DE102016203266A1 - Method for operating a display device and display device - Google Patents

Abstract

The present invention relates to a method of operating a display device (102) having a display (110) and a controller (112), the method comprising a step of transmitting, a step of receiving and a step of checking, wherein sending a display signal (122) to the display device (102) in the step of transmitting, wherein the display signal (122) includes an image content (114) to be displayed on the display (110) and a desired reference feature (120) to be displayed by the display (110) ), wherein in the step of receiving, a control signal (126) is received from the controller (112), the control signal (126) representing an actual reference feature (124) displayed by the display (110), and in the step of checking Proper functioning of the display device (102) using the reference reference feature (120) and the actual reference feature (124) is checked.

Description

The present invention relates to a method of operating a display device, a control device for operating a display device, and a display device.

For a display, an input signal from the display can be checked to ensure that information displayed on the display corresponds to desired information.

The EP 0 856 792 B1 shows a method for safely displaying an image on a monitor.

Against this background, the present invention provides an improved method of operating a display device, an improved control device for operating a display device, and an improved display device according to the main claims. Advantageous embodiments will become apparent from the dependent claims and the description below.

In a pure signal-technical verification of an input signal of a display device, an error on the Anzeigeeirichtung itself can not be detected.

In the approach presented here, a reference feature is sent to the display device parallel to the information to be displayed on the input signal and represented by the latter. A resulting optical information is detected by a sensor. The resulting control signal maps all possible errors in the signal processing in the display device.

A method is presented for operating a display device which has a display and a control device, the method having the following steps:
Sending a display signal to the display device, the display signal representing an image content to be displayed on the display and a target reference feature to be displayed by the display;
Receiving a control signal from the control device, the control signal representing an actual reference feature displayed by the display; and
Checking an intended function of the display device using the desired reference feature and the actual reference feature.

A control device can be understood to mean an optical sensor which is designed to image optical information in an electrical signal. An indication signal may be an input to the display of the display device. The indication signal may be an electrical signal. A reference reference feature may be an optical feature to be presented by the display. An actual reference feature may be an optical feature actually represented by the display. The control signal may be an electrical signal.

As the target reference feature, a target refresh rate of the display can be sent. As the actual reference feature, an actual image refresh rate of the display detected by the control device can be received. The display may have a controllable refresh rate. The actual frame rate can be mapped in the control signal. By using the refresh rate, the full size display can be used to display the image content.

As the target reference feature, a target optical code to be displayed on the display in addition to the image content may be sent. As the actual reference feature, an actual code detected by the control device on the display can be received, which is optically displayed or output by the display, for example. By comparing the desired code with the actual code as an optical code, the functionality of the display can be comprehensively secured.

As a target code, a pattern to be displayed, for example, on the display of distinguishable surfaces can be sent. The code can be a simple pattern. Thus, the code can be easily recognized or evaluated.

The image content may be sent as being displayed in a visible display area of the display. The target code may be sent as being displayed in a hidden reference area of the display. The code can be hidden. This allows a clear representation of the image content can be achieved without a viewer is irritated by the representation of the code.

It may be a dependent of the image content target reference feature are sent. The code may represent encoded information contained in the image content. This can be done using the control signal comprehensive monitoring.

The image content can be sent in a first wavelength range. The reference feature can be sent in a second wavelength range. The first wavelength range may be at least partially different from the second wavelength range. For example, the image content may be transmitted in the visible wavelength spectrum while the reference feature is being transmitted in the infrared wavelength region.

Furthermore, a control device for driving a display device with a display and a control device is presented, wherein the control device is designed to carry out the method according to the approach presented here in corresponding devices.

A controller may be an electrical device that processes electrical signals, such as sensor signals, and outputs control signals in response thereto. The control unit may have one or more suitable interfaces, which may be formed in hardware and / or software. For example, in a hardware configuration, the interfaces may be part of an integrated circuit in which functions of the device are implemented. The interfaces may also be their own integrated circuits or at least partially consist of discrete components. In a software training, the interfaces may be software modules that are present, for example, on a microcontroller in addition to other software modules.

