A storage part of an on-vehicle apparatus stores simplified map data of which content is simplified as compared to original map data used for route guidance. An image generator of the on-vehicle apparatus retrieves the simplified map data stored on the storage part and generates a map image based on the simplified map data. Then a transmitter of the on-vehicle apparatus transmits the map image generated by the image generator to a portable device, in response to a demand from the portable device.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a technology for transmitting data from an on-vehicle apparatus used for a vehicle.

2. Description of the Background Art

On-vehicle apparatuses, such as car navigation apparatus, used for vehicles to display maps have been conventionally known. There is a case where a driver cannot use a function of the on-vehicle apparatus such as route guidance while a fellow passenger other than the driver of the vehicle is looking at, for example, a map of an area around a current location of the vehicle or a map of an area through which the vehicle will go.

However, given convenience for both the diver and the fellow passenger, it is preferable that the fellow passenger can look at information such as a map without preventing the driver from using a function of the on-vehicle apparatus.

A technology that connects an on-vehicle apparatus to a portable device has been proposed as a technology that solves the problem. Such a technology connects the on-vehicle apparatus to the portable device by near field communication and transmits a map from the on-vehicle apparatus to the portable device if necessary. As a result, the map is displayed on a display of the portable device.

However, when the conventional technology is used, the map displayed on the on-vehicle apparatus is displayed on the portable device in a same style. The map is displayed on the portable device in the style designed to be looked at by a driver who is driving. Therefore, the map is not always preferable for the fellow passenger.

SUMMARY OF THE INVENTION

According to one aspect of the invention, an on-vehicle apparatus used in a vehicle includes: a storage part that stores first map data having a simplified content as compared to second map data used for route guidance; an image generator that generates a map image based on the first map data; and a transmitter that transmits the map image to a portable device in response to a demand from the portable device that is a communication partner of the on-vehicle apparatus.

Since the map image based on the first map data having the simplified content as compared to the second map data is transmitted to the portable device, a fellow passenger who carries the portable device can look at a more preferable map for him/her.

According to another aspect of the invention, the on-vehicle apparatus further includes: a receiver that receives from the portable device destination information specifying a destination of the vehicle; and a guidance part that executes the route guidance leading to the destination specified by the destination information.

The destination of the route guidance executed by the on-vehicle apparatus can be specified from the portable device.

According to another aspect of the invention, the on-vehicle apparatus further includes a data generator that generates the first map data based on the second map data.

Since the first map data is generated based on the second map data, there is no need to prepare the first map data separately from the second map data, and cost of the on-vehicle apparatus can be reduced.

Therefore, the object of this invention is to provide a preferable map for a fellow passenger to a portable device carried by the fellow passenger.

These and other objects, features, aspects and advantages of the invention will become more apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings.

DESCRIPTION OF THE EMBODIMENTS

1. Outline of on-Vehicle Apparatus

Referring to the accompanying drawings, an embodiment of an on-vehicle apparatus related to the invention is explained hereinbelow in detail. Prior to the detailed explanation of the embodiment, an outline of the on-vehicle apparatus is first explained referring toFIG. 1A.FIG. 1Aillustrates the outline of an on-vehicle apparatus7. The on-vehicle apparatus7is used on a vehicle8.

As shown inFIG. 1A, the on-vehicle apparatus7includes a simplified map database5that stores simplified map data2. The simplified map data2is map data generated by omitting a part of element data included in original map data1. The on-vehicle apparatus7transmits a map image generated based on the simplified map data2, to a portable device4that is a communication partner of the on-vehicle apparatus7.

The original map data1is map data (mainly vector data) used to generate the map image designed to be looked at by a driver while driving. The original map data1includes various element data, such as road data, facility data and icons image data, used for generating the map image. The original map data1is prepared on each of various scales. The map images on different scales can be displayed on a display3by using the original map data1, and comfortable route guidance can be provided to the driver.

