WO2010040384A1

WO2010040384A1 - Navigation apparatus having a three-dimensional display

Info

Publication number: WO2010040384A1
Application number: PCT/EP2008/063391
Authority: WO
Inventors: Peter Van Hulten; Roland Van Venrooy
Original assignee: TomTom International BV
Current assignee: TomTom International BV
Priority date: 2008-10-07
Filing date: 2008-10-07
Publication date: 2010-04-15
Anticipated expiration: 2011-04-07
Also published as: TW201017103A

Abstract

A navigation apparatus (200) comprises a display device (206) arranged to provide an autostereoscopic three-dimensional display and a processor (202) arranged to control the display device (206); and the processor is arranged to determine a visual depth of a graphical object and to control the display device to display the graphical object at the visual depth.

Description

NAVIGATION APPARATUS HAVING A THREE-DIMENSIONAL DISPLAY

Field of the Invention

The present invention relates to a navigation apparatus of the type that displays navigation information to a user. The present invention also relates to a method of displaying information to a user of a navigation apparatus.

Background to the Invention

Portable computing devices, for example Portable Navigation Devices (PNDs) that include GPS (Global Positioning System) signal reception and processing functionality are well known and are widely employed as in-car or other vehicle navigation systems.

In general terms, a modern PND comprises a processor, memory (at least one of volatile and non-volatile, and commonly both), and map data stored within said memory. The processor and memory cooperate to provide an execution environment in which a software operating system may be established, and additionally it is commonplace for one or more additional software programs to be provided to enable the functionality of the PND to be controlled, and to provide various other functions.

Typically these devices further comprise one or more input interfaces that allow a user to interact with and control the device, and one or more output interfaces by means of which information may be relayed to the user. Illustrative examples of output interfaces include a visual display and a speaker for audible output. Illustrative examples of input interfaces include one or more physical buttons to control on/off operation or other features of the device (which buttons need not necessarily be on the device itself but could be on a steering wheel if the device is built into a vehicle), and a microphone for detecting user speech. In one particular arrangement, the output interface display may be configured as a touch sensitive display (by means of a touch sensitive overlay or otherwise) additionally to provide an input interface by means of which a user can operate the device by touch. Devices of this type will also often include one or more physical connector interfaces by means of which power and optionally data signals can be transmitted to and received from the device, and optionally one or more wireless transmitters/receivers to allow communication over cellular telecommunications and other signal and data networks, for example Bluetooth, Wi-Fi, Wi-Max, GSM, UMTS and the like. PNDs of this type also include a GPS antenna by means of which satellite- broadcast signals, including location data, can be received and subsequently processed to determine a current location of the device.

The PND may also include electronic gyroscopes and accelerometers which produce signals that can be processed to determine the current angular and linear acceleration, and in turn, and in conjunction with location information derived from the GPS signal, velocity and relative displacement of the device and thus the vehicle in which it is mounted. Typically, such features are most commonly provided in in-vehicle navigation systems, but may also be provided in PNDs if it is expedient to do so.

The utility of such PNDs is manifested primarily in their ability to determine a route between a first location (typically a start or current location) and a second location (typically a destination). These locations can be input by a user of the device, by any of a wide variety of different methods, for example by postcode, street name and house number, previously stored "well known" destinations (such as famous locations, municipal locations (such as sports grounds or swimming baths) or other points of interest), and favourite or recently visited destinations. Typically, the PND is enabled by software for computing a "best" or "optimum" route between the start and destination address locations from the map data. A "best" or "optimum" route is determined on the basis of predetermined criteria and need not necessarily be the fastest or shortest route. The selection of the route along which to guide the driver can be very sophisticated, and the selected route may take into account existing, predicted and dynamically and/or wirelessly received traffic and road information, historical information about road speeds, and the driver's own preferences for the factors determining road choice (for example the driver may specify that the route should not include motorways or toll roads).

In addition, the device may continually monitor road and traffic conditions, and offer to or choose to change the route over which the remainder of the journey is to be made due to changed conditions. Real time traffic monitoring systems, based on various technologies (e.g. mobile phone data exchanges, fixed cameras, GPS fleet tracking) are being used to identify traffic delays and to feed the information into notification systems.

PNDs of this type may typically be mounted on the dashboard or windscreen of a vehicle, but may also be formed as part of an on-board computer of the vehicle radio or indeed as part of the control system of the vehicle itself. The navigation device may also be part of a hand-held system, such as a PDA (Portable Digital Assistant), a media player, a mobile phone or the like, and in these cases, the normal functionality of the hand-held system is extended by means of the installation of software on the device to perform both route calculation and navigation along a calculated route.

