KR100718962B1 - Projection Display Driving Apparatus - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high definition display apparatus, and more particularly, to an illumination system driving apparatus of a projection display using LEDs. In the display driving apparatus including a plurality of color light source units including one or more LED light sources according to the present invention, at least one of duty and amplitude of one or more LED light sources may be different from each other. A driving controller for generating a control signal for driving the LED light source to be different; A temperature processor for detecting a temperature of the LED light source and converting an amplitude and a duty of a pulse; And a light emitting unit for mounting the LED light source units of the plurality of colors. The present invention improves the luminance problem of a single LED by using multiple LEDs, and reduces the saturation of the color gamut of the LED by adjusting the amplitude and duty of the pulse. It was.

Projection Display, LED Light Source, Color Gamut

Description

Projection Display Driving Apparatus {Projection Display Driving Apparatus}             

1 is a view showing a configuration of a conventional LED lighting system

2 is a view showing a LED driving timing diagram according to the prior art;

FIG. 3 is a diagram illustrating a color gamut that is saturated in the prior art. FIG.

4 is a view showing a multi-LED driving apparatus according to the present invention;

5 is a multi-LED driving timing diagram according to the present invention;

6 is a view showing a reduction in saturation effect of a color gamut according to the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high definition display apparatus, and more particularly, to an illumination system driving apparatus of a projection display using LEDs.

Recently, various technologies have been developed with increasing interest in large screen and high-definition display devices. Projection televisions and projectors are the representative ones that have been developed and widely used as large-screen display devices.

Projection televisions and projectors commonly use light sources. Many kinds of lamps are used as light sources. The use of lamps has several problems.

Firstly, the lamp life is short.

Second, power consumption is high.

Third, there is a problem that the display element is thermally destroyed, that is, a cooling problem.

Recently, there is an attempt to introduce a new light source to improve the problem of using such a light source. Among them, LEDs, that is, light emitting diodes, are used as new light sources.

Since LEDs have a long lifespan and do not emit light due to heat or discharge, they have a very fast lighting speed. In addition, since the efficiency of the electro-optical conversion is low, energy consumption can be reduced. Since there is no filament like a lamp, it has excellent impact resistance and does not break suddenly.

In addition, the LED has the advantage of miniaturization and thinning because the device itself is a very small circle. First of all, since the emission spectrum is narrow, it is advantageous to secure a monochromatic light source and to recognize visually.

As a monochromatic feature, there are attempts to use R (Red), G (Green), and B (Blue) LEDs as light sources. By using the three primary colors of light, various colors including white can be expressed.

1 is a view showing a configuration of a conventional LED lighting system.

As shown in the drawing, the display device controller in the related art uses one RGB LED to drive one LED for each clock through a pulse width modulation (PWM) control scheme. The PWM control refers to a method of adjusting a control value by adjusting a duty ratio of a pulse signal. Here, the duty ratio refers to the ratio of the time T high of the high signal to one period T.

LED driving reproduces various colors including white by using three primary colors of light. To this end, the display device controller drives one RGB LED for each clock through a pulse width modulation (PWM) control scheme.

2 is a view showing a LED driving timing diagram according to the prior art.

As shown, conventionally, it can be seen that the R, G, B LEDs are alternately driven during the period T. In this case, the controller may control the driving timing of the R, G, and B LEDs, such as a pulse occurrence frequency, by a pulse width modulation (PWM) control scheme. However, this LED driving method generates saturation because the color gamut of the LED is larger than the color gamut of the NTSC. That is, in the conventional LED driving, each single LED is driven through PWM control according to a control signal input to the controller as in the timing diagram of FIG. 2.

FIG. 3 is a diagram illustrating a color gamut that has been saturated in the prior art.

As described above, the LED driving method according to the prior art generates saturation because the color gamut of the LED is larger than the color gamut of the NTSC. The saturation of the color gamut may be an unwanted color beyond the color coordinates of the current NTSC.

That is, for example, in the prior art, the red (R) color of the NTSC is reproduced differently from the red (R) color of the LED, thereby causing a problem of reproducing a color that is not familiar to the user. In addition, the LED has a problem in that the output of the LED is changed according to the ambient temperature to change the color coordinates.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and improves the brightness problem of a single LED using multiple LEDs, and reduces the saturation effect of the LED color gamut by controlling the multiple LEDs. For the purpose of

DETAILED DESCRIPTION A detailed description of preferred embodiments of the present invention will now be described with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. The terms to be described below are terms defined in consideration of functions in the present invention, which may vary according to a user's intention or custom, and the definitions should be made based on the contents throughout the specification.

According to an embodiment of the present invention, a display display driving apparatus including a plurality of color light source units including one or more LED light sources may include a duty and amplitude of one or more LED light sources in each of the plurality of light source units. A driving controller configured to generate a control signal for driving the LED light source such that at least one of the amplitudes is different from each other; And a light emitting unit for mounting the LED light source units of the plurality of colors.

delete

In one embodiment of the present invention, it further comprises a temperature processing unit for converting the amplitude and the duty of the pulse by sensing the temperature of the LED.

In one embodiment of the present invention, the drive control unit is characterized in that it comprises a memory for storing the amplitude and the duty value according to the temperature.

In one embodiment of the present invention, the light emitting portion is characterized in that the metal PCB.

In one embodiment of the present invention, the temperature processor is characterized in that it comprises an analog-to-digital converter and a digital-analog converter.