However, the map image displayed on a display3of the on-vehicle apparatus7for the route guidance is not always displayed in a style easy for a fellow passenger to look at. In other words, the fellow passenger does not need, in many cases, a detailed map like a map used for the route guidance, and an easy-to-understand or enjoyable map is preferable for the fellow passenger.

In the on-vehicle apparatus7, the simplified map data2of which a content is simplified as compared to the original map data1used for the route guidance is stored beforehand in the simplified map database5(a step2). The on-vehicle apparatus7can provide an easy-to-understand or enjoyable map to the fellow passenger by generating the map image to be provided to the portable device4, based on the simplified map data2. Moreover, the simplified map data2is generated by omitting a part of the element data included in the original map data1(a step1). Therefore, cost of the on-vehicle apparatus7can be reduced because there is no need to prepare the original map data1and the simplified map data2individually.

Next described are examples of a method for generating the simplified map data2. First, from amongst the original map data1prepared on individual scales, the original map data1on a scale preferable to be displayed on the portable device4is selected.

Next, a part of the element data included in the original map data1on the scale selected (hereinafter referred to as “selected map data”) is eliminated. For example, traffic light data included in the road data and POT data included in the facility data are eliminated.

Next, a part of contents of the element data remaining and included in the selected map data is changed. For example, a font type of text data or/and a language type of the text data included in the selected map data is changed to a different type of the text data. Moreover, for example, a part of various facility icons included in the selected map data are changed to facility icons enjoyable for the fellow passenger. Furthermore, a part of the facility icons unimportant to the fellow passenger are eliminated. The simplified map data2generated in such a manner is registered in the simplified map database5.

Thus, the simplified map data2is generated by omitting a part of the element data included in the original map data1. Therefore, it is possible to prevent a large increase in cost of the on-vehicle apparatus7. Moreover, since the simplified map data2is generated based on the original map data1on one scale, a data volume of the simplified map database5can be significantly reduced as compared to a database including the original map data1on various scales.

Since the simplified map data2is generated by eliminating a part of the element data such as the POI data, when a map based on the simplified map data2is displayed, an amount of information provided to a user can be reduced. Therefore, an easy-to-understand map can be provided to the fellow passenger. Moreover, icons such as the facility icons and the language type and the font type of the text data are changed to be friendlier to the fellow passenger. Therefore, the on-vehicle apparatus7can provide a map more enjoyable for the fellow passenger.

For example, when the fellow passenger is a child, the on-vehicle apparatus7can display a map that shows a same area as a map at which the driver looks and that is indicated with illustrations or the like, for easy understanding even for children, on the portable device4such as a game console carried by the fellow passenger. As a result, the map is easier for the fellow passenger to understand and communication between the driver and the fellow passenger can be promoted. Moreover, in this case, a part of the map (e.g. icons) may be shown in animation.

Moreover, when the mother tongue (a first language) of the driver is different from the mother tongue (a second language) of the fellow passenger, a map having the text data in the second language changed from the first language can be displayed on the portable device4carried by the fellow passenger. As a result, since the map is easier for the fellow passenger to understand, communication between the driver and the fellow passenger can be promoted. For example, when the first language is Japanese and the second language is Chinese, Japanese text data is displayed on the map on the on-vehicle apparatus7at which the driver looks, and Chinese text data is displayed on the map on the portable device4at which the fellow passenger looks.

When the fellow passenger is an elderly person, a map having the text data of which font type has been changed to be easily recognizable (in a large font size, etc.) to the fellow passenger can be displayed on the portable device4carried by the fellow passenger. As a result, since the map is easier for the fellow passenger to understand, communication between the driver and the fellow passenger can be promoted.

The aforementioned are examples of the method for generating the simplified map data2. However, out of the element data included in the original map data1, element data to be omitted or to be changed may be different from the element data described in the aforementioned examples. As a result, various types of the simplified map data2can be generated.