Route planning and navigation functionality may also be provided by a desktop or mobile computing resource running appropriate software. For example, the Royal Automobile Club (RAC) provides an on-line route planning and navigation facility at http://www.rac.co.uk, which facility allows a user to enter a start point and a destination whereupon the server with which the user's computing resource is communicating calculates a route (aspects of which may be user specified), generates a map, and generates a set of exhaustive navigation instructions for guiding the user from the selected start point to the selected destination. The facility also provides for pseudo three-dimensional rendering of a calculated route, and route preview functionality which simulates a user travelling along the route and thereby provides the user with a preview of the calculated route.

In the context of a PND, once a route has been calculated, the user interacts with the navigation device to select the desired calculated route, optionally from a list of proposed routes. Optionally, the user may intervene in, or guide the route selection process, for example by specifying that certain routes, roads, locations or criteria are to be avoided or are mandatory for a particular journey. The route calculation aspect of the PND forms one primary function, and navigation along such a route is another primary function.

During navigation along a calculated route, it is usual for such PNDs to provide visual and/or audible instructions to guide the user along a chosen route to the end of that route, i.e. the desired destination. It is also usual for PNDs to display map information on-screen during the navigation, such information regularly being updated on-screen so that the map information displayed is representative of the current location of the device, and thus of the user or user's vehicle if the device is being used for in- vehicle navigation. An icon displayed on-screen typically denotes the current device location, and is centred with the map information of current and surrounding roads in the vicinity of the current device location and other map features also being displayed. Additionally, navigation information may be displayed, optionally in a status bar above, below or to one side of the displayed map information, examples of navigation information include a distance to the next deviation from the current road required to be taken by the user, the nature of that deviation possibly being represented by a further icon suggestive of the particular type of deviation, for example a left or right turn. The navigation function also determines the content, duration and timing of audible instructions by means of which the user can be guided along the route. As can be appreciated a simple instruction such as "turn left in 100 m" requires significant processing and analysis. As previously mentioned, user interaction with the device may be by a touch screen, or additionally or alternately by steering column mounted remote control, by voice activation or by any other suitable method.

A further important function provided by the device is automatic route recalculation in the event that: a user deviates from the previously calculated route during navigation (either by accident or intentionally); real-time traffic conditions dictate that an alternative route would be more expedient and the device is suitably enabled to recognize such conditions automatically, or if a user actively causes the device to perform route re-calculation for any reason.

It is also known to allow a route to be calculated with user defined criteria; for example, the user may prefer a scenic route to be calculated by the device, or may wish to avoid any roads on which traffic congestion is likely, expected or currently prevailing. The device software would then calculate various routes and weigh more favourably those that include along their route the highest number of points of interest (known as POIs) tagged as being for example of scenic beauty, or, using stored information indicative of prevailing traffic conditions on particular roads, order the calculated routes in terms of a level of likely congestion or delay on account thereof. Other POI-based and traffic information-based route calculation and navigation criteria are also possible.

Although the route calculation and navigation functions are fundamental to the overall utility of PNDs, it is possible to use the device purely for information display, or "free-driving", in which only map information relevant to the current device location is displayed, and in which no route has been calculated and no navigation is currently being performed by the device. Such a mode of operation is often applicable when the user already knows the route along which it is desired to travel and does not require navigation assistance. Devices of the type described above, for example the 920T model manufactured and supplied by TomTom International B. V., provide a reliable means for enabling users to navigate from one position to another. Such devices are of great utility when the user is not familiar with the route to the destination to which they are navigating.

As mentioned above, the memory of the PND stores map data used by the PND not only to calculate routes and provide necessary navigation instructions to users, but also to provide visual information to users through the visual display of the PND.

However, since the display of a PND is relatively small in size, it is difficult for a user to clearly and quickly see displayed information. For example, when a PND displays information representing an upcoming area of a route to the user, it is difficult for the user to quickly appreciate the displayed information. This can cause the user danger when they are driving a vehicle and can be inconvenient and the very least. Summary of the Invention

According to a first aspect of the present invention, there is provided a navigation apparatus comprising a display device (206); and a processor (202) arranged to control the display device (206); characterised in that the display device (206) is arranged to provide an autostereoscopic three-dimensional display; and the processor is arranged to determine a visual depth of a graphical object and to control the display device to display the graphical object at the visual depth.

According to a second aspect of the present invention, there is provided a method of displaying information to a user of a navigation apparatus, having an autostereoscopic display device (206), characterised by: determining a visual depth of a graphical object; and controlling the display device (206) to display the graphical object at the first visual depths.

It is thus possible to provide an apparatus and method capable of displaying navigation information at one or more visual depths on a display device. Consequently, user experience is enhanced, because visual depth may be utilised to improve the appearance, for example making navigation information more easily understandable, by the application of visual depth.

