windshield that is visible from the eye point is not fixed, or the windshield shape varies depending on the vehicle type, Since it is not envisaged that the degree and content of the distortion of the virtual image viewed on the windshield will change depending on the situation, the correction of the distortion is performed in a uniform manner. It cannot respond flexibly to the situation.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to project an image for superimposition displayed on a display source onto a non-planar windshield, and to visually recognize the projected member. When the vehicle foreground and the virtual image of the image for superimposition are superimposed and viewed, the position on the windshield viewed from the eye point cannot be fixed at a certain location due to the difference in the seat position and physique by the driver, Even if the degree and content of virtual image distortion on the windshield changes due to the difference in the shape of the windshield due to the An object of the present invention is to provide a display device for a vehicle that can suitably eliminate distortion of a virtual image.

  To achieve the above object, the vehicle display device of the present invention includes a display device and a control unit that controls the content of an image to be displayed on the display device. An image for superimposition displayed on the display device is projected on the windshield of the vehicle, and the foreground of the vehicle viewed through the windshield from an eye point inside the vehicle, and the superimposition projected on the windshield. When superimposing and viewing the virtual image of the image for superimposition, the display device displays the distortion so that the distortion generated in the virtual image of the superimposition image viewed from the eye point due to the non-planarity of the windshield is offset. Display distortion generating means, and the display distortion generating means of the superimposed image to be displayed on the display device. A distortion pattern adjusting unit that adjusts a distortion amount in each of the vertical and horizontal directions of the vehicle in the virtual image of the superimposing image, and the display distortion generating unit converts the digital signal; According to the non-planarity of the windshield, and comprising a non-replaceable rewritable non-volatile memory storing in advance a coordinate conversion table according to the relative position of the windshield and the eye point, The strain pattern adjusting means is connected to the nonvolatile memory in accordance with the non-planarity of the windshield and the relative position of the windshield and the eye point with respect to the vehicle display device. Distortion that occurs in the virtual image of the superimposition image by rewriting the coordinate conversion table of the nonvolatile memory Thereby enabling cancellation, and wherein the.

  According to the vehicle display device of the present invention, the eye point in the vehicle changes due to the difference in the driver's seat position and physique, the degree of non-planarity and content of the windshield differ depending on the vehicle type, etc. Display distortion of the superimposed image displayed on the display device even if the degree and content of distortion due to the non-planarity of the windshield that occurs in the virtual image of the superimposed image on the windshield viewed from the eye point is not constant The distortion amount generated by the generating means is adjusted by the distortion pattern adjusting means in each of the vertical and horizontal directions of the vehicle in the virtual image of the superimposition image, and the distortion pattern is determined by adjusting the non-planarity of the windshield or the windshield and the eye. An image for superimposition on the windshield that is visible from the eye point by creating a distortion pattern according to the position relative to the point In a pattern corresponding to the degree or content of the distortion due to non-planarity of the windshield occurs to the virtual image, so that the superimposed image to be displayed on the display device is distorted by the display distortion generating means.

  Furthermore, according to the vehicle display device of the present invention, the coordinate conversion table of the non-volatile memory is rewritten, and at least the content of the coordinate conversion table is changed. The pixel in the image signal of the distortion superimposing image to which data is assigned is changed, and the content of the image signal of the distortion superimposing image generated by the conversion unit is changed. As a result, the image of the superimposing image to be displayed on the display device is changed. The distortion pattern by the display distortion generating means is changed and adjusted, and the configuration that enables rewriting of the coordinate conversion table of the nonvolatile memory constitutes the distortion pattern adjusting means.