For example, road data of a road of which width is narrow, 3-D data, etc. may be omitted. Background color data that determines color shade of the map image generated based on the simplified map data2, may be changed.

As shown inFIG. 1A, the simplified map data2generated is converted to the map image by an image generator6(a step3). The map image is, for example, raster data and compressed in a predetermined compression technology to reduce data volume of the map image. A widely-known technology, such as JPEG (Joint Photographic Experts Group) and PIC, is used for the compression.

In response to a demand from the portable device4, the image generator6retrieves the simplified map data2of a necessary area (an area around a location of the vehicle8or an area specified by the portable device4) from the simplified map database5, and generates the map image based on the simplified map data2retrieved. The map image is transmitted to the portable device4from the image generator6(a step4) and is displayed on the portable device4.

FIG. 1Billustrates an example of a map image displayed on the portable device4. AndFIG. 1Cillustrates an example of a map image used for route guidance displayed on the display3of the on-vehicle apparatus7. As shown in a comparison between these drawings, the map image (FIG. 1B) displayed on the portable device4is easier to understand and more enjoyable than the map image (FIG. 1C) used for the route guidance displayed on the display3.

The map image (FIG. 1B) displayed on the portable device4is displayed like an illustration as compared to the map image (FIG. 1C) used for the route guidance, by changing the icons and a font type. Therefore, the map image (FIG. 1B) displayed on the portable device4is easier to understand and enjoyable for the fellow passenger. Moreover, since less text data is included in the map image (FIG. 1B) displayed on the portable device4as compared to the map image (FIG. 1C) used for the route guidance, complexity of contents of the map can be reduced.

Next described is an embodiment of an on-vehicle apparatus of the invention in detail. Hereinbelow, the embodiment is described by taking as an example an on-vehicle apparatus having a function of generating simplified map data from original map data. However, the on-vehicle apparatus is not limited to the embodiment, and may store the simplified map data beforehand.

A configuration of the on-vehicle apparatus in the embodiment is explained referring toFIG. 2.FIG. 2illustrates the configuration of the on-vehicle apparatus in the embodiment. In the explanation, an on-vehicle apparatus10inFIG. 2is a car navigation apparatus. However, configuration elements required to explain characteristics of the on-vehicle apparatus10are mainly indicated and descriptions of general configuration elements are omitted.

As shown inFIG. 2, the on-vehicle apparatus10includes a near field communication part11, a GPS part12, an informing part13, a storage part14, and a controller15.

The near field communication part11transmits and receives data to/from a portable device20by near field communication using Bluetooth (registered trademark). Similarly the portable device20also has a function of near field communication by Bluetooth (registered trademark). The portable device20is a portable device, such as a cell phone, a PHS (Personal Handy-phone System), a PDA (Personal Digital Assistant) and a game console.

The portable device20includes an operation part21, a display22, a controller23, a storage part24, and a near field communication part25. In response to an operation to the operation part21by a user of the portable device20, the controller23retrieves and executes a program of an application26stored in the storage part24. Thus, the on-vehicle apparatus10is communicably connected to the portable device20.

For example, the controller23demands a desired map image from the on-vehicle apparatus10via the near field communication part25by retrieving and executing the program of the application26. The controller23obtains the map image transmitted from the on-vehicle apparatus10in response to the demand and displays the map image on the display22. As described later, the map image displayed on the display22is generated based on the simplified map data. Therefore, the map image is suitable to a fellow passenger.

This embodiment explains a case where Bluetooth (registered trademark) is used for communication between the on-vehicle apparatus10and the portable device20. However, another wireless communication standard such as Wi-Fi (registered trademark) and ZigBee (registered trademark) may be used for the communication. Moreover, wire communication may be used for the communication between the on-vehicle apparatus10and the portable device20.

The GPS part12of the on-vehicle apparatus10includes a GPS antenna and a GPS receiver. The GPS antenna receives a GPS signal from a satellite and transmits the GPS signal to the GPS receiver. The GPS receiver outputs to the controller15GPS information generated by demodulating the GPS signal received from the GPS antenna.