Brief Description of the Drawings

At least one embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a schematic illustration of an exemplary part of a Global Positioning System (GPS) usable by a navigation device; Figure 2 is a schematic diagram of a communications system for communication between a navigation device and a server;

Figure 3 is a schematic illustration of electronic components of the navigation device of Figure 2 or any other suitable navigation device;

Figure 4 is a schematic diagram of an arrangement of mounting and/or docking a navigation device;

Figure 5 is a schematic representation of an architectural stack employed by the navigation device of Figure 3;

Figure 6 is a representation of an autostereoscopic display device displaying thereon first and second visual display screens according to embodiments of the present invention; and

Figure 7 is a representation of navigational instructions displayed at a visual depth corresponding to an order in which they are to be executed by a user according to embodiments of the present invention.

Detailed Description of Preferred Embodiments Throughout the following description identical reference numerals will be used to identify like parts.

Embodiments of the present invention will now be described with particular reference to a PND. It should be remembered, however, that the teachings of the present invention are not limited to PNDs but are instead universally applicable to any type of processing device that is configured to execute navigation software in a portable manner so as to provide route planning and navigation functionality. It follows therefore that in the context of the present application, a navigation device is intended to include (without limitation) any type of route planning and navigation device, irrespective of whether that device is embodied as a PND, a vehicle such as an automobile, or indeed a portable computing resource, for example a portable personal computer (PC), a mobile telephone or a Personal Digital Assistant (PDA) executing route planning and navigation software.

It will also be apparent from the following that the teachings of the present invention even have utility in circumstances, where a user is not seeking instructions on how to navigate from one point to another, but merely wishes to be provided with a view of a given location. In such circumstances the "destination" location selected by the user need not have a corresponding start location from which the user wishes to start navigating, and as a consequence references herein to the "destination" location or indeed to a "destination" view should not be interpreted to mean that the generation of a route is essential, that travelling to the "destination" must occur, or indeed that the presence of a destination requires the designation of a corresponding start location.

With the above provisos in mind, the Global Positioning System (GPS) of Figure 1 and the like are used for a variety of purposes. In general, the GPS is a satellite-radio based navigation system capable of determining continuous position, velocity, time, and in some instances direction information for an unlimited number of users. Formerly known as NAVSTAR, the GPS incorporates a plurality of satellites which orbit the earth in extremely precise orbits. Based on these precise orbits, GPS satellites can relay their location to any number of receiving units.

The GPS system is implemented when a device, specially equipped to receive GPS data, begins scanning radio frequencies for GPS satellite signals. Upon receiving a radio signal from a GPS satellite, the device determines the precise location of that satellite via one of a plurality of different conventional methods. The device will continue scanning, in most instances, for signals until it has acquired at least three different satellite signals (noting that position is not normally, but can be determined, with only two signals using other triangulation techniques). Implementing geometric triangulation, the receiver utilizes the three known positions to determine its own two-dimensional position relative to the satellites. This can be done in a known manner. Additionally, acquiring a fourth satellite signal allows the receiving device to calculate its three dimensional position by the same geometrical calculation in a known manner. The position and velocity data can be updated in real time on a continuous basis by an unlimited number of users.

As shown in Figure 1 , the GPS system 100 comprises a plurality of satellites 102 orbiting about the earth 104. A GPS receiver 106 receives spread spectrum GPS satellite data signals 108 from a number of the plurality of satellites 102. The spread spectrum data signals 108 are continuously transmitted from each satellite 102, the spread spectrum data signals 108 transmitted each comprise a data stream including information identifying a particular satellite 102 from which the data stream originates. The GPS receiver 106 generally requires spread spectrum data signals 108 from at least three satellites 102 in order to be able to calculate a two-dimensional position. Receipt of a fourth spread spectrum data signal enables the GPS receiver 106 to calculate, using a known technique, a three-dimensional position.

Turning to Figure 2, a navigation device 200 comprising or coupled to the GPS receiver device 106, is capable of establishing a data session, if required, with network hardware of a "mobile" or telecommunications network via a mobile device (not shown), for example a mobile telephone, PDA, and/or any device with mobile telephone technology, in order to establish a digital connection, for example a digital connection via known Bluetooth technology. Thereafter, through its network service provider, the mobile device can establish a network connection (through the Internet for example) with a server 150. As such, a "mobile" network connection can be established between the navigation device 200 (which can be, and often times is, mobile as it travels alone and/or in a vehicle) and the server 150 to provide a "real-time" or at least very "up to date" gateway for information.

The establishing of the network connection between the mobile device (via a service provider) and another device such as the server 150, using the Internet for example, can be done in a known manner. In this respect, any number of appropriate data communications protocols can be employed, for example the TCP/IP layered protocol. Furthermore, the mobile device can utilize any number of communication standards such as CDMA2000, GSM, IEEE 802.1 1 a/b/c/g/n, etc.

