CN1841450A - Display brightness adjusting method - Google Patents
Display brightness adjusting method Download PDFInfo
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- CN1841450A CN1841450A CN 200510056876 CN200510056876A CN1841450A CN 1841450 A CN1841450 A CN 1841450A CN 200510056876 CN200510056876 CN 200510056876 CN 200510056876 A CN200510056876 A CN 200510056876A CN 1841450 A CN1841450 A CN 1841450A
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Abstract
The brilliance method for a display comprises: providing multiple saturated contrast voltages; calculating to every voltage to obtain the display voltage; calculating all of the saturated contrast voltage, share voltage and display voltage to obtain the feed-through voltage; calculating the feed-through and saturated voltages to obtain the liquid crystal capacitor value; finally, obtaining the optimal contrast voltage. This invention saves time and cost, and can improve display level.
Description
Technical field
The present invention relates to a kind of brightness adjusting method of display, and is particularly related to and a kind ofly adjusts the anti-liquid crystal capacitance value that pushes away each contrast of feed-trough voltage of gained with briliancy, with the brightness adjusting method of the display that obtains optimization contrast voltage.
Background technology
The human dynamic image that can see the earliest is the film of documentary film kenel.From then on, the invention of cathode-ray tube (CRT) (Cathode Ray Tube is called for short CRT) successfully derives business-like televisor, and becomes the household electrical appliances device of each family's indispensability.Along with development of science and technology, the application of CRT expands to the desktop monitor in the computer industry again, and make the CRT scene nearly many decades for a long time.But the made all types of displays of CRT all face the problem of radiant rays, and because the structure of internal electron rifle, and make that display is bulky and take up space, so be unfavorable for thin typeization, lightweight and maximization.
Since above-mentioned problem, and make the researchist start to develop so-called flat-screen CRT monitor (Flat Panel Display).This field comprises LCD (Liquid CrystalDisplay, abbreviation LCD), Field Emission Display (Field Emission Display, abbreviation FED), vacuum fluorescent display (Vacuum Fluorescent Display, abbreviation VFD), Organic Light Emitting Diode (Organic Light Emitting Diode, be called for short OLED) and plasma display (Plasma Display Panel is called for short PDP).Wherein, PDP is because the visual angle, image quality is good and be beneficial to the advantage of maximization etc., and often apply to Digital Television in, its market enormously potential.
In present technology, utilize simulation software modulation contrast voltage can save new machine development time and cost, it is closely bound up to simulate required major parameter and pixel design, removes liquid crystal capacitance value (C
LC) outside, all the other parameters are all definite after pixel design is finished, the liquid crystal capacitance value because of with the relating to parameters of liquid crystal, so must consider the influence of material behavior.
Different liquid crystal has the relation of different percent of pass-display voltage (T-V) and liquid crystal capacitance value-display voltage (C-V), tradition twisted-nematic (TN) type liquid crystal pixel is relatively simple for structure, therefore can make test cell (test cell), and inject liquid crystal to measure the T-V and the C-V of liquid crystal, utilize the electric capacity computing formula again:
The liquid crystal capacitance value of conversion dot structure.Wherein, ε
0Be vacuum dielectric coefficient (being a fixed value 8.85e-14F/cm), ε
rBe that (different liquid crystal has different ε to the liquid crystal dielectric coefficient
rValue), A is the shared total area of liquid crystal capacitance, and d is the liquid crystal cells interval.
Please refer to Fig. 8, this figure is a kind of flow chart of steps of brightness adjusting method of known display.In technique known, as mentioned above, when making test cell, measured the T-V and the C-V curve of liquid crystal.In technique known, it at first does computing to character used in proper names and in rendering some foreign names agate (Gamma) curve, and the percent of pass (T) that obtains each contrast (s802).
Secondly, obtain the pairing display voltage (s804) separately of percent of pass of each contrast according to percent of pass-display voltage (T-V) curve.Then, then obtain the pairing liquid crystal capacitance value of the display voltage (C of each contrast according to liquid crystal capacitance value-display voltage curve
LC) (s806).At last, then the liquid crystal capacitance value of each contrast is done analog computation, and obtain the positive and negative polarity optimization contrast voltage (s808) of AC driving of modulation the best of each contrast.
