JPS63104095A - Light emitting diode display device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a light emitting diode display device having a color tone and gradation control function.

[Conventional technology]

As a display device using an LED (9, photodiode), there is a conventional display device as shown in FIG. 5, for example. This is an example in which a display screen is constructed using a plurality of units. Each unit A and B has a data input section 1 such as a shift register into which display data is input, and an LED of a display section 2 according to the display data. A drive section 3 is provided to drive the. The display data thus inputted to the data input section 1 of unit A is sent to unit B, and then sequentially sent to the following units (not shown). When this display data is input to each unit, the drive section 3 is actuated directly by the data, and a lighting pulse signal is supplied to the LED of the display section 2 described above. At this time, if each display section 2 is provided with LEDs emitting light of red and green, for example, three-color display including a mixed color (M1 color) is possible.

[Problem that the invention seeks to solve]

However, in conventional LED display devices, when a display screen is constructed using multiple units as described above, each unit has different brightness and hue due to variations in chips, and this needs to be adjusted. Therefore, there was a problem that a good display screen could not be obtained.

The present invention has been made in view of these problems, and it is an object of the present invention to provide a light emitting diode display device that can adjust the brightness and hue and provide a good display screen.

[Means for solving problems]

The light emitting diode display device of the present invention includes a display data input section, a drive section that drives the light emitting diodes of the display section according to the display data, an input device for color tone setting, and an internal signal from this input device or an external signal. A control section that controls lighting time of the light emitting diode based on a signal is provided.

(Function) A lighting signal is output from the drive unit to the light emitting diode according to the display data, and the light emitting diode lights up as a result.
A predetermined display image is obtained as a whole. At this time, the control section controls the lighting time of each light emitting diode using an internal signal or an external signal from the input device, and adjusts its brightness and color.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the basic configuration of an LED display device according to the present invention, and the same reference numerals as in FIG. 5 refer to the same components. In the figure, 4 is an L that lights up by a pulse signal.
A control unit that controls the lighting time of the LED, and specifically controls the lighting time of the LED, that is, the ON time, by changing the pulse width of the pulse signal. This control section 4 is composed of a microcomputer, a logic circuit, etc., and controls the tone gradation of each unit by an internal signal from a tone setting input device 5 such as a dip switch inside the unit or by an external control number 13. . In addition, the display section 2 of each unit has two red and green
A plurality of LEDs containing individual chips are provided to form a three-color matrix screen.

In the LED display device configured as described above, when display data is input to each unit as in the conventional case, a lighting pulse signal is output from the drive unit 3 to the LED of the display unit 2 according to the data, and this pulse Each LE by signal
D lights up, and a predetermined display image is obtained as a whole in three colors. At this time, although the LEDs of each unit have differences in brightness and hue due to variations in chips, the control section 4 corrects this and displays a uniform brightness and hue.

Figure 2 shows how the color tone of the LED changes when red and green chips are turned on at the same time, and shows the waveform of the current flowing through each chip, that is, the waveform of the lighting pulse signal. . As shown in FIG. 2(a), if the on-time T of both the red and green chips is made equal, a normal orange display color can be obtained.

Also, as shown in Figure 2(b), if only the on-time of the red chip is shortened, an orange color close to green can be obtained, and conversely, as shown in Figure 2(c), only the on-time of the green chip is shortened. Then, an orange color close to red is produced.

In this way, the brightness and hue of the LED can be adjusted to any desired degree using the signal from the internal color tone setting input device 5 or the external control 18, so even when several units are used side by side, it is possible to It is possible to eliminate variations in brightness and hue between units, making it possible to obtain uniform image display, and also making it possible to change the brightness and hue of the entire screen. Furthermore, when using the device in a dark place, it is possible to avoid the waste of producing more brightness than necessary, and it is possible to save power. Furthermore, by adjusting the on-time of each single chip, it is possible to produce any hue from orange close to red to orange close to green.

FIG. 3 is a diagram showing a specific example of the configuration of the display section 2 of each unit. Here, a 16x16 pixel three-color matrix display screen is shown. Common electrode and each segment of red chip and green chip (SEG)
A single chip of each LED is connected to the g pole, and when a pulse signal based on display data is given to these electrodes from a microcomputer (not shown), each L
The ED lights up according to the data, and a predetermined display image is obtained as a whole. FIG. 4 shows the voltage waveform of the pulse signal supplied to the common electrode and the segment electrode and the current waveform flowing through the LED. As shown in the figure, when current flows through both the red and green chips, the LED emits orange light, and when current flows only through one of the red or green chips, the LED emits red or green light.

Also, as mentioned above, if the on time of the red chip is normal and the on time of the green chip is short, an orange color close to red will be obtained, and if the on time of the green chip is normal and the on time of the red chip is short, a green color will be obtained. Obtains an orange color close to .

Furthermore, if both on-times are shortened, a dark orange color can be obtained. Therefore, it is possible to reduce the brightness when using the device in a dark place, and it is possible to save power. Note that these changes in color tone and gradation can be continuously controlled by internal signals or external signals.

〔Effect of the invention〕

As explained above, according to the present invention, since a control section is provided that controls the lighting time (on time) of the LED using an internal signal or an external signal, the brightness and color tone can be adjusted due to variations in chips, etc. Even when a display screen is configured using multiple units, it is possible to obtain a good display screen with uniform brightness and one shade, and the color tone and gradation can be easily changed using internal and external signals, which saves money. This has the effect of saving electricity.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a light emitting diode display device according to the present invention, FIG. 2 is a current waveform diagram for explaining its operation, and FIG. 3 is a block diagram showing a specific configuration example of the display section of FIG. 1.
4 is a diagram showing the voltage waveform supplied to each electrode in FIG. 3 and the current waveform flowing through the LED, and FIG. 5 is a block diagram showing a conventional example. 1---Data input section 2...Display section 3...Drive section 4---Control section 5---Input device Fig. 1↓ 2nd Figure (a) Line-1 1,000-m- (b) Line-1-1: Figure 3 Figure 5

Claims (1)

[Claims] (1) An input section for display data, a drive section for driving the light emitting diodes of the display section according to the display data, and an input device for setting color tone, and the light emitting diodes are controlled by an internal signal or an external signal from the input device. 1. A light emitting diode display device comprising a control section for controlling lighting time of the light emitting diode display device.