Hence, it can be seen that the internet connection may be utilised, which can be achieved via data connection, via a mobile phone or mobile phone technology within the navigation device 200 for example. Although not shown, the navigation device 200 may, of course, include its own mobile telephone technology within the navigation device 200 itself (including an antenna for example, or optionally using the internal antenna of the navigation device 200). The mobile phone technology within the navigation device 200 can include internal components, and/or can include an insertable card (e.g. Subscriber Identity Module (SIM) card), complete with necessary mobile phone technology and/or an antenna for example. As such, mobile phone technology within the navigation device 200 can similarly establish a network connection between the navigation device 200 and the server 150, via the Internet for example, in a manner similar to that of any mobile device. For telephone settings, a Bluetooth enabled navigation device may be used to work correctly with the ever changing spectrum of mobile phone models, manufacturers, etc., model/manufacturer specific settings may be stored on the navigation device 200 for example. The data stored for this information can be updated.

In Figure 2, the navigation device 200 is depicted as being in communication with the server 150 via a generic communications channel 152 that can be implemented by any of a number of different arrangements. The communication channel 152 generically represents the propagating medium or path that connects the navigation device 200 and the server 150. The server 150 and the navigation device 200 can communicate when a connection via the communications channel 152 is established between the server 150 and the navigation device 200 (noting that such a connection can be a data connection via mobile device, a direct connection via personal computer via the internet, etc.).

The communication channel 152 is not limited to a particular communication technology. Additionally, the communication channel 152 is not limited to a single communication technology; that is, the channel 152 may include several communication links that use a variety of technology. For example, the communication channel 152 can be adapted to provide a path for electrical, optical, and/or electromagnetic communications, etc. As such, the communication channel 152 includes, but is not limited to, one or a combination of the following: electric circuits, electrical conductors such as wires and coaxial cables, fibre optic cables, converters, radio-frequency (RF) waves, the atmosphere, free space, etc. Furthermore, the communication channel 152 can include intermediate devices such as routers, repeaters, buffers, transmitters, and receivers, for example.

In one illustrative arrangement, the communication channel 152 includes telephone and computer networks. Furthermore, the communication channel 152 may be capable of accommodating wireless communication, for example, infrared communications, radio frequency communications, such as microwave frequency communications, etc. Additionally, the communication channel 152 can accommodate satellite communication.

The communication signals transmitted through the communication channel 152 include, but are not limited to, signals as may be required or desired for given communication technology. For example, the signals may be adapted to be used in cellular communication technology such as Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Code Division Multiple Access (CDMA), Global System for Mobile Communications (GSM), etc. Both digital and analogue signals can be transmitted through the communication channel 152. These signals may be modulated, encrypted and/or compressed signals as may be desirable for the communication technology.

The server 150 includes, in addition to other components which may not be illustrated, a processor 154 operatively connected to a memory 156 and further operatively connected, via a wired or wireless connection 158, to a mass data storage device 160. The mass storage device 160 contains a store of navigation data and map information, and can again be a separate device from the server 150 or can be incorporated into the server 150. The processor 154 is further operatively connected to transmitter 162 and receiver 164, to transmit and receive information to and from navigation device 200 via communications channel 152. The signals sent and received may include data, communication, and/or other propagated signals. The transmitter 162 and receiver 164 may be selected or designed according to the communications requirement and communication technology used in the communication design for the navigation system 200. Further, it should be noted that the functions of transmitter 162 and receiver 164 may be combined into a single transceiver. As mentioned above, the navigation device 200 can be arranged to communicate with the server 150 through communications channel 152, using transmitter 166 and receiver 168 to send and receive signals and/or data through the communications channel 152, noting that these devices can further be used to communicate with devices other than server 150. Further, the transmitter 166 and receiver 168 are selected or designed according to communication requirements and communication technology used in the communication design for the navigation device 200 and the functions of the transmitter 166 and receiver 168 may be combined into a single transceiver as described above in relation to Figure 2. Of course, the navigation device 200 comprises other hardware and/or functional parts, which will be described later herein in further detail. Software stored in server memory 156 provides instructions for the processor

154 and allows the server 150 to provide services to the navigation device 200. One service provided by the server 150 involves processing requests from the navigation device 200 and transmitting navigation data from the mass data storage 160 to the navigation device 200. Another service that can be provided by the server 150 includes processing the navigation data using various algorithms for a desired application and sending the results of these calculations to the navigation device 200.

The server 150 constitutes a remote source of data accessible by the navigation device 200 via a wireless channel. The server 150 may include a network server located on a local area network (LAN), wide area network (WAN), virtual private network (VPN), etc.