  As described above, according to the vehicle display device of the present invention, in the vehicle display device including the display device and the control unit that controls the content of the image displayed on the display device, the control unit includes: The image for superimposition displayed on the display device is projected onto the windshield of the vehicle, and the foreground of the vehicle viewed through the windshield from an eye point inside the vehicle and the image projected onto the windshield Displayed on the display device so that distortion generated in the virtual image of the superimposing image viewed from the eye point due to the non-planarity of the windshield is canceled when the virtual image of the superimposing image is superimposed and visually recognized. Display distortion generating means for causing the display device to display the superimposing image to be displayed on the display device. A distortion pattern adjusting unit that adjusts the amount of distortion to be adjusted in each of the vertical and horizontal directions of the vehicle in the virtual image of the superimposing image, and the display distortion generating unit converts the digital signal; A non-replaceable rewritable non-volatile memory that stores in advance a coordinate conversion table according to the non-planarity of the windshield and the relative position of the windshield and the eye point, The strain pattern adjusting means is externally connected to the non-volatile memory according to the non-planarity of the windshield and the relative position of the windshield and the eye point with respect to the vehicle display device. Distortion that occurs in the virtual image of the superimposing image by rewriting the coordinate conversion table of the nonvolatile memory using a rewriting terminal. It was offset configured to be able to.

  For this reason, the distortion pattern of the superimposed image by the display distortion generating means is adjusted by the distortion pattern adjusting means to the distortion pattern according to the non-planarity of the windshield and the relative position of the windshield and the eye point. Due to the difference in seat position and physique by the person, the position on the windshield that is visible from the eye point cannot be fixed at a certain location, or due to the difference in the shape of the windshield depending on the model, etc. Even if the degree and content of the distortion of the virtual image of the superimposition image changes, the distortion of the virtual image of the superimposition image on the windshield can be suitably eliminated by flexibly responding to these situations Can do.

  By adjusting at least the contents of the coordinate conversion table held in the non-volatile memory of the display distortion generating means with the distortion pattern adjusting means, the position on the windshield viewed from the eye point cannot be determined at a certain location, or Due to the difference in the shape of the windshield due to, the degree of distortion of the virtual image on the windshield and the content of the image for superimposition on the windshield flexibly corresponding to the situation where the content changes It is possible to easily realize suitable elimination of the distortion of the virtual image.

It is sectional drawing which shows the fundamental schematic structure of the display apparatus for vehicles which concerns on the 1st example of an indication of this invention. FIG. 2 is an enlarged explanatory view showing a windshield irradiated with image light from the display device of FIG. 1 and its peripheral portion. It is a block diagram which shows the electrical schematic structure of the control unit of FIG. It is a flowchart which shows the processing operation which CPU performs according to the processing program stored in ROM by the digital data controller of the high-speed digital data conversion unit of FIG. It is a schematic diagram which shows the image for visual recognition of the instrument information from which an image signal is produced | generated in order to project on the windshield of FIG. FIG. 6 is a schematic diagram illustrating a virtual image of a superimposed inverted image that is assumed to be visually recognized on the windshield when the visual image of FIG. 5 is displayed on the display device of FIG. 1. It is a schematic diagram which shows the reverse image for a superimposition actually displayed on the display device of FIG. 1 in order to make an image without distortion like the image for visual recognition of FIG. 5 visually recognized on a windshield as a virtual image. It is a block diagram which shows the electrical schematic structure of the control unit in the display apparatus for vehicles which concerns on the 2nd example of an indication of this invention. It is a flowchart which shows the processing operation which CPU performs according to the processing program stored in ROM by the digital data controller of the high-speed digital data conversion unit of FIG. It is a block diagram which shows the electrical schematic structure of the control unit in the display apparatus for vehicles which concerns on 1st Embodiment of this invention. It is a block diagram which shows the electrical schematic structure of the control unit in the display apparatus for vehicles which concerns on 2nd Embodiment of this invention.

  Hereinafter, disclosure examples and embodiments of a display device for a vehicle according to the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing the basic schematic configuration of a vehicular display device according to a first disclosed example of the present invention. The vehicular display device according to the first disclosed example is an interior of a dashboard 1 of a vehicle. Display device 5 and a control unit 7 for controlling the content of an image displayed on the display device 5.

  Among these, the display device 5 includes a self-luminous device (for example, an FE [field emission] display, a fluorescent display tube, an EL [electroluminescence] display, etc.), a liquid crystal display with a backlight, and the like above the vehicle. A superimposed inverted image obtained by inverting an overlay image (not shown) such as auxiliary information necessary for driving, such as traveling direction information and traveling speed of the navigation device, is displayed on the display surface 5a. The upper side of the image is arranged on the rear side of the vehicle, and the lower side of the image for superimposing is arranged on the front side of the vehicle, so that light emission is displayed.