Furthermore, a display device with a display and a control device is presented, wherein the display is designed to display a predetermined by an indication signal image content and also a predetermined by the display signal reference feature, wherein the control device is adapted to image the displayed reference signal in a control signal.

The control device may comprise at least one photosensitive sensor for imaging the reference feature. The sensor may comprise at least one phototransistor or photodiode. As a result, the optical information of the reference feature can be converted into an electrical signal.

The display may have a visible display area for the image content and a hidden reference area for the reference feature. For example, the hidden reference area may be covered by a frame of the display device.

A computer program product with program code which can be stored on a machine-readable carrier such as a semiconductor memory, a hard disk memory or an optical memory and is used to carry out the method according to one of the embodiments described above if the program is installed on a computer or a device is also of advantage is performed.

Embodiments of the approach presented here are shown in the drawings and explained in more detail in the following description. It shows:

1 a block diagram of a control device for driving a display device according to an embodiment of the present invention;

2 an illustration of a display device according to an embodiment of the present invention;

3 a sectional view of a display device according to an embodiment of the present invention;

the 4 to 6 Representations of reference features on a display device according to an embodiment of the present invention;

the 7 to 12 Illustrations of display devices according to further embodiments of the present invention; and

13 a flowchart of a method for operating a display device according to an embodiment of the present invention.

In the following description of preferred embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and similarly acting, wherein a repeated description of these elements is omitted.

1 shows a block diagram of a controller 100 for driving a display device 102 according to an embodiment of the present invention. The control unit 100 and the display device 102 are in a vehicle 104 arranged. The control unit 100 has a provisioning device 106 and an evaluation device 108 on. The display device has a display 110 and a control device 112 on. The display device 102 Here is a gear indicator for an automatic transmission of the vehicle 104 , On the display 110 the display device 102 a currently selected gear position of the automatic transmission is displayed. The current gear is shown as a picture on the display 110 shown. A picture content 114 The picture here is from a vehicle control unit 116 of the vehicle 104 in an image signal 118 provided.

The control unit 100 reads the picture signal 118 one. In the delivery facility 106 becomes the image content 114 by a reference feature 120 added and as an indication signal 122 to the display device 102 sent. The reference feature 120 can be referred to as a reference reference feature.

In the display device 102 become the image content 114 and the reference feature 120 through the display 110 displayed. This is the reference feature 120 Invisible to a viewer. The control device 112 detects the illustrated reference feature 120 and forms an image 124 of the reference feature 120 in a control signal 126 from. The image 124 can be referred to as an actual reference feature. The control signal 126 is from the controller 100 read.

In the evaluation device 108 become the reference feature 120 and his image 124 compared to each other. If the reference feature 120 and the image 124 are substantially identical or identical or very similar, is a proper function of the display device 102 recognized.

If the reference feature 120 and the image 124 to deviate from each other by more than one tolerance becomes a disturbance of the display device 102 detected and a fault signal 128 discontinued.

In one embodiment, the controller 100 a memory 130 in which different predefined reference features 120 for different predefined image contents 114 are deposited. Thus, a certain image content always has the same reference feature 120 added.

It will be an Automotive Safety Integrity Level (ASIL) enabled display module 102 presented. the display 102 can be used, for example, to display the engaged gear positions on the gear selector switch.

Conventional display displays in a car display only images, text or videos that are read from a memory such as RAM. This does not guarantee that these displayed images, logos or videos are exactly what should be displayed. A "freezing" of the image or an incorrect display can not be detected. For example, can be displayed at a gear selector P, although R is engaged.

With the approach presented here, an ASIL (Automotive Safety Integrity Level) classification of a display device 102 how to achieve a TFT / LCD display.

2 shows a representation of a display device 102 according to an embodiment of the present invention. The display device essentially corresponds to the display device in FIG 1 , the display 110 is arranged under a panel and framed by a dark film, in particular a black film. the display 110 the display device 102 is here in a framed by the film or released from the film, visible field of view 200 and an invisible code area 202 divided. In the field of vision 200 becomes the picture information 114 shown as a raster graphic. The picture information 114 here represents a switching sequence of shift stages of the automatic transmission in the form of letters, the currently selected shift stage in the center of the field of view 200 is arranged and highlighted.

