WO2015197490A1

WO2015197490A1 - Apparatus, system and method for determining a position on a display apparatus

Info

Publication number: WO2015197490A1
Application number: PCT/EP2015/063820
Authority: WO
Inventors: Florian VAN DE CAMP
Original assignee: Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
Priority date: 2014-06-24
Filing date: 2015-06-19
Publication date: 2015-12-30
Also published as: DE102014212084B3

Abstract

An apparatus for determining a position of a mobile apparatus comprises a display apparatus that is designed to display a location-variant colour position image. The apparatus additionally comprises a reception apparatus that is designed to receive a received signal from the mobile apparatus, which received signal has colour information with regard to at least one colour detected by the mobile apparatus. The apparatus additionally comprises a computation apparatus that is designed to evaluate the received signal in order to control the display apparatus with regard to a location at which the location-variant position image is displayed on the basis of the evaluation of the received signal, and in order to take the colour information as a basis for determining the position of the mobile apparatus with regard to the display apparatus.

Description

Device, system and method for determining a position on a display device Description

The present invention relates to a device, system and method for determining a position of a mobile device, such as a tablet computer, relative to a display device. Furthermore, the invention relates to a method for a camera-based self-localization of mobile terminals.

When interacting in multi-display environments, there are cases where a smaller screen is placed on a larger screen. An example of such a case is the removal of a smartphone (smart phone = smart phone, extended functionality mobile phone) or a tablet computer on a table display. This interaction form offers various additional functionalities. The simplest application is the intuitive transfer of data from the larger display to the mobile device or vice versa. More complex is the use of the mobile terminal as a loupe or so-called overlay, ie a superimposition of image contents.This, especially useful in map displays meaningful function, represents on the mobile device exactly the display section of the large display, which of the terminal Such a situation is illustrated in Fig. 7. A mobile terminal 92 may instead of an identical representation also display the image contents of a display device 94 with a magnification factor or display additional information.

Both for the functionality of the transmission, but especially for the functionality of the "overlay", it is necessary to determine the position and / or the displacement of the mobile terminal on the large display. Methods for marker-based position determination or tracking, as they are known, for example, from DE 10 2004 046 151 B4, make use of the fact that the table display used is a rear projection display. This makes it possible with a camera to record the bottom of the table and thus the bottom of the terminals on which special brands are attached. The process is very robust, but requires a rear projection display or a special display with built-in cameras. In addition, a modification of the terminals is necessary, such as by attaching the brands. Use of this method in a public space, e.g. In the form of smartphones It is therefore not possible or only possible to a limited extent on an information display in a shopping center.

Fig. 8 shows an illustration of a corresponding system with a tablet computer 95a or 95b, on the underside of which markers 96 are mounted in order to enable localization.

Methods for ultrasound-based tracking, as described, for example, in Holmquist, Saneblad and Gaye, 2003, use an ultrasound-based method. Such a system is actually designed to detect the position of highlighters on a whiteboard and thus digitally record what has been written. By attaching the pen caps to a mobile terminal, this can also be located and a functionality similar to the marker-based tracking can be achieved. The main disadvantage of this approach is the necessary modification of the terminal. The experimental sticking of the pen caps is not conceivable in any real use and would require specially adapted terminals.

It would therefore be desirable to have a concept that enables a simplified localization of a mobile device relative to a display device.

The object of the present invention is to provide a concept for a localization of a mobile device with respect to a display device that can be used for any camera-based mobile device, and that makes a hardware modification of the mobile device unnecessary for this.

This object is solved by the subject matter of the independent patent claims.

A core idea of the present invention is to have realized that the above object can be achieved by a mobile device transmitting color information regarding an unfocused object area detected by a sensor of the mobile device by means of a reception signal. Based on the color information as well as at a time when the received signal is received and based on the knowledge of when the corresponding color is displayed at a location of the display device, the location where the mobile device relates to the display device is determined. This can be done without focusing the object area and by evaluating the color information in the object area, so that the concept is applicable to almost all mobile devices having a camera, such as mobile phones or tablet computers. In one embodiment, a device for determining a mobile device includes a display device configured to display a location-variant colored position image. The apparatus further comprises a receiving device configured to receive a received signal from the mobile device having color information relating to at least one color detected by the mobile device. The apparatus further comprises a computing device configured to evaluate the received signal to control the display device with respect to a location where the location-variant position image is displayed based on the evaluation of the received signal, and based on the color information, determine the position of the mobile Device with respect to the display device to determine.

It is advantageous in this exemplary embodiment that based on a color or color distribution detected by the mobile device in the object area, i. H. a portion of the display device, the color distribution, d. H. the color information of the received signal can be converted by the computing device into a relative position of the mobile device with respect to the location-variant colored position image. Based on the knowledge of where the location-variant location image is displayed, the location of the mobile device relative to the display device can be determined. Furthermore, by means of a control of the display device with respect to the location at which the colored position image is displayed, a new shift of the mobile device with respect to the display device can be determined.

According to another embodiment, the receiving device is configured to receive a plurality of temporally spaced color information. The computing device is configured to continuously determine the location of the mobile device relative to the display device based on the plurality of color information.

An advantage of this embodiment is that based on a displacement or movement of the mobile device relative to the display device or relative to the location-variant position image, a variable color or color distribution can be detected by the mobile device and sent to the receiving device by means of the received signal, so that by means of the calculation device a tracking of the movement or displacement of the mobile device with respect to the display device is made possible (so-called tracking). For example, the temporal spacing may be based on a rate of acquisition of the sensor of the mobile device, such as a camera, such that the position of the mobile device is continuously enabled for a plurality or all of the images captured by the camera. According to a further embodiment, the location-variant position image comprises at least two segments which have a different color from each other, wherein the segments are arranged so that a color from a point within the location-variant position image on which a first color is arranged, along a shift direction along which the mobile device is shifted, a point is reached at which a second color is arranged.

It is advantageous in this embodiment that, when the mobile device is shifted from the segment in which the first color is arranged, toward a segment in which the second color is arranged, this is determined by the color information from the computing device can and with knowledge of a dimension of the colored position image and the arrangement of the segments in the position of the mobile device with respect to the display device is transferable. This can be done independently of a background image displayed on the display device, so that interference by the background image with respect to the position determination is reduced or prevented.

According to a further embodiment, the location-variant position image comprises four segments which have mutually different colors, wherein the four segments are arranged such that starting from a central region of the location-variant position image, in each case a point is reached along which a first color along a first displacement direction a second shift direction, a second color, along a third shift direction, a third color and along a fourth shift direction, a fourth color is arranged.

It is advantageous in this exemplary embodiment that two of the displacement directions can be arranged antiparallel or not parallel to each other, and thus based on the color information, a two-dimensional displacement of the mobile device with respect to the display device can be detected with high precision.

According to another embodiment, the computing device is configured to control the display device to shift the location-variant position image when the color information differs from reference information obtained when a sensor of the mobile device is centered over the location-variant position image a direction along which the location-variant position image is shifted based on the color information. An advantage of this embodiment is that the location-variant position image, after a position of the mobile device is determined, arranged centered with respect to the sensor, that can be displayed and a further displacement of the mobile device based on the displacement relative to the reference position can be determined.

