JP2021103274A - Head-up display device - Google Patents

Abstract

To deter appearance of an image from changing instantly following update of a warping parameter and to deter a driver from having a feeling of incongruity when executing viewpoint position following warping control for updating a warping parameter according to a driver's viewpoint position.SOLUTION: A control part 180 for executing viewpoint position following warping control executes at least one of first control for maintaining a warping parameter before movement without updating it even if a viewpoint is moved when at least one of a driver's left and right viewpoints is positioned in a predetermined area, second control for reducing reflection of a warping parameter to an image displayed in a display part 116 relative to input of a viewpoint position, and third control for updating a warping parameter intermittently relative to movement of a driver's viewpoint.SELECTED DRAWING: Figure 4

Description

The present invention is a head-up display (HUD) device or the like that projects (projects) the display light of an image onto a projected member such as a windshield or a combiner of a vehicle and displays a virtual image in front of the driver or the like. Regarding.

In the HUD device, an image correction process (hereinafter referred to as warping process) in which the projected image is pre-distorted so as to have characteristics opposite to the distortion of the virtual image caused by the curved surface shape of the optical system, the windshield, etc. )It has been known. The warping process in the HUD apparatus is described in, for example, Patent Document 1.

Japanese Unexamined Patent Publication No. 2015-87619

The present inventor has examined the implementation of viewpoint position-following warping control that updates the warping parameters according to the viewpoint position of the driver (which can be widely interpreted by the driver, crew, etc.), and describes the new method described below. Recognized the challenge.

When the viewpoint position moves and the warping parameter is updated, the appearance of the virtual image seen by the driver (the state of the virtual image, the impression received from the virtual image, etc.) changes instantaneously even if the virtual image of the same image is displayed. It may cause a sense of discomfort to the driver.

Ideally, the image (virtual image) displayed after the warping process should be a flat virtual image after the distortion caused by the optical system or the like is completely corrected. In the viewpoint position tracking warping, the driver (user) Ideally, a distortion-free virtual image should always be obtained, even when the position of the viewpoint changes, but the distortion cannot be completely removed.

In particular, in recent years, for example, a HUD device capable of displaying a virtual image over a considerably wide range in front of a vehicle has been developed, and such a HUD device tends to be large in size. Although the optical system and other designs have been devised to reduce distortion, for example, it is difficult to achieve a uniform distortion reduction effect in the entire area of the eyebox. For example, the driver's point of view is the eye. It is undeniable that the degree of distortion can be suppressed considerably when it is in the central region of the box, but the degree of residual distortion increases to some extent when the viewpoint is around the eyebox.

For example, if the viewpoint is moved while the driver's viewpoint is located in the peripheral area of the eyebox, which is easily affected by the change in the appearance of the virtual image due to the warping process, the image (even if the displayed contents are the same) The appearance of the virtual image) changes considerably, and the change occurs instantaneously in response to the movement of the viewpoint, which may cause the driver to feel uncomfortable.

One of the objects of the present invention is that when the viewpoint position tracking warping process is performed in the HUD device, the appearance of the image changes instantaneously with the update of the warping parameters, causing the driver to feel uncomfortable. It is to suppress.

Other objects of the invention will become apparent to those skilled in the art by reference to the embodiments and best embodiments illustrated below, as well as the accompanying drawings.

Hereinafter, in order to easily understand the outline of the present invention, embodiments according to the present invention will be illustrated.

In the first aspect, the head-up display device is
A head-up display (HUD) device that is mounted on a vehicle and projects an image onto a projected member provided on the vehicle so that the driver can visually recognize a virtual image of the image.
An image generator that generates the image and
A display unit that displays the image and
An optical system including an optical member that reflects the display light of the image and projects it onto the projected member.
The warping parameter is updated according to the viewpoint position of the driver in the eye box, and the image displayed on the display unit using the warping parameter is pre-distorted so as to have a characteristic opposite to the distortion characteristic of the virtual image of the image. A control unit that performs warping control following the viewpoint position
Have,
The control unit
When at least one of the driver's left and right viewpoints is located in a predetermined area, the first control that maintains the warping parameter before the movement without updating even if the viewpoint moves.
as well as,
A second control that slows down the reflection of the warping parameter on the image displayed on the display unit with respect to the viewpoint position input.
as well as,
A third control that intermittently updates the warping parameter with respect to the movement of the driver's viewpoint.
At least one of the above is carried out.

In the first aspect, in order to suppress the adverse effect that the appearance of the image (virtual image) changes and causes a sense of discomfort due to the viewpoint position tracking warping process, for example, a condition is set and the condition is satisfied. Take measures such as slowing down the sensitivity of the warping process.

In the first control, when the viewpoint is located in a predetermined area of the eye box, the warping process is not performed even if the viewpoint moves, and the sensitivity of the warping process is lowered.

Further, in the second control, the reflection of the warping parameter on the image (virtual image) display is blunted (delayed) instead of performing the image correction by the immediately updated warping parameter following the movement of the viewpoint. Decrease the sensitivity of the warping process.

Further, in the third control, intermittent (in other words, non-continuous) warping processing is performed. For example, in an area with an eyebox, if the viewpoint repeatedly moves a predetermined distance in a predetermined direction, the warping parameter is updated for each movement (continuous update of the warping parameter), but other areas of the eyebox. Then, the warping parameter is not updated even if the viewpoint moves in the predetermined direction and at a predetermined distance, and the rule that the warping parameter is updated for each movement is violated and discontinuous (warping). Controls such as (parameters are updated intermittently) are performed to reduce the sensitivity of the warping process.

The above-mentioned first to third controls can be used in combination as appropriate, whereby the degree of decrease in sensitivity of the warping process and the mode of decrease can be appropriately adjusted.

In the second aspect, which is subordinate to the first aspect,
The control unit receives the first control when performing the first control.
The inside of the eye box may be divided into a central region and a peripheral region, and even if the viewpoint moves when the viewpoint is located in the peripheral region, the warping parameter may be maintained without being updated. ..

In the second aspect, the first control is performed when the driver's viewpoint position is in the peripheral region of the eyebox. As mentioned earlier, it is difficult to achieve a uniform distortion reduction effect in all areas of the eyebox, for example, even if the degree of distortion can be significantly suppressed when the driver's viewpoint is in the central area of the eyebox. When the viewpoint is around the eye box, it is undeniable that the degree of residual distortion increases to some extent. For example, if the viewpoint is moved while the driver's viewpoint is located in the peripheral area of the eyebox, which is easily affected by the change in the appearance of the virtual image due to the warping process, the image (even if the displayed contents are the same) The appearance of the virtual image) changes considerably, and the change occurs instantaneously in response to the movement of the viewpoint, and the driver tends to feel uncomfortable.

Therefore, in the second aspect, when the driver's viewpoint position is in the peripheral region of the eyebox, even if the viewpoint movement occurs, the viewpoint movement is ignored and the warping parameter is not updated, so that the image ( It suppresses adverse effects such as discomfort caused by a considerably large change in the appearance of the virtual image).

In the third aspect, which is subordinate to the first aspect,
The control unit receives the second control when performing the second control.
When the viewpoint moves from the first position to the second position, the warping parameter is reflected on the image displayed on the display unit for a predetermined time from the time when the movement to the second position is detected. Perform the first process to delay,
Or
When the first process is performed and the predetermined time elapses and the viewpoint remains at the second position, the warping parameter corresponding to the second position is displayed. Perform the second process to reflect in the image,
Or
The inside of the eye box may be divided into a central region and a peripheral region, and the first process or the second process may be performed only when the viewpoint is in the peripheral region.

In the third aspect, as a case where the above-mentioned second control (control for blunting the reflection of the warping parameter in the displayed image) is performed, specifically, any one of the first to third processes is performed. Can be carried out.