  Then, the image light of the superimposed inverted image displayed on the display device 5 passes through the opening 1b formed on the upper surface 1a of the dashboard 1 as shown in the enlarged perspective view of FIG. This is a reverse image of a foreground that is irradiated on a non-planar windshield 3 disposed above, and is viewed through the windshield 3 by this irradiation, and a superimposed reverse image displayed on the display device 5. The virtual image S of the image for superimposition is visually recognized from the eye point I of the driver of the vehicle.

  The control unit 7 is generated in a meter information generation unit (not shown) based on the detection statuses of various sensors (not shown) in the vehicle, as shown in a block diagram of an electrical schematic configuration in FIG. In addition, a signal input terminal 9 to which an image signal of a visual image of instrument information to be notified to the driver, such as a traveling speed, an engine speed, a remaining amount of fuel, and a radiator water temperature, is input. A synchronization signal separation circuit 10 that separates and extracts a synchronization signal from the received image signal, and an A / D conversion that performs A / D conversion on each pixel value of the image signal input to the signal input terminal 9 in order from the smallest coordinate value. And a high-speed digital data conversion unit (hereinafter abbreviated as “conversion unit”) 13 for processing a digital image signal in which each pixel value is A / D converted by the A / D converter 11. It is.

  The control unit 7 includes an external ROM 15 (corresponding to coordinate conversion table holding means) that stores a coordinate conversion table necessary for processing the digital image signal by the conversion unit 13, and a digital image processed by the conversion unit 13. An external RAM 17 as a video frame memory for temporarily storing each pixel value of the signal, and each pixel value of the processed digital image signal read from the external RAM 17 by the conversion unit 13 from the one having a small coordinate value. A D / A converter 19 that performs D / A conversion in order, and an analog image signal after each pixel value is D / A converted by the D / A converter 19 is displayed as an image signal of the superimposed image for superimposition. It has a signal output terminal 21 for outputting to the device 5.

  Among these, in the external ROM 15, the coordinate value of each pixel of the image signal of the visual image input to the signal input terminal 9 is associated with the image signal of the superimposed inverted image output from the signal output terminal 21. A coordinate conversion table associated with coordinate values to be stored is stored.

  The coordinate conversion table stored in the external ROM 15 is configured such that when the three windshields in front of the eye point I as a reference are visually recognized, the image for superimposing that is visually recognized on the three windshields. In order for the virtual image to be recognized as having no distortion, the superimposed inverted image to be displayed on the display device 5 is a relative positional relationship between the position of the reference eye point I and the three windshields in front thereof, the reference and This is for pre-distortion with a distortion pattern corresponding to the curvature of the windshield 3 in the horizontal and vertical directions in front of the eye point I and the inclination angle of the windshield 3 with respect to the horizontal plane (or vertical plane). is there.

  Therefore, for example, if the visual image represented by the image signal input to the signal input terminal 9 is a grid in which a plurality of vertical and horizontal straight lines intersect each other, the external ROM 15 displays this grid as it is. When displayed on the device 5, the coordinate values of the pixels respectively corresponding to the four corners of the lattice and the intersections of the vertical and horizontal straight lines, and the lattice that is visually recognized on the three windshields in front from the reference eye point I The four corners of the grid when the grid distorted in the direction opposite to the direction distorted by being projected onto the windshield 3 is displayed on the display unit 5a of the display device 5 in order to prevent the image of And coordinate values of pixels respectively corresponding to the intersections of the vertical and horizontal straight lines are held in association with each other.

  The conversion unit 13 is a digital data controller (hereinafter abbreviated as [DDC]) 13a configured by an ASIC (Application Specific Integrated Circuit) for high-speed coordinate conversion processing, and is necessary for high-speed coordinate conversion processing by the DDC 13a. A RAM 13b that provides a work area, a ROM 13c that stores a processing program executed to cause the DDC 13a to perform high-speed coordinate conversion processing, the synchronization signal separation circuit 10 that is connected to the DDC 13a, the A / D converter 11, An external ROM 15, an external RAM 17, and a CPU 13 d that controls access of the DDC 13 a to the D / A converter 19 are included.