According to a further embodiment, an apparatus for determining an initial position of a mobile device comprises a display device which is designed to display a location-variable initialization image having an initial color. The apparatus further comprises a receiving device configured to receive a received signal from the mobile device having color information regarding the initial color of the location-variant initialization image captured by the mobile device. The device further comprises a computing device that is designed to evaluate the received signal. The computing device is further configured to control the display device with respect to a location at which the location-variable initialization image is displayed, and to determine the initial position of the mobile device relative to the display device based on the received initial color information.

It is advantageous in this exemplary embodiment that when the mobile device is moved with respect to the display device for the first time or at a large displacement speed, the position can be determined by means of the colored initialization image. The initialization image may be, for example, a bar that largely or completely covers a display direction of the display device, such as height or width, and moves across the display device in a different direction. If the mobile device informs by means of the received signal that the initialization image or its color is detected, the computing device can determine the position of the mobile device with respect to the direction along which the bar has been displaced. According to a further embodiment, the computing device is configured to drive the display device to shift a first color initialization image along a first direction and a second color initialization image along a second direction, such that a position of the mobile image is based on the color information relative to the colorized initialization images Device with respect to the two directions can be determined. If the two initialization images have the same color, they can be displayed in chronological succession on the display device, so that based on a knowledge of which of the initialization images is displayed at a time or time interval at which the received signal is received, it can be determined in which of the respective areas the mobile device is arranged. Alternatively, the initialization images may have two different colors from each other and displayed simultaneously. As a result, the initial position determination can be carried out with a reduced expenditure of time.

According to a further exemplary embodiment, a device is designed to determine the initial position in a first step and to determine a position or rotation change of the mobile device in a second step. It is advantageous in this exemplary embodiment that color information obtained based on the initial position can be stored with reference to the position image as reference information, so that the position or rotation change can be determined based on the reference information and can be obtained for various mobile devices, so that a precision the position determination is increased.

According to a further embodiment, a system comprises a device for determining a position or initial position of the mobile device and the mobile device. The mobile device is configured to at least partially detect an object area displayed by the display device. In the object area, the location-variant position picture or the initialization picture can be displayed at least temporarily.

The mobile device is designed to determine the color information based on the color of the detected colored location-variant position image or of the colorized initialization image when the location-variant position image or the initialization image is detected, and to send the reception signal with the color information.

According to another embodiment, the mobile device is configured to determine a color distribution within the object area and to transmit the reception signal with the color information based on the determined color distribution.

An advantage of this embodiment is that even slight displacements of the mobile device with respect to the display device or the location-variant position image of the mobile device and thus can be detected by the computing device and the position determination can be carried out exactly. Further embodiments provide methods for determining a position and an initial position of the mobile device. Further embodiments relate to a computer program. Further advantageous embodiments are the subject of the dependent claims.

Preferred embodiments of the present invention will be explained below with reference to the accompanying drawings. Show it:

1 is a schematic block diagram of a device for determining a position of a mobile device according to an embodiment;

2a is a schematic plan view of a color position image with two segments, which is variably represented on a display device according to an embodiment;

2b is a schematic plan view of a colored position image having four segments, each having a mutually different color according to an embodiment;

2c is a schematic plan view of a colored position image, which has the four outer segments and also a fifth segment, which is arranged centrally with respect to the colored position image according to an embodiment.

FIG. 2 d shows a schematic plan view of a color position image which, compared with the colored position image, comprises only the four outer segments according to an embodiment; FIG.

2e shows a schematic illustration of a colored position image which has a circular base area and comprises three segments according to an exemplary embodiment;

3a shows a schematic representation of a device for determining the position of the mobile device according to an embodiment; Fig. 3b is a schematic side sectional view of the device of Fig. 3a;

4 is a schematic illustration of a device configured to determine an initial position of the mobile device according to an embodiment;

5a is a schematic plan view of an initialization image which is displaced along a display direction according to an exemplary embodiment;

5b shows a schematic plan view of an alternative initialization image, which has a triangular geometry in relation to the initialization image from FIG. 5a, according to an exemplary embodiment;

6 is a schematic block diagram of a system including the device of FIG. 1 and the mobile device according to one embodiment;

7 shows a large-scale display with a mobile terminal, which represents the display section of the large-scale display which is covered by the terminal; according to the prior art; and

Fig. 8 is an illustration of a system with a tablet computer, on the underside of which tags are attached to enable localization, according to the prior art. Before embodiments of the present invention are explained in more detail in detail with reference to the drawings, it is pointed out that identical, functionally identical or equivalent elements, objects and / or structures in the different figures are provided with the same reference numerals, so that shown in different embodiments Description of these elements is interchangeable or can be applied to each other.

Reference will now be made to an illustration of image information on a display device, such as a display. To better understand this different coordinate systems are used, which are described as an example Cartesian. In this case, a notation x, y or z refers to an x or y direction along dimensions of the display device. The x or y direction can, for example, be a height he / long or a width of the screen. The z direction refers to a direction along a surface normal of the screen surface, which is perpendicular to the x and y directions. A notation x 'or y' refers to a respective direction within an image content which may be shifted or rotated relative to the display device and thus statically or variably with respect to the x / y / z coordinate system. Such embodiments are not intended to limit embodiments described below. Rather, the coordinate systems can be arbitrarily converted into one another or into other coordinate systems, for example in polar, spherical or cylindrical coordinate systems, without restricting the functionality of the exemplary embodiments. Furthermore, the x-direction and the y-direction can be arbitrarily arranged in space.

1 shows a schematic block diagram of a device 10 for determining a position of a mobile device 12. The device 10 comprises a display device 14, a receiving device 16 and a computing device 18. The display device 14 is designed to display a location-variable colored position image 22 , The colored location-variant position image 22 can be detected by the mobile device 12 by means of a sensor 24, for example a camera. By means of a received signal 26, which is transmitted by the mobile device 12 and which has color information relating to the color of the location-variant position image 22 detected by the mobile device, the mobile device 12 notifies, for example, that the location-variant position image 22 by means of the sensor 24 was recorded.

The device 10 is designed to receive the reception signal 26 by means of the receiving device 16. The receiving device 16 is coupled to the computing device 18, so that the received signal 26 can be evaluated by the computing device 18. The computing device 18 is designed to evaluate the received signal 26. The computing device 18 is further configured to control the display device 14 with respect to a location at which the colored location-variant position image 22 is displayed on the display device 14. The computing device 18 is further configured to determine the position of the mobile device 12 relative to the display device 14 based on the color information. This is done, for example, so that the location-variant position image 22 has a color, for example, blue, red, green, yellow or a mixture thereof. The received signal may have the color information, for example, such that this conclusion allows the color to be detected by the camera, for example, to be detected in a percentage or acquired at a location within the corresponding image area. The percentage may, for example, at least 10%, at least 30%, at least 50% or more, of the colors within the captured image area. The image area can, for example, have a local coordinate system, for example in the form of pixel addressing, so that a color can be assigned to a location within the local coordinate system.

