TWI730839B - Display device - Google Patents

Abstract

A display device includes a plurality of over-driving information generators and a driving circuit. The over-driving information generators respectively correspond to a plurality different display wave-lengths. The over-driving information generators respectively receive a plurality of currently display data respectively corresponding to the display wave-lengths, and respectively compare the plurality of currently display data with a plurality of previously display data to respectively generate a plurality of over-driving information.

Description

Display device

The present invention relates to a display device, and particularly relates to a display device optimized for an overdrive mechanism.

In the technical field of display devices, when the display data is written to the display pixels, the data display operation of the display pixels has a certain delay time due to the capacitance on the display panel. Therefore, the conventional technical field proposes an overdrive mechanism to reduce the aforementioned delay time by further increasing (or decreasing) the voltage value of the driving voltage.

However, in the conventional technical field, no matter what color pixel corresponds to, the same overdrive voltage is used to perform the overdrive action. However, it is based on the fact that the human eye has different sensitivity to a variety of different colors. Therefore, the overdrive method of the prior art will produce ghosting phenomena generated by the display screens 110 and 120 as shown in FIGS. 1A and 1B, and cause the display quality to decrease. Among them, FIG. 1A and FIG. 1B are respectively the display images generated by the display device under different frame periods in the prior art.

The present invention provides a display device, which can effectively improve the display quality.

The display device of the present invention includes a plurality of overdrive information generators and driving circuits. The overdrive information generator corresponds to a plurality of different display wavelengths respectively. The overdrive information generator receives a plurality of current display data corresponding to the display wavelength, and compares the current display data and a plurality of previous display data respectively to generate a plurality of overdrive information respectively.

Based on the above, the display device of the present invention is provided with a plurality of overdrive information generators respectively corresponding to a plurality of display wavelengths. Through multiple independently operating overdrive information generators, different levels of overdrive actions can be performed for display pixels of different display wavelengths. Can effectively improve the quality of the display.

Please refer to FIG. 2, which is a schematic diagram of a display device according to an embodiment of the present invention. The display device 200 includes a plurality of overdrive information generators 211 to 21N and a driving circuit 220. The overdrive information generators 211~21N correspond to different display wavelengths, and the overdrive information generators 211~21N are used to receive the current display data IMG1~IMGN respectively, and the current display data IMG1~IMGN respectively correspond to the above-mentioned multiple displays. wavelength. The current display data IMG1~IMGN can be combined into a current display data IMG corresponding to a complete display pixel.

Under the condition that the overdrive mode is activated, the overdrive information generators 211-21N compare the received current display data IMG1~IMGN with multiple previous display data, and generate multiple overdrives respectively according to the comparison results. Information ODI1~ODIN. Here, the overdrive information generators 211-21N can receive the current display data IMG1~IMGN in the A-th frame period, and temporarily store the current display data IMG1~IMGN corresponding to the A-th frame period. In the A+1 frame period, the temporarily stored current display data IMG1~IMGN can be used as the previous display data and used to compare with the current display data received in the A+1 frame period (for example, the current display data respectively). Display data IMG1'~IMGN') for comparison to generate overdrive information ODI1~ODIN. The above A can be any positive integer.

It is worth noting that in this embodiment, the overdrive information generators 211-21N operate independently of each other. For example, the overdrive information generator 211 corresponds to the display wavelength of red, and the overdrive information generator 212 corresponds to the display wavelength of green, for example. The overdrive information ODI1 and ODI2 generated by the overdrive information generators 211 and 212 can be based on the sensitivity of the human eye to the red and green display wavelengths in addition to the difference between the current display data and the previous display data. Here, the generation methods of the overdrive information ODI1 and ODI2 of the overdrive information generators 211 and 212 are obviously independent of each other.

The driving circuit 220 is coupled to the overdriving information generators 211-21N. Under the condition that the overdrive mode is activated, the drive circuit 220 can receive overdrive information ODI1~ODIN respectively generated by the overdrive information generators 211~21N, and generate multiple overdrive voltages respectively according to the overdrive information ODI1~ODIN ODV, to perform over-driving actions for corresponding pairs of multiple display pixels. On the other hand, when the next frame cycle of the overdrive mode ends and the overdrive mode enters the normal mode, the drive circuit 220 receives the current display data IMG1~IMGN, and directly generates multiple data based on the current display data IMG1~IMGN. A driving voltage DRV is used to perform driving actions for the corresponding pairs of display pixels.