Comprehensive the above because the test cell structure of at present general TN type liquid crystal from bottom to top is glassy layer, indium tin oxide layer (ITO), LC layer, indium tin oxide layer and glassy layer successively.Therefore, along with the demand of panel size and TV panel increases day by day, the wide viewing angle The Application of Technology trend that is inevitable.Yet the pixel design of wide viewing angle technology is not simple like the TN type, multizone homeotropic alignment (Multi-Domain Vertical Alignment for example, be called for short MVA) prominent point (bump) or slit (slit) structure are arranged, must consider its width, space and height when wherein designing.Designs such as in-plane translative mode (in-plane switching mode is called for short IPS) transverse electric field have more more complicated parameter and combination, therefore are difficult for obtaining the liquid crystal capacitance value by making test cell.
Summary of the invention
The brightness adjusting method that the purpose of this invention is to provide a kind of display, it adjusts the anti-liquid crystal capacitance value that pushes away each contrast of feed-trough voltage of gained with briliancy, so can save new machine development time and cost.
A further object of the present invention provides a kind of brightness adjusting method of display, and it is by analog-modulated optimization contrast voltage, so that positive display voltage can equal negative display voltage.
The present invention proposes a kind of brightness adjusting method of display, a plurality of contrasts that this brightness adjusting method provides display separately saturated contrast voltage when the center briliancy is saturated.Secondly, the saturated contrast voltage of each contrast is calculated, and obtain the display voltage of each contrast.Then, saturated contrast voltage, common voltage and the display voltage of each contrast are calculated, and obtained the feed-trough voltage of each contrast.Then, the feed-trough voltage and the saturated contrast voltage of each contrast is calculated, and obtain the liquid crystal capacitance value of each contrast.At last, the liquid crystal capacitance value of each contrast is done analog computation, and obtain the optimization contrast voltage of each contrast.
Described according to preferred embodiment of the present invention, this brightness adjusting method also comprises the display voltage of each contrast is calculated, and obtains the percent of pass of each contrast.
Described according to preferred embodiment of the present invention, the contrast that display is provided separately step of saturated contrast voltage when the center briliancy is saturated comprises with a direct current driven display, secondly, is provided as the common voltage of fixed value.Then, measure the saturated contrast voltage of each contrast respectively.
The present invention reintroduces a kind of brightness adjusting method of display, and this brightness adjusting method comprises the saturated contrast voltage of a contrast when the center briliancy is saturated that display is provided.Secondly, saturated contrast voltage is calculated, and obtain display voltage.Then, saturated contrast voltage, common voltage and display voltage are calculated, and obtained feed-trough voltage.Then, feed-trough voltage and saturated contrast voltage are calculated, and obtain the liquid crystal capacitance value.At last, the liquid crystal capacitance value is done analog computation, and obtain optimization contrast voltage.
Described according to preferred embodiment of the present invention, saturated contrast voltage comprises high voltage (Vsh) and low-voltage (Vsl).
The present invention is because of adopting the anti-liquid crystal capacitance value that pushes away each contrast of feed-trough voltage of adjusting gained with briliancy, therefore the substitution simulation can be tried to achieve each contrast voltage, simulation result is similar to the contrast voltage of the last modulation in loop, so not only can save new machine development time and cost, also can pass through analog-modulated optimization contrast voltage, show grade to reduce flicker and to promote.
For above and other objects of the present invention, feature and advantage can be become apparent, preferred embodiment cited below particularly, and conjunction with figs. are described in detail below.
Description of drawings
Fig. 1 is the flow chart of steps according to the brightness adjusting method of a kind of display of a preferred embodiment of the present invention.
Fig. 2 is the synoptic diagram according to the briliancy measuring appliance of a kind of display of a preferred embodiment of the present invention.
Fig. 3 A is the black contrast briliancy synoptic diagram according to a kind of face plate center briliancy measurement result of a preferred embodiment of the present invention.
Fig. 3 B is the white contrast briliancy synoptic diagram according to a kind of face plate center briliancy measurement result of a preferred embodiment of the present invention.
Fig. 4 is a kind of liquid crystal drive waveform synoptic diagram according to a preferred embodiment of the present invention.
Fig. 5 is a kind of feed-trough voltage-display voltage curve synoptic diagram according to a preferred embodiment of the present invention.
Fig. 6 is a kind of percent of pass-display voltage curve synoptic diagram according to a preferred embodiment of the present invention.