The display device 14 may be, for example, a large screen (large display). For example, the mobile device 12 is smaller than the display device 14. Thus, for example, the display device 14 may be larger, i.e., dimmed, along a first direction, such as a width direction, which is parallel to an x direction. H. Be wider than the mobile device 12 along a height direction, for example, is arranged perpendicular to the width direction along a y-direction in space, the display device 14 and the mobile device 12 may have an approximately equal dimension. In simple terms, the mobile device 12 may have an approximately equal height and a smaller width with respect to the display device 14 and may be displaceable relative to the display device 14 with respect to the width direction (x).

The mobile device 12 may be, for example, a tablet computer, a smartphone (extended functionality mobile phone), or another mobile device with sensor and communication capabilities. These include, for example, audio players that have both Internet access and a camera and possibly a screen.

The mobile device 12 can be placed on the display device 14, for example, if the display device 14 is realized in the form of a desktop display. Alternatively, the display device 14 may, for example, be a wall display and the mobile device 12 may be held on the display device 14 or otherwise disposed relative to the wall display. This can be done such that, as when placed on a table, a mechanical contact (touch) and thus a small or minimal distance between the mobile device 12 and the display device 14 is formed. Alternatively, the mobile device 12 may also be kept spaced from the display device 14. By way of example, the device 10 will be described below so that the display device 14 is a desk-top display. If the mobile device 12 is positioned with respect to the display device 14 in such a way that the sensor 24 (camera) detects the colored location-variant position image 22, then the camera can recognize the color of the location-variant position image 22. This is possible even if a distance between the mobile device 12 and the display device 14 is so small that a focus of the camera or the sensor 24 with respect to the location-variant position image 22 is prevented. In simple terms, the sensor 24 can detect the color of the location-variant position image 22, even if the image is not in focus.

If the mobile device 12 is displaced relative to the display device 14, for instance along the positive or negative x-direction, then the color determined by the mobile device 12 changes, for example because the display device 14 displays a different color outside the location-variant position image 22 in a background image , than that of the location-variant position image. The color detected by the sensor 24 therefore changes, for example, in such a way that a mixed color between the background color and the color of the location-variant position image is detected by the sensor 24. Alternatively, the sensor 24 may also be designed to detect a color distribution within the object area that it detects. The mobile device 12 can then, for example, the color distribution, such as color of the location-variant position image 22 in a first, for example. Right or upper image area and the background color in a left or bottom image area, if the mobile device 12 along the negative x- Direction is shifted, determine and send this color information by means of the received signal 26. Alternatively, the position image can also have a plurality of segments, so that the position determination can be based on an arrangement of the segments independently of the background image.

Based on the color information, the computing device 18 is configured to determine that the mobile device 12 is shifted with respect to the display device 14 along the negative x-direction (eg, left). This can be made possible by the fact that the location and the color of the location-variant position image of the computing device 18 are known or accessible.

The computing device 18 is further configured to control the display device 14 to display (shift) the location-variant position image 22 at another location. This can be done until the color information in the receive signal 26 indicates that the location-variant position image 22 is again detected with respect to the sensor 24, as it has been received in an initial state. The initial state may include, for example, a defined, approximately centered representation of the location-variant position image 22 with respect to the x-direction and relative to the sensor 24. Based on the position determined by the computing device 18, at which the display device 14 displays the location-variant position image 22 at that time, is new position of the mobile device 12 with respect to the display device 14 by the computing device 18 determinable.

In simple terms, the control of the display device 14 by the calculation device 18, the display of the colored, spatially variant position image 22 and the feedback of the mobile device 12 by means of the received signal 26 form a control or regulating loop.

The mobile device 12 may, for example, have a screen which is arranged on a side which is arranged facing away from the sensor 24 and / or display device 14. Thus, the sensor 24 can be arranged on a side opposite the screen and the mobile device 12 can be arranged relative to the display device 14 such that the side on which the sensor 24 is arranged faces the display device 14. For example, such a viewer of the display device 14 may also view the screen of the mobile device 12.

Based on the position determined by the computing device 18, further data may be exchanged between the device 10 and the mobile device 12. For example, the position of the mobile device 12 determined by the computing device can be communicated to it, so that the mobile device 12 can determine or select information to be displayed on the screen thereof. The information to be displayed can be, for example, an optionally enlarged section of image content displayed on the display device 14 in the area of the mobile device (magnifying glass function). Alternatively, a superimposed representation with further, non-pictorial information is conceivable, such as opening hours of shops, if the image content relates to a site plan in a mall (overlay function). Alternatively, for example, a user input on the mobile device 12 or on the screen thereof can be communicated to the device 10, for instance by means of the received signal 26 or another signal, so that the device 10 controls the user input with the position of the mobile device 12 with respect to the display device 14 can link.

The received signal 26 can be transmitted or received, for example, by means of a wireless local area network (WLAN), an internet connection, a Bluetooth® connection or another wireless communication interface. Alternatively, a transmission of the received signal 26 from the mobile device 12 to the device 10 may also be wired, for example via a local Wired network interface (Local Area Network - LAN or personal network - PAN) or the like.

It is advantageous that, despite a reduced or even minimized distance between the mobile device 12 and the display device 14, the mobile device 12 can recognize the color or the color distribution of the colored location-variant position image 22, so that a modification of the mobile device 12 with respect to hardware Components can be dispensed with. Furthermore, detection and / or resolution of a pattern can be dispensed with, so that position detection can be robust with conventional sensor or camera-based mobile devices.

Alternatively, the display device 14 may also be designed such that the mobile device 12 can be positioned, rotated and / or displaced along the at least one further direction thereof

FIG. 2a shows a schematic plan view of a colored position image 28a, which can be displayed variably on a display device. The colored position image 28a has two segments 32a and 32b, which comprise a mutually different color. The colored position image 28a has a size along an x 'direction and a y' direction that is larger than a detection range 34 of the mobile device. That is, when the colored position image 28a centered with respect to the sensor of the mobile device 34 is displayed on the display device, the detection range 34 is within an area of the colored position image 28. The segments 32a and 32b are arranged so that a color from a point 36 within the colored position image 28a, on which the color of the first segment 32a is arranged, ends along a displacement direction 37, so that a point 36b is reached the color of the second segment 32b is arranged. That is, the color or color distribution within the detection area 34 changes depending on the size of the detection area 34 when the detection area 34, and hence the mobile device, is shifted along the shift direction 37 with respect to the colored position image 28a. If the changed color distribution is determined by the mobile device and transmitted to the device 10 as color information by means of the received signal, then a changed relative position of the mobile device 12 with respect to the colored position image 28a and thus of the display device can be determined with a high degree of accuracy. If the changed relative position is based on a color component and / or based on a dominant color in the detection mode 34, such a determination may be robust and error-prone.