The informing part13informs the user of the information. The informing part13includes a display, such as a liquid crystal display, and a sound output part that outputs sound based on sound information via an on-vehicle speaker. The display of the informing part13displays an image output from the controller15. The display of the informing part13is operable to display an image, for example, in WVGA size (800×480).

The storage part14stores an original map database14a, a simplified map database14b, and a program14c. The original map database14aincludes an original map data used for route guidance. The original map data is map data for generating a map image designed to be looked at by a driver while driving.

FIG. 3illustrates a data structure of the original map database14a. As shown inFIG. 3, the original map database14aincludes original map data Sd on each scale of, for example, “1:1000,” “1:2000,” “1:5000,” “1:10000,” “1:25000,” “1:50000,” “1:100000,” “1:200000,” “1:400000,” and “1:1000000.” Moreover, the original map data Sd on each scale includes element data Ed such as, road data, facility data, background data, and image data.

The road data includes, for example, node data and link data. The node data is information of nodes (points of elements) that are connecting points of roads. The node data includes attribute information such as a longitude, a latitude and an altitude of each node, and a junction of roads, and a fork in a road, width of a road, and the type of a road (national road, prefectural road, highway, etc.). The link data is information of links that link the nodes. The link data includes attribute information such as inclination, and a raised or an underground part of each link (between nodes), and distance information.

The facility data includes types of facilities (e.g. school, convenience store, bank, park, etc.), location coordinates indicating locations of the facilities, area information indicating areas of the facilities, and POI data including detailed information on the facilities.

The background data includes background color data and data indicating terrain, etc. Moreover, the image data includes data of images such as facility icons and a crossroad icon.

Referring back toFIG. 2, the configuration of the on-vehicle apparatus10is described. The simplified map database14bincludes the simplified map data. The simplified map data is map data for generating the map image to be transmitted to the portable device20.

The on-vehicle apparatus10has a storing function of storing the simplified map data and the on-vehicle apparatus10may store the simplified map data in any manner. Therefore, a storage manner is not limited to the manner shown in this embodiment where the storage part14of the on-vehicle apparatus10has the simplified map database14bincluding the simplified map data. For example, the storage part14may include a storage apparatus dedicated to storing the simplified map database14b. Moreover, a part of a storage area of the storage part14may be a storage area for storing the simplified map data. Furthermore, the on-vehicle apparatus10may include a storage apparatus dedicated to storing the simplified map data separately from the storage part14.

A method for generating the simplified map data includes, but is not limited to a case, explained in this embodiment as an example, where the simplified map data is generated from the original map data by a processing part15c, described below, of the controller15. In other words, the simplified map data generated from the original map data does not necessarily need to be generated in an on-vehicle apparatus. For example, the on-vehicle apparatus may obtain the simplified map data generated beforehand, from a predetermined server (a server installed in, for example, an external center) on a network via a network communication part (not illustrated), and may store the simplified map data on the on-vehicle apparatus. Moreover, when the on-vehicle apparatus10is manufactured, the simplified map data may be stored on the on-vehicle apparatus10. Furthermore, the on-vehicle apparatus may retrieve the simplified map data from a portable recording medium storing the simplified map data via a reader (not illustrated), and may store the simplified map data retrieved on the on-vehicle apparatus.

The controller15controls the entire on-vehicle apparatus10. The controller15includes a location-information obtaining part15a, a route guidance part15b, the processing part15c, an image generator15d, a receiver15e, and a transmitter15f.