In the first process, when the viewpoint moves, the reflection of the new warping parameter on the image is delayed by a predetermined time to prevent the image (virtual image) from changing instantaneously following the viewpoint. To reduce discomfort.

In the second process, in addition to the first process, it is confirmed whether the viewpoint stays at the same position after a lapse of a predetermined time, and a new warping parameter is reflected in the image only when the viewpoint stays. To do. For example, while driving a vehicle, it can be assumed that the driver's viewpoint moves instantaneously over a fairly wide range for some reason. Even in such a case, if the second process is performed, the viewpoint moves. When it is inside, the warping parameters are not updated, and when it is detected that the movement is completed and the position of the viewpoint is stable, the image can be corrected by the updated warping parameters, and therefore the image ( It is suppressed that the appearance of the virtual image) changes one after another and a sense of discomfort occurs.

Further, in the third process, the first and second processes are performed only when the viewpoint moves when the viewpoint is in the peripheral area of the eyebox. As a result, when the viewpoint is in the peripheral region, which is considered to have a large change in the appearance of the image (virtual image) due to the update of the warping parameter, the third process is performed to instantly see the image (virtual image). It is possible to suppress the change one after another.

In the fourth aspect, which is subordinate to the first aspect,
The control unit receives the third control when performing the third control.
When the viewpoint moves in a predetermined direction from the current position by a predetermined distance, it is considered that the viewpoint has moved to another position different from the current position, and the warping parameter is updated to the warping parameter corresponding to the other position. But,
Even if the viewpoint moves from the other position in the predetermined direction by the predetermined distance and the viewpoint moves to another position different from the other position, the update to the warping parameter corresponding to the other position is performed. Do not carry out
Or
As the eye box, an eye box of a coarse / dense division method in which the center is densely divided and the periphery is roughly divided is adopted, the position of the viewpoint is determined in units of each partial region, and the viewpoint tracking warping control is performed. You may.

In the fourth aspect, two specific methods can be adopted as the case where the above-mentioned third control (control for intermittently reflecting the warping parameter on the displayed image) is performed. One is, for example, when the viewpoint repeatedly moves in a predetermined direction by a predetermined distance, regardless of the division method inside the eyebox, for example, in a certain section, the warping parameter is updated for each movement. However, when the viewpoint moves further and becomes a different section, the warping parameter is not updated for each movement, so that the warping parameter is updated with, without, or with, and so on, which is not continuous. In other words, intermittent updates are carried out. As a result, the sensitivity of the warping correction process (which can also be called the sensitivity of viewpoint detection) is lowered, and the occurrence of discomfort due to the change in the appearance of the image (virtual image) due to the update of the warping parameter is suppressed.

The other one uses an eyebox having a dense and dense partial region in the center and sparse in the periphery, determines the position of the viewpoint in units of each partial region, and implements viewpoint tracking warping control. In terms of determining the viewpoint position in units of partial regions, it is common to both the center and the periphery of the eyebox, but in the periphery, the area of one partial region is large, so even if the viewpoint moves a little, the adjacent next It is less likely that the line of sight will shift to a partial area. Therefore, the frequency of detecting the movement of the viewpoint is reduced, and the frequency of updating the warping parameter is suppressed accordingly.

In the fifth aspect, which is subordinate to any one of the first to fourth aspects,
Further, it has a low-speed state determination unit for determining whether or not the speed of the vehicle is a low-speed state.
The control unit may perform at least one of the first control, the second control, and the third control when the vehicle is in the low speed state including the stopped state.

In the fifth aspect, at least one of the first to third controls is performed when the vehicle is in a low speed state. When the vehicle is in a low speed state, the driver is sensitive to visual fluctuations such as in front of the driver and can easily detect the fluctuations. Therefore, at this time, by performing the above control, it is possible to reduce the sensitivity of updating the warping parameter and suppress the occurrence of a sense of discomfort due to a change in the appearance of the image (virtual image).

In the sixth aspect, which is subordinate to any one of the first to fourth aspects,
The eye box is divided into a plurality of partial regions at the initial stage when the head-up display device is in an operating state.
The control unit
The position of the viewpoint is determined using each partial region of the eye box as a unit, and the position of the viewpoint is determined.
By increasing the number of the partial regions in the entire eye box in response to the increase in the speed of the vehicle, the resolution of detecting the viewpoint position is improved, and in increasing the number of the partial regions, the said As the speed of the vehicle increases, the range of the dense subregion may be expanded from the center to the periphery of the eyebox.

In the sixth aspect, control is performed in which the range of dense subregions is expanded from the center of the eyebox to the periphery to increase the number of subregions in response to the increase in vehicle speed (in other words, the above). Control to reduce the range that suppresses the sensitivity of updating the warping parameter) is implemented.

As the speed of the vehicle increases, it becomes difficult for the driver to recognize the discomfort. Therefore, the area for taking measures against the discomfort is reduced as the speed increases. Then, the distortion of the display due to the small movement of the viewpoint is corrected by the warping process, and the display process with more emphasis on the visual sense is performed.

In the seventh aspect, which is subordinate to the sixth aspect,
When the speed of the vehicle is within the range of the first speed value U1 (U1> 0) or more and the second speed value U2 or less, which is larger than the second speed value, the control unit is used. When the speed of the vehicle is less than the first speed value, and when the speed of the vehicle is less than the first speed value, the control for improving the detection resolution of the viewpoint position corresponding to the increase in the speed of the vehicle is performed. When it is larger than the value, the resolution of detecting the viewpoint position may be kept constant.

In the seventh aspect, the resolution of detecting the viewpoint position corresponding to the increase in the vehicle speed is improved in the predetermined range of the vehicle speed (the range in which U1 ≦ U ≦ U2 is satisfied for the vehicle speed U). Implement control. Further, if the above control is to be applied even when the vehicle speed is smaller than U1 and larger than U2, the burden on the HUD device (control unit) becomes heavy, so the control is not performed within that range. Care is taken not to put an unreasonable burden on the device.

In the eighth aspect, which is subordinate to the seventh aspect,
In carrying out the control for improving the resolution of the detection of the viewpoint position corresponding to the increase in the speed of the vehicle.
In the range where the vehicle speed is close to the first speed value, the degree of improvement in resolution is moderated, and as the vehicle speed moves away from the first speed value, the degree of improvement in resolution is steepened.
Or
In the range where the vehicle speed is close to the first speed value, the degree of improvement in resolution is moderated, and as the distance from the first speed value increases, the degree of improvement in resolution is controlled to be steeper, and the vehicle speed is controlled. May be controlled to slow down the degree of improvement in the resolution as the speed approaches the second speed value.

In the eighth aspect, when the resolution (detection sensitivity) of detecting the viewpoint position in the eyebox is improved in response to the increase in vehicle speed, the driver is likely to perceive a visual change in the image (virtual image) in a low speed state. (In other words, when the vehicle speed is in the range close to the first speed value U1), the degree of increase in the detection resolution (detection sensitivity) is gradual so as to suppress the sudden update of the warping parameter. Control is performed, or in addition to the control, control is performed to moderate the degree of increase in the detection resolution (detection sensitivity) as the second speed value U2 is approached. Then, when the second speed value U2 is reached, the detection resolution (detection sensitivity) is saturated and becomes constant, so that the change suddenly (suddenly) peaks out and a sense of discomfort is suppressed. .. With these controls, the visibility of the virtual image can be further improved.

In the ninth aspect, which is subordinate to any one of the first to eighth aspects,
The head-up display device is
When adjusting the position of the eye box according to the height position of the viewpoint of the driver, the reflection position of the display light of the image on the optical member is changed without moving the optical member.

In the ninth aspect, the HUD device that implements the above control projects light onto the projected member when adjusting the height position of the eyebox according to the height position of the driver's eyes (viewpoint). This is done by changing the light reflection position of the optical member without rotating the optical member using, for example, an actuator.