2b shows a schematic plan view of a colored position image 28b, which has four segments 32a-d, each of which has a different color from one another, as indicated by the mutually different hatchings. The colored position image 28b has a randomly selected geometry of the base area. The footprint is larger than the detection area 34 of the mobile device sensor. The four segments 32a-d have a common touch point 38. The segments 32a-d are arranged such that when the detection area 34 is centered with respect to the touch point 38, the four segments 32a-d are detected by the mobile device with an approximately equal area. For example, if the detection area 34 is round, each of the four sectors 32a-d may be detected by the mobile device 12 in the form of a four-circle circle.

If the mobile device 12 and therefore the detection area 34 are displaced in an arbitrary direction along the x'- and / or y'-axis in positive and / or negative respective direction with respect to the colored position image 28b, the color distribution changes approximately based on changed Color components within the detection area 34, which can be determined by the mobile device 12. For example, when the detection area 34 is shifted along the positive x 'direction, the proportion of the color of the segment 32d decreases, whereas the proportion of the color of the segment 32b is increased. Further, a relative position of the segments 32a-d with respect to a center of the detection area 34 also changes. If, following the previous example, the detection area 34 is shifted along the positive x 'direction with respect to the colored position image 28b, the color of the segment 32b is by the mobile device, for example, also detectable at image positions, which are arranged with respect to the center of the detection area 34 along the negative x'-direction. Both the position of a color within the detection area 34 and the color distribution can be transmitted by the mobile device, such as the mobile device 12, by means of the reception signal, such as the reception signal 26. Alternatively, the shift of the detection area 34 may also be relative to the y 'direction or a combination of x' direction and y 'direction, so that the color distribution may change with respect to three or four colors.

Fig. 2c shows a schematic plan view of a colored position image 28c, which has the four segments 32a-d, which have a mutually different color, as indicated by the mutually different shading. The colored positi- An image 28c further includes a fifth segment 32e centered with respect to the colored position image 28c and including a fifth color different from the colors of the four other segments 32a-d. The fifth segment 32e may have a dimension along the x 'and y' directions that is substantially equal to the size of the detection region 34 along the respective direction. For example, if the detection area 34 is round, the segment 32e may also be round and have a diameter that substantially corresponds to the diameter of the detection area 34 at the object plane of the colored position image 28c. Substantially equal here means that the detection area 34, when centered with respect to the position image 28c, can be arranged completely within the segment 32e. Alternatively, the detection area 34 may be larger so that one or more of the segments 32a-d may also be detected by the mobile device 12 when the detection area 34 is centered with respect to the colored position image 28c. Alternatively, the detection area 34 can also have a polygonal, elliptical or other shape, which is based on the design of the camera of the mobile device and can be independent of the configuration of the position image. An enlarged compared to the segment 32e detection area 34 is indicated by the dashed line. The segment 32e may be referred to as an inner region. The color of the inner region 32e may be a reference color, such as white, where the color white may mean an overlay of the colors red, blue and green, such as according to the additive color system. Alternatively, the inner region may also have any other color. If the detection area 34 is smaller than the inner area 32e (solid line of the detection area 34) and the detection area 34, ie, the mobile device, is shifted in any direction with respect to the colored position image 28c, one of the colors of the segments 32a-d becomes pushed the detection area 34 so that it can be detected by the mobile device. If the detection area 34 is greater than the inner area, a color distribution of the segments 32a-d and possibly of the inner segment 32e within the detection area 34 changes as a result of the displacement.

Starting from the midpoint of the segment 32e, one color or one of the segments 32a-d is reached along each of the four displacement directions along the respective positive and negative 'and y' directions. This color can be sent as color information by means of the received signal, so that the calculation device is designed to allow the change of the relative position between the detection area 34, ie the mobile device, and the colored position image 28c, ie the display device determine. Thus, the computing device is configured to determine the position of the mobile device 12 relative to the display device. Subsequently, the computing device is designed, for example, to control the display device in such a way that it displays the colored position image 28c centered around the specific location, ie centered with respect to the detection area 34.

It is advantageous on the inner region 32e that a change in the position of the mobile device relative to the display device can be determined based on one or more colors of the segments 32a-d which are dominant relative to the color of the inner region. The color of the inner area 32e can be used as reference information, so that the location-variant position image can be considered centered with respect to the sensor of the mobile device, if the location-variant position image is arranged with respect to the mobile device such that the color of the inner area 32e in one predetermined amount, about at least 50%, at least 70% or at least 90% in the form of the color information is received.

FIG. 2d shows a schematic plan view of a colored position image 28d which, compared with the colored position image 28c, only comprises the four segments 32a-d. The colored position image 28d has a round base area, which encompasses the four segments 32a-d. The four segments 32a-d are each designed as quarter circles arranged adjacent to one another.

If the intersection point 38 of the four segments 32a-d is located within the detection range of the mobile device sensor, then, based on an arrangement of the colors of the segments 32a-d within the detection range, in addition to a position of the mobile device, an orientation of the mobile device relative to FIG the display device 14 can be determined. Thus, a color distribution and / or an arrangement of colors within a local coordinate system of the detection area 34 may be part of the color information that is sent by means of the received signal. The computing device may be configured to align (rotation) the detection area and thus the mobile device with respect to the colored position image 28d and thus rotate the mobile device with respect to the display device, based on the color distribution of the colors within the local coordinate system of the detection area to determine.

Fig. 2e shows a schematic representation of a colored position image 28e, which has a circular base and three segments 32a-c having a mutually different color. The segments 32a-c are each as circle segments executed with a different surface area and have the common touch point 38.

For example, it is advantageous on segments with a different surface area that a segment having a color that is displayed on the display device 14 with a lower intensity than other colors of the colored position image 28e is displayed with an enlarged surface area. As a result, the corresponding lower intensity ink is displayed on a larger area, resulting in improved detection by the mobile device sensor. Alternatively, by means of a mutually different surface of the segments 32a-c, an unequal sensitivity of the sensor of the mobile device with respect to the colors of the colored position image 28e can also be compensated.

The segments 32a-c are arranged along a circumferential direction 42 of the colored position image 28e. That is, along the circumferential direction 42 arranged parallel to and within a circumference of the colored position image 28e, all of the direction-determining segments 32a-d are traversed. Direction determining means that based on the direction-determining segments 32a-c, the direction of displacement of the mobile device with respect to the positional image 28e and thus the display device can be determined. The inner region, as described for FIG. 2 c, may be a non-directional region, depending on the algorithm implemented.

The rotation, as described for the position image 28d, can also be determinable with other position images 28a, 28b, 28d or 28e, for example if the detection area 34 is larger than the segment 32e in the position image 28c, so that the segments 32a-d in a centered arrangement of the detection area 34 with respect to the colored position image 28c are also arranged within the detection area. Alternatively, for a determination of the rotation of the mobile device with respect to the display device, only one of the segments 32a-d may be arranged within the detection area, which (taking into account the arrangement of the inner area) within the local coordinate system of an image sensor of the camera local coordinate system of the detection area or the sensor of the mobile device and the coordinate system of the display device and / or another coordinate system, to which the display device is related, allows.

A base of a positional image 28a-e may have any shape, such as a round, an elliptical, a polygonal shape or a freeform. Also can the segments of a position image have the same or different shape. In particular, the embodiment of the segments 32a-e described above as a circular shape (segment 32e) or circular cutouts (32a-d) is to be understood merely as an example. Alternatively, other shapes, such as curved courses between segments are conceivable.