Incidentally, in the embodiment of the present invention, the overdrive information generators 211-21N may be multiple lookup tables, respectively. Each look-up table records a plurality of overdrive information to be selected, and each overdrive information to be selected corresponds to one of a plurality of currently displayed data index values and one of a plurality of previously displayed data index values. The lookup table can be as shown in Table 1 below:

Table 1: OGV1 OGV2 OGV3 …. OGVM PGV1 SD11 SD12 SD13 …. SD1M PGV2 SD21 SD22 SD23 …. SD2M PGV3 SD31 SD32 SD33 …. SD3M …. …. …. …. …. … PGVM SDM1 SDM2 SDM3 …. SDMM

Among them, Table 1 records multiple candidate overdrive information SD11~SDMM, and each candidate overdrive information SD11~SDMM respectively corresponds to one of the multiple currently displayed data index values OGV1~OGVM and multiple previously displayed data index values One of PGV1~PGVM. Among them, the candidate overdrive information SD11~SDMM on the diagonal of Table 1 can respectively correspond to the current display data index values OGV1~OGVM and the candidate overdrive information SD11~SDMM with the same value. Under such conditions, the overdrive action may not need to be executed. Among them, M is any positive integer.

In this embodiment, the currently displayed data index values OGV1 to OGVM in Table 1 can be sequentially increasing, and the previously displayed data index values PGV1 to PGVM can also be sequentially increasing. In the overdrive mode, the overdrive information generator corresponding to Table 1 (for example, the overdrive information generator 211) can find one of the current display data index values OGV1~OGVM based on the current display data (for example, the current display data Index value OGV2), and find one of the previously displayed data index values PGV1~PGVM based on the previously displayed data (for example, the previously displayed data index value PGV3), and correspondingly select the corresponding to-be-selected overdrive information SD23. In this way, the overdrive information generator 211 can output the overdrive information SD23 to be selected as the overdrive information ODI1.

It is not difficult to know from the content of Table 1 that in this embodiment, the overdrive information generator 211 can deal with the display gray level rising state where the current display data is greater than the previous display data, and the display gray level falling state where the current display data is smaller than the previous display data , Respectively generate different overdrive information ODI1.

Since the overdrive information generators 211-21N operate independently, the contents recorded in the look-up tables corresponding to the overdrive information generators 211-21N are different.

Please refer to FIG. 3A below. FIG. 3A is a schematic diagram of a display device according to another embodiment of the present invention. The display device 300 includes a timing controller 330, overdrive information generators 311, 312, and 313, a gamma voltage generator 340, a driving circuit 320, and a display panel 360. The overdrive information generators 311, 312, and 313 can be arranged in the memory 380 and implemented in the form of a lookup table. The timing controller 330 is coupled to the overdrive information generators 311, 312, and 313, and provides the current display data IMG to the overdrive information generators 311, 312, and 313 in the A-th frame period when the overdrive mode is activated .

The drive information generators 311, 312, and 313 respectively receive the current display data IMG1, IMG2, IMG3 corresponding to different display wavelengths from the current display data IMG. Among them, the drive information generators 311, 312, and 313 can respectively correspond to red wavelengths, green wavelengths, and blue wavelengths. The current display data IMG1, IMG2, and IMG3 are red, green, and blue display data, respectively. The drive information generators 311, 312, and 313 can compare the current display data of the current frame period with the previous display data of the previous frame period, and output overdrive information ODI1 to ODI3 accordingly. And provide overdrive information ODI1~ODI3 to the gamma voltage generator 340. The gamma voltage generator 340 can perform the gamma correction voltage conversion action according to the overdrive information ODI1~ODI3, and generate the overdrive voltage ODV1~ODV3 through the drive circuit 320 to perform the overdrive action on the display panel 360.

Then, in the A+1 frame period, the overdrive mode is turned off. The timing controller 330 can directly provide the current display data IMG to the gamma voltage generator 340. The gamma voltage generator 340 can perform the gamma correction voltage conversion action according to the current display data IMG1~IMG3 corresponding to different display wavelengths in the current display data IMG, and generate the driving voltages DRV1~DRV3 through the driving circuit 320. The display panel 360 performs general driving operations.

Incidentally, in the embodiment of the present invention, if the current display data IMG1~IMG3 are the same, the overdrive information ODI1 generated by the overdrive information generator 311 corresponding to the red wavelength is not less than the corresponding green under the rising display gray level. The overdrive information ODI2 generated by the overdrive information generator 312 of the wavelength; the above overdrive information ODI1 is greater than the overdrive information ODI3 generated by the overdrive information generator 313 corresponding to the blue wavelength; and the above overdrive information ODI3 is larger than the current display Information IMG1. On the other hand, when the display gray scale drops, the overdrive information ODI1 generated by the overdrive information generator 311 corresponding to the red wavelength is not greater than the overdrive information ODI2 generated by the overdrive information generator 312 corresponding to the green wavelength; corresponding to blue The overdrive information ODI3 generated by the color wavelength overdrive information generator 313 is not greater than the above-mentioned overdrive information ODI1; and the above-mentioned overdrive information ODI2 is smaller than the current display data IMG1.

