JP2001033257A - Car navigation device and switching method of brightness and chroma of its display screen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a car navigation device requiring no difficult wiring in installing it without increasing the cost of itself, capable of automatically switching the brightness of a screen in response to the ambient situation, and having high operability. SOLUTION: This car navigation device is provided with a tunnel travel detecting means 23 detecting whether the road on which this vehicle is located is a tunnel or not based on map information, a day/night judging means calculating the sunrise time and sunset time based on the present time information of a GPS satellite and the latitude and longitude of the vehicle position and judging whether it is daytime or night, and a display screen brightness/chroma switching means 24 automatically switching the brightness and chroma of a display screen 3a based on the instructions from the tunnel travel detecting means 23 and day/night judging means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a car navigation device having a saturation switching unit and a method for switching brightness and saturation of a display screen thereof.

[0002]

2. Description of the Related Art In recent years, a plurality of GPs have been
GPS (Glob) is a positioning system that receives navigation radio waves transmitted from the S satellite to the ground and detects the current position.
A car navigation device capable of displaying the position of a vehicle using an al positioning system (global positioning system) has been widely used.

[0003] In such a car navigation device, by switching the brightness (brightness / saturation) that is easy to see during operation depending on the brightness around the display screen, the screen is brightened during bright daytime so that it is not difficult to see. In dark nights, it is required to darken the screen so that it is not dazzling.

[0004] As a conventional car navigation apparatus and a method for switching the brightness and saturation of a display screen thereof, a car navigation apparatus is connected to a wiring of a small lamp or a headlight of an automobile.
The method of dimming the screen when the light is turned on, the sunrise based on the current time information of GPS satellites and the latitude and longitude of the vehicle position,
Calculates the sunset time and automatically darkens when it is determined to be dark. Monitors the number of supplementary GPS satellites. If the number of supplementary satellites decreases or cannot be complemented at all, determine that it is a tunnel or shade of trees. A method of automatically darkening the screen, a method of equipping the car navigation device itself with a brightness sensor and automatically darkening the screen when it is determined that the surroundings are dark have been proposed.

[0005]

However, the above-described conventional car navigation apparatus and the method for switching the brightness and saturation of the display screen thereof have the following problems.

That is, in the method of connecting to the wiring of a small lamp or a headlight and dimming the screen when the light is turned on, it is necessary to perform wiring work that is difficult for a layman to install a car navigation device in a car. Therefore, the car navigation device cannot be easily installed in the car.

In the method of calculating the sunrise and sunset times based on the current time information of the GPS satellites and the latitude and longitude of the position of the vehicle, and judging that the time is dark, the screen is automatically darkened. It is impossible to darken the screen.

Further, a method of monitoring the number of supplementary GPS satellites and automatically darkening the screen by judging a tunnel or a shade of a tree when the number of supplementary satellites decreases or cannot be complemented at all,
There is a problem that the screen is automatically darkened even in the daytime even when the surroundings are bright even during daytime depending on the location where the GPS antenna is installed on the vehicle while traveling on the underpass of the building or the GPS antenna.

Further, in a method in which a brightness sensor is provided in the car navigation device itself and the screen is automatically darkened when it is determined that the surroundings are dark, the price of the car navigation device itself increases, and the car navigation device itself is inexpensive at a low price. It is difficult to provide a navigation device.

The present invention solves the above-mentioned conventional problems, and does not increase the price of the car navigation device itself, does not require difficult wiring when installing the car navigation device, and reduces the brightness of the screen. It is an object of the present invention to provide a highly operable car navigation device that can automatically switch between in accordance with a surrounding situation.

[0011]

To achieve the above object, the present invention provides a tunnel detecting means for detecting whether or not a road on which a vehicle position is located is a tunnel based on map information;
It has day and night determining means for calculating the sunrise and sunset times based on the current time information of the GPS satellites and the latitude and longitude of the position of the vehicle and determining whether it is daytime or nighttime, and is displayed according to instructions from the tunnel running detecting means and day / night determining means. A car navigation apparatus having a display screen brightness / saturation switching means for automatically switching brightness and saturation of a screen is provided.