As is described, for example, for FIGS. 2c and 2d, an orientation of the mobile device relative to the positional image 28e or relative to the display device can be determined by means of the colored position image 28e.

Alternatively or additionally, the computing device may be configured to determine the orientation (rotation) of the mobile device relative to the display device based on data from position sensors of the mobile device. If the mobile device comprises charging sensors, such as acceleration sensors or sensors, which indicate tilting of the mobile device with respect to a gravitational field, and the mobile device transmits this data, for example by means of the received signal, the computing device can be designed to determine the orientation of the mobile device the display device based on the global orientation of the mobile device to determine.

In other words, in addition to the position of the mobile terminal for some applications, such as card overlays, even the rotation of the device (mobile device) on the large display is important. To determine the rotation, there are two possibilities. Most mobile devices have position sensors, which can deliver the rotation of the device very precisely. If no corresponding sensors are present, the determination of the rotation can take place via the colored position image. For example, the position image has a small or no white circle in the middle, as described for Fig. 2d. Compared to Fig. 2c, the colored position image of Fig. 2d is slightly modified, the white circle in the middle is removed, and the four color sections (sectors 32a-d) are correspondingly expanded, so that a circle with four different colored quarters is obtained. The tracking system then positions the disc (colored position image) such that the proportion of the four colors is always substantially equal to hold the position of the tracking disc under the camera of the mobile device. This may possibly lead to a more restless tracking, but allows by the arrangement of the colors relative to the camera to determine the rotation of these compared to the large display. For example, a tracking rate may be based on a refresh rate of the camera. For example, if the camera is designed to capture 30 frames per second, color information can be included in a comparable cycle. Are transmitted to the receiving device or the computing device means of the received signal.

3a shows a schematic representation of a device 30 for determining the position of the mobile device 12. The calculation device 18 is designed to control the display device 14 in such a way that it displays the colored position image 28c in a location-variant manner. The position image 28c has a dimension along the x-direction and the y-direction that is smaller than a corresponding dimension of the mobile device 12. If the mobile device 12 is positioned relative to the display device 14, for example, it is placed on it the positional image 28c is at least partially obscured by the mobile device 12.

By at least partially obscuring the positional image 28c, it is possible, in particular in applications in which a user views both the display device 14 and the mobile device 12, to reduce or prevent visual impairment or even interference for the user.

The device 30 or the computing device 18 is designed to control the display device 14 so that it positions the colored position image 28c approximately centrally with respect to the sensor of the mobile device 12. For example, the computing device 18 may be configured to determine reference information based on the reception signal 26 having the center positioning color information. This can be, for example, the color information itself. Alternatively, the reference information may already be stored in or for the computing device 18, for example in a reference information memory.

Moving the mobile device 12 with respect to the display device 14 along the x and / or y direction to a position along the x direction or yi along the y direction or about a z-axis, for example, perpendicular to the x- Direction and y-direction is rotated by an angle α, the reception signal 26 is received by the receiving device 16 with respect to the reference information changed color information. Based on the altered color information, the computing device 18 is configured to determine the position

and / or to determine the orientation of the mobile device 12 with respect to the display device 14, such as by the computing device being configured to compare the color information with the reference information. The computing device 18 is further configured to control the display device 14 in such a way that the colored position image 28c is also displaced and / or rotated, which means that the display device 14 can be activated such that it at least partially aligns the position image 28c with that for the color image mobile device certain location x ^ positioned. At least partially means that, for example based on calculation inaccuracies and / or detection inaccuracies of the sensor of the mobile device 12 position differences between a particular position and / or orientation and an actual position or orientation may arise. Furthermore, positional differences may result if there is a latency between a continuous movement of the mobile device 12, the transmission of the received signal 26, the calculation of the position by the computing device 18 and the driving of the display device 14, during which the mobile device 12 is further shifted. This can lead to the mobile device 12 being already further displaced relative to the specific position along the x-direction and / or vi along the y-direction or rotated by a further angle α. This can be compensated for by comparison with the reference information by redetermining the position. This means that the position or the position change, the rotation or a rotation change can be continuously determined by the computing device 18.

The receiving device 16 is further configured to receive an orientation signal 43 from the mobile device 12 having information regarding the global orientation of the mobile device 12. The receiving device 16 is designed to provide the computing device 18 with the orientation signal 43. The calculation device 18 is designed to determine the orientation, i. H. to determine the rotation or the angle α.

3b shows a schematic side sectional view of the device 30. With regard to the display device 14, the mobile device 12 is arranged, for example, placed on the display device 14. The mobile device 12 includes a camera 44 that is configured to detect an object area within the detection area 34. The colored position image 28 c is positioned so that it is partially disposed within the detection area 34. If the mobile device 12 is displaced, for example by a distance Δχ along the x direction, the color distribution or the image captured by the camera 44 changes. Based on the color information in the received signal, the computing device is designed to control the display device 14 so that it also shifts the position image 28c by the distance Δχ. The designation Δχ can also refer to a shift in the mobile direction 12 and thus the positional image 28c along one or more other display directions of the display device 14 relate.

The device 30 is configured based on the continuous determination of the position of the mobile device 12 to track movement and / or rotation thereof. The colored position image 28c may be referred to as a tracking disk.

In other words, the colored position image, the tracking disk, for example, is a graphic that represents a ring that is divided into four equal-sized color areas, as shown for FIG. 2c. This tracking disc will be displayed on the big screen, i. H. the display device 14, displayed at the location at which the mobile terminal has been located. For example, if the inner area includes a white color and the area of coverage is less than or equal in area and geometry, then the white interior of the disc is just below the camera of the device. If the mobile terminal is now displaced, one or two of the four colors appear in the field of vision of the terminal's camera, so that one or two or three of the four colors appear / appear in the field of vision of the terminal's camera. By arranging the colors within the detection area, it is possible to determine in which direction the device has been moved and the tracking disk will be moved in this direction until the white center is again under the camera.

By way of example, referring to the tracking disk 28c depicted in FIG. 2c, an example might look like this: the device is moved up, ie, in the positive y 'direction, so the camera is moved over the segment 32a, a portion of the ring. The section 32a has, for example, a red color. The camera recognizes the red color, transmits the information to the large display or to the receiving device and / or the computing device, which moves the tracking disk upwards. This is repeated until the camera rediscovers the white color. If the tracking disk is moved too far, the segment 32c, for example having a green color, will appear under the camera, which in turn will tell the system to move the disk 28c down. By making this adaptation continuously, the mobile terminal can be moved across the large display, wherein the tracking disk is always positioned under the camera of the terminal or is positioned there again. Due to the positioning of the camera on most mobile devices and the size of the tracking disk, this is usually almost completely obscured by the device and thus not visible to the user or only to a small extent. 4 is a schematic diagram of a device 40 configured to determine an initial position x ₀ / yo of the mobile device 12 along the x-direction and the y-direction, for example, before tracking is performed; as described, for example, for Figs. 1 and 3. Based on the initial position, reference color information can be obtained therefrom and / or a tracking of the mobile device 12 can be carried out.