Recent HUD devices tend to be developed on the premise of displaying a virtual image over a fairly wide area in front of the vehicle, for example, and in this case, the device is inevitably enlarged. Naturally, the optical member also becomes large. If this optical member is rotated by using an actuator or the like, the accuracy of controlling the height position of the eyebox may rather decrease due to the error, and in order to prevent this, light rays are reflected by the optical member. It was decided to respond by changing the position.

In such a large optical member, the distortion of the virtual image is prevented from becoming apparent as much as possible by optimally designing the reflecting surface as a free curved surface, but as described above, for example, around the eye box. When the driver's viewpoint is located, distortion may inevitably become apparent. Therefore, in such a case, by performing control such as lowering the sensitivity of updating the warping parameter, it is possible to prevent a sense of discomfort due to a change in appearance due to distortion of the virtual image, and the above control can be performed. It can be effectively used to improve visibility.

In a tenth aspect subordinate to any one of the first to ninth aspects,
A virtual virtual image display surface corresponding to the image display surface of the display unit is arranged so as to overlap the road surface in front of the vehicle.
Or
The distance between the near end portion of the virtual image display surface on the side closer to the vehicle and the road surface is small, and the distance between the far end portion on the far side from the vehicle and the road surface is large. In addition, it is arranged at an angle with respect to the road surface.

In the tenth aspect, in the HUD device, a virtual virtual image display surface (corresponding to a display surface such as a screen as a display unit) arranged in front of the vehicle or the like is superimposed on the road surface, or It is installed at an angle with respect to the road surface. The former is sometimes referred to as a road surface superimposition HUD, and the latter is sometimes referred to as an inclined surface HUD.

These can perform various displays in the range of 5 m to 100 m in front of the vehicle, for example, by using a wide virtual image display surface superimposed on the road surface or a wide virtual image display surface provided at an angle with respect to the road surface. Therefore, it is preferable that the HUD device is enlarged and the eye box is also enlarged, the viewpoint position is detected with high accuracy in a wider range than before, and image correction using appropriate warping parameters is performed. In this case, for example, when the viewpoint is around the eye box, the visibility of the image (virtual image) may decrease due to frequent updates of the warping parameters. Therefore, the control method of the present invention can be applied. It becomes valid.

Those skilled in the art will readily appreciate that the embodiments according to the present invention exemplified may be further modified without departing from the spirit of the present invention.

FIG. 1 (A) is a diagram for explaining an outline of the warping process and a mode of distortion of a virtual image (and a virtual image display surface) displayed through the warping process, and FIG. 1 (B) is a diagram for explaining a mode of distortion of a virtual image (and a virtual image display surface) displayed through the warping process. It is a figure which shows an example of the virtual image which a driver visually recognizes. FIG. 2A is a diagram for explaining the outline of the viewpoint position tracking warping process, and FIG. 2B is a diagram showing a configuration example of an eyebox whose inside is divided into a plurality of partial regions. 3 (A) to 3 (F) are diagrams showing examples of virtual images having different distortions after the warping process. FIG. 4 is a diagram showing an example of the system configuration of the HUD device. FIG. 5 (A) is a diagram showing an example of viewpoint movement in an eyebox whose interior is divided into a plurality of partial regions, and FIG. 5 (B) is a diagram showing warping parameters for each viewpoint movement shown in FIG. 5 (A). It is a figure which shows the example of the presence or absence of an update in a tabular form. It is a timing chart which shows an example of the control which dulls the reflection of a warping parameter in an image. 7 (A) and 7 (B) are diagrams showing a configuration example of a coarse-dense division type eye box. FIG. 8A is a diagram showing another configuration example of the coarse / dense division type eyebox, and FIG. 8B is a diagram showing a configuration example of the eyebox in which the dense portion region is increased to the upper limit. FIG. 9 is a diagram showing an example of characteristics in control for changing the viewpoint detection sensitivity (viewpoint detection resolution) of the eyebox according to the vehicle speed. FIG. 10 is a flowchart showing a procedure example of the first warping image correction control (first control). FIG. 11 is a flowchart showing a procedure example of the second warping image correction control (second control). FIG. 12 is a flowchart showing a procedure example of the third warping image correction control (third control). FIG. 13 is a flowchart showing a procedure example of the fourth warping image correction control (fourth control). FIG. 14 (A) is a diagram showing a display example by the road surface superimposition HUD, FIG. 14 (B) is a diagram showing a display example by the inclined surface HUD, and FIG. 14 (C) is a configuration example of a main part of the HUD device. It is a figure which shows.

The best embodiments described below have been used to facilitate understanding of the present invention. Therefore, one of ordinary skill in the art should note that the present invention is not unreasonably limited by the embodiments described below.

See FIG. FIG. 1A is a diagram for explaining an outline of the warping process and a mode of distortion of a virtual image (and a virtual image display surface) displayed through the warping process, and FIG. 1B is a diagram for explaining a mode of distortion of a virtual image (and a virtual image display surface) displayed through the warping process. It is a figure which shows an example of the virtual image which a driver visually recognizes.

As shown in FIG. 1A, the HUD device 100 includes a display unit (for example, a light transmitting screen) 101, a reflecting mirror 103, and a curved mirror (for example, a concave mirror) as an optical member for projecting the display light. Yes, the reflective surface may be a free curved surface) 105. The image displayed on the display unit 101 is projected onto the virtual image display area 5 of the windshield 2 as a projected member via the reflecting mirror 103 and the curved mirror 105. In FIG. 1, reference numeral 4 indicates a projection region. The HUD 100 may be provided with a plurality of curved mirrors, in addition to the mirror (refractive optical element) of the present embodiment, or in place of a part (or all) of the mirror (refracting optical element) of the present embodiment. It may include a refraction optical element such as a lens and a functional optical element such as a diffractive optical element.

A part of the display light of the image is reflected by the windshield 2, and the driver or the like located inside (or on the EB) the preset eye box (here, the shape is a quadrangle having a predetermined area). The virtual image V is displayed on the virtual virtual image display surface PS corresponding to the display surface 102 of the display unit 101 by being incident on the viewpoint (eye) A of the above and forming an image in front of the vehicle 1.

The image of the display unit 101 is distorted due to the influence of the shape of the curved mirror 105, the shape of the windshield 2, and the like. In order to cancel the distortion, a distortion having the opposite characteristic to the distortion is given to the image. This pre-distortion (pre-distortion) type image correction is referred to as a warping process or a warping image correction process in the present specification.

Ideally, the virtual image V displayed on the virtual image display surface PS by the warping process becomes a flat image without curvature. For example, the display light is projected onto the wide projection area 4 on the windshield 2. In a large HUD device 100 or the like in which the virtual image display distance is set in a considerably wide range, it is undeniable that some distortion remains, which is unavoidable.

In the upper left of FIG. 1, PS'shown by a broken line indicates a virtual image display surface in which distortion is not completely removed, and V'indicates a virtual image displayed on the virtual image display surface PS'.

Further, the degree of distortion or the mode of distortion of the virtual image V in which the distortion remains differs depending on the position of the viewpoint A on the eyebox EB. Since the optical system of the HUD device 100 is designed on the assumption that the viewpoint A is located near the central portion, the distortion of the virtual image is relatively small when the viewpoint A is near the central portion, and the distortion of the virtual image is relatively small in the peripheral portion. Indeed, the distortion of the virtual image tends to increase.