According to the present invention, the display screen is automatically darkened by the tunnel traveling detecting means in the tunnel driving in the daytime, and the display screen is automatically darkened by the day / night determining means in the nighttime. A high car navigation device can be provided.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention provides a display screen for displaying information, a map information storage unit for storing map information, and a position of the own vehicle by measuring the position of the own vehicle. Self-vehicle position detecting means for detecting, a tunnel detecting means for detecting whether or not the road on which the self-vehicle position is located is a tunnel based on map information; current time information of GPS satellites and latitude and
Day / night judgment means that calculates sunrise and sunset times based on longitude to judge daytime or nighttime, and display screen brightness / color saturation that automatically switches the brightness or saturation of the display screen according to instructions from tunnel running detection means and day / night judgment means. A car navigation device equipped with a saturation switching means. The display screen is automatically darkened in a tunnel running in the daytime, and the display screen is automatically darkened in the nighttime, so that operability can be improved. It has the action of:

According to a second aspect of the present invention, there is provided a display screen for displaying information, a map information storage unit for storing map information, and an own vehicle for measuring the position of the own vehicle and detecting the own vehicle position. Position detecting means, tunnel running detecting means for detecting whether the road on which the vehicle position is located is a tunnel based on map information, and connecting to wiring of a small lamp or a headlight to detect whether or not the light is turned on. A car navigation device comprising: a light-on detecting means for turning on; and a display screen-lightness / saturation switching means for automatically switching brightness or saturation of a display screen according to an instruction from the tunnel traveling detecting means and the light-on detecting means. At night or when traveling in a tunnel where it is necessary to turn on the light, the display screen is automatically darkened by the light lighting detection means, and there is no need to turn on the light during daytime driving. In tunnel running Forgotten lighting of travel and light tunnel has the effect of automatically dims the display screen by a tunnel running detecting means, it can have high operability.

According to a third aspect of the present invention, there is provided a display screen for displaying information, a map information storage unit for storing map information, and an own vehicle for measuring the position of the own vehicle and detecting the own vehicle position. Position detecting means, tunnel detecting means for detecting whether or not the road on which the vehicle position is located is a tunnel based on the map information;
Day and night determining means for calculating the sunrise and sunset times based on the current time information of the PS satellite and the latitude and longitude of the position of the vehicle to determine whether it is daytime or nighttime; Equipped with display brightness / saturation switching means for automatically switching between brightness and saturation, based on road information from the map information storage unit, determines whether or not the vehicle is on the tunnel, and determines that it is on the tunnel If it is, the screen of the display device is darkened, and if it is determined that the position of the own vehicle is not on the tunnel, the sunrise and sunset times are calculated based on the information on the position of the own vehicle, and the current time is calculated from the information of the current time. Judgment of daytime or nighttime, the screen is brightened if it is determined that it is daytime, and the screen is darkened if it is determined that it is nighttime.The method of switching the brightness and saturation of the display screen of the car navigation device Ah Has the effect that the daytime tunnel running automatically dim the display screen, automatically dim the display screen if at night, can have high operability.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram showing a configuration of a car navigation apparatus according to Embodiment 1 of the present invention.

As shown in FIG. 1, the car navigation apparatus according to the first embodiment has a CPU (Central Processing Unit) 1 for controlling the operation of the car navigation apparatus, and a user having a CP.
An input device 2 for inputting an operation command or the like to U1;
A display device 3 for displaying and outputting the processing result of U1, a graphic controller 4a for performing a screen display process of the display device 3 based on input image information and the like, and image data to be displayed on the display device 3 input from the graphic controller 4a A display control device 4 having a video RAM 4b for temporarily storing the information, a GPS receiver 5 for locating and outputting the position of the own vehicle by GPS, and detecting a speed and a right and left inclination of the own vehicle to transmit navigation radio waves from GPS artificial satellites. A self-contained navigation unit 5a capable of positioning the position of the vehicle even in a tunnel where reception is not possible, and an interface for synthesizing an input from the GPS receiver 5 and an input from the self-contained navigation unit 5a and converting the data into data that can be input to and output from the CPU 1. 5b, an antenna 6 for receiving a navigation radio wave from a GPS artificial satellite, and map information and the like are recorded. D-ROM (read-only compact disk memory) and 7, CD-ROM drive 8 for outputting read information recorded on the CD-ROM 7
A ROM 9 storing a program for controlling the CPU 1 and graphic data to be displayed on the display device 3;
A RAM 10 for storing data temporarily generated when the PU 1 operates, a voice output control device 11 for performing a voice output control based on a command from the CPU 1, and a voice output by a voice signal input from the voice output control device 11. Speaker 12 to be output, CPU 1, input device 2, display control device 4, interface 5b, CD-ROM drive 8,
It is provided with a bus line 13 commonly connected to the ROM 9, the RAM 10, and the audio output control device 11.