  The processing operation performed by the DDC 13a in accordance with the processing program stored in the ROM 13c is performed as shown in the flowchart of FIG.

  That is, first, on the coordinate conversion table stored in the external ROM 15, the synchronization signal of the image signal of the visual image input to the signal input terminal 9 input from the synchronization signal separation circuit 10 is used as a sampling clock. Corresponding coordinate value in the image signal of the inverted image for superimposition that is associated with the coordinate value of each pixel in the image signal of the image for viewing is associated with a smaller coordinate value in the image signal of the image for viewing Are read in order (step S1).

  Next, in the external RAM 17, the data of the video frame portion of the coordinate value in the image signal of the superimposed inverted image read from the external ROM 15 in step S1 is digitally captured from the A / D converter 11 at that time. Whether or not the video frame data in the external RAM 17 has been rewritten with respect to pixel data for one screen of the digital image signal captured from the A / D converter 11 (step S3). (Step S5).

  If the video frame data in the external RAM 17 has not been completely rewritten for one screen of the digital image signal (N in step S5), the process returns to step S1, and if all the screens have been rewritten (in step S5). Y) The pixel data stored in the video frame of the external RAM 17 is read out for one screen in order from the smallest coordinate value in the image signal of the superimposed image for superimposition, and is read to the D / A converter 19. After outputting (step S7), the process returns to step S1.

  Next, the operation (action) of the vehicle display device of the first disclosed example configured as described above will be described.

  In the vehicular display device according to the first disclosed example, when a visual image of instrument information is displayed on the display device 5, the image light passes through the opening 1 b formed on the upper surface 1 a of the dashboard 1 and the dashboard. 1, the virtual image of the superimposing image is visually recognized on the three windshields in front of the eye point I.

  Here, since the windshield 3 is formed in a non-planar shape having curvatures in both horizontal and vertical directions, the reflection angle of the image light of the superimposing image from the display device 5 irradiated on the windshield 3 is as follows. The optical path length of the image light of the superimposed image from the display device 5 through the windshield 3 to the eye point I depends on the coordinate position on the display surface 5a of the display device 5. It will be different.

  Therefore, for simplification of description, the visual image of the instrument information for which the image signal is generated in the instrument information generation unit (not shown) is a grid-like image composed of vertical and horizontal straight lines as shown in FIG. Assuming that the three windshields in front of the eye point I are visually recognized, the inverted virtual image of the inverted image for superimposition displayed on the display device 5 is assumed to be visually recognized on the three windshields. The reflection on the windshield 3 causes distortion as if it was pulled in the lower right direction as shown in FIG.

  Therefore, in the vehicular display device according to the first disclosed example, when the three windshields in front of the eye point I are visually recognized, the virtual image of the superimposed inverted image visually recognized on the three windshields is not distorted. As described above, the following operation is performed.

  First, when an image signal of a visual image of instrument information generated in an instrument information generation unit (not shown) is input to the signal input terminal 9, each pixel value of the image signal of the visual image has a small coordinate value. The A / D converter 11 sequentially performs A / D conversion, and the digital value of each pixel of the image signal subjected to the A / D conversion is input to the conversion unit 13 in order from the smallest coordinate value.

  In parallel with this, when the image signal of the visual image is input to the signal input terminal 9, the synchronization signal is separated and extracted from the image signal in the synchronization signal separation circuit 10, and this synchronization signal is sent to the signal input terminal 9. Then, it is input to the conversion unit 13 as a clock signal.

  Then, in the conversion unit 13, each digital pixel value of the digital image signal of the image for viewing input from the A / D converter 11 in accordance with the synchronization signal input as the clock signal is the one having a small coordinate value. The video data is sequentially written on the video frame location of the external RAM 17 corresponding to the coordinate value location on the display unit 5 a of the display device 5, which is associated with the coordinate conversion table stored in the external ROM 15.

  The digital pixel values of the digital image signal of the visual image input from the A / D converter 11 are written in the video frame of the external RAM 17 for all coordinates, that is, for one screen of the visual image. Then, all the digital pixel values for one frame written in the video frame from the external RAM 17 are read in order from the smallest coordinate value on the video frame, and the D / A converter 19 performs D / A conversion. After A conversion, the signal is output from the signal output terminal 21 to the display device 5 as an analog image signal of the inverted image for superimposition.