The server 150 may include a personal computer such as a desktop or laptop computer, and the communication channel 152 may be a cable connected between the personal computer and the navigation device 200. Alternatively, a personal computer may be connected between the navigation device 200 and the server 150 to establish an internet connection between the server 150 and the navigation device 200.

The navigation device 200 may be provided with information from the server 150 via information downloads which may be periodically updated automatically or upon a user connecting the navigation device 200 to the server 150 and/or may be more dynamic upon a more constant or frequent connection being made between the server 150 and navigation device 200 via a wireless mobile connection device and TCP/IP connection for example. For many dynamic calculations, the processor 154 in the server 150 may be used to handle the bulk of processing needs, however, a processor (not shown in Figure 2) of the navigation device 200 can also handle much processing and calculation, oftentimes independent of a connection to a server 150. Referring to Figure 3, it should be noted that the block diagram of the navigation device 200 is not inclusive of all components of the navigation device, but is only representative of many example components. The navigation device 200 is located within a housing (not shown). The navigation device 200 includes a processing resource comprising, for example, the processor 202 mentioned above, the processor 202 being coupled to an input device 204 and a display device, for example a display screen 206. Although reference is made here to the input device 204 in the singular, the skilled person should appreciate that the input device 204 represents any number of input devices, including a keyboard device, voice input device, touch panel and/or any other known input device utilised to input information. Likewise, the display screen 206 can include any type of display screen such as a Liquid Crystal Display (LCD), for example. In one arrangement, one aspect of the input device 204, the touch panel, and the display screen 206 are integrated so as to provide an integrated input and display device, including a touchpad or touchscreen input 250 (Figure 4) to enable both input of information (via direct input, menu selection, etc.) and display of information through the touch panel screen so that a user need only touch a portion of the display screen 206 to select one of a plurality of display choices or to activate one of a plurality of virtual or "soft" buttons. In this respect, the processor 202 supports a Graphical User Interface (GUI) that operates in conjunction with the touchscreen.

In the navigation device 200, the processor 202 is operatively connected to and capable of receiving input information from input device 204 via a connection 210, and operatively connected to at least one of the display screen 206 and the output device 208, via respective output connections 212, to output information thereto. The navigation device 200 may include an output device 208, for example an audible output device (e.g. a loudspeaker). As the output device 208 can produce audible information for a user of the navigation device 200, it is should equally be understood that input device 204 can include a microphone and software for receiving input voice commands as well. Further, the navigation device 200 can also include any additional input device

204 and/or any additional output device, such as audio input/output devices for example.

The processor 202 is operatively connected to memory 214 via connection 216 and is further adapted to receive/send information from/to input/output (I/O) ports 218 via connection 220, wherein the I/O port 218 is connectible to an I/O device 222 external to the navigation device 200. The external I/O device 222 may include, but is not limited to an external listening device, such as an earpiece for example. The connection to I/O device 222 can further be a wired or wireless connection to any other external device such as a car stereo unit for hands-free operation and/or for voice activated operation for example, for connection to an earpiece or headphones, and/or for connection to a mobile telephone for example, wherein the mobile telephone connection can be used to establish a data connection between the navigation device 200 and the Internet or any other network for example, and/or to establish a connection to a server via the Internet or some other network for example. Figure 3 further illustrates an operative connection between the processor 202 and an antenna/receiver 224 via connection 226, wherein the antenna/receiver 224 can be a GPS antenna/receiver for example. It should be understood that the antenna and receiver designated by reference numeral 224 are combined schematically for illustration, but that the antenna and receiver may be separately located components, and that the antenna may be a GPS patch antenna or helical antenna for example. It will, of course, be understood by one of ordinary skill in the art that the electronic components shown in Figure 3 are powered by one or more power sources (not shown) in a conventional manner. As will be understood by one of ordinary skill in the art, different configurations of the components shown in Figure 3 are contemplated. For example, the components shown in Figure 3 may be in communication with one another via wired and/or wireless connections and the like. Thus, the navigation device 200 described herein can be a portable or handheld navigation device 200.

In addition, the portable or handheld navigation device 200 of Figure 3 can be connected or "docked" in a known manner to a vehicle such as a bicycle, a motorbike, a car or a boat for example. Such a navigation device 200 is then removable from the docked location for portable or handheld navigation use.

