JPH0455886A - Information display device - Google Patents

Abstract

PURPOSE:To obtain the display screen which does not generate the flickering by after-images by varying and setting the scanning time of one screen of display information according to a shift speed, thereby allowing the shift time and the scanning time for one screen to coincide with each other. CONSTITUTION:A display device 4 arranged with many pieces of luminous bodies in the form of a matrix as well as a driving circuit section and a control circuit section are provided. The control circuit section varies and sets the scanning time of one screen above the display according to the luminous bodies of the display device 4 and the transfer of the lighting positions. The control circuit section varies and sets the scanning time of one screen of the display information according to the shift speed in such a manner and, therefore, the shift time and the scanning time for one screen are made to coincide with each other and the driving of the LEDs entailing the transfer of the lighting positions at all times is executed. The easily visible display screen which does not generate the flickering by the after-images is formed in this way.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an information display device for displaying, for example, text information for advertisements and guidance (hereinafter referred to as "display information"). In particular, this invention relates to a light emitting diode (
The present invention relates to an information display device that displays the display information while shifting it using a display device in which a large number of light emitting bodies such as r LED J (hereinafter referred to as r LED J ) are arranged in a matrix.

<Prior Art> Conventional information display devices of this type scan the entire display screen of a display device, drive each light emitting element to be lit based on display information read out from a memory, and designate its lighting position. The shift speed is changed sequentially.

FIG. 11 shows the timing for scanning the display screen of a display device whose display screen is formed by arranging a large number of LEDs in 16 rows by 16 columns.

In the figure, S O"" S I 5 is a row selection signal S for selecting each row of the display screen, and t is a row selection signal S for selecting each row of the display screen, and t is a line selection signal S for selecting each row of the display screen.
1t indicates the start time of scanning the screen, and 1t indicates the end time of the scanning. T1 is the time for scanning one screen (hereinafter referred to as "scanning time"), and this scanning time T1 is determined to be a constant value.

T2 is the time required to shift the lighting position to the LED in the adjacent column (hereinafter referred to as "shift time"), and this shift time is proportional to the shift speed.

During the period when the row selection signal S is on, each LED of the corresponding row is driven. In this case, the shift time T
During the first scan (indicated by diagonal lines in the figure) in Step 2, each LED is driven after the lighting position has been shifted, but during the second scan before the shift time T2 has elapsed, the lighting position is not shifted. Each LED is driven.

When the shift time T2 has elapsed, scanning is returned to the first row regardless of which row is being scanned, and the LEDs are subsequently driven sequentially with the shift of the lighting position.

<Problems to be Solved by the Invention> In the operation of the above information display device, the shift time T
2, if driving of an LED with a shift in lighting position and driving of an LED without a shift in lighting position coexist, flickering due to an afterimage occurs and the display screen becomes unsightly.

The present invention has been made in view of the above problem, and an object of the present invention is to provide an information display device that does not cause flickering due to afterimages and can provide an easy-to-read display screen.

<Means for Solving the Problems> The information display device of the present invention includes a display, a memory, a drive circuit section, and a control circuit section. The display device has a display screen formed by arranging a large number of light emitters in a matrix. The memory stores display information to be displayed on the display screen and a shift speed for shifting the display information on the display screen. The drive circuit unit scans the entire display screen of the display device, drives each light emitting body to be lit based on the display information input from the memory, and sequentially shifts the lighting position of the light emitter. The control circuit section variably sets the scanning time for one screen of display information in accordance with the shift speed input from the memory, and controls the drive of the light emitting body and the shift of the lighting position by the drive circuit section.

<Function> Since the control circuit section variably sets the scanning time for one screen of display information according to the shift speed, by matching the shift time Tz and the scanning time T1 for one screen, the lighting position can always be shifted. LP and D are driven accordingly, and an easy-to-read display screen that does not flicker due to afterimages is generated.

<Embodiment> FIG. 1 shows an information display device 1 according to an embodiment of the present invention.
The figure shows the situation in which it is installed in a taxi.