FIG. 2 is a block diagram showing a functional configuration of the brightness switching operation of the car navigation device according to the first embodiment.

As a functional configuration of the brightness switching operation in the car navigation device, as shown in FIG.
Display device 3, GPS receiver 5, self-contained navigation unit 5
a (these are the same as those in FIG. 1 and are denoted by the same reference numerals and description thereof is omitted), a display screen 3a of the display device 3 that displays information such as a map and the position of the vehicle, and a GPS reception Self-vehicle position detecting means 21 for measuring the coordinates (latitude / longitude) of the self-vehicle position based on the position information signal output from the aircraft 5 and the self-contained navigation unit 5a and detecting the self-vehicle position;
And a map information storage unit 22 configured to store map information constituted by the CD-ROM drive 8 and the vehicle position information and map information storage unit 22 output from the vehicle position detection unit 21.
And a position output from the GPS receiver 5 and a tunnel running detecting means 23 for determining whether or not the running road is a tunnel based on the map information stored in the tunnel running detecting means 23 Display screen brightness / saturation switching means 24 for determining whether to increase or decrease the brightness of the display screen 3a based on the information signal and the current time information
It has.

The vehicle position detecting means 21, the tunnel running detecting means 23 and the display screen brightness / saturation switching means 24 are R
The program is stored in the OM 9, and the operation is executed by the CPU 1 performing processing according to the program. In the first embodiment, the general-purpose CPU 1
Is used to execute the operation by program processing, but may be configured by a dedicated logic circuit.

In the car navigation system according to the first embodiment having the above-described components, a method for switching between display brightness and saturation will be described below.

FIG. 3 is a flowchart showing the entire operation of the car navigation device according to the first embodiment of the present invention.

When the car navigation system provides the current location guidance, the own vehicle position detecting means 21 determines the transmission time of radio waves from a plurality of GPS satellites included in the navigation radio waves received by the GPS receiver 5, the orbit around the earth, and the like. The distance to each GPS satellite is calculated from the arrival time of the received radio wave to detect the position of the vehicle. In addition, GPs under tunnels and elevated roads
When the navigation radio wave from the S satellite does not reach, the position of the own vehicle is detected from the speed of the own vehicle and the inclination of the left and right, which are the outputs from the independent navigation unit 5a (S1).

Next, the CPU 1 determines whether or not the position of the own vehicle is on a tunnel based on the road information from the map information storage unit 22 (S2). If it is determined that it is on the tunnel, a process for darkening the screen described later is performed (S5).

If it is determined that the position of the own vehicle is not on the tunnel, the CPU 1 calculates the sunrise and sunset times based on the information of the position of the own vehicle output from the own vehicle position detecting means 21 and calculates the position of the own vehicle. It is determined whether the present time is daytime or nighttime based on the current time information output from the detecting means 21 (S3). When it is determined that the present time is daytime, a process of brightening the screen described later is performed (S4). If it is determined that the current time is night, a process for darkening the screen described later is performed (S5).

The process of brightening the screen (S4) includes a method of increasing the brightness of the display screen 3a itself, a method of increasing the saturation of the map and information displayed on the display screen 3a, and a method of increasing the saturation of the display screen 3a.
By changing the color of the map or information displayed in a to a color for daytime, the screen is changed to a bright screen that is easy to see in daytime.

The process of darkening the drawing (S5) includes a method of lowering the brightness of the display screen 3a itself, a method of lowering the saturation of a map or information displayed on the display screen 3a, and a method of reducing the saturation of the display screen 3a.
Is changed to a dark screen that is easy to see at night, for example, by changing the color of the map or information displayed on the screen to the color for night.

(Embodiment 2) The car navigation apparatus according to Embodiment 2 automatically switches the display screen brightness / saturation according to the lighting of a light in a daytime tunnel driving or the like.

