DISPLAY DEVICE
A display device includes a plurality of pixels. One of the pixels includes a light emitting diode and a driving circuit coupled to the light emitting diode. A display frame period includes at least two emission periods. The light emitting diode emits light according to a data signal including a gray level in each of the at least two emission periods.
Latest Innolux Corporation Patents:
This application claims the priority benefit of U.S. provisional application Ser. No. 62/697,560, filed on Jul. 13, 2018. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
BACKGROUND 1. Field of the DisclosureThe present disclosure generally relates to display technology, and particularly to a driving mechanism to the pixels.
2. Description of Related ArtDisplay includes a large number of pixels to display an image in a display frame period. The pixel in an example includes a light emitting diode to emit a light. To drive the pixels to emit the light corresponding to the given gray level of color, a driving circuit is included to turn on the light emitting diode at an emission period in the display frame period, which usually is a time period between two scan signal pulses. In operation, each light emitting diode emits the light within an emission period as assigned. The light intensity corresponding to the gray level is determined by the data signal, which has carried the gray level as intended to the light emitting diode.
In general, an active matrix LED display with a hold drive scheme, gray level is controlled by driving current of LED device. As observed, the light emitting intensity is not stable or has large variation in low driving current range due to LED device characteristics. Semi-hold drive scheme may improve above issue by using larger driving current with short emission period. However, it has a risk of flicker due to the repetition of ON and OFF of light emitting, in an example.
How to improve the drive scheme without increasing data scan frequency is an issue to be looked into and improved.
SUMMARYThe disclosure provides a display device, wherein the driving schemes are proposed to improve the display quality.
In an embodiment, the disclosure provides a display device including a plurality of pixels. One of the pixels comprises: a light emitting diode and a driving circuit coupled to the light emitting diode. A display frame period includes at least two emission periods. The light emitting diode emits light according to a data signal comprising a gray level in each of the at least two emission periods.
In an embodiment, the disclosure further provides a display device A display device including a plurality of pixels. One of the pixels includes a light emitting diode and a driving circuit coupled to the light emitting diode. The plurality of pixels comprise a first pixel and a second pixel being abutting in a column direction of a pixel column, a row direction of a pixel row, or a diagonal direction, wherein the first pixel in the diagonal direction is an intersection pixel of one pixel column and one pixel row and the second pixel in the diagonal direction is an intersection pixel of another column and another pixel row respectively abutting to the one pixel column and the one pixel row. The first pixel corresponds to at least one first emission period in a display frame period, and the second pixel corresponds to at least one second emission period in the display frame period, the first pixel corresponds to at least one first emission period in a display frame period, and the second pixel corresponds to at least one second emission period in the display frame period. The at least one first emission period and the at least one second emission period are staggered.
In an embodiment, the disclosure further provides a display device A display device including a plurality of pixels. One of the pixels includes a light emitting diode and a driving circuit coupled to the light emitting diode. The plurality of pixels includes a first pixel and a second pixel abutting to the first pixel. The first pixel corresponds to at least one first emission period in a display frame period, and the second pixel corresponds to at least one second emission period in the display frame period. The at least one first emission period and the at least one second emission period are staggered.
The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.
The disclosure is directed to a display device with the proposed driving mechanism to cause the pixels of the display device to emit the light with at least less risk of the flicker phenomenon.
Several embodiments are provided for describing the disclosure but the disclosure is not just limited to the embodiments as provided.
In an embodiment, the light emitting diode 52 is not fully held on during the display frame period Tfm. The enable signal EM(n) allows setting the time period to actually turn on the light emitting diode 52. The enable signal EM(n) has the emission period 60 as indicated by Tem for a single duty cycle, in which the light emitting diode 52 is actually turned on to emit the light. However, in an embodiment of the disclosure, the emission period 60 in a single emission cycle as originally requested by the display device may be divided into at least two emission periods but the total amount of the at least two emission periods 62 remains the same as the emission period 60 with the amount of Tem. Thus, the emission cycle comprises at least one emission periods in the display frame period.
In an embodiment, the emission period 60 as requested is equally divided into two emission periods Tem/2 with half of emission period Tem, in which a certain variation within a range to have the emission periods Tem/2 is still acceptable, in which rage is within 10% variation or smaller. Further in an embodiment, the two emission periods 62 are uniformly distributed in the display frame period Tfm. The term “uniformly” or “equally” typically means within +/−10% of the stated value of emission period, more typically +/−5% of the stated value of emission period, more typically +/−3% of the stated value of emission period, more typically +/−2% of the stated value of emission period, more typically +/−1% of the stated value of emission period and even more typically +/−0.5% of the stated value of emission period. The stated value of the present disclosure is an approximate value and the others will be non-equally. When there is no specific description, the stated value of emission period includes the meaning of “about” or “substantially”.
Further in an embodiment, the emission period 60 is equally divided into four emission periods 64 with period of Tem/4 as a quarter of the emission period Tem. Likewise, the four emission periods 64 are uniformly distributed in the display frame period Tfm. The term “uniformly” typically means that all of the emission periods and the emission cycles in the display frame period are equally. And at least one of the emission periods and/or at least one of the emission cycles in the display frame period are not equally means non-uniformly.
As a result, the emission frequency in actual operation is increased. At least the flicker phenomenon can be reduced. The number of the emission periods can be set depending on the actual capability. The emission cycles may be not uniformly distributed in the display frame period Tfm, in an embodiment.
The embodiment above is with respect to one pixel itself. However, if the emission period 60 is not divided, a similar effect to the embodiments with dividing the emission period 60.