  Then, on the display surface 5 a of the display device 5, the virtual image of the virtual superimposition image shown in FIG. 6 is inverted around the left and right (horizontal) axes, and the curvature of the windshield 3 in the horizontal and vertical directions is reversed. A reverse image for superimposition distorted into a shape as shown in FIG.

  Then, the image light of the reverse image for superimposition passes through the opening 1b formed on the upper surface 1a of the dashboard 1 and is irradiated onto the windshield 3 disposed above the dashboard 1, whereby FIG. When the image is distorted like a virtual image of the virtual inverted image for superimposition shown in FIG. 2, the distortion existing from the stage displayed on the display device 5 is renewed until the image light reaches the windshield 3 from the display device 5. As a result, when the three windshields in front of the eye point I are visually recognized, the image light of the inverted image for superimposition is reflected on the windshield 3 by the three windshields. The virtual image of the reversal image for superimposition that is visually recognized becomes a lattice-like image composed of original vertical and horizontal straight lines without distortion as shown in FIG.

  Therefore, in the vehicle display device of the first disclosed example, when the three windshields in front of the eye point I are visually recognized, the windshield is reflected on the three windshields and is visually recognized on the three windshields. The virtual image of the superimposing image has a non-planar shape in which the windshield 3 has nonuniformity in some places with respect to the curvature in the horizontal and vertical directions and the inclination angle of the windshield 3 with respect to the horizontal plane (or vertical plane). Even if it is a thing, it is visually recognized as a distortion-free image in both the horizontal and vertical directions, similarly to the lattice-like image shown in FIG.

  For this reason, the position on the windshield 3 viewed from the eye point I is not fixed at a certain position because the seat position and the physique are different depending on the driver, or the shape of the windshield 3 differs depending on the vehicle type. When the degree and content of the distortion of the virtual image of the image for superimposition visually recognized by the method changes depending on the situation, the external ROM 15 may be replaced with a storage content that differs depending on the situation of the change.

  As described above, according to the vehicle display device of the first disclosed example, the windshield 3 is irradiated with the image light of the superimposed inverted image displayed on the display surface 5a of the display device 5 in the dashboard 1 of the vehicle, By this irradiation, the virtual image of the inverted image for superimposition reflected on the three windshields in front of the eye point I, that is, the virtual image of the original image for superimposition is superimposed on the foreground viewed through the windshield 3. In order to visually recognize, the inverted image for superimposition to be displayed on the display device 5 is exchanged with a different stored content so that distortion generated when the image light of the inverted image for superimposition is reflected by the windshield 3 is offset. It is configured to be distorted in advance according to the stored contents of the possible external ROM 15.

  For this reason, by replacing the external ROM 15 with a different stored content, the position on the windshield 3 viewed from the eye point I is fixed at a fixed location due to the difference in the seat position and the physique by the driver. Even if the degree or content of the distortion of the virtual image of the superimposing image on the windshield 3 changes due to the difference in the shape of the windshield 3 depending on the vehicle type, etc. Corresponding to the flexibility, the distortion of the virtual image of the image for superimposition on the windshield 3 can be preferably eliminated.

  In the vehicle display device of the first disclosed example described above, the grid-like image formed of vertical and horizontal straight lines as shown in FIG. 5 becomes a distorted image as shown in FIG. Since the vertical and horizontal lines constituting the grid are displayed in an inclined manner on the display device 5, the distorted image is displayed on the display device 5 with the same resolution as when the image is not distorted. In order to display, it is necessary to make the pitch of adjacent pixels in that direction when tilted at a maximum of 45 ° the same as the pitch of adjacent pixels in the vertical and horizontal directions.

  In other words, if the pitch of adjacent pixels in the vertical and horizontal directions is 1, the pitch of the adjacent pixels in the direction inclined by 45 ° is 21/2, so that an image in which the number of pixels of the display device 5 is not distorted is displayed. Otherwise, the distorted image cannot be displayed on the display device 5 with the same resolution as when the image is not distorted. For example, the diagonal lines are displayed as vertical and horizontal lines in a staircase pattern. There is a possibility of being.