In the code area 202 is the reference feature 120 as optical code 120 shown. The code 120 here has a word width of three bits. A bit becomes thereby by a quadrangular area 204 of the code area 202 represented, which is either translucent or opaque. The control device 112 indicates the reading of the code 120 three photosensitive sensors 206 on, each one of the surfaces 204 assigned. Here is switching stage N by two upper bright surfaces 204 and a dark lower surface 204 (110) coded.

the display 110 has a lighting device 208 on and is backlit during operation by this. The lighting device 208 can be referred to as illumination module with reflector, light guide and diffuser film. In translucent areas of the display 110 the backlight shines through.

In one embodiment, the lighting device 208 different light sources. The light sources 210 . 212 have different frequency spectra. In the process, first light sources emit 210 visible, especially white light, while second light sources 212 invisible light, especially emit infrared light. The light sources 210 . 212 may in particular be light-emitting diodes.

3 shows a sectional view of a display device 102 according to an embodiment of the present invention. The display device 102 essentially corresponds to the display device in 2 , Here is the display 110 also a ground glass 300 , a lens 302 and an imaging element disposed therebetween 304 on. The imaging element 304 is for example a liquid crystal display. The lighting device 208 lights up in the ground glass 300 to the light of the light sources 210 . 212 evenly distributed. The imaging element 304 forms the image content 114 from. The control device 112 is on the side of the lens 302 arranged. The light of the lighting device 208 Penetrates the translucent areas of the imaging element 304 , One part 306 coupled in the lens 302 and is about total reflection within the lens 302 to the photosensitive sensors 206 the control device 112 directed.

In one embodiment, the reference feature is provided by the lighting device 208 provided. In this case, the reference feature is displayed via a pulse sequence of the light provided. The pulse sequence is provided in such a way that a human observer does not perceive the pulse sequence due to the inertia of his eyes. It can be unlike 2 on the hidden area 202 be waived.

The active picture 114 is provided with an invisible to the human eye frame rate, ie greater than 30 frames per second, which is due to the photodiodes 206 is detected and thus the freezing of the image can be detected.

This is between the picture 114 the inserted switch position and a black picture or screen 110 off at a certain frequency back and forth.

Alternatively, the second light sources 212 provide the reference feature in the invisible human infrared spectrum.

When viewing an image 114 with, for example, a shift logic of a gear selector lever on a TFT or LCD display 110 , the light of the displayed display is in the glass substrate 302 of the display 110 totally reflected and thus reaches the outer edges of the display 110 , Here is at an outer edge at least one photodiode or a phototransistor 206 whose signals are read out and evaluated.

In one embodiment, detection is by means of a photodiode 206 with standard white background LEDs 210 , which, however, may be more prone to error due to sunlight or daylight. This can be controlled by adjusting the threshold of the photodiodes 206 for signal detection according to the vehicle ambient light is controlled.

In one embodiment, IR LEDs are 212 between the white background LEDs 210 their light as previously described also to the appropriate IR photodiodes 206 reflected back. This eliminates the vulnerability to daylight.

The 4 to 6 show representations of reference features 120 on a display device 102 according to an embodiment of the present invention. The display device 102 corresponds to the display device in the 2 and 3 ,

This detection takes place in the fixed switching positions (P, R, N, D) and the respective active areas 204 where, for example, a certain logic is deposited, which the photodiodes 206 detect. This can ensure the correct display of a specific switching position.

Intermediate positions can also be detected by determining, according to a specific logic, whether one of the adjacent switching positions is selected.

For example, as in 2 at position N the code 110 is used, while between N and D / S the code 111 and as in 4 at position D / S the code 011 is used. This results in a Hemming distance of one.

Similarly, at position N, the code 110 can be used again. Between N and R can be used as code 001. At the position R can as in 5 be used as code 100.

For any intermediate positions, codes 111 and 001 may be used.

As long as the software knows which position it is in, logic 111 can be used for "switch back" and 001 for "switch up".

In 4 is the switching stage D / S by two bright lower surfaces 204 and a dark upper surface 204 (011). It is in the visible range 200 the active switching stage D / S centered and highlighted, while the sequence of inactive switching stages is shown laterally offset and not highlighted.