Even further in an embodiment,
The emission periods for the first pixel 130 and the second pixel 136 are separated in time. The first pixel 130 and the second pixel 136 are abutting two form another diagonal direction.
Likewise, the third pixel 132 and the fourth pixel 134 are controlled by the enable signals EM(n)_B and the enable signal EM(n+1)_A with the same effect to the first pixel 130 and the second pixel 136.
Even further in an embodiment, the features to divide the emission period 60 into multiple emission periods and to staggered the emission periods for the abutting two pixels may be combined together.
Further in an embodiment,
With the similar manner as described in
The disclosure has proposed to divide the emission period 60 as requested by the display device into multiple emission periods to increases the frequency to turn on the light emitting diode. The flicker phenomenon can be reduced.
Further, the emission periods for abutting pixels in row direction, column direction, or the diagonal direction can be arranged, in which the abutting pixels in row direction and column direction can also be realized abutting columns or abutting rows.
Even further, the combination for the above two manners may be made.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure cover modifications and variations of this disclosure provided they fall within the scope of the following claims and their equivalents.
Claims
1. A display device, comprising:
- a plurality of pixels, wherein one of the plurality of pixels comprises: a light emitting diode; and a driving circuit coupled to the light emitting diode;
- wherein a display frame period comprises at least two emission periods;
- wherein the light emitting diode emits a light according to a data signal comprising a gray level in each of the at least two emission periods.
2. The display device of claim 1, wherein the emission periods are equally in the display frame period with a variation of 10% or smaller off.
3. The display device of claim 1, wherein the emission periods are not equally in the display frame period with a variation within 10% to a stated value being equal.
4. The display device of claim 1, wherein the emission cycles are uniformly distributed in the display frame period with a variation within 10% to a stated value being uniform.
5. The display device of claim 1, wherein the emission cycles are non-uniformly distributed in the display frame period.
6. The display device of claim 1, wherein the at least two emission periods for abutting two of the plurality of pixels in a column direction, a row direction, or a diagonal direction are staggered.
7. A display device, comprising:
- a plurality of pixels, wherein one of the plurality of pixels comprises: a light emitting diode; and a driving circuit coupled to the light emitting diode;
- wherein the plurality of pixels comprises a first pixel and a second pixel being abutting in a column direction of a pixel column, a row direction of a pixel row, or a diagonal direction,
- wherein the first pixel corresponds to at least one first emission period in a display frame period, and the second pixel corresponds to at least one second emission period in the display frame period,
- wherein the at least one first emission period and the at least one second emission period are staggered.
8. The display device of claim 7, wherein the first pixel is one pixel in a first pixel column and the second pixel is one pixel in a second pixel column, the first pixel column is abutting to the second pixel column, wherein the first pixel column is abutting to the second pixel column.
9. The display device of claim 7, wherein the first pixel is one pixel in a first pixel row and the second pixel is one pixel in a second pixel row, the first pixel row is abutting to the second pixel row, wherein the first pixel row is abutting to the second pixel row.
10. The display device of claim 7, wherein the first pixel is one pixel in a first pixel row and in a first pixel column, wherein the second pixel is one pixel in a second pixel row and in a second pixel column, the first pixel row is abutting to the second pixel row, the first pixel column is abutting to the second pixel column;
- wherein the first pixel and the second pixel are staggered in a pixel array formed from the pixels,
- wherein the first pixel column is abutting to the second pixel column and the first pixel row is abutting to the second pixel row.
11. The display device of claim 10, wherein the pixels further comprise a third pixel and a fourth pixel being abutting in a diagonal direction, crossing with the diagonal direction formed by the first pixel and the second pixel, wherein the first pixel, the second pixel, the third pixel and the fourth pixel form a quadrilateral unit;
- wherein the third pixel corresponds to at least one third emission period in a display frame period, and the fourth pixel corresponds to at least one fourth emission period in the display frame period,
- wherein the at least one third emission period and the at least one fourth emission period are staggered.
12. The display device of claim 7, wherein the first pixel or the second pixel respectively comprises two of the first emission periods or the second emission periods.
13. A display device comprising a plurality of pixels, wherein one of the plurality of pixels comprises:
- a light emitting diode; and
- a driving circuit coupled to the light emitting diode,
- wherein the plurality of pixels comprises a first pixel and a second pixel abutting to the first pixel,
- wherein the first pixel corresponds to at least one first emission period in a display frame period, and the second pixel corresponds to at least one second emission period in the display frame period,
- wherein the at least one first emission period and the at least one second emission period are staggered.
14. The display device of claim 13, wherein the plurality of pixels comprises a third pixel abutting to the first pixel and a fourth pixel abutting to second pixel,
- wherein the third pixel corresponds to at least one third emission period in the display frame period, and the fourth pixel corresponds to at least one fourth emission period in the display frame period, and
- wherein the at least one third emission period and the at least one fourth emission period are staggered.
15. The display device of claim 14, wherein the first pixel and the third pixel are arranged along a row direction.
16. The display device of claim 15, wherein the first pixel comprises two the first emission periods.
17. The display device of claim 15, wherein the second pixel comprises two the second emission periods.
18. The display device of claim 14, wherein the first pixel and the third pixel are arranged along a column direction.
19. The display device of claim 14, wherein the first emission period and the third emission period pixel are staggered.
20. The display device of claim 14, wherein the second emission period and the fourth emission period pixel are staggered.
Type: Application
Filed: Dec 26, 2018
Publication Date: Jan 16, 2020
Applicant: Innolux Corporation (Miao-Li County)
Inventor: Hirofumi Watsuda (Miao-Li County)
Application Number: 16/232,081