DE102015007485A1 - Method and device for adapting image contents of a head-up display on a windshield of a vehicle - Google Patents

Abstract

The invention relates to a method for adapting image contents of a head-up display on a windshield of a vehicle, in which a perception condition of the image contents is evaluated, as a function of which optimal visibility of the image content is set. In a method in which the optimum visibility is realized with particularly simple means, the existence of sunglasses (19) is detected as a perceptual condition in front of a viewer (13) of the image contents, and in the presence of sunglasses (19) the optimum visibility is achieved a change in contrast and / or brightness and / or the color of the image content is set.

Description

The invention relates to a method for adapting image contents of a head-up display on a windshield of a vehicle, in which a perception condition of the image contents is evaluated, as a function of which optimal visibility of the image content is set.

From the DE 695 03 955 C2 For example, a head-up display for a vehicle is known, which has an image projection device that outputs a visible light beam, which is reflected by the windshield. In addition, there is an optical sensor which includes a signal in response to the ambient light level near the displayed image and a brightness control knob. The brightness control knob generates a signal to a control unit to change the contrast or brightness of the display image. The brightness control can also be automatically changed in response to the ambient light conditions determined by the sensor and thus always ensures optimum visibility of the image.

The reflection of the radiation beam emitted by the head-up display on the windshield results in a partial polarization of the light. If the driver uses a pair of sunglasses with orthogonal polarization when driving, the beams reflected and partially polarized by the windshield are more or less attenuated by the polarization plane of the lenses oriented perpendicular thereto, whereby the driver only very limited the displayed image content of the head-up display or not at all.

The object of the invention is to provide a method and a device in which the driver can always perceive a reliable visibility of the image content of the head-up display even when occurring polarization effects.

The invention results from the features of the independent claims. Advantageous developments and refinements are the subject of the dependent claims. Other features, applications and advantages of the invention will become apparent from the following description, as well as the explanation of embodiments of the invention, which are illustrated in the figures.

The object is achieved with a method in that the perception condition of an existence of sunglasses in front of a viewer of the image content is detected and in the presence of sunglasses optimal visibility by changing a contrast and / or brightness and / or the color of the image content is set. This has the advantage that whenever a partially polarized beam of the head-up display is viewed by an orthogonal polarized driver's sunglasses, an automatic adjustment of the contrast and / or the brightness of the image content coming from the head-up display is achieved is achieved. If the sunglasses are not detected, the parameters of the head-up display are reset to the initial state or this is retained.

In one embodiment, the contrast and / or the brightness of the image content are increased after detection of the sunglasses by a predetermined amount, which corresponds to the value that has occurred by a polarization attenuation of the sunglasses. This amount can for example be firmly anchored in the system, but also be parameterizable by the user. Furthermore, the color saturation of the displayed contents and / or the coloration itself can also be varied in order to ensure optimum perception by the driver.

Advantageously, an image recognition method is used to determine the existence of sunglasses. Such image recognition methods are well known and thus provide a cost-saving means for detecting the sunglasses.

In one embodiment, in the image recognition method, contrast ratios within a recognized face of the viewer of the image contents are evaluated. Alternatively, however, there is also the possibility that in the image recognition method, a feature based on edge detection feature extraction is used, whereby a reliable detection of the sunglasses is guaranteed.

In one embodiment, correlating reflection patterns of both eyeglass lenses of the sunglasses are evaluated to determine the sunglasses. The evaluation of these correlating reflection patterns is a particularly simple optical method to draw conclusions about the presence of sunglasses.

In a variant, an auxiliary light beam is emitted, which is reflected by the lenses, wherein a surface-related reflectance of the auxiliary light beam is determined and is closed depending on the surface reflectance on the presence of the sunglasses. The auxiliary light beam can be designed in particular as an infrared beam, so that it is not visible to the driver and does not draw any distraction during the driving process.

In a particularly simple embodiment, an optically effective target arranged on at least one spectacle lens is scanned to identify the sunglasses.

• – das Head-up-Display mit einer Bildquelle zur Aussendung eines sichtbaren Lichtstrahles und einer optischen Einheit zur Umlenkung des sichtbaren Lichtstrahles auf die Windschutzscheibe,
• – eine Fahrerbeobachtungseinrichtung zur Erzeugung eines Bildes des Fahrers, die im oberen Bereich der Fahrzeugscheibe angeordnet ist,
• – eine Bildauswerteeinheit zur Detektion einer Sonnenbrille des Fahrers aus dem von der Fahrerbeobachtungseinrichtung bereitgestellten Bild und zur Aussendung eines elektrischen Signales an das Head-up-Display zur Veränderung des Kontrastes und/oder der Helligkeit und/oder einer Farbe des Bildinhaltes bei Vorhandensein einer Sonnenbrille.