  Assuming such a case, if the display device 5 has a high resolution, the number of pixels of the display device 5 is larger than the number of pixels of the image signal of the image for visual recognition. The number of pixels of the image signal of the reverse image also increases to the same number as the number of pixels of the display device 5, but in this case, the coordinates stored in the external ROM 15 as in the vehicle display device of the first disclosed example. When the data of each pixel of the image for viewing input to the signal input terminal 9 is associated as the data of each pixel of the inverted image for superimposition output from the signal output terminal 21 using the conversion table, the inverted image for superimposition Pixels in which no data exists are generated in the image signal.

  Then, inevitably, it is necessary to perform data interpolation for each pixel of the superimposed inverted image in which no corresponding pixel exists in the image signal of the visual image.

  Therefore, a vehicle display device according to a second disclosed example of the present invention that can cope with such a situation will be described with reference to FIGS. 8 and 9.

  FIG. 8 is a block diagram of an electrical schematic configuration of a vehicle display device according to a second disclosed example of the present invention. The vehicle display device according to the second disclosed example is an exchangeable outer part of the control unit 7A. The contents stored in the attached ROM 15A (corresponding to the coordinate conversion table holding means) and the contents of the processing program stored in the ROM 13Ac of the conversion unit 13A are the external ROM 15 and the conversion unit 13 in the vehicle display device of the first disclosed example. Is different.

  The vehicle display device of the second disclosed example is the first in that each pixel value of the digital image signal before being processed by the conversion unit 13 is temporarily stored in the external RAM 17A of the control unit 7A. The configuration is different from the control unit 7 in the vehicle display device of the disclosed example.

  In the external ROM 15A of the vehicle display device according to the second disclosed example, among the pixels of the superimposed inverted image output from the signal output terminal 21, the visual image input to the signal input terminal 9 is output. For the image signal having a corresponding pixel, the coordinate value of the pixel of the image for visual recognition and the coordinate value of the corresponding pixel of the inverted image for superimposition are stored in association with each other.

  The processing operation performed by the DDC 13Aa according to the processing program stored in the ROM 13Ac is performed as shown in the flowchart of FIG.

  That is, first, the data of each video frame portion in the external RAM 17A is rewritten to the pixel data of the same coordinate value of the digital image signal fetched from the A / D converter 11 (step SA1), and then the A / D It is confirmed whether or not the video frame data in the external RAM 17A has been rewritten with respect to the pixel data for one screen of the digital image signal captured from the converter 11 (step SA3).

  If the video frame data of the external RAM 17 has not been completely rewritten for one screen of the digital image signal (N in step SA3), the process returns to step SA1, and if all of the screen has been rewritten (step SA3). Y) The coordinate value in the image signal of the image for visual recognition corresponding to the coordinate value in the image signal of the inverted image for superimposition on the coordinate conversion table stored in the external ROM 15A is the coordinate in the image signal of the inverted image for superimposition. The search is performed in order from the smallest value, and a pixel for which the corresponding coordinate value in the image signal of the image for visual recognition does not exist on the coordinate conversion table is extracted (step SA5).

  Then, the corresponding coordinate value in the image signal of the visual image extracted in step SA5 does not exist on the coordinate conversion table of the external ROM 15A, and corresponds to the peripheral coordinate value adjacent to the coordinate in the image signal of the superimposed inverted image. All the corresponding coordinate values in the image signal of the image for visual recognition in the coordinate conversion table of the external ROM 15A are calculated (step SA7), and then each corresponding coordinate value in the image signal of the image for visual recognition calculated. Are read from corresponding video frame locations in the external RAM 17A (step SA9), and the average of the data of these pixels is calculated (step SA11).

  Subsequently, in the image signal of the image for viewing other than that extracted in step SA5, using the synchronization signal of the image signal of the image for viewing input to the signal input terminal 9 input from the synchronization signal separation circuit 10 as the sampling clock. The pixel data corresponding to the coordinate value in the image signal of the inverted image for superimposition, in which the corresponding coordinate value exists on the coordinate conversion table of the external ROM 15A, is read from each corresponding video frame location in the external RAM 17A (step SA13), in the meantime, the pixel data corresponding to the coordinate value in the image signal of the inverted image for superimposition, in which the corresponding coordinate value in the image signal of the visual image does not exist on the coordinate conversion table of the external ROM 15A, Interpolation is performed by averaging the pixel data calculated in SA11 (step SA15).