FIG. 2illustrates a functional configuration of the controller15. The controller15physically includes a computer having a CPU (Central Processing Unit), a ROM (Read Only Memory) and a RAM (Random Access Memory). The CPU retrieves the program14cstored on the storage part14(or the ROM) and executes the program14cusing the RAM as a working area. As a result, functions of the location-information obtaining part15a, the route guidance part15b, the processing part15c, the image generator15d, the receiver15e, the transmitter15f, etc. are implemented. The on-vehicle apparatus10can obtain the program14cby retrieving the program14cfrom a storage medium9, such as a non-transitory computer-readable memory card, storing the program14c, via a reader (not illustrated). The on-vehicle apparatus10can also obtain the program14cby downloading the program14cfrom a predetermined server on a network via a network communication part (not illustrated).

The location-information obtaining part15aobtains location information (concretely, latitude information and longitude information) indicating a location of the on-vehicle apparatus10at a point in time, based on the GPS information output from the GPS part12. The location information indicates the location of a vehicle on which the on-vehicle apparatus10is installed.

The route guidance part15bprovides the route guidance to show a route to a destination of the vehicle, to the driver. The route guidance part15bobtains a part of an area from the original map data on one of the scales included in the original map database14a. Concretely, the route guidance part15bobtains an area required for the route guidance, out of the original map data on a scale selected by the user of the on-vehicle apparatus10.

For example, when a scale of “1:5000” is selected by the user of the on-vehicle apparatus10, the route guidance part15bobtains only an area required for the route guidance, out of the original map data on the scale of “1:5000” from the original map database14a.

The route guidance part15bdetermines the area required for the route guidance, for example, based on a destination specified by the user of the on-vehicle apparatus10and the location information (a location of the vehicle) that the location-information obtaining part15aobtains.

Then the route guidance part15bgenerates the map image, for example, in WVGA size, based on the original map data only of the part of the area obtained from the original map database14a. Then the route guidance part15boutputs the map image generated to the informing part13and displays the map image on display of the informing part13. Moreover, the route guidance part15bsets a route to the destination if the destination is set. Then the route guidance part15bcauses the sound output part of the informing part13to output voice guidance guiding the vehicle to travel along the route set.

The processing part15cgenerates the simplified map data by omitting a part of the element data included in the original map data.FIG. 4illustrates an example of a procedure where the processing part15cgenerates the simplified map data. Referring toFIG. 4, the procedure for generating the simplified map data is concretely described.

FIG. 4illustrates only an example of the procedure for generating the simplified map data, and the procedure for generating the simplified map data includes, but is not limited to the procedure shown inFIG. 4. The procedure for generating the simplified map data may be any procedure where a part of the element data included in the original map data is omitted and the simplified map data is generated.

As shown inFIG. 4, the processing part15eselects one scale from amongst many scales. Then the processing part15cretrieves the original map data on the scale selected (in other words selected map data) from the original map database14a(a step S10). The processing part15cselects a scale on which a map is easy for the fellow passenger to understand.

In many cases, the fellow passenger desires to look at a map of a wide area, to an extent, rather than a detailed map. In other words, a scale of, for example, “1:10000” or “1:25000,” is preferable to the fellow passenger in many cases rather than a scale of, for example, “1:1000” or “1:2000.” Therefore, the processing part15cselects a scale of, for example, “1:10000” and retrieves the selected map data on the scale of “1:10000.”

Next, the processing part15celiminates a part of the element data of the selected map data (a step S11). For example, the processing part15celiminates traffic light data included in the road data, the POI data included in the facility data, etc. in the selected map data.

Moreover, the processing part15cchanges a part of contents of the element data remaining and included in the selected map data. Accordingly, a font type and a language type of text data, icons, etc. included in the selected map data are changed and then the simplified map data is generated (a step S12).

For example, the text data included in the selected map data is changed to text data in a different font type, to text data in a different language type, etc. An arrow A1inFIG. 5indicates an example where the font type of text data “RESTAURANT” is changed. Moreover, an arrow A2inFIG. 5indicates an example where the character type of the text data “RESTAURANT” is changed. Furthermore, an arrow A3inFIG. 5indicates an example where the language type of the text data “RESTAURANT” is changed.

