JPH0854249A - Navigation system - Google Patents

Abstract

PURPOSE:To obtain a navigation system in which a user can set a route to a destination while reducing power consumption. CONSTITUTION:A main road decision means 25 makes a decision whether a navigation system is required to be used based on a route to a destination inputted from an input means 21, map information of a memory means 22, and a current position calculated by a current position calculation means 24. When navigation system is not required to be used, a back-light control means 26 puts out the back-light of a display means 27, i.e., an LCD.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a function of determining a current position based on information from a stand-alone sensor such as GPS or a self-standing sensor such as a geomagnetic sensor, and an optical disk or IC card storing map information. The present invention relates to a navigation system having a function of searching / displaying information from a memory.

[0002]

2. Description of the Related Art In recent years, for vehicle use, a combination of a stand-alone sensor such as GPS, a geomagnetic sensor, or current position information obtained by combining them and map information stored in an optical disk, an IC card, or the like, Liquid crystal display (Liquid
There is an increasing demand for navigation systems that perform navigation by displaying them on display means such as a Crystal Display (hereinafter referred to as LCD), and various navigation systems have been developed.

[0003]

However, in the above-mentioned conventional configuration, the backlight of the LCD, which is the display means, is always on while the navigation is in use unless the user turns off the power. In particular, in navigation for vehicles and mobiles, there is a problem of power saving because the power supply battery has a limit.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a navigation system in which a user can set a route to a destination and reduce power consumption.

[0005]

In order to achieve this object, a navigation system of the present invention is a navigation system which allows a user to set a route to a destination, and the user can reach the destination. An input means for inputting the route, a current position calculating means for detecting the current position, a map information reading means for reading map data from a memory storing map information, a current position calculating means and a map information reading means. Display means for displaying the data obtained from, the discrimination means for discriminating the necessity of navigation based on the data obtained from the current position calculation means and the map information reading means, and based on the result of this discrimination means And a control means for automatically changing the display level of the display means.

The discriminating means determines whether or not the road currently being traveled is a main road, and also determines the continuity of traveling on the road which is currently traveling based on the data from the input means to the destination. Based on the determination result, it is determined whether navigation is necessary.

A liquid crystal display is used as the display means, and the voltage applied to the liquid crystal is lowered while the determination means determines that navigation is unnecessary.

Further, a liquid crystal display is used as the display means, and while the judging means judges that the navigation is not necessary, the voltage to the backlight for irradiating the liquid crystal is lowered to reduce the irradiation amount to the liquid crystal. cut back.

A liquid crystal display is used as the display means, and the backlight for illuminating the liquid crystal is turned off while the determining means determines that navigation is not required.

Further, a CRT display is used as the display means, and the brightness of the display screen is lowered while the determination means determines that navigation is unnecessary.

A CRT display is used as the display means, and the display screen is turned off while the determination means determines that navigation is unnecessary.

[0012]

With this structure, the voltage applied to the liquid crystal of the LCD as the display means can be automatically lowered while the navigation is not particularly required.

Further, when the navigation is not particularly required, it is possible to automatically lower the application of the voltage to the backlight of the LCD which is the display means.

Further, the backlight of the LCD as the display means can be automatically turned off while the navigation is not particularly required.

While the navigation is not particularly required, the brightness of the display screen of the CRT display, which is the display means, can be automatically lowered.

Further, the display screen of the CRT display which is the display means can be automatically turned off while the navigation is not particularly required.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of the navigation system in one embodiment of the present invention, and FIG. 2 is a block diagram of the navigation system in one embodiment of the present invention.

As shown in FIGS. 1 and 2, the storage means 22
In order to digitize map information and store it as map data 17, C has a large storage capacity in recent years.
D-ROM is mainly used. Map data 1
7 is selected by the input unit 21 which is the input unit 11, and the map data 17 digitized by the information reading unit 23 is read out and read into the RAM unit 13. The central processing unit (CPU) 14 allows the RAM unit 1
Map data 17 read in 3 is processed and video R
By being written in the AM (VRAM) unit 16, the map is displayed on the display unit 15, which is the display unit 27.

As the display unit 15, a CRT display, an LCD or the like is used, but in this embodiment, an LCD requiring a backlight is used. As a light source of this backlight, a cold cathode fluorescent tube or a hot cathode fluorescent tube is used, and a light guide method using a light guide plate such as acrylic is used as a method of using it, or light from the fluorescent tube is directly emitted from the back side of the LCD. The reflection method and the like can be mentioned, but the type of the light source and the irradiation method are not limited in this embodiment.

The current position calculating means 24 determines the current position based on the information obtained by the stand-alone type sensor such as GPS or the geomagnetic sensor. The navigation in this case may be of any type in this embodiment. When the current position is calculated, the main road determination means 25 determines whether or not the current navigation is required based on the current position information and the map data 17.

Various situations can be considered to determine whether navigation is required. For example, when navigation is required, the vehicle is traveling on a road that does not belong to a national highway, or the course of the vehicle is changed. Further, when navigation is not required, the vehicle is traveling on a highway, which is a main road, or a toll road, or is traveling on a national road or the like which the user has set a route for a while.