According to another aspect of the present invention, there is provided a display driving apparatus including one or more LED light sources, including: a driving controller configured to control a duty and an amplitude of the LED light sources; A temperature processor configured to detect a temperature of the LED light source and convert an amplitude and a duty of a pulse; And it characterized in that it comprises a light emitting unit for mounting the LED light source.

In another embodiment of the present invention, the driving control unit may further include a memory for storing the amplitude and the duty value according to the temperature.

In another embodiment of the present invention, the temperature processor comprises an analog-to-digital converter and a digital-to-analog converter.

In another embodiment of the present invention, the light emitting portion is characterized in that the metal PCB.

4 is a view showing a multi-LED driving apparatus according to the present invention.

As shown in the drawing, the multi-LED driving apparatus according to the present invention includes a driving controller 100 and a light emitting unit 150.

The driving controller 100 includes a pulse and duty controller 110, a ROM table 120, an AD converter 130, and a DA converter 140.

The light emitting unit 150 according to the present invention is formed of a plurality of LEDs, that is, an LED array (LED ARRAY), it is characterized in that it is mounted on a metal PCB. The reason why it is composed of multiple LEDs is to realize colors that are difficult to express with a single LED light source alone. That is, the present invention is to implement a more natural color by emitting a plurality of LEDs overlapping each other.

In addition, when a plurality of LEDs emit light overlapping each other, luminance characteristics are improved as compared with light emission by only a single LED light source.

The reason for mounting the LED array on the metal PCB is to facilitate heat dissipation due to the characteristics of the LED whose light emission characteristics change with temperature. The present invention provides a method for solving the light emission characteristics according to the temperature change.

The pulse and duty controller 110 generates a control signal for driving the light emitting unit 150, that is, a pulse, and adjusts an amplitude and a duty of the pulse to obtain a desired output. The intensity and time of the brightness of the plurality of LED light sources are determined by the pulse generated by the pulse and duty controller 110.

The ROM table 120 which is a memory unit stores amplitude and duty values according to temperature.

The AD converter 130 senses the temperature of the light emitting unit 150 in real time and sets the amplitude and duty value according to the temperature stored in the ROM table 120, and then the pulse and duty controller 110. Pass the temperature data on.

The pulse and duty controller 110 outputs a PWM drive control signal by changing the amplitude and the duty.

The DA converter 140 performs current / voltage control according to the PWM drive control signal command of the pulse and duty controller 110. In the light emitting unit 150, each LED is driven according to each PWM control signal.

The pulse and duty controller 110 determines the compensation value of the LED according to the temperature according to the ROM table 120 which stores the amplitude and the duty value according to the temperature, and the amplitude and the duty through the current / voltage control. Determine.

5 is a timing diagram of multi-LED driving according to the present invention, and shows a case where a plurality of LEDs are simultaneously driven by pulses having different amplitudes.

In FIG. 5, the case where three R, G, B LED light sources are used as a some LED light source is shown, respectively.

As shown, when any one of the R, G, B LED light source is driven, it can be seen that the remaining light sources are also driven at the same time.

In this case, it can be seen that any one of the R, G, and B LED light sources becomes a main light source, and the remaining light sources become a sub light source. In this case, it can be seen that the saturation effect of the color gamut caused by a single LED light source is reduced. That is, when some of the light sources of R, G, and B overlap, the brightness is increased and more natural color is expressed as compared with the color expression using only a single light source.

As described above, the amplitude and duty values of the R, G, B LED light sources can be adjusted by the controller. Therefore, the controller controls the amplitude and duty values of the R, G, and B LED light sources for a desired output, and enables various colors to be expressed and luminance, as well as color gamut saturation, that is, NTSC. This prevents you from leaving the area. In other words, during the period T, the R, G, and B LED light sources are driven, respectively, to obtain a desired output according to the control signal of the controller.

6 is a view showing a reduction in the saturation effect of the color gamut according to the present invention.

As shown in the drawing, the controller controls the amplitude and duty values of the R, G, and B LED light sources to enable various colors to be expressed, and the color gamut is used to create a new saturation, that is, an NTSC area. It prevents it from falling out. The driving controller changes the driving frequency and the duty of the LEDs or applies pulses having different amplitudes to each LED, and determines the luminance of the LEDs by changing the duty and the amplitude. In addition, it is possible to simultaneously drive LEDs with different amplitudes to prevent color gamut saturation and to control the color gamut of the LEDs.

The technical spirit of the present invention has been described above with reference to the accompanying drawings, but this is by way of example only and not intended to limit the present invention. In addition, it is obvious that any person skilled in the art can make various modifications and imitations without departing from the scope of the technical idea of the present invention.

The present invention improves the luminance problem of a single LED using multiple LEDs as described above, and adjusts the amplitude and duty of the pulse to improve the saturation of the color gamut of the LED. It can be reduced.

Claims (6)

A display driving apparatus comprising a plurality of color light source units including one or more LED light sources. A driving controller configured to generate a control signal for driving the LED light source such that at least one of duty and amplitude of at least one LED light source is different in each of the plurality of light source units; And And a light emitting unit for mounting the LED light source units of the plurality of colors. delete The display driving apparatus of claim 1, further comprising a temperature processor configured to convert an amplitude and a duty of the pulse according to the sensed temperature. The display driving apparatus of claim 3, wherein the driving controller includes a memory configured to store an amplitude and a duty value according to temperature. The display driving apparatus of claim 1, wherein the light emitting unit is made of a metal PCB. The display driving apparatus of claim 3, wherein the temperature processor comprises an analog-digital converter and a digital-analog converter.

Images