Moreover, for example, image data of a current location icon indicating a current location of the vehicle, facility icons, etc. included in the selected map data are changed to image data of the icons in different forms.FIG. 6Aillustrates an example where the current location icon is changed to a different icon. Furthermore,FIG. 6Billustrates an example where an icon for hospitals that is one of facility icons, is changed to a different icon.

Then the processing part15cregisters the simplified map data generated in the simplified map database14b(a step S13). As a result, the simplified map data generated is stored on the storage part14. Data (font types, icons, etc. and hereinafter referred to as “change data”) that the processing part15cuses to change a content of the element data, may be stored on the processing part15cbeforehand.

Moreover, the on-vehicle apparatus10may obtain the change data transmitted from an external apparatus and store the change data on the processing part15c. For example, the on-vehicle apparatus10may obtain the change data from a predetermined server storing the change data, on a network such as the Internet, via a network communication part (not illustrated), and may store the change data obtained on the processing part15c.

Furthermore, the application26of the portable device20may transmit the change data to the on-vehicle apparatus10, and the processing part15cmay obtain the change data via the receiver15e. In such a manner, the simplified map data can be generated based on the application26of the portable device20. Therefore, the user of the portable device20can look at the map image based on desired simplified map data only by changing the application26.

It is preferable that the processing part15cgenerates the simplified map data and registers the simplified map data generated to the simplified map database14bbefore the processing part15ccommunicates with the portable device20, in order to provide the map image speedily to the portable device20.

Referring back toFIG. 2, the configuration of the on-vehicle apparatus10is described. The image generator15dobtains the simplified map data from the simplified map database14b, in response to a demand from the portable device20, and generates the map image based on the simplified map data. For example, the image generator15dretrieves the simplified map data corresponding to an area based on the demand from the portable device20, and generates the map image based on the simplified map data retrieved.

A size of the map image generated by the image generator15dis bigger than a display size displayable on the display22of the portable device20. Since the image generator15dgenerates the map image bigger than the display size to be displayed on the display22of the portable device20, a certain range of a map can be displayed by scrolling the map without communication between the portable device20and the on-vehicle apparatus10.

In addition, the portable device20demands the map image of an area specified by a latitude and a longitude or of an area where the vehicle is located. When the portable device20demands the map image of an area specified by a latitude and a longitude, information including the latitude and the longitude is transmitted from the portable device20. The image generator15dretrieves, from the simplified map database14b, the simplified map data of the area corresponding to the latitude and the longitude transmitted by the portable device20, and generates the map image based on the simplified map data retrieved.

On the other hand, when the portable device20demands the map image of an area where the vehicle is located, information including the demand is transmitted by the portable device20. In this case, the image generator15dretrieves, from the simplified map database14b, the simplified map data of the area corresponding to the location information (the location of the vehicle) obtained from the location-information obtaining part15a, and generates the map image based on the simplified map data retrieved.

The receiver15eobtains a signal transmitted from the portable device20via the near field communication part11. For example, the receiver15ereceives, from the portable device20, a map demand signal including information indicating the aforementioned area demand. The transmitter15ftransmits the map image and the like generated by the image generator15dto the portable device20via the near field communication part11.

The above description explains that the icons, the language type, the font type, etc. are changed at a time when the processing part15cgenerates the simplified map data from the original map data. On the other hand, the icons, the language type, the font type, etc. may be changed at a time when the image generator15dgenerates the map image from the simplified map data. In this case, the change data (font types, icons, etc.) used for a change of the contents of the element data is stored on the image generator15dbeforehand.

Also, in this case, the application26of the portable device20may transmit the change data to the on-vehicle apparatus10, and the image generator15dmay obtain the change data via the receiver15e. In such a manner, the user of the portable device20can look at his/her desired map image only by changing the application26.

Moreover, multiple icons, language types, font types, etc. may be prepared as selectable change data in the simplified map database14b. In this case, the image generator15dcan select icons, a language type, a font type, etc. in response to a demand from the portable device20, and can generate the map image having the icon selected in the language type and the font type selected.