Here, take the current display data which is the same as 128 (gray scale value) as an example, please refer to Table 2 below:

Table 2: Previously displayed data Red wavelength Green wavelength Blue wavelength Ascending state 0-128 a a b Descending state 255-128 c d e

According to Table 2, when the previous display data is between 0-128 and the current display data IMG1 to IMG3 is 128, the drive information generators 311 to 313 can determine that the current overdrive action is the display gray level rising state. The drive information generators 311 to 313 can generate overdrive information ODI1 to ODI3 as a, a, and b, respectively. Among them, a>b>128. In addition, when the previous display data is between 255-128, and the current display data IMG1 to IMG3 is 128, the drive information generators 311 to 313 can determine that the current overdrive action is a display gray scale decline state. The drive information generators 311 to 313 can generate overdrive information ODI1 to ODI3 as c, d, and e, respectively. Among them, 128> d >= c, and c and e may be the same, or c and e may be close to each other and may have an offset value. The above offset value can be adjusted by the designer according to the actual state, and there is no certain limit.

It is worth mentioning that the memory 380 may be embedded in the timing controller 330, or it may also be provided outside the timing controller 330. When corresponding to different types of display panels 360, the memory 380 can be replaced, or the content in the memory 380 in the timing controller 330 can be updated, which is more convenient in product implementation. In addition, since the drive information generators 311, 312, and 313 operate independently, engineers can replace any of the drive information generators 311, 312, and 313 without changing the design of the timing controller 330. Reduce the cost of products.

Incidentally, the driving circuit 320 is a source driving circuit, and can be implemented using a source driving circuit well known to those skilled in the art. In addition, the gamma circuit generator 340 can be designed according to the gamma characteristic curve of the display panel, and the gamma circuit generator 340 can be implemented by applying a gamma correction circuit well known to those skilled in the art. There are no specific restrictions. In addition, the display panel 360 of the embodiment of the present invention may be a liquid crystal display panel, or other types of display panels known to those with ordinary knowledge in the art, and there is also no specific limitation.

Please refer to FIG. 3B below. FIG. 3B is a schematic diagram of a partial circuit of the display device of the embodiment of FIG. 3A of the present invention. Among them, the display device 300 further includes a buffer circuit 390. The buffer circuit 390 is coupled between the timing controller 330 and the overdrive information generators 311-313. Among them, in a frame period, the buffer circuit 390 can receive the current display data IMG provided by the timing controller 330, and temporarily store the current display data IMG1 to IMG3 therein. In the next frame period, the display data IMG1~IMG3 originally stored in the buffer circuit 390 become the previous display data PIMG1~PIMG3. The buffer circuit 390 also provides the previous display data PIMG1~PIMG3 to the overdrive information generators 311~313, respectively. At this time, the overdrive information generators 311 to 313 receive the currently displayed data IMG1 to IMG3, respectively. The overdrive information generators 311 to 313 can generate overdrive information ODI1 to ODI3 by comparing the previously displayed data PIMG1 to PIMG3 and the currently displayed data IMG1 to IMG3, respectively.

Please note here that the buffer circuit 390 may be provided in the timing controller 330 or outside the timing controller 330. Alternatively, the buffer circuit 390 can be divided into three parts and disposed in the overdrive information generators 311 to 313, respectively.

Please refer to FIGS. 4A, 4B, 5A, and 5B below. FIGS. 4A, 4B, 5A, and 5B are schematic diagrams of display screens generated by a display device according to an embodiment of the present invention. Among them, in different frame periods, when the overdrive mode is in a state where the gray level is rising, in the embodiment of the present invention, as shown in FIG. 4A and FIG. 4B, the ghosting phenomenon on the display screens 410 and 420 generated by the display device is almost non-existent. exist. Similarly, in different frame periods, when the overdrive mode is in a state where the gray scale is reduced, in the embodiment of the present invention, the ghost phenomenon in the display screens 510 and 520 generated by the display device in FIG. 5A is compared with that in FIG. 1A and FIG. The display screens 110 and 120 of FIG. 1B are also greatly improved.

In summary, the present invention provides an overdrive information generator corresponding to different display wavelengths, and thereby generates a plurality of overdrive information. Through the independent operation of the overdrive information generator, the ghosting phenomenon in the display screen generated by the display device can be greatly eliminated, and the quality of the display can be improved.