FIG. 1B shows an example of a virtual image V visually recognized by the driver through the windshield 2. In FIG. 1B, the virtual image V having a rectangular outer shape has, for example, five reference points (reference pixel points) G (i, j) vertically and five horizontally, for a total of 25 reference points (reference pixel points) G (i, j). i and j are both variables that can take values 1 to 5). For each reference point in the image (original image), a distortion having a characteristic opposite to the distortion generated in the virtual image V due to the warping process is given, and therefore, ideally, the distortion given in advance and the distortion actually generated occur. The distortion is offset and ideally a non-curved virtual image V as shown in FIG. 1 (B) is displayed. The number of reference points G (i, j) can be appropriately increased by interpolation processing or the like. In FIG. 1B, reference numeral 7 is a steering wheel.

Next, refer to FIG. FIG. 2A is a diagram for explaining the outline of the viewpoint position tracking warping process, and FIG. 2B is a diagram showing a configuration example of an eyebox whose inside is divided into a plurality of partial regions. In FIG. 2, the same reference numerals are given to the parts common to those in FIG. 1 (this point is the same in the following figures).

As shown in FIG. 2A, the eyebox EB is divided into a plurality of (here, 9) subregions Z1 to Z9, and the driver's viewpoint A is set in units of the subregions Z1 to Z9. The position of is detected.

The display light K of the image is emitted from the projection optical system 118 of the HUD device 100, and a part of the display light K is reflected by the windshield 2 and incident on the driver's viewpoint (eye) A. When the viewpoint A is in the eye box, the driver can visually recognize the virtual image of the image.

The HUD device 100 has a ROM 210, and the ROM 210 includes an image conversion table 212. The image conversion table 212 stores, for example, a warping parameter WP that determines a polynomial, a multiplier, a constant, or the like for image correction (warping image correction) by a digital filter. The warping parameter WP is provided corresponding to each of the partial regions Z1 to Z9 in the eyebox EB. In FIG. 2A, WP (Z1) to WP (Z9) are shown as warping parameters corresponding to each partial region. In the figure, only WP (Z1), WP (Z4), and WP (Z7) are shown as reference numerals.

When the viewpoint A moves, the position of the viewpoint A in the plurality of partial regions Z1 to Z9 is detected. Then, any of the warping parameters WP (Z1) to WP (Z9) corresponding to the detected partial area is read from the ROM 210 (warping parameter update), and the warping process is performed using the warping parameters.

FIG. 2B shows an eyebox EB in which the number of partial regions is increased as compared with the example of FIG. 2A. The eyebox EB is divided into a total of 60 subregions, 6 in the vertical direction and 10 in the horizontal direction. Each subregion is displayed as Z (X, Y) with each coordinate position in the X direction and the Y direction as a parameter.

Further, in the example of FIG. 2B, the 12 partial regions (white regions) inside the thick line rectangle C are the central portion (central region) ZA, and the outer regions (with diagonal lines). (Shown) is a peripheral portion (peripheral region) ZB, and both are recognized (detected) separately for adjusting the sensitivity of the warping process according to the present invention.

Next, refer to FIG. 3 (A) to 3 (F) are diagrams showing examples of virtual images having different distortions after the warping process. As described above, the appearance of the virtual image V after the warping process differs depending on the position of the driver's viewpoint A in the eye box.

As shown in FIG. 3A, it is ideal that the virtual image V displayed in the virtual image display area 5 of the windshield 2 is displayed in a mode in which distortion is removed and there is no curvature. However, distortion remains in the actual virtual image V even after the warping process is performed, and the degree and mode of the distortion changes depending on the position of the viewpoint A.

In the example of FIG. 3 (B), although there is distortion, the distortion is relatively light, and the virtual image V looks similar to that of FIG. 3 (A). In the example of FIG. 3 (C), the tendency of distortion can be said to be the same as that of FIG. 3 (B), but the degree of distortion is large, and it cannot be said that the appearance is the same as that of FIG. 3 (A).

Further, in the example of FIG. 3 (D), the degree of distortion is the same as that of FIG. 3 (C), but the mode of distortion (the tendency of distortion or the mode of appearance of a virtual image after distortion occurs) is different. It is different from FIG. 3 (C).

In the example of FIG. 3 (E), the degree of distortion is larger and the left and right of the virtual image V is not balanced. In the example of FIG. 3 (F), the virtual image V has a tendency of distortion similar to that of FIG. 3 (E), but the appearance is considerably different from that of FIG. 3 (F).

As described above, even the virtual image V (virtual image V after the warping process) displaying the same contents has a considerably different appearance depending on the position of the viewpoint A. For example, when the viewpoint A is located at the center of the eyebox, the visually recognized virtual image V has relatively little distortion as shown in FIG. 3B, but when the viewpoint A moves from the center to the periphery, For example, as shown in FIG. 3 (E), the distortion becomes relatively large.

In this state (in the case of FIG. 3 (E) in which the viewpoint A is located in one partial region of the peripheral portion of the eye box), for example, the viewpoint A moves to another partial region, and for example, FIG. 3 ( Assuming a case where the appearance of the virtual image V changes as shown in B) (change a1) or a case where the appearance changes as shown in FIG. 3 (F) (change a2), the appearance changes in both cases. , It has changed considerably, and the possibility that the driver (user) will feel uncomfortable increases.

In other words, when the viewpoint A is in the peripheral area of the eyebox EB (the area ZB shaded in FIG. 2C), when the warping parameter is updated and a new warping process is performed, that viewpoint is obtained. Whether the movement is from one area of the peripheral area of the eyebox EB to another, or from one of the peripheral areas of the eyebox EB to one of the central areas, its warping. However, it can be said that the change in the appearance (appearance) of the virtual image V is greatly affected, and the change in the image can be easily visually recognized by the driver. Therefore, in particular, regarding the warping for the viewpoint movement that occurs when the viewpoint A is located in the peripheral region of the eyebox EB, it is effective to effectively reduce the occurrence of discomfort due to the instantaneous switching of the appearance of the virtual image V. ..

Next, refer to FIG. FIG. 4 is a diagram showing an example of the system configuration of the HUD device. The vehicle 1 is provided with a viewpoint detection camera 110 that detects the position of the driver's viewpoint A (eyes, pupils). Further, the vehicle 1 is provided with an operation unit 130 to enable the driver to set necessary information in the HUD device 100, and various information of the vehicle 1 can be collected. A vehicle ECU 140 is provided.

Further, the HUD device 100 includes a light source 112, a light projecting unit 114, a projection optical system 118, a viewpoint position detection unit (viewpoint position determination unit) 120, a bus 150, a bus interface 170, and a display control unit 180. It has an image generation unit 200, a ROM 210 having a built-in image conversion table 212, and a VRAM 220 that stores image (original image) data 222 and temporarily stores image data 224 after warping processing. ..

The viewpoint position detection unit 120 detects (determines) which part region in the eyebox the viewpoint A is located based on the viewpoint coordinate detection unit 122 and the detected coordinates, and the partial area detection unit in the eyebox. It has 124 and.

Further, the display control unit 180 includes a speed detection unit (which also serves as a low speed state determination unit for determining a low speed state) 182 for detecting (determining) the speed of the vehicle 1 and a warping control unit 184 (which includes a warping management unit 185). , A timer 190, a memory control unit 192, and a warping processing unit (warping image correction processing unit) 194.

Further, the warping management unit 185 includes (a peripheral viewpoint detection unit 186 for detecting that the viewpoint A is in the peripheral region of the eye box, and a temporary storage unit 188 for partial area information of the eye box.

The basic operation is as follows. That is, the memory control unit 192 accesses the ROM 210 and responds by using the partial area information (information indicating which partial area of the eyebox the viewpoint A is in) sent from the viewpoint position detection unit 120 as an address variable. The warping parameter is read out, and the warping processing unit (warping image correction processing unit) 194 performs warping processing on the original image using the read warping parameter, and the image generation unit 200 is based on the data after the warping processing. An image of a predetermined format is generated at the above, and the image is supplied to, for example, a light source 112, a light projecting unit 114, or the like.