This car navigation device, similar to the first embodiment, has a display screen (not shown) for displaying information, a map information storage unit for storing map information, and a vehicle for measuring the position of the vehicle. Own vehicle position detecting means for detecting a position,
Tunnel running detection means is provided for detecting whether or not the road on which the vehicle position is located is a tunnel based on the map information. As a characteristic configuration, there is provided a light-on detecting means connected to the wiring of the small lamp or the headlight to detect whether or not the light is on. And
The display screen brightness / saturation switching means performs an operation of automatically switching the brightness or saturation of the display screen in response to an instruction from the tunnel running detection means and the light lighting detection means.

In the car navigation system according to the second embodiment, the display screen is automatically darkened by the light-on detecting means at night or when traveling in a tunnel when it is necessary to turn on the light, and it is necessary to turn on the light during daytime traveling. In traveling in a short tunnel where there is no traffic, or in a tunnel traveling when the user forgets to turn on the light, the display screen is automatically darkened by the tunnel traveling detecting means, and the operability can be improved.

[0032]

As described above, according to the car navigation system of the present invention, the following effects can be obtained.

The user does not need to perform complicated wiring when installing the car navigation device, and can easily install the car navigation device. Further, the screen is automatically darkened during use in a daytime tunnel driving. The display screen is easy to see,
Further, since the display screen is not dazzling, it is possible to drive safely, and it is possible to provide a car navigation device excellent in installation, operability, and safety.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a car navigation device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a functional configuration of a brightness switching operation of the car navigation device.

FIG. 3 is a flowchart showing the entire operation of the car navigation device.

[Explanation of symbols]

Reference Signs List 1 CPU (central processing unit) 2 input device 3 display device 3a display screen 4 display control device 4a graphic controller 4b video RAM 5 GPS receiver 5a self-contained navigation unit 5b interface 6 antenna 7 CD-ROM (read-only compact disk memory) 8 CD-ROM drive 9 ROM 10 RAM 11 Voice output control device 12 Speaker 13 Bus line 21 Own vehicle position detecting means 22 Map information storage unit 23 Tunnel running detecting means 24 Display screen brightness / saturation switching means

Claims (3)

[Claims] A display screen for displaying information; a map information storage unit for storing map information; a vehicle position detecting means for measuring a position of the vehicle to detect a vehicle position; Tunnel detecting means for detecting whether or not the road on which the car position exists is a tunnel, day and night for judging day or night by calculating the sunrise and sunset times based on the current time information of the GPS satellites and the latitude and longitude of the vehicle position. A car navigation device comprising: a determination unit; and a display screen brightness / saturation switching unit that automatically switches brightness and saturation of a display screen according to instructions from a tunnel traveling detection unit and a day / night determination unit. A display screen for displaying information; a map information storage unit for storing map information; a vehicle position detecting means for measuring a position of the vehicle to detect a vehicle position; Tunnel running detecting means for detecting whether or not the road on which the car position is located is a tunnel; light lighting detecting means for detecting whether a light is turned on by connecting to a wiring of a small lamp or a headlight; and tunnel running detecting. And a display screen brightness / saturation switching means for automatically switching the brightness and saturation of the display screen in response to an instruction from the means and the light lighting detection means. 3. A display screen for displaying information, a map information storage unit for storing map information, a vehicle position detecting means for measuring the position of the vehicle and detecting the position of the vehicle, Tunnel detecting means for detecting whether or not the road on which the car position exists is a tunnel, day and night for judging day or night by calculating the sunrise and sunset times based on the current time information of the GPS satellites and the latitude and longitude of the vehicle position. Judgment means, and display screen brightness / saturation switching means for automatically switching the brightness and saturation of the display screen in accordance with instructions from the tunnel running detection means and day / night judgment means, and based on the road information from the map information storage unit. It is determined whether or not the position of the vehicle is on the tunnel.If it is determined that the vehicle is on the tunnel, the screen of the display device is darkened. Sunrise, based on Calculate the time of sunset, determine whether the current time is daytime or nighttime from the information of the current time, make the screen brighter if it is determined to be daytime, and darken it if it is determined to be nighttime A method for switching brightness and saturation of a display screen of a car navigation device.