In 5 is the switching stage R by a bright upper surface 204 and two dark lower surfaces 204 (100) coded. It is in the visible range 200 the active switching circuit R centered and highlighted, while on both sides thereof, the inactive switching stages are not shown highlighted.

In 6 is the switching stage P by an upper bright surface 204 , a dark middle surface 204 and another lower bright area 204 (101) coded. In the visible area 200 the active switching stage P is centered and highlighted. The inactive switching stages are not highlighted on the side.

The number of photodiodes 206 to extend the logic and thus also the Hemming distance can be extended.

Alternatively, both the freezing of the image and the correct display can be determined with the aid of at least one photodiode and different frequencies at the respective switching positions. For example, a frequency of 50 Hz may be used in P, a frequency of 70 Hz in position R, a frequency of 90 Hz in position N and a frequency of 110 Hz in position D.

The 7 to 12 show representations of display devices 102 according to further embodiments of the present invention. The display devices 102 correspond substantially to the display devices in the 1 to 6 ,

In the in the 7 to 10 illustrated embodiments, the control device 112 additionally a separate light source 700 to illuminate the code area 202 on. It is in the 7 and 8th the light of the light source 700 through a light guide 702 on one of the photosensors 206 opposite side of the imaging element 304 and the lens 302 directed. In the 9 and 10 are are light sources 700 on the same side of the imaging element 304 arranged while on the opposite side of the element 304 a reflector 900 is arranged.

The illumination module 208 is intentionally made smaller, so only the display area 200 is covered. This allows the display (LCD / TFT) display module 110 with glass 302 by driving certain pixels in the active area 204 be used to detect certain switching positions.

This particular IR light is on the display 110 decoupled and coupled into this. Depending on the switching position, active areas 204 be opened using the display control, so that the coupled IR light to the located below the display module 110 located IR photodiodes 206 is allowed through.

The variant is due to the use of IR light and IR photodiodes 206 not prone to the light of day.

In other words, it is an area of the display 110 released to use this to active areas 204 to open for certain switch positions.

Is an active area 204 of the display 110 Released, the IR light from the IR LED can pass through the display 110 get where this to one on the display glass 302 attached reflector 900 reflected and on the adjacent sensor 206 meets. The principle of a reflection sensor is used. Here, for example, the same signal logic can be used as in the 2 to 6 ,

The number of sensor pairs for expanding the logic and thus also the Hemming distance can be extended as desired.

Alternatively, this also works in reverse, with the light of the display 110 via light guide 702 to the sensors 206 to be led.

In the 11 and 12 will ever be a light guide 702 used that by the respective area 204 of the code area 202 shining light of the lighting device 208 to one photo sensor each 206 to lead.

In this variant, in addition to the display, another light guide 702 used, in which IR light is coupled.

This light guide 702 can either be in the display module 110 , or integrated directly in the display bezel by a multi-component injection molding.

13 shows a flowchart of a method 1300 for operating a display device according to an embodiment of the present invention. The procedure 1300 can work on a controller, such as in 1 is shown executed. The procedure 1300 has a step 1302 sending, one step 1304 of receiving and one step 1306 of checking. The procedure 1300 requires a display device with a display and a control device. In step 1302 of transmission, an indication signal is sent to the display device. The display signal represents an image content to be displayed on the display and a target reference feature to be displayed by the display. In step 1304 of receiving, a control signal is received from the control device. The control signal represents an actual reference feature indicated by the display. In step 1306 the checking is a proper function of the display device using the reference reference feature and the actual reference feature checked.

The embodiments described and shown in the figures are chosen only by way of example. Different embodiments may be combined together or in relation to individual features. Also, an embodiment can be supplemented by features of another embodiment.

Furthermore, method steps according to the invention can be repeated as well as carried out in a sequence other than that described.

If an exemplary embodiment comprises a "and / or" link between a first feature and a second feature, this can be read so that the embodiment according to one embodiment, both the first feature and the second feature and according to another embodiment, either only the first Feature or only the second feature.