Fig. 7 is a kind of liquid crystal capacitance value-display voltage curve synoptic diagram according to a preferred embodiment of the present invention.
Fig. 8 is a kind of flow chart of steps of brightness adjusting method of known display.
Main element Biao Ji Said is bright
20: the briliancy measuring appliance
202: signal generation device
204: display panels
206: measuring junction
208: measurement mechanism
302: black contrast voltage curve
304: white contrast voltage curve
S100～s116: each steps flow chart
S802～s808: each steps flow chart
Embodiment
For the explanation that makes present embodiment can be clearer, so at first please refer to Fig. 2 at this, this figure is the synoptic diagram according to the briliancy measuring appliance of a kind of display of a preferred embodiment of the present invention.In the present embodiment, this briliancy measuring appliance 20 comprises signal generation device 202, display panels 204, measuring junction 206 and measurement mechanism 208.Wherein, signal generation device 202 can for example be a power supply device also, and measurement mechanism 208 can for example be a computing machine, but all not as limit.
Then, please merge with reference to Fig. 1 and Fig. 2, Fig. 1 is the flow chart of steps according to the brightness adjusting method of a kind of display of a preferred embodiment of the present invention.
In the present embodiment, brightness adjusting method at first is a plurality of contrasts that display is provided separately saturated contrast voltage (s100) when the center briliancy is saturated.Wherein, being measured as of saturated contrast voltage changes signal generation device 202 with direct voltage drive display panels 204 (s102) into the method for alternating voltage driving display panels 204 originally, even also the high voltage of each contrast (Vsh) equals low-voltage (Vsl).
In preferred embodiment of the present invention, saturated contrast voltage comprises high voltage (Vsh) and low-voltage (Vsl).
Then, be provided as fixed value shared (common) voltage and give display panels 204 (s104).Then, measure the saturated contrast voltage (s106) of display panels 204 center briliancy when saturated with measuring junction 206.
Wherein, as shown in Figure 3A, when measuring the saturated contrast voltage of display panels 204 center briliancy, will have a minimum saturated contrast voltage, wherein, this minimum saturated contrast voltage can comprise the high voltage (Vsh) and low-voltage (Vsl) of black contrast.
And shown in Fig. 3 B, when measuring the saturated contrast voltage of display panels 204 center briliancy, will have the highest saturated contrast voltage, wherein, this highest saturated contrast voltage can comprise the high voltage (Vsh) and low-voltage (Vsl) of white contrast.The rest may be inferred, and the high voltage of all the other each contrasts and low-voltage all can obtain in this way.
Then, please continue, after obtaining the saturated contrast voltage of each contrast, can utilize by the saturated contrast voltage (Vsh and Vsl) of resulting formula among Fig. 4 and calculate, and the display voltage (Vd) that obtains each contrast (s108) each contrast with reference to Fig. 1.Formula can be expressed as:
Vsh＝Vcom+Vd+D′Vp
Vsl＝Vcom-Vd+D′Vp
Therefore, can obtain according to above two formula
Then, the saturated contrast voltage of each contrast, common voltage (Vcom) are calculated with display voltage, (s110), it can be expressed as can to utilize above two formula to obtain feedthrough (feedthrough) voltage (D ' Vp) of each contrast:
So, can obtain as shown in Figure 5 relation curve according to this feed-trough voltage and display voltage.
Then, the display voltage of 208 pairs of resulting each contrasts of measurement mechanism is calculated respectively, and obtains the percent of pass (s112) of the liquid crystal of each contrast.Therefore, can obtain as shown in Figure 6 percent of pass-display voltage (T-V) graph of relation equally.
Then, the feed-trough voltage and the saturated contrast voltage of each contrast is calculated, and obtain the liquid crystal capacitance value (C of each contrast
LC) (s114).Wherein, the liquid crystal capacitance value is to derive according to principle of charge conservation to learn, it can be as shown below:
Wherein, D ' Vp is a feed-trough voltage, and Vgh is the high voltage of grid, and Vgl is the low-voltage of grid, and Cgd is the electric capacity between transistorized gate-to-drain, and Cs is a storage capacitors.Therefore, under D ' Vp, Vgh, Vgl, Cgd and Cs are known situation, can learn liquid crystal capacitance value C
LC
So, according to C
LCCan obtain as shown in Figure 7 C-V relation curve with the value of D ' Vp.