A development of the invention relates to a device for adapting image contents of a head-up display on a windscreen of a vehicle, comprising

• - The head-up display with an image source for emitting a visible light beam and an optical unit for deflecting the visible light beam on the windshield,
• A driver observation device for generating an image of the driver, which is arranged in the upper region of the vehicle window,
• An image evaluation unit for detecting a driver's sunglasses from the image provided by the driver observation device and emitting an electrical signal to the head-up display to change the contrast and / or the brightness and / or a color of the image content in the presence of sunglasses.

This has the advantage that, with a very simple system, adjustment of the image contents output by the beam of the head-up display can be made depending on whether the driver is wearing sunglasses or not.

In a particularly favorable embodiment, the image observation device is designed as a camera.

Further advantages, features and details will become apparent from the following description in which - where appropriate, with reference to the drawings - at least one embodiment is described in detail. Described and / or illustrated features may form the subject of the invention itself or in any meaningful combination, optionally also independent of the claims, and in particular may also be the subject of one or more separate application / s. The same, similar and / or functionally identical parts are provided with the same reference numerals.

Show it:

1 an embodiment of an inventive device,

2 an embodiment for changing the position of a pair of sunglasses while driving the vehicle,

3 a representation for the compensation of the tilt-dependent polarization attenuation by increasing the brightness of the illumination source of the head-up display.

In 1 is a section of a vehicle 1 shown, which is a windshield 3 includes. In the vehicle interior of the vehicle 1 is arranged a head-up display, which is a, an optically visible beam emitting image source 5 having. The optically visible beam is thereby from a first mirror 7 and a concave mirror 9 , which is referred to as a secondary mirror, on the windshield 3 diverted. It is created in the windshield 3 a virtual picture 11 which from the driver 13 is perceived.

In the upper part of the windshield 3 is an image capture camera 15 arranged with an image evaluation unit 17 connected, which in turn leads to the head-up display. Wears the driver while driving a pair of sunglasses 19 as they are in 2 is shown, so are those of the windshield 3 reflected and partially polarized beam of the head-up display through the polarization planes oriented perpendicularly to the lenses of the sunglasses 19 attenuated. This attenuation depends on the tilt angle α of the polarization planes of the sunglasses 19 and the windshield 3 and has a maximum in orthogonality, ie, the imaginary line formed by the tilt angle α passes horizontally through both eyes of the driver. A minimum of damping occurs in parallelism, ie the driver turns his head around the viewing axes, so that the axis called by the driver's eyes 13 is vertical. As a result, the image contents that are emitted by the head-up display are normally not noticeable to the driver and are slightly more visible when the head is tilted.

By means of the image capture camera 15 It is now determined if the driver is wearing sunglasses 19 wears or not, since this capture camera 15 on the driver's head 13 is directed and, ideally, the entire face of the driver 13 overlooked. In the image evaluation unit 17 become the ones of the imaging camera 15 recorded images evaluated. For this purpose, z. B. contrast ratios are evaluated within the detected facial area or based on edge detection feature extraction for the detection of the sunglasses 19 be used. Alternatively, correlating reflection patterns of both spectacle lenses can be evaluated.

In a further embodiment, the system has, for example, a not shown active subsystem for emitting an infrared auxiliary beam to the presence of the sunglasses 19 by determining the area-related reflectance of the emitted auxiliary light beam to detect. Another possibility is that the sunglasses 19 is provided with an infrared target, z. B. in the form of a sticker or other mark, which the optical detection of the sunglasses 19 simplified. Has the image evaluation unit 17 the presence of sunglasses 19 detected, this sends a signal to the head-up display so that this the brightness and / or contrast of the displayed image content and / or the brightness of the image source 5 the head-up display automatically increases by a certain amount. This amount ideally corresponds to the value that resulted from the polarization attenuation of the sunglasses. This amount is preferably firmly anchored in the system. However, it can also be parameterized by the user. Furthermore, the color saturation of the displayed contents and / or the coloration itself can also be varied in order to ensure optimum perception by the driver.