However, if warping is performed by simply following the movement of the viewpoint A, the appearance of the virtual image V may change instantaneously as described above, which may cause a visual discomfort to the driver. Conditions are set, and if the conditions are met, control is performed to intentionally slow down (suppress) the sensitivity of the warping process.

The control is roughly classified into four methods. The first control is that when the peripheral viewpoint detection unit 186 detects that the viewpoint A is located in the peripheral region of the eyebox EB, even if the viewpoint A moves thereafter, it is ignored and the warping parameter is set. It is a control that keeps the current warping parameters without updating.

The second control temporarily stores the partial area information sent from the viewpoint position detection unit 120 in the temporary storage unit 188 of the partial area information of the eye box, counts a predetermined time by the timer 190, and determines the predetermined time. When the time has elapsed, the partial area information is read out, the ROM 210 is accessed, and the warping parameter is updated (the first process of delaying the warping), or in addition to the process, the viewpoint is obtained after a predetermined time has elapsed. For example, the warping management unit 185 determines whether A stays in the same partial area, and only when it stays, a process of permitting the update of the warping parameter (the second is added to determine whether the viewpoint is in the same area). Processing).

The third control discontinuously detects the viewpoint position and intermittently detects the viewpoint position. For example, using a coarse-dense division type eyebox in which the center is densely divided and the periphery is coarsely divided as shown in FIGS. 7 (A), 7 (B), and 8 (A), in particular, the eyebox is used. It is possible to reduce the detection sensitivity (detection resolution) of the viewpoint A in the peripheral region of the above.

In the fourth control, as shown in FIGS. 9 and 7 (A) to 8 (B), the mode of dividing the eye box is changed according to the speed of the own vehicle (vehicle 1), and the viewpoint is changed. This is a control that adaptively changes the detection sensitivity (detection resolution) of A.

Hereinafter, the description will be given step by step. See FIG. FIG. 5 (A) is a diagram showing an example of viewpoint movement in an eyebox whose interior is divided into a plurality of partial regions, and FIG. 5 (B) is a diagram showing warping parameters for each viewpoint movement shown in FIG. 5 (A). It is a figure which shows the example of the presence or absence of an update in a tabular form.

The example of FIG. 5 is an example of carrying out the first control described above. In the example of FIG. 5A, the eyebox EB shown in FIG. 2B is used (however, it is an example, and the coarse / dense division type eyebox shown in FIG. 7 or the like is used. Is also possible).

In FIG. 5A, each viewpoint movement of (i) to (v) is exemplified as a movement mode of the viewpoint A in the eyebox EB. Further, during driving, the driver's viewpoint A may deviate from the eyebox EB and the detection of the position may be interrupted (viewpoint loss or viewpoint lost), and then the viewpoint A may return to the eyebox EB. As the mode of viewpoint movement in this case, the movements of (1) and (2) and the movements of (3) and (2) are exemplified.

As shown in FIG. 5B, when the viewpoint A moves within the central region ZA (in the case of the viewpoint movements (i) to (iii)), updating the warping parameters is effective, while the viewpoint Regarding the viewpoint movement that occurs when A is in the peripheral region ZB, the update of the warping parameter is invalidated in consideration of the fact that warping has a large effect on the appearance (appearance) of the virtual image V.

Also, in the case of lost viewpoint (in the case of viewpoint movement (1) and (2), (3) and (2)), if warping is forcibly performed, the change in the appearance of the virtual image V may become large and a sense of discomfort may occur. As a general rule, updating the warping parameter is invalid because it is considered to be highly probable. However, if the conditions are set in detail and the predetermined conditions are satisfied, warping may be performed. Such deformations and applications can be made as appropriate.

Next, refer to FIG. FIG. 6 is a timing chart showing an example of control for blunting the reflection of warping parameters on an image. FIG. 6 shows an example of carrying out the second control described above.

As shown in FIG. 6, the detection timing of the viewpoint position arrives periodically at each time point t1 to t5. When the position of the viewpoint A is detected and the detection information is taken into the display control unit 180, Z (p, q) and Z (p) are used as the partial regions where the viewpoint A exists at each time point t1 to t5. , Q), Z (r, s), Z (u, v), Z (u, v) are detected.

When the above-mentioned first process (process of delaying the update of the warping parameter by a predetermined time and suppressing the instantaneous warping following the movement of the viewpoint) is performed, the movement of the viewpoint A is detected and then the predetermined time is reached. Warping is performed when τ has elapsed. By delaying the reflection of the new warping parameter on the image by a predetermined time, it is possible to prevent the image (virtual image) from changing instantaneously following the viewpoint A and reduce the sense of discomfort.

Further, when the second process (furthermore, the process of determining whether the viewpoint A remains in the same partial region even after the elapse of the predetermined time) is performed, each of the time when the partial region is detected and after the elapse of the predetermined time τ. It is determined whether or not the partial regions where the viewpoint A at the time point is located match. If they match, warping is performed (in other words, the warping parameters are updated), and if they do not match, warping is not performed (in other words, the warping parameters are not updated).

For example, it can be assumed that the driver's viewpoint A moves instantaneously over a fairly wide range for some reason while driving the vehicle 1. Even in such a case, if the second process is performed, the viewpoint can be seen. When A is moving, the warping parameters are not updated, and when it is detected that the movement is completed and the position of the viewpoint is stable, the image can be corrected by the updated warping parameters. , It is suppressed that the appearance of the image (virtual image) changes one after another and a sense of discomfort occurs.

In the example of FIG. 6, the warping parameter corresponding to the partial region Z (p, q) is valid during the period t2 to t5, and the warping parameter corresponding to the partial region Z (u, v) is valid after the time t5. It becomes valid.

Further, the above-mentioned first and second processes may be performed only when the viewpoint moves when the viewpoint A is in the peripheral region of the eyebox EB (third process). When the viewpoint is in the peripheral area, which is considered to have a large change in the appearance of the image (virtual image) due to the update of the warping parameter, the third process is performed to instantly change the appearance of the image (virtual image) one after another. It is possible to suppress the change to.

Next, reference to FIGS. 7 and 8. 7 (A) and 7 (B) are diagrams showing a configuration example of a coarse-dense division type eye box. FIG. 8A is a diagram showing another configuration example of the coarse / dense division type eyebox, and FIG. 8B is a diagram showing a configuration example of the eyebox in which the dense portion region is increased to the upper limit.

The above-mentioned third control is realized by intermittently (not continuously) detecting the viewpoint position. For example, when the viewpoint A is within a predetermined range of the eye box, when the viewpoint A is moved from the current position by a predetermined distance in a predetermined direction (for example, the X-axis direction), the viewpoint A is moved to another position different from the current position. The warping parameter is deemed to be updated to the warping parameter corresponding to another position, but on the other hand, when the viewpoint A is within a predetermined other range, the viewpoint A is in a predetermined direction (for example, from the other position described above). Even if the viewpoint A moves to a different position from the other position by moving a predetermined distance in the X-axis direction in the same manner as above, the warping parameter corresponding to the other position is not updated. This control is realized by the display control unit 180 (warping control unit 184 of the display control unit 180).

In other words, when the viewpoint A repeatedly moves in a predetermined direction by a predetermined distance, the warping parameter is updated for each movement in a certain section, for example, regardless of the division method inside the eyebox EB. However, when the viewpoint moves further to a different section, the warping parameter is not updated for each movement, so that the warping parameter is updated continuously, with, without, or with. Not, in other words, intermittent updates are carried out. As a result, the sensitivity of the warping correction process (which can also be called the sensitivity of viewpoint detection) can be lowered, and the occurrence of discomfort due to the change in the appearance of the image (virtual image) due to the update of the warping parameter can be suppressed. ..