Referring to Figure 4, the navigation device 200 may be a unit that includes the integrated input and display device 206 and the other components of Figure 2 (including, but not limited to, the internal GPS receiver 224, the microprocessor 202, a power supply (not shown), memory systems 214, etc.). The navigation device 200 may sit on an arm 252, which itself may be secured to a vehicle dashboard/window/etc, using a suction cup 254. This arm 252 is one example of a docking station to which the navigation device 200 can be docked. The navigation device 200 can be docked or otherwise connected to the arm 252 of the docking station by snap connecting the navigation device 200 to the arm 252 for example. The navigation device 200 may then be rotatable on the arm 252. To release the connection between the navigation device 200 and the docking station, a button (not shown) on the navigation device 200 may be pressed, for example. Other equally suitable arrangements for coupling and decoupling the navigation device 200 to a docking station are well known to persons of ordinary skill in the art. Turning to Figure 5, the processor 202 and memory 214 cooperate to support a

BIOS (Basic Input/Output System) 282 that functions as an interface between functional hardware components 280 of the navigation device 200 and the software executed by the device. The processor 202 then loads an operating system 284 from the memory 214, which provides an environment in which application software 286 (implementing some or all of the above described route planning and navigation functionality) can run. The application software 286 provides an operational environment including the GUI that supports core functions of the navigation device, for example map viewing, route planning, navigation functions and any other functions associated therewith. In this respect, part of the application software 286 comprises an autostereoscopic view module 288. Embodiments of the present invention comprise a display device 206 having autostereoscopic properties. That is, the display device 206 which outputs a three- dimensional display to a user without a need for the user to wear specially adapted glasses or the like.

The display device 206 comprises a layer of lenticules, transparent cylindrical lenses, mounted on a surface of the display, such as an LCD device. The lenses are arranged in such a way that an image plane of the display is at a focal plane of the lenses. A viewer's eye then sees a portion of the display under each lens, whilst the other eye observes a portion of the display that is off-centre under each lens. In this way, each eye sees a different area of pixels under each lens and, when different views are displayed by the plurality of areas under each lens, an autostereoscopic view is produced by the display device 206. The autostereoscopic view enables displayed images to have an appearance of depth. Thus, parts of an image can be displayed at a lower depth, thus appearing closer to the viewer, than other parts which are given greater depth. In operation, items displayed on the display are associated with depth information which indicates a depth at which each item is to be displayed.

Some embodiments of the present invention provide different information for viewers located in different positions with respect to the display device 206. The different views are used, in some embodiments of the present invention, to provide users with different information with respect to a user's viewing position in relation to the navigation apparatus 200.

By appropriately arranging the lenticules on the display device 206, the display device 206 can be configured to provide a first display to a first viewer located in a first viewing position, a second display to a second viewer in a second viewing position, and so on. In some embodiments of the present invention, different views are utilised to provide a driver with first navigational information and a passenger with second navigation information. Embodiments may also provide other passengers, such as rear- set passengers, with a third display containing, for example, entertainment-related information.

For example, first navigation information provided to a driver may comprise minimum information necessary to navigate to a destination in order that the driver is not presented with unnecessary information, whilst a passenger may be presented with different information, such as further information regarding optional routes, traffic information etc. Rear-seat passengers may meanwhile be presented with entertainment-information, such as information obtained from news-services and/or information related to the journey such as time-of-arrival etc. Figure 6 shows an example of display device 206 of embodiments of the present invention. The display device 206 is arranged to provide a first display 601 containing information necessary for the driver to navigate a route and a second display 620 containing non-essential navigation information, such as traffic related information, which is arranged to be visible by a passenger seated alongside the driver by appropriate arrangement of lenticules and display of information by display device 206, as described above. Additionally, display device 206 may be arranged to display one or more further displays screens to persons seated in other positions, such as in rear seats of a vehicle. The further displays may be additional representations of the first and second displays 610, 620 or may display different information. In some embodiments, the autostereoscopic display device 206 is arranged to provide first and second different displays to a single user. In particular, the display device 206 is utilised to provide a driver with first and second views. In the first view which is arranged to be provided to the driver when in a normal driving position, navigation information and map data is provided. However, the second display is arranged, by appropriate configuration of lenticules, to be provided to the driver in a slightly different viewing position. For example, the driver may be required to move his or her head by a relatively small amount such that the second display is visible. The second display may provide other information to the driver. In some embodiments, the navigation apparatus 200 is connected to a video camera arranged at a rear of the vehicle. In these embodiments, when the driver views the second display an image from the rear of the vehicle is visible to the driver as a parking aid.

In some embodiments of the present invention, the autostereoscopic display device 206 is utilised to draw a viewer's attention to specific visual objects. Attention is drawn to specific visual objects by presenting those objects at a lower depth, thus closer to the user, than other objects, such as map data. In other words, the perception of depth may be utilised to display important visual objects which require a user's attention forward of other information or visual objects. Depth information associated with important objects or information which is required to be quickly perceived by a user indicates that the object is to be displayed at a lower depth than other less important information. It is envisaged that one or more of emergency information, such as a window or pop-up providing emergency information, may be displayed at a lower depth, thus appearing closer to the user, than other information or visual objects deemed less important. Similarly, navigation guidance may be displayed at a lower depth than a map display. In this way, a user may be more likely to obtain guidance information with a short glance at the display device 206. In some embodiments, a map may be displayed at a depth which is lower than that of the surface of display device 206 in order to provide a view which reduces eye strain of a user.