For this purpose, the calculation device 18 is designed to control the display device 14 in such a way that it displays location-variant colored initialization images 46a and 46b. The location-variant initialization images 46a and 46b have, for example, a respective beam structure and a color, wherein the color of the location-variant initialization image 46a can be the same or different from the color of the location-variant initialization image 46b. The location-variant initialization image 46b also has, for example, a bar structure. In this case, a beam structure denotes a dimension of the location-variable initialization images 46a and 46b over large portions or a total respective dimension along the y- or x-direction of the display device 14. A large portion may, for example, at least 25%, at least 33%, at least 50% or another value of the respective display direction mean. The computing device 18 is designed to control the display device 14 so that it displaces the location-variant initialization image 46a, which is represented over large or entire areas of the extent of the display device 14 along the y-direction along the x-direction. If the location-variant initialization image 46a is arranged with respect to the sensor 24 of the mobile device 12, ie if the mobile device 12 detects the location-variant initialization image 46a or the color of the same, it transmits this by means of the color information in the received signal 26 to the reception device 16. Based on the received Color information, the computing device 18 is designed to determine the initial position x ₀ / y _{0 of} the sensor 24 and thus the mobile device 12 along the x-direction.

For example, the location-variant initialization image 46b is displayed along the entire dimension of the display device 14 along the x-direction. The computing device 18 is designed to control the display device 14 in such a way that it shifts the location-variant initialization image 46b along the y-direction. If the location-specific initialization image 46b is arranged with respect to the sensor 24, this can be communicated to the reception device 16 as part of the color information in the received signal 26. The computing device 18 is designed to be based on this color tion to determine the initial position y _{0 of} the mobile device 12 with respect to the y-direction of the display device 14.

The display device 14 may further be configured to display any graphical content 48, such as topographical data, maps, maps such as shopping malls or buildings, or the like. The mobile device 12 may be configured to display a portion 52 of the graphical data 48, wherein a perimeter of the portion 52 relative to the graphical data 48 is at least partially at the determined position

and / or the initial position x ₀ / yo. This means that by means of the displacement of the mobile device 12 with respect to the display device 14, the detail 52 shown is also variable.

The representation and displacement of the initialization images 46a and 46b can be used to determine the initial position x ₀ / y _{0 of} the mobile device 12 with respect to the display device 14. If the initial position x ₀ / yo is determined, the computing device 18 may be configured to control the display device 14 such that it fades out or no longer displays the initialization images 46a and 46b and displays a position image, for example one of the position images 28a-e, which enable tracking of the mobile device 12.

If the initialization images 46a and 46b have the same or similar color, the initialization images 46a and 46b may be sequentially displayed, that is, a time interval in which the initialization image 46a is displayed is limited to the time interval in which the initialization image 46b is displayed is, follows, the order is also interchangeable bar. The computing device 18 may be configured to determine, based on the knowledge of which of the initialization images 46a or 46b is being displayed and shifted, which position along the x-direction or y-direction shows the obtained color information or the respective colored initialization image. A respective time interval may be based on a dimension along which the initialization image is shifted. Further, a time interval may be based on a shift speed of the initialization image. If the display direction in x is, for example, 1.2 m and the initialization image is shifted along a distance of 1.0 m therein at a speed of 1 m / s (for example, because no sensor of the mobile device can be arranged at the edge) the time interval 1 s. The display directions, the shift speeds and / or the time intervals may be the same or different with respect to the x-direction and the y-direction. The displacement speed can be, for example, at least 0.1 m / s, at least 0.5 m / s or at least 1 m / s. The display directions may be a size in a range between see 0.5 m and 10 m, between 0.75 m and 8 m and between 1 m and 5 m or any other value.

On the other hand, if the initialization images 46a and 46b have colors different from one another, such as red and blue, green and yellow or another color combination, an assignment may be made based on the color information as to which color was detected, whether the received signal comprises detection of the initialization image 46a or 46b indicates. That is, the time intervals in which the respective initialization images 46a and 46b are displayed at least partially overlap, and in the time range in which the time intervals overlap, both bar structures are displayed on the display device 14.

The color or colors of the initialization image (s) 46a and 46b may be referred to as an initial color for determining the initial position x ₀ / y _{0 of} the mobile device 12 relative to the display device 14. The colors of the initialization images may be wholly or partially the same as or different from colors of the position image.

The device 40 may alternatively be configured to determine the initial position of the mobile device 12 with respect to the display device 14 only along a display direction x- or y. This may, for example, provide sufficiently accurate information if the mobile device 12 is displaceable only along one direction with respect to the display device 14, as described for device 10. In other words, an idea of the solution is based on the fact that practically all smartphones and tablets have a camera on their back. If a mobile device is placed on a desktop display or alternatively held on a wall display, the camera will perceive what is shown on the display at this point. For example, depending on the camera, this may be an area of approximately 15x15, 20x20, or 30x35 pixels or any other size that is not focused due to the small distance. But it is enough to recognize the dominant color of this area. To recognize the initial position of the mobile terminal on a large display, a colored, such as red, stripes, for example, laid horizontally across the display. The mobile terminal recognizes via the camera the moment in which the strip is exactly below it and reports this to the large display, which knows the position of the strip, as it indicates it. Thus, the horizontal position (x-axis) of the terminal can be determined on the display. The same can be repeated to determine the position on the y-axis. To speed up the process, it is too It is possible to use two differently colored stripes to determine the x- and y-axis positions simultaneously.

Although the initialization images 46a and 46 have been described as being displayed along each display direction of the display device 14 so as to completely cover this display direction, it is also conceivable that the initialization images only partially cover the display device along this display direction. Thus, for example, a smaller initialization image along this particular display direction can be shifted along the respective display device, displayed several times in succession.

5a shows a schematic plan view of the initialization image 46a, which is displaced along a display direction x or y. Along a direction transverse to the direction of movement, the initialization image 46a has a large dimension.

FIG. 5b shows a schematic plan view of an initialization image 46c, which has a triangular geometry in relation to the initialization image 46a. The triangular geometry leads to the initialization image 46c having a variable extent (thickness) along the displacement direction x / y. This enables, for example, that if the received signal contains information about how long the initialization image has been detected, the computing device can obtain information about which position along a height direction h the mobile device has detected the initialization image 46c. This allows the position of the mobile device 12 to be initially determined with respect to both display directions with respect to both display directions x and y by means of the one initialization image 46c. In principle, any other geometry of the initialization image is conceivable, such as comprising curved edges or a polygonal or elliptical shape or a freeform. Although in the above described embodiments devices have been described as determining the tracking or determinations of the initial position of the mobile device, the devices 10, 30 and / or 40 may be configured to perform both a determination of the initial position and a tracking of the mobile device 12 with respect to the display device.