Further, for example, as the eye box, as shown in FIGS. 7 and 8, a coarse-dense division type eye box in which the central portion (central portion) is densely divided and the peripheral portion (peripheral portion) is roughly divided is adopted. The position of the viewpoint A may be determined in units of partial regions, and viewpoint tracking warping control may be performed. In terms of determining the viewpoint position in units of the partial area of the eyebox EB, it is common to both the center and the periphery of the eyebox, but in the periphery, the area of one partial area is large, so even if the viewpoint moves a little, It is less likely that the line of sight will shift to the next adjacent subregion. Therefore, the frequency of detecting the movement of the viewpoint is reduced, and the frequency of updating the warping parameter is suppressed accordingly.

In the example of FIG. 7A, in the eye box EB, the inside of the outline C of the quadrangle of the thick line is the central region ZA, and the outer region thereof is the peripheral region ZB. As shown in the figure, in the central region ZA, the region is divided more densely (more finely) and the detection sensitivity of the viewpoint position is high, while in the peripheral region ZB, the division of the region is roughened and the viewpoint position is divided. The detection sensitivity of is reduced as compared with the central region ZA.

In FIG. 7B, another quadrangular contour D is provided outside the quadrangular contour C of the thick line, and the region sandwiched between the contour C and the contour D is designated as the first peripheral region ZC. The region outside the peripheral region ZC of 1 is designated as the second peripheral region ZB'. It is common with the example of FIG. 7A in that the detection sensitivity of the viewpoint position is suppressed in the peripheral region, but in the case of FIG. 7B, the number of partial regions inside the eyebox EB is further increased. There is. Therefore, FIG. 7 (B) has improved detection sensitivity of the viewpoint position as compared with FIG. 7 (A). Specifically, the peripheral region ZB is divided into the first and second peripheral regions ZC and ZB', and the division of the partial region in the first peripheral region ZC is made finer to increase the number of partial regions. Therefore, the detection sensitivity of the viewpoint position in the peripheral region ZB (the region shaded) is improved as compared with the example of FIG. 7 (A).

In the example of FIG. 7B, it can be considered that the central region ZA, which has high sensitivity for viewpoint detection, is virtually expanded to the range of the contour (contour line) D of the quadrangle.

Further, in the example of FIG. 8A, the inside of the contour D of the quadrangle is all finely divided, and therefore, a denser partial region is formed also in FIG. 7B. In the case of FIG. 8A, it can be considered that the central region ZA in the eyebox EB (see, for example, FIG. 7A) has expanded to a part of the peripheral region thereof.

Further, in the example of FIG. 8B, the entire eye box is finely divided, and the viewpoint position detection sensitivity of the entire eye box is maximized. In the case of FIG. 8A, it can be considered that the central region ZA in the eyebox EB (see, for example, FIG. 7A) has expanded to the entire range of the peripheral region.

The first to third controls described above may be performed when the vehicle 1 is in a low speed state including a stopped state. In other words, when the speed detection unit 182 (which also functions as a low speed state determination unit) in FIG. 4 determines that the speed of the vehicle 1 is in a low speed state, the control unit (display control unit 180 or warping control unit 180) 184) may implement at least one of the first control, the second control, and the third control.

When the vehicle 1 is in a low speed state, the driver is sensitive to visual fluctuations such as in front and can easily detect the fluctuations. Therefore, at this time, by performing the above control, it is possible to reduce the sensitivity of updating the warping parameter and suppress the occurrence of a sense of discomfort due to a change in the appearance of the image (virtual image).

Next, refer to FIG. FIG. 9 is a diagram showing an example of characteristics in control for changing the viewpoint detection sensitivity (viewpoint detection resolution) of the eyebox according to the vehicle speed.

In the example of FIG. 9, in the range where the speed (vehicle speed) of the vehicle 1 is U1 to U2, a process of changing the detection sensitivity of the viewpoint position of the eye box is performed in correspondence with the vehicle speed. The eyebox EB is divided into a plurality of partial regions at the initial stage when the head-up display device is in the operating state, and in this state, the detection sensitivity of the viewpoint position in the eyebox EB is N1.

The control unit (display control unit 180 or warping control unit 184 in FIG. 4) determines the position of the viewpoint in units of each partial region of the eyebox EB, and corresponds to the increase in the speed of the vehicle 1. By increasing the number of subregions in the entire eyebox, the resolution for detecting the viewpoint position is improved. At the vehicle speed U2, the viewpoint position detection sensitivity in the eyebox EB has increased to N2.

Further, in the example of FIG. 9, when increasing the number of the partial regions of the eyebox EB as the vehicle speed increases, the range of the dense partial regions from the center to the periphery of the eyebox EB increases as the speed of the vehicle 1 increases. Implement control to spread. In other words, control is performed to reduce the range in which the sensitivity of updating the warping parameter is suppressed.

As the speed of the vehicle 1 increases, it becomes difficult for the driver to recognize the discomfort. Therefore, the area for taking measures against the discomfort is reduced as the speed increases. The detection sensitivity of the viewpoint position in the peripheral region of the eyebox EB increases as the vehicle speed increases. This makes it possible to correct the distortion of the display due to a small movement of the viewpoint by the warping process and perform the display process with more emphasis on the visual sense.

Further, in the example of FIG. 9, in the control unit (display control unit 180 or warping control unit 184), the speed of the vehicle 1 is equal to or higher than the first speed value U1 (U1> 0) and the second speed. When the speed is within the range of the second speed value U2 or less, which is larger than the value, the control for improving the detection resolution of the viewpoint position corresponding to the increase in the speed of the vehicle 1 is performed, and the speed of the vehicle 1 is increased. When it is less than the first velocity value U1 (the range of the characteristic line Q1 of FIG. 9) and when it is larger than the second velocity value U2 (the range of the characteristic line Q4 of FIG. 9), the resolution of detecting the viewpoint position is determined. Keep it constant.

In the seventh aspect, the resolution of detecting the viewpoint position corresponding to the increase in the vehicle speed is improved in the predetermined range of the vehicle speed (the range in which U1 ≦ U ≦ U2 is satisfied for the vehicle speed U). Implement control. Further, if the above control is to be applied even when the vehicle speed is smaller than U1 and larger than U2, the burden on the HUD device (control unit) becomes heavy, so the control is not performed within that range. Care is taken not to put an unreasonable burden on the device.

Further, as a mode of increasing the number of the partial regions of the eyebox EB as the vehicle speed increases, there are two modes shown by the characteristic lines Q1 and Q2 in FIG.

One of them is that when the control for improving the detection resolution (detection sensitivity) of the viewpoint position corresponding to the increase in the speed of the vehicle 1 is performed, the resolution is high in the range where the vehicle speed is close to the first speed value U1. This is a control (control indicated by the characteristic line Q2) in which the degree of improvement is moderated and the degree of improvement in resolution becomes steeper as the distance from the first speed value U1 increases.

The other is a control in which the degree of improvement in resolution is moderated in the range where the vehicle speed is close to the first speed value U1, and the degree of improvement in resolution becomes steeper as the vehicle speed moves away from the first speed value U1. This is a control (control indicated by a characteristic line Q3 having a substantially S-shaped shape) in which the degree of improvement in resolution is moderated as the vehicle speed approaches the second speed value U2.

In other words, it is a low-speed state in which the driver can easily perceive a visual change in the image (virtual image) when improving the resolution (detection sensitivity) of detecting the viewpoint position in the eyebox EB according to the increase in vehicle speed. (In other words, when the vehicle speed is in the range close to the first speed value U1), the degree of increase in the detection resolution (detection sensitivity) is moderated so as to suppress the sudden update of the warping parameter. Control (control of the characteristic line Q2) is performed, or in addition to the control, control is performed to moderate the degree of increase in the detection resolution (detection sensitivity) as the second velocity value U2 is approached. By implementing this, when the second speed value U2 is reached, the detection resolution (detection sensitivity) is saturated and becomes constant, so that the change suddenly (suddenly) peaks out and suppresses the occurrence of discomfort. Control (control indicated by characteristic line Q3) is performed. With these controls, the visibility of the virtual image can be further improved.