In some embodiments of the present invention, depth-perception provided by the display device 206 is utilised to provide a more realistic display of geographical features. For example, a building which is further away from the user is displayed having a greater depth on display device 206 than another building which is closer to a current location of the navigation device 200. That is, a depth at which a geographical feature is displayed on display device 206 is related to a distance of that geographical object from the current location of the navigation device 200. The depth may be proportional to the distance in some embodiments. In some embodiments of the present invention, depth information is utilised to provide an indication of a speed at which a user is driving. In order to provide an indication of speed, in some embodiments a horizon of a map displayed on the display device is displayed at a depth related to a speed of travel. That is, as the speed of travel increases, the depth of the horizon increases providing a visual indication of speed. Geographical items displayed on the map may also vary in depth in relation to the horizon to provide a realistic map view.

In some embodiments, navigation information, such as direction, lane change information etc., is displayed to a user on the display device 206 at a depth which is related to a required time for that information. That is, for navigation information a display depth corresponds a time at which the navigation information is required. For example, referring to Figure 7, three items of navigation information are shown 710, 720, 730 each indicating an instruction to a user. In the example, the navigation item 710 indicates to go straight ahead, the second 720 to turn right, and the third to go straight ahead again. The three navigation items 710, 720, 730 are displayed for use by a user in chronological order. That is, the first navigation item 710 is required to be performed first, the second 720 second, and so on. To indicate the chronological order to the user and to provide them with advance notice of future navigational instructions, the three items 710, 720, 73 are simultaneously displayed. However each has a depth relating to its order in the sequence. In other words, the first item 710 is displayed at a lower depth than the second item 720, whilst the third item 730 is displayed at a lower depth than the second item 720. Thus the user may see all three items 710, 720, 730 and be able to have advance notice of navigation instructions, but also it is easier to perceive immediately upcoming navigation items 710. As the navigational instructions are performed, they may appear to move toward the user in direction of arrow 740. In some embodiments, the first navigation item 710 may be displayed at a depth which is projected in front of the screen 260, making it easily appreciated by the user. It will be realised that fewer or more than three navigational items may be displayed to the user.

In some embodiments, depth information is used to enhance a visual appeal of a graphical user interface (GUI) of the navigation device 200. In embodiments of the invention, user controls, such as buttons, sliders and the like are displayed on the display device 206 at a different depth to other information, such as map data. A control plane having a predetermined may be utilised upon which user controls are displayed. This more easily enables users to discern controls which are to be operated from other displayed information. The control pane may be displayed at a surface of the display screen 206 in front of map information. Furthermore, in some embodiments, user controls are displayed at a first depth and, when operated by a user, are moved to a second depth. For example, a button may be displayed at a first depth on the display device. However when pressed by a user the button is moved to be displayed at a second depth to indicate the user pressing on the button using the touch sensitive screen. In some embodiments, the display of information on the autostereoscopic display device 206 having depth perception is utilised in combination with 3D audio effects. In particular, in some embodiments, 3D audio effects are utilised to place or project sounds generated by audio output device 208 at a location in three dimensional space to assist in directing the user to an appropriate source of information. For example, when a navigational instruction is provided by the navigation device 200 instructing a user to turn right an accompanying sound effect may be projected to a right hand side of the navigation device 200, thus assisting the user with navigation. In a further example, 3D audio effects may be utilised to warn the user by directing them to a source of warning information, such as by outputting a warning sound projected in front of an instrument dial when a predetermined speed is exceeded, thus directing the user to view a speed instrument dial of a vehicle.

Embodiments of the present invention improve a display of information to a user of a navigation device by the application of visual depth to displayed information.

It will also be appreciated that whilst various aspects and embodiments of the present invention have heretofore been described, the scope of the present invention is not limited to the particular arrangements set out herein and instead extends to encompass all arrangements, and modifications and alterations thereto, which fall within the scope of the appended claims.