This information display device 1 is installed at the rear of a vehicle 2, and the screen of the display 4 is positioned and fixed with the screen facing the rear window 3 so that the displayed contents can be confirmed from the rear of the vehicle 2.

FIG. 2 shows a specific example of the display 4, which is constructed by arranging a plurality of display panels 5 in a line. Each display panel 5 has a large number of holes, and a matrix of light emitting points 6 (for example, 16 rows x 16 columns) is formed by incorporating a green LED and a red LED in each hole. .

FIG. 3 shows an example of the configuration of the drive circuit section 7 for causing the display 4 to perform a display operation.

This drive circuit section 7 includes a matrix circuit 8 and three drivers 9.10.11 provided for each display panel 5, and scans the entire display screen to determine which light-emitting point 6 is to be lit. drives the color LED and the light emitting point 60
The lighting positions are sequentially shifted. All green-emitting LEDs and all red-emitting LEDs are individually connected in a matrix to form the matrix circuit 8, and the green-emitting LEDs are connected to drivers 9 and 1o, and the red-emitting LEDs are connected to drivers 9 and 1o. 11, respectively.

The driver 9 receives a rearaddress signal from a control circuit section 12, which will be described later, and outputs a row selection signal S8 for sequentially activating the rows of the matrix circuit 8. Each driver 10.11 also includes a shift register, with one driver 10 receiving the green display data signal DTG and the other driver 10 receiving the green display data signal DTG.
1 is a red display data signal DT, each is input in series and shifted, and each bit data is output in parallel. In addition, each driver 10.11 receives a display enable signal EN, a latch signal LA, and a clock signal CK from the control circuit section 12.
is input. Display enable signal EN instructs lighting operation and smoke extinguishing operation. Latch signal LA latches the contents of the shift register. The clock signal CK provides timing for shifting the shift register.

FIG. 4 shows the timing of generation of the row selection signals S0 to SIS. In the figure, ts is the start point of scanning one screen of display information, and JtE is the end point of the scanning. T3
is the scanning time for one screen, and is made to coincide with the shift time. During the period T4A during which each of the row selection signals S0 to SI5 is on, as shown in the time chart of FIG. The contents of the register are latched, and the LED at the light-emitting point to be lit is driven.

FIG. 6 shows a specific example of the control circuit section 12.
A counter/timer controller 13 . Program RO
M15. Work RAM16. Data RAM17.1
8. A control unit 24 and the like are connected. Note that among the buses 19 to 21, 19 is a CPU data bus, and 20 is a CPU data bus.
indicates a CPU address bus, and 21 indicates a CPU control bus.

The program ROM 15 stores a conversion table TB, which will be described later, in addition to programs, and a work RAM 16.
will be used as a work area. Data RAM1
In 7.18, a plurality of types of display information, in this embodiment, a plurality of character information for advertisements are stored in separate areas.

Display information to be displayed is selected from among these plurality of display information, and the selected information is stored in the data RAM 17 or 18.
The data is then transferred to the work RAM 16. This display information includes display data and control data as shown in the data structure diagram of FIG. This control data includes display time, speed rank, etc.

In the figure, a crystal oscillator 22 generates a clock signal CK, and a memory backup unit 23 generates a program ROM.
15. Work RAM16. Data RAM17.18
to power back up.

The control unit 24 selects display information for the data RAM 17.18 under the control of the CPU 13 and controls the P/S conversion signal generator 27 and the P/S conversion units 28.29 through the control bus 30. The aforementioned address signal.

It generates and outputs control signals such as display enable signal EN and latch signal LA. One P/S conversion unit 2
The other P/S conversion unit 29 converts the red display data signal into parallel/serial data and outputs the green display data signal. The P/S conversion signal generator 27 inputs the clock signal CK from the crystal oscillator 22, generates a parallel/serial conversion signal, and supplies this to the P/S conversion units 28 and 29.

In the figure, an external signal interface unit 25 inputs various signals from the vehicle 2, and an external ROM interface unit 26 inputs kanji data for display from an external ROM (not shown).