Next, refer to FIG. FIG. 10 is a flowchart showing a procedure example of the first warping image correction control (first control shown in FIG. 5).

The position of the viewpoint is monitored (step S1), and the presence or absence of movement of the viewpoint is detected (step S2). In step S2, when N (none), the process returns to step S1, and when Y (yes), it is determined whether or not the viewpoint position has been rediscovered after the viewpoint is lost (step S3).

If it is Y in step S3, the process proceeds to step S4, the viewpoint movement is ignored, and the current warping parameter is maintained. If it is N in step S3, the process proceeds to step S5, and it is detected whether or not the position of the viewpoint before movement is located in the peripheral region of the eye box.

If it is Y in step S5, the process proceeds to step S4, the viewpoint movement is ignored, and the current warping parameter is maintained. If it is N in step S5, the process proceeds to step S6, and image correction is performed using the warping parameter corresponding to the viewpoint position after movement. In step S7, it is determined whether or not to end the image correction. If it is Y, it ends, and if it is N, the process returns to step S1.

Next, refer to FIG. FIG. 11 is a flowchart showing a procedure example of the second warping image correction control (second control shown in FIG. 6). In addition, here, a procedure example is shown for the second control including the process of determining whether or not the viewpoint stays in the same region after the lapse of a predetermined time.

The position of the viewpoint is monitored (step S10), and the presence or absence of movement of the viewpoint is detected (step 11). In step 11, when N (none), the process returns to step S10, and when Y (yes), the information on the viewpoint position after movement is acquired (step S12).

Subsequently, the information on the viewpoint position after the elapse of the predetermined time τ is acquired (step S13). Next, it is determined whether or not the area where the viewpoint was located before the movement and the area after the movement are matched (step S14). In step S14, if it is Y, the process proceeds to step S15, and image correction is performed using the warping parameters corresponding to the viewpoint position after movement (partial area of the eyebox after movement) (step S15). .. When N in step S14, the process proceeds to step S16, the viewpoint movement is ignored, and the current warping parameter is maintained. In step S17, it is determined whether or not to end the image correction, and if it is Y, it ends, and if it is N, the process returns to step S10.

Next, refer to FIG. FIG. 12 is a flowchart showing a procedure example of the third warping image correction control (third control shown in FIGS. 7 and 8). Here, an example of a procedure when using a coarse / dense division type eyebox is shown.

First, a coarse-dense division type eyebox (intermittent division type eyebox) in which the center is densely divided and the periphery is roughly divided is set (step S20). Subsequently, the viewpoint position is monitored (step S21), and then the presence or absence of viewpoint movement is determined (step S22).

If Y is present in step S22, the process proceeds to step S23, and image correction is performed using the warping parameter corresponding to the viewpoint position after movement. If N in step S22, the process returns to step S21. In step S24, it is determined whether or not to end the image correction, and if it is Y, it ends, and if it is N, the process returns to step S21.

Next, refer to FIG. FIG. 13 is a flowchart showing a procedure example of the fourth warping image correction control (fourth control shown in FIG. 9).

The vehicle speed is detected (step S20), and then the number and shape of the partial regions in the eyebox are adaptively changed according to the vehicle speed (step S31). Specifically, the internal structure of the eye box is appropriately changed according to the characteristic lines Q1, Q2 or Q3, Q4 in FIG. Next, the viewpoint position is monitored (step S32), and then the presence or absence of viewpoint movement is determined (step S33).

In step S33, when N, the process returns to step S32, and when Y, the process proceeds to step S34, and image correction is performed using the warping parameters corresponding to the viewpoint position after movement. Next, it is determined in step S35 whether or not to end the image correction, and if it is Y, it ends, and if it is N, the process returns to step S30.

Next, refer to FIG. FIG. 14 (A) is a diagram showing a display example by the road surface superimposition HUD, FIG. 14 (B) is a diagram showing a display example by the inclined surface HUD, and FIG. 14 (C) is a configuration example of a main part of the HUD device. It is a figure which shows.

14 (A) corresponds to the image display surface (reference numeral 117 of FIG. 4 or reference numeral 163 of FIG. 14 (C)) of the display unit (reference numeral 116 of FIG. 4 or reference numeral 161 of FIG. 14 (C)). An example of virtual image display by a road surface superimposing HUD in which a virtual virtual image display surface PS is arranged so as to overlap the road surface 41 in front of the vehicle 1 is shown.

In FIG. 14B, the distance between the near end portion of the virtual image display surface PS on the side closer to the vehicle 1 and the road surface 41 is small, and the distance between the far end portion and the road surface 41 on the far side from the vehicle 1 is small. An example of displaying a virtual image by an inclined surface HUD is shown in which the virtual image display surface PS is arranged at an angle with respect to the road surface 41 so that the distance from the virtual image display surface PS becomes large.

These are various, for example, in the range of 5 m to 100 m in front of the vehicle 1 by using the wide virtual image display surface PS superimposed on the road surface 41 or the wide virtual image display surface PS provided at an angle with respect to the road surface 41. It is possible to display, the HUD device is enlarged, the eyebox EB is also enlarged, the viewpoint position is detected with high accuracy in a wider range than before, and image correction using appropriate warping parameters is performed. It is preferable to do so. In this case, for example, when the viewpoint A is in the vicinity of the eyebox EB, the visibility of the image (virtual image V) may decrease due to frequent updates of the warping parameters. Therefore, the control method of the present invention may occur. The application of is valid.

Next, refer to FIG. 14 (C). The HUD device 107 of FIG. 14C is designed with a control unit 171, a light projecting unit 151, a screen 161 as a display unit having an image display surface 163, a reflector 133, and a reflective surface as a free curved surface. It has a curved mirror (concave mirror or the like) 131, and an actuator 173 that drives the display unit 161.

In the example of FIG. 14C, the HUD device 107 is a curved surface that is an optical member that projects display light onto the windshield 2 when adjusting the position of the eyebox EB according to the height position of the driver's viewpoint A. This is handled by changing the reflection position of the image display light 51 on the optical member 131 without moving the mirror 131 (the actuator for the curved mirror 131 is not provided).

In other words, when adjusting the height position of the eyebox EB according to the height position of the driver's eyes (viewpoint A), the optical member 131 that projects light onto the projected member 2 is, for example, using an actuator. This is done by changing the light reflection position on the optical member 131 without rotating it. The height direction is the Y direction in the drawing (the direction along the perpendicular line of the road surface 41, and the direction away from the road surface 41 is the positive direction). The X direction is the left-right direction of the vehicle 1, and the Z direction is the front-rear direction (or the front direction) of the vehicle 1.

Recent HUD devices tend to be developed on the premise of displaying a virtual image over a fairly wide area in front of the vehicle, for example, and in this case, the device is inevitably enlarged. Naturally, the optical member 131 is also increased in size. When the optical member 131 is rotated or the like by using an actuator or the like, the accuracy of controlling the height position of the eyebox EB may be lowered due to the error, and in order to prevent this, the light beam is emitted from the optical member 131. It was decided to deal with this by changing the position of reflection on the reflective surface of.

In such a large optical member 131, the distortion of the virtual image is prevented from becoming apparent as much as possible by optimally designing the reflecting surface as a free curved surface, but as described above, for example, in the eye box EB. When the driver's viewpoint A is located in the vicinity, distortion may inevitably become apparent. Therefore, in such a case, by performing control such as lowering the sensitivity of updating the warping parameter, it is possible to prevent a sense of discomfort due to a change in appearance due to distortion of the virtual image V, and the above control. Can be effectively utilized to improve the visibility of the virtual image V.