If, for example, the mobile device 12 is brought to the display device 14 and a determination of the initial position is desired or desired, this can be done, for example, by means of a user input on the mobile device 12. Alternatively or additionally, user input may be on the display device or on another element of the respective device, indicating that communication to the mobile device is desired. FIG. 6 shows a schematic block diagram of a system 60 that includes the device 10 and the mobile device 12. The mobile device 12 is configured to at least partially detect an object area displayed by the display device. For this purpose, the mobile device 12 can be arranged adjacent to or on the display device. The mobile device 12 is further configured to determine the color information based on the color of the detected location-variant position image in the detected object area. Further, the mobile device 12 is configured to send the reception signal 26 with the color information. The mobile device 12 can be, for example, a tablet computer, a smartphone, an audio player or another mobile device with sensor and communication possibilities, on which a corresponding program product, for example in the form of an application (application = application - app). is stored, which initializes the corresponding functionality.

Alternatively or additionally, the system 60 may also include a device 30 or 40. For example. For example, the device 10, 30 or 40 may be designed to determine the initial position of the mobile device and subsequently display the location-variant position image at the determined initial position. The device 10, 30 or 40 can also be designed to deposit a color information received by the mobile device 12 with respect to the initial position for subsequent tracking as reference information. This makes it possible for a different reference position to be determinable for different mobile devices 12, so that an accuracy of the position determination with respect to various mobile devices 12 is increased.

Compared to the prior art, embodiments described above offer two additional advantages. In addition to the avoidable hardware modification of the mobile device and a hardware modification of the large display is avoidable. In particular, an adaptation of the large display for detecting the brands described above can be avoided. The approach presented here can in principle be realized with any large display. This means that the method can be used with any mobile devices, which allows, for example, the use in public spaces with the devices of passers-by. The knowledge of the position of a mobile terminal with respect to a large display allows a variety of applications. The solution presented here has the great advantage that it can be used without modification of the terminal. Therefore, one possible application is in public spaces where users can use their own terminals. An example would be an interactive information terminal, for example in a shopping center, an airport or a train station. By creating or placing a mobile device position-related additional information can be displayed or data transferred. If the mobile terminal is placed, for example, on a location plan displayed on the large display on a location, such as a shop, additional information, such as coupons, offers, directions, arrival or departure times or the like can be transferred to the mobile terminal.

Although some aspects have been described in the context of a device, it will be understood that these aspects also constitute a description of the corresponding method, so that a block or a component of a device is also to be understood as a corresponding method step or as a feature of a method step. Similarly, aspects described in connection with or as a method step also represent a description of a corresponding block or detail or feature of a corresponding device.

Depending on particular implementation requirements, embodiments of the invention may be implemented in hardware or in software. The implementation may be performed using a digital storage medium, such as a floppy disk, a DVD, a Blu-ray Disc, a CD, a ROM, a PROM, an EPROM, an EEPROM or FLASH memory, a hard disk, or other magnetic disk or optical memory are stored on the electronically readable control signals, which can cooperate with a programmable computer system or cooperate such that the respective method is performed. Therefore, the digital storage medium can be computer readable. Thus, some embodiments according to the invention include a data carrier having electronically readable control signals capable of interacting with a programmable computer system such that one of the methods described herein is performed.

In general, embodiments of the present invention may be implemented as a computer program product having a program code, wherein the program code is effective to perform one of the methods when the computer program product runs on a computer. The program code can also be stored, for example, on a machine-readable carrier. Other embodiments include the computer program for performing any of the methods described herein, wherein the computer program is stored on a machine-readable medium.

In other words, an embodiment of the method according to the invention is thus a computer program which has a program code for performing one of the methods described herein when the computer program runs on a computer. A further embodiment of the inventive method is thus a data carrier (or a digital storage medium or a computer-readable medium) on which the computer program is recorded for carrying out one of the methods described herein.

A further embodiment of the method according to the invention is thus a data stream or a sequence of signals, which represent the computer program for performing one of the methods described herein. The data stream or the sequence of signals may be configured, for example, to be transferred via a data communication connection, for example via the Internet.

Another embodiment includes a processing device, such as a computer or a programmable logic device, that is configured or adapted to perform one of the methods described herein.

Another embodiment includes a computer on which the computer program is installed to perform one of the methods described herein.

The embodiments described above are merely illustrative of the principles of the present invention. It will be understood that modifications and variations of the arrangements and details described herein will be apparent to others of ordinary skill in the art. Therefore, it is intended that the invention be limited only by the scope of the appended claims and not by the specific scope of the invention. The details presented with reference to the description and explanation of the embodiments herein are limited.

Claims

claims

Apparatus for determining a position of a mobile device (12) comprising: a display device (14) adapted to display a location-variant colored position image (22; 28a-c); a receiving device (16) configured to receive a received signal (26) from the mobile device (12) having color information relating to at least one color detected by the mobile device (12); and a computing device (18) configured to evaluate the received signal (26) to the display device (14) with respect to a location at which the location-variant position image (22; 28a-e) is displayed, based on the evaluation of the received signal (26) and to determine, based on the color information, the position (Xi, y of the mobile device (12) with respect to the display device (14).

Apparatus according to claim 1, wherein the receiving device (16) is adapted to receive a plurality of temporally spaced color information and wherein the computing device (18) is adapted to detect the position (x) of the mobile device (12) relative to the display device (14) continuously based on the plurality of color information.

Apparatus according to claim 1 or 2, wherein the location-variant position image (22; 28a-e) comprises at least two segments (32a-e) having different colors from each other, the segments (32a-e) being arranged such that a color is obtained from a point (36a) within the location-variant position image (22; 28a-e) on which a first color is arranged along a displacement direction (37) a point (36b) on which a second color is arranged ,

Apparatus according to any one of the preceding claims, wherein the location-variant position image (22; 28a-e) comprises four segments (32a-e) having different colors from each other, the four segments (32a-e) being arranged such that from a central region (38; 32e) of the location-variant position image (22; e) starting from a respective point (36a) is achieved, in which along a first displacement direction (+ x) a first color along a second direction of displacement (-x) a second color, along a third direction of displacement (+ y) a third color and along a fourth displacement direction (-y) a fourth color is arranged.

Apparatus according to any one of the preceding claims, wherein the location-variant position image (22; 28a-e) has an interior region (32e), the interior region (32e) having a color different from colors present in other segments (32a-d) ) of the location-variant position image (22; 28a-e) is different.

Apparatus according to claim 5, wherein said calculating means (18) is arranged to drive the display device (14) to shift the location-variant position image (22; 28a-e) when the color information differs from a reference information that results when a sensor (24; 44) of the mobile device (12) is centered over the location-variant position image (22; 28a-e), a direction (x, y) along which the location-variant position image (22; 28a-e ) is based on the color information.

Device according to one of the preceding claims, in which the calculating device (18) is designed to control the display device (14) so as to at least partially position the location-variant position image (22; 28a-e) at the specific location (xi, y) mobile device (12) positioned.

Apparatus according to claim 7, wherein the spatially variant position image (22; 28a-e) comprises at least two segments (32a-e) having color information different from one another and arranged along a circumferential direction (42) along which the at least two segments (32a-e) of the location-variant position image (22; 28a-e), wherein the reception signal (26) contains information regarding a color distribution within an object region (34) detected by the mobile device (12), in which the location-variant position image (34). 22; 28a-e), and wherein the calculation device (18) is designed to determine, based on the color distribution, an orientation (a) of the mobile device (12) with respect to the display device (14).