In preferred embodiment of the present invention, the purpose of adjusting contrast voltage is to equal Vd-for the display voltage Vd+ that makes Fig. 4.
In the present embodiment, after obtaining the liquid crystal capacitance value of each contrast, it is made the optimization contrast voltage (s116) that analog computation can obtain each contrast.
In preferred embodiment of the present invention, as shown in table 1, after the equal substitution of all above-mentioned resulting parameters, can obtain the feed-trough voltage D ' Vp ' of three contrasts putting down in writing as table 1.D ' Vp is then for to adjust resulting feed-trough voltage according to briliancy.
Table 1
| White contrast | Middle contrast | Black contrast | |
| D’Vp | 0.875 | 0.99 | 1.07 |
| D’Vp’ | 0.815 | 0.990456 | 1.111827 |
Therefore, can learn by above-mentioned comparison, with the resulting feed-trough voltage of the described method of present embodiment with to adjust resulting feed-trough voltage with briliancy very close.
In sum, in the brightness adjusting method of display of the present invention, because of adjust the anti-liquid crystal capacitance value that pushes away each contrast of feed-trough voltage of gained with briliancy, therefore the substitution simulation can be tried to achieve each contrast voltage, simulation result is similar to the contrast voltage of the last modulation in loop, so not only can save new machine development time and cost, also can pass through analog-modulated optimization contrast voltage, show grade to reduce flicker and to promote.
Though the present invention discloses as above with preferred embodiment; right its is not in order to limit the present invention; the technician of any technical field that the present invention belongs to; without departing from the spirit and scope of the present invention; when can doing a little change and improvement, so protection scope of the present invention is as the criterion when looking the claim person of defining.
Claims (11)
1. the brightness adjusting method of a display is characterized in that comprising:
A plurality of contrasts that this display is provided separately saturated contrast voltage when the center briliancy is saturated;
This saturated contrast voltage to each above-mentioned these contrast calculates, and obtains the display voltage of each above-mentioned these contrast;
This saturated contrast voltage, common voltage and this display voltage to each above-mentioned these contrast are calculated, and obtain feedthrough (feedthrough) voltage of each above-mentioned these contrast;
This feed-trough voltage to each above-mentioned these contrast calculates with this saturated contrast voltage, and obtains the liquid crystal capacitance value of each above-mentioned these contrast; And
This liquid crystal capacitance value to each above-mentioned these contrast is done analog computation, and obtains the optimization contrast voltage of each above-mentioned these contrast.
2. the brightness adjusting method of display according to claim 1 is characterized in that also comprising that this display voltage to each above-mentioned these contrast calculates, and obtains the percent of pass of each above-mentioned these contrast.
3. the brightness adjusting method of display according to claim 1, above-mentioned these contrasts that it is characterized in that providing this display separately the step of this saturated contrast voltage when the center briliancy is saturated comprises:
With this display of direct voltage drive;
Be provided as this common voltage of fixed value; And
Measure this saturated contrast voltage of each above-mentioned these contrast respectively.
4. the brightness adjusting method of display according to claim 1 is characterized in that this saturated contrast voltage comprises high voltage (Vsh) and low-voltage (Vsl).
5. the brightness adjusting method of display according to claim 1, it is characterized in that this feed-trough voltage of each above-mentioned these contrast and this saturated contrast voltage are calculated, and this liquid crystal capacitance value of obtaining each above-mentioned these contrast is by being pushed away by the charge conservation theorem.
6. the brightness adjusting method of display according to claim 1 is characterized in that being applicable to the LCD of tool wide viewing angle.
7. the brightness adjusting method of a display is characterized in that comprising:
The saturated contrast voltage of a contrast when the center briliancy is saturated of this display is provided;
This saturated contrast voltage is calculated, and obtain display voltage;
This saturated contrast voltage, common voltage and this display voltage are calculated, and obtained feedthrough (feedthrough) voltage;
This feed-trough voltage and this saturated contrast voltage are calculated, and obtain the liquid crystal capacitance value; And
This liquid crystal capacitance value is done analog computation, and obtain optimization contrast voltage.
8. the brightness adjusting method of display according to claim 7 is characterized in that also comprising this display voltage is calculated, and obtains percent of pass.
