CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2017-0148279, filed on Nov. 8, 2017 in the Korean Intellectual Property Office (KIPO), the contents of which are incorporated herein in its entirety by reference.

BACKGROUND

1. Field

Aspects of example embodiments relate generally to a display device.

2. Description of the Related Art

Flat panel display (FPD) devices are widely used as a display device of electronic devices because FPD devices are relatively lightweight and thin compared to cathode-ray tube (CRT) display devices. Examples of FPD devices are liquid crystal display (LCD) devices, field emission display (FED) devices, plasma display panel (PDP) devices, and organic light emitting display (OLED) devices. The OLED devices have been spotlighted as next-generation display devices because the OLED devices have various advantages such as a wide viewing angle, a rapid response speed, a thin thickness, low power consumption, etc. An over driving method that compensates a driving data of a first frame may be utilized to prevent the brightness of the first frame from decreasing when brightness is changed.

The above information disclosed in this Background section is only for enhancement of understanding of the background and therefore it may contain information that does not constitute prior art.

SUMMARY

Aspects of example embodiments relate generally to a display device. For example, aspects of some example embodiments of the present inventive concept relate to a display device and a method for generating compensating data of the same.

Some example embodiments include a display device capable of improving display quality.

Some example embodiments include a method for generating a compensating data of the display device capable of improving display quality.

According to some example embodiments of the present invention, a display device includes: may include a display panel including a plurality of data lines, a plurality of gate lines, and a plurality of pixels and a compensating data generator configured to sense a sensing driving current of the pixel in a Nth frame and a target driving current of the pixel in a (N+M)th frame, and to calculate an over driving data that allows the sensing driving current to be the same with the target driving current by changing a data voltage of the Nth frame when a sensing image having a first grayscale in a (N−1)th frame and having a second grayscale in the Nth frame and the (N+M)th frame, where the N is an integer greater than or equal to 2, and M is an integer greater than or equal to 1.

In example embodiments, the compensating data generator may generate the plurality of over driving data by changing a grayscale value of the first grayscale and a grayscale value of the second grayscale, and generates an over driving lookup table (LUT) based on the plurality of over driving data.

In example embodiments, a grayscale value of the first grayscale may be lower than a grayscale value of the second grayscale.

In example embodiments, the compensating data generator may include a sensing image generator configured to generate a sensing image data corresponding to the sensing image, a feedback controller configured to sense the sensing driving current and the target driving current, to provide an over driving voltage to the data line of the display panel in the Nth frame when the sensing driving current is lower than the target driving current, and to provide the providing number of the over driving voltage to a memory when the sensing driving current is higher than or equal to the target driving current, the memory configured to store the providing number of the over driving voltage provided from the feedback controller, and an over driving lookup table generator configured to calculate the over driving data based on the providing number of the over driving voltage and to generate an over driving lookup table based on the over driving data.

In example embodiments, the feedback controller may perform a feedback loop that provides the over driving voltage to the data line of the driving panel until the sensing driving current is the same with the target driving current.

In example embodiments, the over driving voltage may have a voltage level corresponding to a predetermined reference grayscale.

In example embodiments, the over driving data may be calculated by adding a multiplying value of the reference grayscale by the proving number to the second grayscale.

In example embodiments, the feedback controller may include a first converter configured to convert the sensing driving current to a first digital signal and to convert the target driving current to a second digital signal, a comparator configured to the first digital signal to the second digital signal and to output a comparing result as an output signal, and a second converter configured to convert the output signal to an analog signal and to output the analog signal as the over driving voltage.

In example embodiments, the comparator may output a low level signal when the first digital signal is higher than or equal to the second digital signal, and output a high level signal when the first digital signal is lower than the second digital signal.

In example embodiments, the first converter may include an integrator configured to convert the sensing driving current to a sensing driving voltage and to convert the target driving current to a target driving voltage, and an analog-digital converter configured to convert the sensing driving voltage to the first digital signal and to convert the target driving voltage to the second digital signal.

In example embodiments, the second converter may include a digital-analog converter configured to convert the output signal of the comparator to an analog signal and an amplifier configured to amplify the analog signal to the over driving voltage and provide the over driving voltage to the data line.

In example embodiments, the display panel may include a display area and a non-display area, and the compensating data generator may calculate the over driving data of the pixels in the display area.

In example embodiments, the display panel includes a display area and a non-display area, and the compensating data generator calculates the over driving data of dummy pixels in the non-display area.

According to an aspect of example embodiments, a method for generating a compensating data of a display device may include a step of displaying a sensing image that has a first grayscale in a (N−1)th frame and a second grayscale in a Nth frame and a (N+M)th frame on a display panel, where the N is an integer greater than or equal to 2, and the M is an integer greater than or equal to 1, a step of sensing a sensing driving current of pixels included in the display panel in the Nth frame of the sensing image, a step of sensing a target driving current of pixels included in the display panel in (N+M)th frame of the sensing image, a step of comparing the sensing driving current to the target driving current, a step of providing an over driving voltage to the pixels in the Nth frame when the sensing driving current is lower than the target driving current, and a step of calculating an over driving data based on the providing number of the over driving voltage when the sensing driving current is higher than or equal to the target driving current.

In example embodiments, a method for generating a compensating data of a display device may further include a step of changing the first grayscale and the second grayscale and a step of generating an over driving lookup table based on the over driving data.

In example embodiments, a grayscale value of the first grayscale may be lower than a grayscale value of the second grayscale.

In example embodiments, the over driving voltage may have a voltage level corresponding to 1 grayscale.

In example embodiments, a method for generating a compensating data of a display device may further include a step of performing a feedback loop that provide the over driving voltage to data lines included in the display panel until the sensing driving current is the same with the target driving current.

Therefore, a display device and a method for generating compensating data may improve display quality of the display device by sensing the driving current of a pixel, determining an over driving data of a first frame using a feedback loop, and generating an over driving lookup table based on the over driving data when luminance of the display panel is changed. Further, the optimized over driving lookup table may be generated regardless of a deviation of a display panel because the over driving lookup table is generated by the display device. Further, a manufacturing time for generating the over driving lookup table in a manufacturing process may be reduced because the over driving lookup table is generated after shipment of the display device.