Device according to one of the preceding claims, in which the location-variant position image (22; 28a-e) has dimensions along a first display direction (x) and a second display direction (y) of the display device (14), which as a dimension of the mobile device (12) along the first (x) and second (y) display directions such that the location-variant position image (22; 28a-e) is viewed by the mobile device (12) to a viewer of the display device (14) is at least partially obscured by the mobile device (12) when the mobile device is positioned relative to the display device (14).

Apparatus according to any of the preceding claims, wherein the receiving device (16) is adapted to receive an orientation signal (43) from the mobile device (12) having global orientation information of the mobile device (12), and wherein the computing device (18) is configured to determine an orientation (a) of the mobile device (12) with respect to the display device (14) based on the global orientation of the mobile device (12). A device according to any one of the preceding claims, wherein the computing device (18) is further adapted to determine an initial position (x ₀ , y ₀ ) of the mobile device (12) and the position (y ^ y of the mobile device (12) if the initial position (x ₀ , y ₀ ) is determined, the display device (14) being designed to determine the initial position (x ₀ , y ₀ ) for determining the initial position (x ₀ , y ₀ ), to obtain a location-variable initialization image (46a-c). receiving means (16) adapted to receive the received signal (26) from the mobile device (12) containing color information relating to the initial color of the location variants detected by the mobile device (12) And wherein the computing device (18) is adapted to evaluate the receive signal (26) to the display device (14) with respect to a location (χ ', y') at which the location variable e initialization image (46a-c) is displayed, and to determine, based on the received initial color information, the initial position (x ₀ , y ₀ ) of the mobile device (12) relative to the display device (14).

Device for determining an initial position of a mobile device with the following features: a display device (14) adapted to display a location-variable initialization image (46a-c) having an initial color; a receiving device (16), which is configured to receive a received signal (26) from the mobile device (12) having color information regarding the initial color of the location-variant initialization image (46a-c) detected by the mobile device (12) ; a calculation device (18) which is designed to evaluate the received signal (26), which is further configured to make the display device (14) sensitive to a location (χ ', y') at which the location-variant initialization image (46a-c) is displayed, and to determine based on the received initial color information, the initial position (y ₀ , yo) of the mobile device (12) with respect to the display device (14).

Apparatus according to claim 12, wherein said location-variant initialization image (46a-b) comprises a beam structure.

Apparatus according to claim 12 or 13, wherein the calculating means (18) is adapted to drive the display device (14) to have a first (46a) and a second (46b) location-varying one to determine the initial position (y ₀ , yo) Initialization image (46a) is spatially varying with respect to a first display direction (x) along a display surface of the display device (14), and wherein the second spatially variant initialization image (46b) is relative to a second display direction (y) along the display surface of the display device (46). 14) is spatially variable, wherein the calculation device (18) is designed to evaluate the received signal (26), so that a first color information relating to the first spatially variant initialization image (46a) is obtained and to evaluate the received signal, so that a second color information with respect of the second location-variant initialization image (46b) he and to determine the initial position (x ₀ , y ₀ ) of the mobile device (12) based on the first color information regarding the first display direction (x) and based on the second color information on the second display direction (y).

Apparatus according to claim 14, wherein the computing device (18) is adapted to drive the display device (14) such that the first location-variant initialization image (46a) has a first initial color information and wherein the second location-variant initialization image (46b) has a second initial color information.

16. The apparatus of claim 15, wherein the computing device is configured to drive the display device to display the first location-variant initialization image during a first time interval and to display the second location-variant initialization image during a second time interval overlap first time interval and the second time interval at least partially.

17. The device according to claim 14, wherein the calculation device (18) is designed to control the display device (14) so that the first location-variant initialization image (46a) and the second location-variant initialization image (46b) have a same initial color.

18. The apparatus of claim 17, wherein the computing device is configured to control the display device to display the first location-variant initialization image during a first time interval and to display the second spatially-variable initialization image (46b, 46b). 46a) during a second time interval, the second time interval following the first time interval.

19. An apparatus according to any one of claims 12-18, further adapted to determine a position (x ^ of the mobile device (12) after the initial position (x ₀ , y ₀ ) is determined, wherein for determining the position (x, y) the display device (14) is adapted to display a location-varying position image (22; 28a-e) having a color; the receiving device (16) is adapted to receive the received signal (26) from the mobile device (16); 12) having color information regarding the color of the location-variant position image (22; 28a-e) detected by the mobile device (12), and wherein the calculation device (18) is adapted to evaluate the reception signal (26) control the display device (14) with respect to a location at which the location-variant position image (22; 28a-e) is displayed, based on the evaluation of the received signal (26), and based on the received color information formation to determine the position (xt, y of the mobile device (12) with respect to the display device (14).

A system (60) comprising: a device (10, 30, 40) according to any one of the preceding claims; and a mobile device (12) configured to at least partially detect (34) an object area displayed by the display device (14); wherein the mobile device (12) is further configured to determine the color information based on the color of the detected location-variant position image (22; 28a-e) in the detected object area; and wherein the mobile device (12) is further adapted to transmit the received signal (26) with the color information.

The system of claim 20, wherein the mobile device (12) is adapted to determine a color distribution within the object area and to transmit the received signal (26) having the color information based on the determined color distribution.

22. Method for determining a position (x _{1 t} y of a mobile device (12) with the following steps:

Displaying a location-variant position image (22; 28a-e) having a color with a display device (14);

Receiving from the mobile device (12) a received signal (26) having color information relating to the color of the location-variant position image (22; 28a-e) detected by the mobile device (12);

Evaluating the received signal (26); and

Controlling the display device (14) with respect to a location (i, y-,) at which the location-variant position image (22; 28a-e) is displayed on the evaluation of the received signal (26); Determining the position (x ^ y of the mobile device (12) relative to the display device (14) based on the received color information of the received received signal (26).

Method for determining an initial position (x ₀ , y ₀ ) of a mobile device (12), comprising the following steps:

Displaying a location-variant initialization image (46a, 46b) having a color with a display device (14);

Receiving from the mobile device (12) a received signal (26) having a color infor- mation regarding the color of the location-variant initialization image (46a, 46b) detected by the mobile device (12);

Evaluating the received signal (26); and

Controlling the display device (14) with respect to a location at which the location-variant initialization image (46a, 46b) is displayed;

Determining the initial position (x ₀ , y ₀ ) of the mobile device (12) with respect to the display device (14) based on the received color information of the received received signal (26).

A method according to claim 22 or 23, further comprising the step of:

Positioning the mobile device so that the mobile device detects an object area (34) displayed by the display device (14) at least in part.

A method according to any one of claims 22-24, further comprising the steps of:

Detecting at least a portion (34) of an object area displayed by the display device (14);

Determining the color information based on at least one color in the detected object area (34); and Sending the received signal (26) with the color information.

A computer program comprising program code for performing the method of any of claims 22-25 when the program is run on a computer.