When the main road discriminating means 25 determines that navigation is unnecessary, the backlight control means 2
6, the backlight of the LCD is automatically turned off. Here, the LCD backlight is turned off and the LC
Image display data to D (current position information and map data 17
Etc.) may be interrupted. However, the positioning of the current position by the stand-alone sensor or the self-standing sensor must be performed at any time.

FIG. 3 is a flow chart of the navigation system in one embodiment of the present invention. Input means 21
When the user inputs the route from the vehicle to the destination, as shown in FIG. 3, in step 31, the information obtained from the stand-alone sensor such as GPS or the self-standing sensor such as the geomagnetic sensor Know your current location. Step 3
In step 2, it is determined whether the road currently running is a main road (for example, a highway or a toll road). Step 32
If it is determined that the vehicle is traveling on a main road in step 33, it is determined in step 33 whether or not the future navigation is required for traveling on the main road.

If it is determined in step 33 that navigation is unnecessary, the backlight of the LCD is turned off in step 34. Even after the backlight of the LCD is turned off, the current position of the vehicle is constantly measured in order to determine the current position of the vehicle.
In the case of S, the backlight of the LCD is turned on in step 37 when the radio waves from the artificial satellites are blocked, such as when entering the tunnel or traveling near an obstacle such as a building. . However, in that case, since it is not possible to measure the current position, the map of the last measured position is LC
D is displayed, or a caution statement or the like that cannot be positioned is displayed on the LCD by characters or the like.

When it is determined in step 35 that the positioning can be performed as usual, it is determined in step 36 whether navigation is required again, and when it is about to get off the highway or toll road soon. If it is confirmed that a right turn or a left turn is coming soon, go to Step 3
At 7, the LCD backlight is turned on again.

It has been described above that the backlight of the LCD as the display means 27 is turned off when the main road discriminating means 25 judges that navigation is not necessary. When the determination unit 25 determines that navigation is not necessary, the voltage applied to the liquid crystal of the LCD, which is the display unit 27, is reduced to save power consumption. Or LCD
It is conceivable to reduce the power consumption by reducing the voltage applied to the backlight and reducing the irradiation amount on the liquid crystal.

When a CRT display is used as the display means 27, the power consumption can be reduced by lowering the brightness of the display screen when the main road discriminating means 25 determines that navigation is unnecessary. . Further, when the main road discriminating means 25 discriminates that navigation is not necessary, the display screen of the CRT display may be turned off. However, in the CRT display, it takes a little time to display the display screen once after turning it off. Therefore, in the present embodiment, it is more suitable to lower the brightness of the former display screen.

As described above, in this embodiment, the user sets the route to the destination from the input means 21, and the current position and
It is the display means 27 when the main road discriminating means 25 judges the continuity of traveling such as when traveling on a main road such as an expressway or a toll road for a while, and the main road discriminating means 25 judges that navigation is unnecessary. By turning off the backlight of the LCD by the backlight control means 26, power consumption can be reduced.

[0030]

As described above, according to the present invention, in the navigation system in which the user can set the route to the destination, the display level of the display means is automatically set in the section not requiring the navigation. By lowering it, power consumption can be reduced. As a result, it is possible to realize an excellent navigation system that can reduce the load on the power supply battery and suppress the heat generation of the device.

[Brief description of drawings]

FIG. 1 is a device configuration diagram of a navigation system according to an embodiment of the present invention.

FIG. 2 is a block diagram of a navigation system according to an embodiment of the present invention.

FIG. 3 is a flowchart of a navigation system according to an embodiment of the present invention.

[Explanation of symbols]

 21 Input Means 22 Storage Means 23 Information Reading Means 24 Current Position Calculating Means 25 Main Road Discriminating Means 27 Display Means

Claims (7)

[Claims] 1. A navigation system that enables a user to set a route to a destination, wherein the user inputs an route to the destination and a current position calculation unit for detecting a current position. A map information reading means for reading map data from a memory storing map information; a display means for displaying data obtained from the current position calculating means and the map information reading means; and a current position calculating means. Discriminating means for discriminating the necessity of navigation based on data obtained from the map information reading means and control means for automatically changing the display level of the displaying means based on the result of the discriminating means. A navigation system comprising: 2. The determining means determines whether or not the road currently being driven is a main road, and also determines the traveling continuity of the road currently being driven from the data to the destination input from the input means. The navigation system according to claim 1, wherein whether or not navigation is required is determined based on the two determination results. 3. A liquid crystal display is used as the display means, and the voltage applied to the liquid crystal is lowered while the determination means determines that navigation is unnecessary. The navigation system according to item 2. 4. A liquid crystal display is used as the display means, and while the determination means determines that navigation is not necessary, the voltage to the backlight for illuminating the liquid crystal is lowered to irradiate the liquid crystal. The navigation system according to claim 1 or 2, wherein the amount is reduced. 5. A liquid crystal display is used as the display means, and the backlight for illuminating the liquid crystal is turned off while the determination means determines that navigation is unnecessary. Alternatively, the navigation system according to claim 2. 6. A CRT display is used as the display means, and the brightness of the display screen is lowered while the determination means determines that navigation is unnecessary. 2. The navigation system described in 2. 7. A CRT display is used as the display means, and the display screen is turned off while the determination means determines that navigation is not required. 2. The navigation system described in 2.