  Then, the pixel data for one screen of the inverted image for superimposition after interpolation is output to the D / A converter 19 in order of increasing coordinate values in the image signal of the inverted image for superposition (step SA17), and then step SA1. Return to

  In the vehicle display device of the second disclosed example configured as described above, the image signal of the visual image of the instrument information generated in the instrument information generation unit (not shown) and input to the signal input terminal 9 is A The digital value of each pixel of the image signal which has been A / D converted by the / D converter 11 and A / D converted is written on the video frame portion of the corresponding external RAM 17 in order from the smallest coordinate value. .

  Then, on the coordinate conversion table stored in the external ROM 15A by the conversion unit 13A, the synchronization signal separated in the synchronization signal separation circuit 10 from the image signal of the visual image input to the signal input terminal 9 is used as a sampling clock. The pixel data of the coordinate value in the image signal of the inverted image for superimposition where the corresponding coordinate value in the image signal of the image for visual recognition exists is read out from the corresponding video frame location in the external RAM 17A.

  At the same time, the pixel data of other coordinate values in the image signal of the superimposed image for superimposition are determined by averaging the pixel data of the peripheral coordinate values and read from the corresponding video frame location in the external RAM 17A. The interpolated pixel data is interpolated and the digital pixel value for one screen after this interpolation is read in order from the smallest coordinate value in the image signal of the superimposed inverted image. After the D / A conversion, the signal is output from the signal output terminal 21 to the display device 5 as an analog image signal of the inverted image for superimposition.

  Similarly to the vehicle display device of the first disclosed example, the vehicle display device of the second disclosed example configured as described above can replace the external ROM 15A with a storage content different from that of the driver. Due to the difference in seat position and physique, the position on the windshield 3 viewed from the eye point I is not fixed at a certain location, or due to the difference in the shape of the windshield 3 depending on the vehicle model, etc. Even if the degree or content of the distortion of the virtual image on the superimposing image 3 changes, the distortion of the virtual image of the superimposing image on the windshield 3 can be flexibly adapted to these situations. Can be eliminated.

  In addition, in the vehicular display device according to the second disclosed example, the superimposed reverse image is used for visual recognition in response to intentionally distorting the visual image of the instrument information into the superimposed inverted image. In order to display on the display device 5 with the same resolution as the image, the number of pixels of the display device 5 is increased, and pixels having no pixel corresponding to the image signal of the visual image are generated in the image signal of the superimposed inverted image. Even in this case, the pixel data of the image signal of the inverted image for superimposition that does not have the corresponding pixel in the image signal of the image for viewing is interpolated, and the inverted image for superimposition is displayed on the display device 5 in a good state. Can be made.

  In each of the first and second disclosed examples described above, the external ROM 15 and 15A are replaced with ones having different stored contents. The degree and content of the distortion of the virtual image of the superimposing image on the windshield 3 due to the position on the windshield 3 to be visually recognized not being fixed at a certain place or the difference in the shape of the windshield 3 depending on the vehicle type. The configuration corresponds to the case where the change occurs.

  However, for example, a control unit 7B of the vehicle display device according to the first embodiment having a configuration corresponding to the vehicle display device of the first disclosed example shown in the block diagram of the electrical schematic configuration in FIG. In place of the replaceable external ROM 15, a rewritable nonvolatile memory (hereinafter abbreviated as “NVM”, which corresponds to the coordinate conversion table holding means) 15 B can be used instead of the non-replaceable external ROM 15. A replaceable external ROM 15A, such as the control unit 7C of the vehicle display device according to the second embodiment having a configuration corresponding to the vehicle display device of the second disclosed example, shown in a block diagram of a general schematic configuration Instead of this, a rewritable NVM 15C (corresponding to a coordinate conversion table holding unit) may be used instead of being non-exchangeable.