FIG. 8 shows a control procedure by the control circuit unit 6. First, in step 1 (indicated by rsTIJ in the figure), the CPU 13 selects a speed rank R that defines a shift speed based on control data in display information to be displayed. , read. In the case of this embodiment, the speed rank R, is divided into eight stages from 0 to 7 (R0 to R,), and the scanning time T corresponding to the speed rank R8 is determined in advance and tabulated, and a conversion table TB is created. It is stored in the program ROM15.

FIG. 9 shows an example of the conversion table TB, in which predetermined scanning times are assigned to eight speed ranks R0 to R7. In this case, the scanning time is T for speed ranks R9 to R7.

is made to match the shift time as shown in Figure 4, but
For the slowest speed rank Re, the scanning time T3 is not made to coincide with the shift time, and a control method similar to the conventional one as shown in FIG. 11 is used.

Returning to FIG. 8, in step 2 it is determined whether speed rank R8 is the slowest speed rank R0, and if the determination is "No", in step 3 conversion table TB is
The scanning time T corresponding to the speed rank R8 is read out and set in the CPU 13 with reference to .

Next, in step 4, set the counter i in the CPU 13 to 0.
(in step 5, a timer is started. The counter i counts the scanning lines of the display screen, and the timer divides the scanning time for one line, that is, the scanning time T, into the number of lines (16 in this example). time).

In step 6, the row selection signal S selects the 0th row. is generated, and after the lighting position is shifted for the 0th row LED column, the LEDs to be lit are driven.

When the timer times up, it is determined in the next step 8 whether the value of the counter i has reached "I5", and in this case, the determination is "No", so in step 9 the value of the counter i is The content of is incremented, the process returns to step 5, the timer is started again, and the same procedure is executed.

In this way, when the value of the counter i reaches "15", it means that the entire display screen has been scanned, and the determination in step 8 becomes "YES", and in the next step 10, the transition operation for the display information is completed. Determine whether or not. If the determination is "NO", return to step 4,
The above procedure is repeated until step 10 becomes "YES".

The information display device 1 according to the present invention is not only installed in a taxi as in the above embodiment, but also installed in a game machine such as a slot machine 40 and its surroundings, for example, as shown in FIG. It is also possible to incorporate a circuit configuration.

<Effects of the Invention> As described above, in this invention, since the scanning time for one screen of display information is variably set according to the shift speed, the shift time Tt and the scanning time T for one screen can be made to match. is possible. Therefore, each of the light emitters is driven with the lighting position shifting at all times, and an easy-to-read display screen that does not flicker due to afterimages is generated, achieving the remarkable effect of achieving the purpose of the invention.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a vehicle equipped with the information display device of the present invention, FIG. 2 is a front view showing the configuration of the display, FIG. 3 is an electric circuit diagram showing an example of the configuration of the drive circuit section, and FIG. Figure and 5th
The figure is a time chart of the drive circuit section, FIG. 6 is a block diagram showing an example of the configuration of the control circuit section, FIG. 7 is an explanatory diagram showing the data structure of display information, and FIG. 8 is a control procedure of the control circuit section. 9 is an explanatory diagram showing an example of a conversion table, FIG. 10 is a front view showing a slot machine in which the present invention is implemented, and FIG. 11 is a time chart showing the operation of a conventional example. 1...Information display device 4...Display device 7...
...Drive circuit section 12...Control circuit section 13.
... CPU 15 ... Program ROM 16 ... Work RAM 17, 18 ... Data RAM

Claims (1)

[Claims] An information display device comprising a display, a memory, a drive circuit, and a control circuit, wherein the display has a display screen formed by arranging a large number of light emitters in a matrix. , the memory stores display information to be displayed on the display screen and a shift speed for shifting the display information on the display screen, and the drive circuit section scans the entire display screen of the display device. The control circuit unit drives each light emitting body to be lit according to the display information input from the memory and sequentially shifts the lighting position of the light emitter, and the control circuit unit displays one screen of display information according to the shift speed input from the memory. By setting the scanning time variably,
An information display device configured to control driving of a light emitting body and shifting of a lighting position by the driving circuit section.