LIST OF REFERENCE NUMBERS

100

Control device for driving a display device

102

display device

104

vehicle

106

Providing device

108

evaluation

110

display

112

control device

114

image content

116

Vehicle control unit

118

image signal

120

Reference characteristic, reference reference feature

122

display signal

124

Image, actual reference feature

126

control signal

128

fault signal

120

Storage

200

viewing area

202

code area

204

surfaces

206

sensors

208

lighting device

210

first light sources

212

second light sources

300

focusing screen

302

Window

304

imaging element

306

Part of the light

700

light source

702

optical fiber

900

reflector

1300

Method for operating a display device

1302

Step of sending

1304

Step of receiving

1306

Step of checking

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

• EP 0856792 B1 [0003]

Claims (13)

Procedure ( 1300 ) for operating a display device ( 102 ), which has a display ( 110 ) and a control device ( 112 ), the method ( 1300 ) has the following steps: send ( 1302 ) of an indication signal ( 122 ) to the display device ( 102 ), whereby the indication signal ( 122 ) one on the display ( 110 ) image content to be displayed ( 114 ) and a through the display ( 110 ) to be displayed reference reference feature ( 120 represents; Receive ( 1304 ) of a control signal ( 126 ) by the control body ( 112 ), the control signal ( 126 ) on the display ( 110 ) displayed actual reference feature ( 124 represents; and checking ( 1306 ) of an intended function of the display device ( 102 ) using the desired reference feature ( 120 ) and the actual reference feature ( 124 ). Procedure ( 1300 ) according to claim 1, wherein in step ( 1302 ) of the transmission as the reference reference feature ( 120 ) a nominal image refresh rate of the display ( 110 ), in step ( 1304 ) of receiving as the actual reference feature ( 124 ) one of the control equipment ( 112 ) recorded actual image refresh rate of the display ( 110 ) Will be received. Procedure ( 1300 ) according to any one of the preceding claims, wherein in step ( 1302 ) of the transmission as the reference reference feature ( 120 ) in addition to the image content ( 114 ) on the display ( 110 ) optical target code to be displayed ( 120 ), in step ( 1304 ) of receiving as the actual reference feature ( 124 ) by the control body ( 112 ) on the display ( 110 ) detected actual code is received. Procedure ( 1300 ) according to claim 3, wherein in step ( 1302 ) of transmission as a target code ( 120 ) a pattern of distinguishable areas ( 204 ) is sent. Procedure ( 1300 ) according to one of claims 3 to 4, wherein in step ( 1302 ) of sending the image content ( 114 ) than in a visible display area ( 200 ) of the display ( 110 ) and the target code ( 120 ) than in a hidden reference area ( 202 ) of the display ( 110 ) are to be displayed. Procedure ( 1300 ) according to any one of the preceding claims, wherein in step ( 1302 ) of sending from the image content ( 114 ) dependent reference reference feature ( 120 ) is sent. Procedure ( 1300 ) according to any one of the preceding claims, wherein in step ( 1300 ) of sending the image content ( 114 ) is transmitted in a first wavelength range and the reference reference feature ( 120 ) is transmitted in a second wavelength range. Control unit ( 100 ) for driving a display device ( 102 ) with a display ( 110 ) and a control device ( 112 ), whereby the control unit ( 100 ) is designed to facilitate the process ( 1300 ) according to one of the preceding claims in corresponding facilities ( 106 . 108 ). Display device ( 102 ) with a display ( 102 ) and a control device ( 112 ), whereby the display ( 110 ) is adapted to a by a display signal ( 122 ) predetermined image content ( 114 ) and also by the display signal ( 122 ) predetermined reference feature ( 120 ), the control device ( 112 ) is adapted to the displayed reference signal ( 120 ) in a control signal ( 124 ). Display device ( 102 ) according to claim 9, wherein the control device ( 112 ) at least one photosensitive sensor ( 206 ) for mapping the reference feature ( 120 ) having. Display device ( 102 ) according to one of the preceding claims, in which the display ( 110 ) a visible display area ( 200 ) for the image content ( 114 ) and a hidden reference area ( 202 ) for the reference feature ( 120 ) having.  Computer program adapted to carry out the method according to one of the preceding claims. A machine readable storage medium storing the computer program of claim 12.

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