9. the brightness adjusting method of display according to claim 7 is characterized in that providing the step of this saturated contrast voltage of this contrast when the center briliancy is saturated of this display to comprise:
With this display of direct voltage drive;
Be provided as this common voltage of fixed value; And
Measure this saturated contrast voltage of this contrast.
10. the brightness adjusting method of display according to claim 7 is characterized in that this saturated contrast voltage comprises high voltage (Vsh) and low-voltage (Vsl).
11. the brightness adjusting method of display according to claim 7 is characterized in that this feed-trough voltage and this saturated contrast voltage are calculated, and obtains this liquid crystal capacitance value by being pushed away by the charge conservation theorem.
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| CNB2005100568769A CN100433084C (en) | 2005-03-28 | 2005-03-28 | Display brightness adjusting method |
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| CNB2005100568769A CN100433084C (en) | 2005-03-28 | 2005-03-28 | Display brightness adjusting method |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101685609B (en) * | 2008-09-26 | 2011-07-27 | 比亚迪股份有限公司 | Method for improving display crosstalk and thinning in liquid crystal display |
| CN102708825A (en) * | 2012-05-31 | 2012-10-03 | 京东方科技集团股份有限公司 | Method and device for setting gamma reference voltage, driving circuit and display device |
| WO2014190615A1 (en) * | 2013-05-31 | 2014-12-04 | 京东方科技集团股份有限公司 | Method and apparatus for determining driving voltage |
| CN109872701A (en) * | 2019-04-22 | 2019-06-11 | 京东方科技集团股份有限公司 | Source electrode voltage adjusting method, display module and liquid crystal screen |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1180291C (en) * | 2000-03-14 | 2004-12-15 | 皇家菲利浦电子有限公司 | Twisted nematic liquid crystal display device with means for temperature compensation of operating voltage |
| JP2002351409A (en) * | 2001-05-23 | 2002-12-06 | Internatl Business Mach Corp <Ibm> | Liquid crystal display device, liquid crystal display driving circuit, driving method for liquid crystal display, and program |
| KR100729769B1 (en) * | 2001-06-18 | 2007-06-20 | 삼성전자주식회사 | Liquid crystal display |
| JP3906103B2 (en) * | 2002-03-25 | 2007-04-18 | 三洋電機株式会社 | Electroluminescence element and electroluminescence display device |
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2005
- 2005-03-28 CN CNB2005100568769A patent/CN100433084C/en active Active
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101685609B (en) * | 2008-09-26 | 2011-07-27 | 比亚迪股份有限公司 | Method for improving display crosstalk and thinning in liquid crystal display |
| CN102708825A (en) * | 2012-05-31 | 2012-10-03 | 京东方科技集团股份有限公司 | Method and device for setting gamma reference voltage, driving circuit and display device |
| US9171510B2 (en) | 2012-05-31 | 2015-10-27 | Boe Technology Group Co., Ltd. | Method and apparatus for setting gamma reference voltage, driving circuit and display apparatus |
| WO2014190615A1 (en) * | 2013-05-31 | 2014-12-04 | 京东方科技集团股份有限公司 | Method and apparatus for determining driving voltage |
| CN109872701A (en) * | 2019-04-22 | 2019-06-11 | 京东方科技集团股份有限公司 | Source electrode voltage adjusting method, display module and liquid crystal screen |
| CN109872701B (en) * | 2019-04-22 | 2021-10-01 | 京东方科技集团股份有限公司 | Source electrode voltage adjusting method, display module and liquid crystal screen |
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Effective date of registration: 20160816 Address after: The Marshall Islands Majuro Adger Island Road trust company Tektronix Tektronix Adger areas MH96960 Patentee after: Hao Chi intangible asset management Investment Limited Address before: Taiwan, Taipei, China Zhongshan North Road three paragraph twenty-two Patentee before: Chunghwa Picture Tubes Ltd. |
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Effective date of registration: 20161205 Address after: Hubei City, Wuhan Province, East Lake Development Zone, No. 666 high tech Road, biological city C5 Patentee after: Wuhan Hua Xing photoelectricity technology corporation, Ltd. Address before: The Marshall Islands Majuro Adger Island Road trust company Tektronix Tektronix Adger areas MH96960 Patentee before: Hao Chi intangible asset management Investment Limited |