As described above, according to the present invention, when the viewpoint position tracking warping control for updating the warping parameter according to the viewpoint position of the driver is performed, the appearance of the image is instantaneously changed as the warping parameter is updated. It is possible to effectively suppress the change that causes the driver to feel uncomfortable.

The present invention can be used in both a monocular type HUD device in which the display light of the same image is incident on each of the left and right eyes, and a parallax type HUD device in which an image having parallax is incident on each of the left and right eyes.

In the present specification, the term vehicle can be broadly interpreted as a vehicle. In addition, terms related to navigation (for example, signs, etc.) shall be interpreted in a broad sense in consideration of, for example, the viewpoint of navigation information in a broad sense useful for vehicle operation. Further, the HUD device shall include one used as a simulator (for example, an aircraft simulator).

The present invention is not limited to the above-mentioned exemplary embodiments, and those skilled in the art will be able to easily modify the above-mentioned exemplary embodiments to the extent included in the claims. ..

1 ... Vehicle (own vehicle), 2 ... Projected member (reflected translucent member, windshield, etc.), 4 ... Projected area, 5 ... Virtual image display area, 7 ... Steering wheel, 51 ... Display light, 100 ... HUD device, 110 ... Viewpoint detection camera 110, 112 ... Light source, 114 ... Floodlight, 116 ... Display, 117 ... Display surface (Image display surface), 118 ... Projection optical system, 120 ... Viewpoint position detection unit (viewpoint position determination unit), 122 ... Viewpoint coordinate detection unit, 124 ... Partial area detection unit in eyebox , 130 ... Operation unit, 131 ... Curved mirror (concave mirror, etc.) 133 ... Reflector (including reflection mirror, correction mirror, etc.), 140 ... Vehicle ECU, 150 ... Bus, 151 ... Light source unit, 161 ... Display unit (screen, etc.), 63 ... Display surface (image display surface), 170 ... Bus interface, 171 ... Control unit, 173 ... Display unit Driving actuator, 180 ... Display control unit, 182 ... Speed detection unit, 184 ... Warping control unit, 185 ... Warping management unit, 186 ... Peripheral viewpoint detection unit, 188 ... Eye Temporary storage unit for partial area information of the box, 200 ... image generation unit, 210 ... ROM, 220 ... VRAM, 212 ... image conversion table, 222 ... image (original image) data, 224 ... Image data after warping processing, EB ... Eye box, Z (Z1 to Z9, etc.) ... Partial area of eye box, WP ... Warping parameter, PS ... Virtual image display surface, V.・ ・ Virtual image, ZA ・ ・ ・ Central part of eye box (central area, main area). ZB: Peripheral part of eye box (peripheral area, peripheral area).

Claims (10)

A head-up display (HUD) device that is mounted on a vehicle and projects an image onto a projected member provided on the vehicle so that the driver can visually recognize a virtual image of the image.
An image generator that generates the image and
A display unit that displays the image and
An optical system including an optical member that reflects the display light of the image and projects it onto the projected member.
The warping parameter is updated according to the viewpoint position of the driver in the eye box, and the image displayed on the display unit using the warping parameter is pre-distorted so as to have a characteristic opposite to the distortion characteristic of the virtual image of the image. A control unit that performs warping control following the viewpoint position
Have,
The control unit
When at least one of the driver's left and right viewpoints is located in a predetermined area, the first control that maintains the warping parameter before the movement without updating even if the viewpoint moves.
as well as,
A second control that slows down the reflection of the warping parameter on the image displayed on the display unit with respect to the viewpoint position input.
as well as,
A third control that intermittently updates the warping parameter with respect to the movement of the driver's viewpoint.
A head-up display device comprising performing at least one of the above. The control unit receives the first control when performing the first control.
The feature is that the inside of the eye box is divided into a central region and a peripheral region, and the warping parameter is maintained without being updated even if the viewpoint moves when the viewpoint is located in the peripheral region. The head-up display device according to claim 1. The control unit receives the second control when performing the second control.
When the viewpoint moves from the first position to the second position, the warping parameter is reflected on the image displayed on the display unit for a predetermined time from the time when the movement to the second position is detected. Perform the first process to delay,
Or
When the first process is performed and the predetermined time elapses and the viewpoint remains at the second position, the warping parameter corresponding to the second position is displayed. Perform the second process to reflect in the image,
Or
The inside of the eye box is divided into a central region and a peripheral region, and the first process or the second process is performed only when the viewpoint is in the peripheral region.
The head-up display device according to claim 1. The control unit receives the third control when performing the third control.
When the viewpoint moves in a predetermined direction from the current position by a predetermined distance, it is considered that the viewpoint has moved to another position different from the current position, and the warping parameter is updated to the warping parameter corresponding to the other position. But,
Even if the viewpoint moves from the other position in the predetermined direction by the predetermined distance and the viewpoint moves to another position different from the other position, the update to the warping parameter corresponding to the other position is performed. Do not carry out
Or
As the eye box, an eye box of a coarse / dense division method in which the center is densely divided and the periphery is roughly divided is adopted, the position of the viewpoint is determined in units of each partial region, and the viewpoint tracking warping control is performed. ,
The head-up display device according to claim 1, wherein the head-up display device is characterized in that. Further, it has a low-speed state determination unit for determining whether or not the speed of the vehicle is a low-speed state.
The control unit is characterized in that when the vehicle is in the low speed state including a stopped state, at least one of the first control, the second control, and the third control is performed. The head-up display device according to any one of claims 1 to 4. The eye box is divided into a plurality of partial regions at the initial stage when the head-up display device is in an operating state.
The control unit
The position of the viewpoint is determined using each partial region of the eye box as a unit, and the position of the viewpoint is determined.
By increasing the number of the partial regions in the entire eye box in response to the increase in the speed of the vehicle, the resolution of detecting the viewpoint position is improved, and in increasing the number of the partial regions, the said As the speed of the vehicle increases, the range of the dense subregion extends from the center to the periphery of the eyebox.
The head-up display device according to any one of claims 1 to 4. When the speed of the vehicle is within the range of the first speed value U1 (U1> 0) or more and the second speed value U2 or less, which is larger than the second speed value, the control unit is used. When the speed of the vehicle is less than the first speed value, and when the speed of the vehicle is less than the first speed value, the control for improving the detection resolution of the viewpoint position corresponding to the increase in the speed of the vehicle is performed. The head-up display device according to claim 6, wherein when the value is larger than the value, the resolution of detecting the viewpoint position is kept constant. In carrying out the control for improving the resolution of the detection of the viewpoint position corresponding to the increase in the speed of the vehicle.
In the range where the vehicle speed is close to the first speed value, the degree of improvement in resolution is moderated, and as the vehicle speed moves away from the first speed value, the degree of improvement in resolution is steepened.
Or
In the range where the vehicle speed is close to the first speed value, the degree of improvement in resolution is moderated, and as the distance from the first speed value increases, the degree of improvement in resolution is controlled to be steeper, and the vehicle speed is controlled. Controls to slow down the degree of improvement in the resolution as the speed approaches the second speed value.
The head-up display device according to claim 7, wherein the head-up display device is characterized in that. The head-up display device is
When adjusting the position of the eye box according to the height position of the viewpoint of the driver, the optical member is not moved, and the reflection position of the display light of the image on the optical member is changed. The head-up display device according to any one of claims 1 to 8. A virtual virtual image display surface corresponding to the image display surface of the display unit is arranged so as to overlap the road surface in front of the vehicle.
Or
The distance between the near end portion of the virtual image display surface on the side closer to the vehicle and the road surface is small, and the distance between the far end portion on the far side from the vehicle and the road surface is large. Is arranged at an angle to the road surface.
The head-up display device according to any one of claims 1 to 9.

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