For example, icons and a font type suitable to each age group such as elementary school, junior high school, and high school, may be prepared. In this case, an age group is specified with the portable device20. Based on the age groups specified, the image generator15dselects icons, a font type, etc. and provides a map image having the icons selected in the font type selected. Moreover, text data in various language types may be prepared, and from amongst the various language types, a language type specified by the portable device20is selected and the map image in the language type selected may be provided.

Furthermore, for example, icons and a font type for each category of, for example, sex of male or female, season, and region, may be prepared. In this case, too, icons and a font type in the category specified are selected, and the map image having the icons selected in the font type selected is provided.

In such a manner, the preparation of various types of icons and fonts allows the fellow passenger who operates the portable device20to be provided with a map suitable for him/her and to enjoy looking at the map. In addition, according to the age group, the sex, the season, the region, etc. mentioned above, the image generator15dmay change the background color or may change types of the element data (POI data, etc.) to be omitted.

Next described is concrete behavior of the on-vehicle apparatus10in this embodiment referring toFIG. 7.FIG. 7illustrates a flowchart showing main process procedure performed by the on-vehicle apparatus10.

As shown inFIG. 7, the on-vehicle apparatus10determines whether or not the receiver15ehas received, from the portable device20, a data-generation instruction signal for an instruction to generate the simplified map data (a step S20). When the receiver15ehas received the data-generation instruction signal (Yes in the step S20), the processing part15cgenerates the simplified map data based on the original map data in response to the data-generation instruction signal, and registers the simplified map data generated in the simplified map database14bin the storage part14(a step S21).

The data-generation instruction signal transmitted from the portable device20includes specification information specifying a language type, a font type, icons, etc. to which an original language type, an original font type, and original icons, etc are changed. Based on the specification information included in the data-generation instruction signal, the processing part15cgenerates the simplified map data by, for example, changing the language type, the font type, the icons, etc. of the text data.

A content of the specification information included in such a data-generation instruction signal can be changed by a user operation to the operation part21of the portable device20. For example, the fellow passenger who carries the portable device20can specify a content of an element changeable or selectable, such as the language type, the font type, the icons, etc., by operating the operation part21. One of the scales, the element data to be omitted, etc. may be specified by the user operation to the operation part21of the portable device20.

In the step S20, when the receiver15ehas not received the data-generation instruction signal (No in the step S20), it is determined whether or not the receiver15ehas received, from the portable device20, the map demand signal for a demand to transmit the map image (a step S22). The map demand signal is transmitted with a predetermined period from the portable device20to the on-vehicle apparatus10during execution of the application26.

When the receiver15ehas received the map demand signal (Yes in the step S22), the image generator15dobtains the simplified map data from the simplified map database14bin the storage part14. Then, based on the simplified map data, the image generator15dgenerates the map image of an area corresponding to a demand from the portable device20. And then the transmitter15ftransmits the map image generated by the image generator15dto the portable device20(a step S23).

In the step S22, when the receiver15ehas not received the map demand signal (No in the step S22), it is determined whether or not the receiver15ehas received, from the portable device20, a destination setting signal for an instruction to set a destination (a step S24). The destination setting signal includes destination information specifying a destination of the vehicle.

When the receiver15ehas received the destination setting signal (Yes in the step S24), the route guidance part15bsets the destination specified by the destination information included in the destination setting signal, as a route guidance destination. Then the route guidance part15bprovides the route guidance leading to the destination (a step S25).

While looking at the map image displayed on the display22, the fellow passenger that is the user of the portable device20can specify a location of the destination of the vehicle by operating the operation part21. As a result, the destination setting signal including the destination information is transmitted to the on-vehicle apparatus10from the controller23of the portable device20. In such a manner, it is possible to specify the destination of the route guidance provided by the on-vehicle apparatus10, by using the portable device20.