Whilst embodiments described in the foregoing detailed description refer to GPS, it should be noted that the navigation device may utilise any kind of position sensing technology as an alternative to (or indeed in addition to) GPS. For example the navigation device may utilise using other global navigation satellite systems such as the European Galileo system. Equally, it is not limited to satellite based but could readily function using ground based beacons or any other kind of system that enables the device to determine its geographic location. Alternative embodiments of the invention can be implemented as a computer program product for use with a computer system, the computer program product being, for example, a series of computer instructions stored on a tangible data recording medium, such as a diskette, CD-ROM, ROM, or fixed disk, or embodied in a computer data signal, the signal being transmitted over a tangible medium or a wireless medium, for example, microwave or infrared. The series of computer instructions can constitute all or part of the functionality described above, and can also be stored in any memory device, volatile or non-volatile, such as semiconductor, magnetic, optical or other memory device.

It will also be well understood by persons of ordinary skill in the art that whilst the preferred embodiment implements certain functionality by means of software, that functionality could equally be implemented solely in hardware (for example by means of one or more ASICs (application specific integrated circuit)) or indeed by a mix of hardware and software. As such, the scope of the present invention should not be interpreted as being limited only to being implemented in software. Lastly, it should also be noted that whilst the accompanying claims set out particular combinations of features described herein, the scope of the present invention is not limited to the particular combinations hereafter claimed, but instead extends to encompass any combination of features or embodiments herein disclosed irrespective of whether or not that particular combination has been specifically enumerated in the accompanying claims at this time.

Claims

1. A navigation apparatus comprising: a display device (206); and a processor (202) arranged to control the display device (206); characterised in that the display device (206) is arranged to provide an autostereoscopic three-dimensional display; and the processor is arranged to determine a visual depth of a graphical object and to control the display device to display the graphical object at the visual depth.

2. The navigation apparatus of claim 1 , wherein the processor (202) (202) is arranged to control the display device (206) (206) to display first and second navigational instructions (710, 720), wherein the first navigational instruction (710) is displayed at a first visual depth and the second navigational instruction (720) is displayed at a second visual depth greater than the first visual depth corresponding to the order in which the navigational instructions (710, 720) are to be carried out by a user.

3. The navigation apparatus of claim 1 or 2, wherein the display device (206) is touch sensitive and the processor (202) is arranged to display on the display device (206) one or more controls operable by a user touching a corresponding portion of the display device (206) and, in response to the user operating a control the processor (202) is arranged to display the operated control at a greater visual depth whilst the user touches the corresponding portion of the display device (206).

4. The navigation apparatus of any preceding claim, wherein the processor (202) is arranged to display on the display device (206) a representation of map data corresponding to a surrounding location of the navigation apparatus, wherein the processor (202) is arranged to display map features at a visual depth corresponding to a distance of each map feature from a current location of the navigation apparatus.

5. The navigation apparatus of claim 4, wherein the processor (202) is arranged to vary a visual depth at which one or more map features are displayed according to a speed of the navigation apparatus.

6 The navigation apparatus of any preceding claim, comprising an audio output device (208), wherein the processor (202) is arranged to apply a three-dimensional audio effect to an output of the audio output device, such that the output of the audio device is perceived by a user to be projected to a location surrounding the navigation apparatus.

7. The navigation apparatus of claim 1 , wherein the processor (202) is arranged to control the display device (206) to provide first and second different display screens (610, 620) visible from first and second locations, respectively.

8. The navigation apparatus of claim 7, wherein the first display screen (610) is arranged to provide first navigation information and the second display screen (620) is arranged to provide second navigation information at least partly different from the first navigation information.

9. The navigation apparatus of claim 7, wherein the first display screen (610) comprises navigation information and the second display screen (620) comprises video data from a camera.

10. A method of displaying information to a user of a navigation apparatus, having an autostereoscopic display device (206), characterised by: determining a visual depth of a graphical object; and controlling the display device (206) to display the graphical object at the first visual depths.

1 1 . The method of claim 10, comprising: determining a visual depth of further graphical objects, wherein the graphical objects are representations of features in map data and the respective visual depth of each object is based upon a distance of that object from a current location of the navigation apparatus; and controlling the display device (206) to display the graphical objects at the respective visual depths.

12. The method of claim 1 1 , wherein the visual depths of each graphical object varies according to a speed of the navigation apparatus.

13. The method of claim 10, comprising: determining a plurality of navigational instructions (710,720) to be carried out by a user in an execution order; determining a visual depth corresponding to each of the navigational instructions (710, 720) according to the execution order; controlling the display device (206) to display the plurality of navigational instructions (710, 720) at the respective visual depths.

14. The method of claim 10, wherein the graphical object is a user control operable by the user touching a corresponding portion of the display device (206), the method comprising: determining when the user operates the user control; and controlling the display device (206) to display the user control at a second visual depth whilst the user operates the user control.

15. The method of claim 10, wherein the first graphical object forms part of a first display screen (610), and the method comprises: controlling the display device (206) to display a second display screen (620), different from the first display screen (610), wherein the second display screen (620) is visible from a different viewing position than the first display screen (620).