  In that case, the coordinate conversion tables stored in the NVMs 15B and 15C, respectively, or the rewriting terminal 23 (distortion pattern) connected to these from the outside of the control units 7 and 7A directly or via the conversion units 13 and 13A. By rewriting to something with different contents by adjusting means), the position on the windshield 3 viewed from the eye point I may not be fixed at a certain place due to the difference in seat position and physique by the driver. It is possible to cope with a case where the degree or content of the distortion of the virtual image of the superimposing image on the windshield 3 changes due to the difference in the shape of the windshield 3 depending on the vehicle type.

  In this case, while the rewriting terminal 23 is connected to the NVMs 15B and 15C, the inverted image for superimposition (corresponding to the distortion image for adjustment) in FIG. 7 is displayed on the display surface 5a of the display device 5. Then, the reversal virtual image of the reversal image for superimposition visually recognized on the windshield 3 is adjusted by a cursor operation on the rewriting terminal 23 side or the like so that it becomes a grid-like image composed of vertical and horizontal straight lines as shown in FIG. When the inverted virtual image of the superimposed inverted image on the windshield 3 becomes a grid-like image composed of vertical and horizontal straight lines shown in FIG. 5, the superimposed image displayed on the display surface 5a of the display device 5 at that time. The content of the coordinate conversion table is rewritten to the conversion units 13 and 13A so that the image signal of the reverse image is generated from the image signal of the visual image for the instrument information generated in the instrument information generation unit (not shown). Indexing the terminal 23 in Kano either, the contents of the indexing coordinate conversion table, NVM15B, may be configured to cause rewriting the stored contents of 15C.

  As is clear from the above description, in each of the first and second embodiments, the conversion unit 13 and the NVM 15B, or the conversion unit 13A and the NVM 15C constitute the display distortion generating means in the claims. become.

  In the vehicle display device according to each of the disclosure examples and the embodiments described above, the image light of the image displayed on the display device 5 is reflected once by the windshield 3 and guided to the eye point I. The reverse image is displayed on the device 5, and this applies in the same way when the image light of the image displayed on the display device 5 is reflected to the eye point I by being reflected an odd number of times three or more times. However, if the image light of the image displayed on the display device 5 is reflected two or more times and guided to the eye point I, an erect image is displayed on the display device 5.

  Further, in the vehicle display devices according to the disclosure examples and the embodiments described above, the case where the display device 5 is accommodated in the dashboard 1 has been described as an example. However, the present invention is directed to image light from the display device 5. As long as the image is projected on the windshield 3 and visually recognized from the eye point I, the present invention can be applied to a display device arranged outside the dashboard.

3 Windshield 5 Display device 13, 13A Conversion unit (distortion image signal generation means, display distortion generation means)
15B, 15C non-volatile memory (coordinate conversion table holding means, display distortion generating means)
23 Rewriting terminal (distortion pattern adjustment means)
I eye point S virtual image

Claims (1)

In a vehicle display device comprising a display device and a control unit that controls the content of an image displayed on the display device,
The control unit is
The image for superimposition displayed on the display device is projected onto the windshield of the vehicle, and the foreground of the vehicle viewed through the windshield from an eye point inside the vehicle and the image projected onto the windshield Displayed on the display device so that distortion generated in the virtual image of the superimposing image viewed from the eye point due to the non-planarity of the windshield is canceled when the virtual image of the superimposing image is superimposed and visually recognized. Display distortion generating means,
Distortion pattern adjusting means for adjusting the amount of distortion by the display distortion generating means of the superimposed image to be displayed on the display device in each of the vertical and horizontal directions of the vehicle in the virtual image of the superimposed image. ,
The display distortion generating means;
A conversion unit that processes digital signals;
According to the non-planarity of the windshield, and comprising a non-replaceable rewritable non-volatile memory storing in advance a coordinate conversion table according to the relative position of the windshield and the eye point,
The strain pattern adjusting means is externally connected to the non-volatile memory according to the non-planarity of the windshield and the relative position of the windshield and the eye point with respect to the vehicle display device. A vehicular display device, wherein a distortion occurring in a virtual image of the superimposing image can be canceled by rewriting a coordinate conversion table of the nonvolatile memory using a rewriting terminal.

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