When process of the step S21, S23, or S25ends or when the receiver15ehas not received the destination setting signal in the step S24(No in the step S24), the process goes back to the step S20.

As described above, the on-vehicle apparatus10in this embodiment includes the storage part14that stores the simplified map data generated by omitting a part of the element data included in the original map data used for the route guidance. The image generator15dgenerates the map image based on the simplified map data stored on the storage part14, and then the transmitter15ftransmits the map image to the portable device20.

Therefore, the map image based on the simplified map data of which contents are simplified as compared to the original map data used for the route guidance is transmitted to the portable device20. As a result, the fellow passenger using the portable device20can look at a map more preferable to the fellow passenger. In addition, the on-vehicle apparatus10does not have to prepare the simplified map data2separately from the original map data1but generates the simplified map data by omitting a part of the element data included in the original map data. Therefore, a large cost increase of the on-vehicle apparatus10can be prevented.

Moreover, information amount included in the map image based on the simplified map data is reduced. Therefore; it is possible to provide map information easy for the fellow passenger to understand. Furthermore, it is possible to provide a map enjoyable for the fellow passenger due to the change of icons such as the facility icons, and types of the language and the font of the text data.

The embodiments of the invention have been described in detail based on the drawings. However, the embodiments are examples and it is possible to implement the invention in other forms other than the aforementioned embodiments, by changing, converting, and improving the aforementioned embodiments based on knowledge of the skilled in the art.

For example, a processing part15cmay generate simplified map data, if necessary, instead of having a simplified map database14b. In this manner, an original map database14aand the processing part15cwork together to bear functions of the simplified map database14b. As a result, a storage capacity needed for the simplified map database14bin the storage part14can be reduced.

In the aforementioned embodiments, the simplified map data prepared beforehand is registered in the simplified map database14bin the storage part14, and when the map demand signal is received from the portable device20, the image generator6retrieves the simplified map data of a necessary area from the simplified map database14b, and the transmitter15ftransmits to the portable device20the map image based on the simplified map data. On the other hand, simplified map data is not prepared beforehand, but when a map demand signal is received from a portable device20, a processing part15cmay retrieve the original map data of a necessary area from the original map database14a, may generate the simplified map data based on the original map data and then may cause the simplified map data to be stored in a RAM in a controller15. In this case, an image generator6retrieves the simplified map data from the RAM and a transmitter15ftransmits a map image based on the simplified map data, to the portable device20.

In the aforementioned embodiments, the image generator15dgenerates the map image compressed in a method such as JPEG and PIC, and the map image is transmitted to the portable device20. On the other hand, an image generator15dmay clip a part of simplified map data as a map image, corresponding to a necessary area, and may transmit the map image (simplified map data) to a portable device20. In this case, a controller23of the portable device20generates an image to be displayed on a display22, based on the simplified map data obtained from an on-vehicle apparatus10.

Moreover, in the aforementioned embodiments, the simplified map data is generated by eliminating a part of the element data included in the original map data (e.g. the traffic light data included in the road data, and the POI data included in the facility data), and then by changing a part of the contents (font type, language type, icons, etc.) of the element data remaining and included in the original map data of which a part of the element data is eliminated. On the other hand, original map data of which a part of element data is only eliminated may be used as simplified map data. In this case, an on-vehicle apparatus transmits a map image based on the simplified map data, to a portable device. Then the portable device changes the font type, the language type, the icons, etc. using change data stored on the portable device. As a result, it is easier to reflect the taste of a user to the map image to be displayed on the portable device. Therefore, it is possible to provide map information easier to understand and more enjoyable for the user.

As described above, the on-vehicle apparatus of the invention is effective in transmission of a map image easy to understand and enjoyable mainly for a fellow passenger, to a portable device. This invention is suitable to car apparatuses, especially, car navigation apparatuses.

While the invention has been shown and described in detail, the foregoing description is in all aspects illustrative and not restrictive. It is therefore understood that numerous other modifications and variations can be devised without departing from the scope of the invention.