110, 120, 410, 420, 510, 520: display screen 200, 300: display device 211~21N, 311~313: Overdrive information generator 220, 320: drive circuit 340: Gamma voltage generator 330: Timing Controller 360: display panel 380: memory 390: snubber circuit IMG, IMG1~IMGN, IMG1’~IMGN’: currently displayed data ODI1~ODIN: Overdrive information ODV, ODV1~ODV3: Overdrive voltage DRV, DRV1~DRV3: drive voltage PIMG1~PIMG3: Previously displayed data

FIG. 1A and FIG. 1B respectively show the display images generated by the display device under different frame periods in the prior art. FIG. 2 is a schematic diagram of a display device according to an embodiment of the invention. FIG. 3A is a schematic diagram of a display device according to another embodiment of the invention. 3B is a schematic diagram of a part of the circuit of the display device of the embodiment of FIG. 3A of the present invention. 4A, FIG. 4B, FIG. 5A, and FIG. 5B are schematic diagrams of display screens generated by the display device according to the embodiment of the present invention.

200: display device

211~21N: Overdrive information generator

220: drive circuit

IMG, IMG1~IMGN, IMG1’~IMGN’: currently displayed data

ODI1~ODIN: Overdrive information

ODV: Overdrive voltage

DRV: drive voltage

Claims (10)

A display device includes: a plurality of overdrive information generators, respectively corresponding to a plurality of different display wavelengths, respectively receiving a plurality of current display data corresponding to the display wavelengths, and respectively comparing the current display data and a plurality of previous display data , To generate a plurality of overdrive information respectively, the overdrive information generators include a first overdrive information generator, a second overdrive information generator, and a third overdrive information generator; and a drive circuit, Coupled to the overdriving information generators, generating overdriving voltages respectively according to the overdriving information, and performing overdriving actions for corresponding pairs of display pixels according to the overdriving voltages, wherein the The overdrive information generators operate independently of each other. When the corresponding current display data is greater than each of the previous display data, and the current display data are all the same, the first overdrive information generator generates a first The overdrive information is not less than a second overdrive information generated by the second overdrive information generator, the first overdrive information is greater than a third overdrive information generated by the third overdrive information generator, and the third overdrive information The drive information is larger than the current display data. The display device according to claim 1, wherein the overdrive information generators are respectively a plurality of different lookup tables, and each lookup table records a plurality of overdrive information to be selected, and each of the overdrive information to be selected corresponds to a plurality of One of the currently displayed data index values and one of the multiple previously displayed data index values. The display device according to claim 1, wherein the overdrive information generators include the first overdrive information generator and the second overdrive information generator And the third overdrive information generator corresponds to the red display wavelength, the green display wavelength, and the blue display wavelength, respectively. The display device according to claim 1, wherein when each of the corresponding current display data is smaller than each of the previous display data, and the current display data are all the same, a first pass generated by the first overdrive information generator The drive information is not greater than a second overdrive information generated by the second overdrive information generator, and a third overdrive information generated by the third overdrive information generator is not greater than the second overdrive information, and the first overdrive information The second driving information is smaller than the current display data. The display device according to claim 2, which further includes: a timing controller coupled to the overdrive information generators, and respectively provides the current display data and the previous display data to the overdrive information generators And a gamma generating circuit for providing a plurality of gamma voltages to the driving circuit. The display device according to claim 5, further comprising: a buffer circuit coupled between the timing controller and the overdrive information generators for temporarily storing the previous display data. The display device according to claim 5, wherein the overdrive information generators are arranged in at least one memory. The display device according to claim 7, wherein the at least one memory is built in the timing controller or externally connected to the timing controller. The display device according to claim 1, wherein the display wavelengths include red wavelengths, green wavelengths, and blue wavelengths. A display device includes: a plurality of overdrive information generators, respectively corresponding to a plurality of different display wavelengths, respectively receiving a plurality of current display data corresponding to the display wavelengths, and respectively comparing the current display data and a plurality of previous display data , To generate a plurality of overdrive information respectively, the overdrive information generators include a first overdrive information generator, a second overdrive information generator, and a third overdrive information generator; and a drive circuit, Coupled to the overdriving information generators, generating overdriving voltages respectively according to the overdriving information, and performing overdriving actions for corresponding pairs of display pixels according to the overdriving voltages, wherein the The overdrive information generators operate independently of each other. When the corresponding current display data is smaller than each of the previous display data, and the current display data are all the same, the first overdrive information generator generates a first An overdrive information is not greater than a second overdrive information generated by the second overdrive information generator, and a third overdrive information generated by the third overdrive information generator is not greater than the second overdrive information, and The second overdrive information is smaller than each of the currently displayed data.

Images