Represents the image evaluation unit 17 fixed that the driver 13 no sunglasses 19 carries more, the parameters of the head-up display are reset to the original state. For this purpose, a stepless or finely resolved as possible discrete tracking the head-up parameters depending on the detected tilting α an imaginary axis through both eyes of the driver (eye plane) relative to the horizontal, which is viewed at 0 °, to the angle-dependent polarization attenuation to compensate ( 2 ).

The tilt α itself can be determined by means of an eye tracing system, while the compensation of the angle-dependent polarization damping z. For example, to fixed values, are taken from a table.

In 3 a diagram is shown showing the tilt-dependent polarization attenuation by increasing the brightness of the image source 5 of the head-up display shows. Thus, with a tilt α of 0 °, the illumination brightness of the image source 5 100%, while with a tilt α of -5 ° and + 5 °, the illumination brightness is 75% and with a tilt α of -10 ° or + 10 °, the illumination brightness of the image source 5 50%.

In a further embodiment, an infrared light beam with defined polarization can be emitted in order, by means of evaluation of intensity and polarization, that of the spectacle lenses of the sunglasses 19 and from the through the sunglasses 19 Concealed facial surface reflected beams to draw conclusions about polarization attenuation and transmittance of the lenses and compensate for them by appropriate tracking of the above head-up parameters such as brightness, contrast and / or color. The corresponding adaptation of the head-up display automatically compensates for the polarization effect.

Although the invention has been further illustrated and explained in detail by way of preferred embodiments, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention. It is therefore clear that a multitude of possible variations exists. It is also to be understood that exemplified embodiments are really only examples that are not to be construed in any way as limiting the scope, applicability, or configuration of the invention. Rather, the foregoing description and description of the figures enable one skilled in the art to practice the exemplary embodiments, and those of skill in the knowledge of the disclosed inventive concept may make various changes, for example as to the function or arrangement of individual elements recited in an exemplary embodiment, without Protection area defined by the claims and their legal equivalents, such as further explanations in the description.

LIST OF REFERENCE NUMBERS

1

vehicle

3

Windshield

5

source

7

mirror

9

concave mirror

11

virtual picture

13

driver

15

Imaging camera

17

image evaluation

19

sunglasses

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 69503955 C2 [0002]

Claims (10)

Method for adapting image contents of a head-up display on a windshield of a vehicle, in which a perception condition of the image contents is evaluated, as a function of which optimal visibility of the image content is set, characterized in that the perception condition is an existence of sunglasses ( 19 ) in front of a viewer ( 13 ) of the image content is detected and in the presence of sunglasses ( 19 ) the optimum visibility is set by a change of a contrast and / or a brightness and / or the color of the image contents. A method according to claim 1, characterized in that the contrast and / or the brightness of the image content after detection of the sunglasses ( 19 ) is increased by a predetermined amount, which corresponds to the value obtained by a polarization damping of the sunglasses ( 19 ) occured. Method according to claim 1 or 2, characterized in that for determining the existence of sunglasses ( 19 ) an image recognition method is used. A method according to claim 3, characterized in that in the image recognition method contrast ratios within a recognized face of the viewer ( 13 ) be evaluated A method according to claim 3 or 4, characterized in that in the image recognition method based on edge detection feature extraction is used. Method according to claim 3, 4 or 5, characterized in that for determining the sunglasses ( 19 ) correlating reflection patterns of both eyeglass lenses of the sunglasses ( 19 ) be evaluated. Method according to at least one of the preceding claims, characterized in that an auxiliary light beam is emitted, which is reflected by the spectacle lenses, a surface-related reflectance of the auxiliary light beam is determined and depending on the surface reflectance on the presence of the sunglasses ( 19 ) is closed. Method according to at least one of the preceding claims, characterized in that for the detection of the sunglasses ( 19 ) is scanned on at least one spectacle lens optically effective target is scanned. Device for adapting image contents of a head-up display on a windshield of a vehicle, comprising - the head-up display with an image source ( 5 ) for emitting a visible light beam and an optical unit ( 7 . 9 ) for deflecting the visible light beam on the windshield ( 3 ), - a driver observation device ( 15 ) for generating an image of the driver at the top of the windshield ( 3 ), - an image evaluation unit ( 17 ) for the detection of sunglasses ( 19 ) of the driver ( 13 ) from the driver's observation unit ( 15 ) and to emit an electrical signal to the head-up display to change the contrast and / or the brightness of the image content upon detection of the presence of sunglasses ( 19 ). Apparatus according to claim 9, characterized in that the image observation device as a camera ( 15 ) is trained.

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