201015528 ί 29311twf.doc/n 九、發明說明： 【發明所屬之技術領域】 本發明是有關於一種顯示器的驅動方法，且特別是有 關於一種將紅-綠-藍影像資料(R-G-B image data)轉換為紅 -綠-藍-白影像資料(R-G-B-W image data)之顯示器的驅動 方法。 ❿ 【先前技術】 具有南晝質、空間利用效率佳、低消耗功率、無辕射 4優越特性之液晶顯示器(Liquid Crystal Display，LCD)已 逐漸成為顯示器之主流。為滿足使用者的需求，各廉商均 致力於高色彩重現(color reproduction)技術的開發，而高色 彩重現技術的開發與液晶顯示器之背光源與彩色濾光膜的 色飽和度(color saturation)息息相關。 為了讓顯示器能夠有較佳的亮度表現，具有紅、綠、 藍、白四種子畫素之顯示器已被提出，此類型的顯示器雖 具有較佳的亮度表現’但色飽和度常會因為白色子晝素而 有所降低。詳言之，當顯示器在顯示純色（如紅色、綠色、 藍色）晝面時，若將白色子晝素開啟，將導致純色晝面色 飽和度明顯降低；反之，若不將白色子晝素開啟，亦容易 V致衫像不連續的視覺感受。因此，白色子書素的亮度控 制便成為此類型之顯示器在驅動時的重要考量因素之一。 換s之，如何在純色晝面的色飽和度與影像的連續性之間 找到平衡點，是此類型之顯示器亟待解決的問題之一。 5 201015528 j / 29311twf.doc/n 目前，Kodak公司以及Canon公司已分別在其美國專 利US 6,885,380號以及美國專利US 5,929,842號中提及如 何從紅-綠-藍影像資料(r_G_B image data)計算出白色子责 素的顯示資料(W display data)。然而，上述專利的目的皆 在於排除顯示影像發生鋸齒狀邊緣，其並未考慮顯示器之 色飽和度是否會下降。 ❹ 【發明内容】 ^本發明提供一種顯示器的驅動方法’其適於將紅_綠_ 藍影像資料轉換為紅-綠_藍_白影像資料。 本發明提出一種顯示器的驅動方法，其適於驅動一具 有紅色次晝素、綠色次畫素、藍色次晝素以及白色次晝素 示器，當輸入一紅_綠_藍影像資料至顯示器時，顯示 巧夠顯示-最大色域，而顯示器的驅動方法先於顯示器 所月b夠顯示的最大色域内，選定一目標色域。接著，將紅_ 影像資料轉換為一紅-綠-藍-白影像資料，以使顯示器 此夠顯示目標色域。之後，將紅-綠-藍-白影像資料輸入至 顯示器，以驅動顯示器。 在本發明之一實施例中，上述目標色域小於最大色 域。 在本發明之一實施例中，將紅_綠_藍影像資料轉換為 綠^藍-白影像資料的方法包括：當紅綠藍影像資料僅 =括單一純色的資料時，根據紅_綠_藍影像資料以及目標 ，計算出白色次晝素的一最大亮度，並令白色 -人旦素顯示一預設亮度[Wdefault，其中預設亮度 default 7 29311twf.doc/n 小於最大亮度LWmax;以及當紅-綠-藍影像資料包括多種 純色的資料時，根據目標色域以及不同的紅_綠_藍影像資 料，計算出白色次晝素的一對應亮度，並令白色次晝素顯 示對應亮度。 在本發明之一實施例中，上述之預設亮度LWdefault以 及白色次晝素所顯示的對應亮度是記錄於一對照表 (Look-Up Table，LUT)中。 在本發明之一實施例中，上述之最大亮度LWmax在 CIELAB空間中，滿足下列條件： ^threshold <LW^<LR^ '^eshoM <1^ <^-/threshold<2^®max 其中’ threshold為2 ’ 為顯不益在顯不紅色純色時， 紅色次晝素能夠顯示的最大亮度，為顯示器在顯示綠 色純色時，綠色次晝素能夠顯示的最大亮度，為顯示 器在顯示藍色純色時，藍色次畫素能夠顯示的最大亮度。 在本發明之一實施例中，上述之最大亮度LWmax滿足 下列條件：[Technical Field] The present invention relates to a display driving method, and more particularly to converting red-green-blue image data (RGB image data) A method of driving a display of red-green-blue-image data. ❿ 【Prior Art】 Liquid crystal displays (LCDs) with superior properties, excellent space utilization efficiency, low power consumption, and no emission characteristics have gradually become the mainstream of displays. In order to meet the needs of users, all low-cost businesses are committed to the development of high-color reproduction technology, while the development of high-color reproduction technology and the color saturation of backlights and color filters of liquid crystal displays (color Saturation) is closely related. In order to enable the display to have better brightness performance, displays with red, green, blue and white seed pixels have been proposed. This type of display has better brightness performance, but the color saturation is often due to white color. It has been reduced. In detail, when the display is displaying a solid color (such as red, green, blue), if the white sub-salmon is turned on, the saturation of the solid color will be significantly reduced; otherwise, if the white sub-salmon is not turned on It is also easy for V-shirts to be like a discontinuous visual experience. Therefore, the brightness control of white sub-books has become one of the important considerations for this type of display when driving. In other words, how to find a balance between the color saturation of the solid color and the continuity of the image is one of the problems to be solved in this type of display. 5 201015528 j / 29311 twf.doc/n At present, Kodak and Canon have mentioned how to calculate from the red-green-blue image data (r_G_B image data) in US Pat. No. 6,885,380 and US Pat. No. 5,929,842, respectively. White display data (W display data). However, the purpose of the above patents is to eliminate the jagged edges of the display image, which does not consider whether the color saturation of the display will decrease. SUMMARY OF THE INVENTION The present invention provides a method of driving a display that is adapted to convert red-green-blue image data into red-green_blue-white image data. The invention provides a driving method for a display, which is suitable for driving a red sub-tendin, a green sub-pixel, a blue sub-tendin and a white sub-prime when inputting a red_green_blue image data to the display When the display is smart enough to display - the maximum color gamut, and the display driving method is selected in a maximum color gamut that is displayed by the month b of the display, a target color gamut is selected. Next, the red_image data is converted into a red-green-blue-white image data so that the display can display the target color gamut. After that, the red-green-blue-white image data is input to the display to drive the display. In an embodiment of the invention, the target color gamut is less than the maximum color gamut. In an embodiment of the present invention, the method for converting red_green_blue image data into green blue-white image data includes: when the red, green, and blue image data only includes a single solid color data, according to red_green_blue Image data and target, calculate a maximum brightness of white sub-halogen, and make white-human display a preset brightness [Wdefault, where preset brightness default 7 29311twf.doc/n is less than maximum brightness LWmax; and popular - When the green-blue image data includes a plurality of solid color data, a corresponding brightness of the white sub-halogen is calculated according to the target color gamut and different red_green_blue image data, and the corresponding color is displayed for the white sub-tendin. In an embodiment of the present invention, the preset brightness LWdefault and the corresponding brightness displayed by the white sub-quality are recorded in a Look-Up Table (LUT). In an embodiment of the invention, the maximum brightness LWmax described above is in the CIELAB space, and the following conditions are met: ^threshold <LW^<LR^ '^eshoM <1^ <^-/threshold<2^® Max where 'threshold is 2' is not helpful. When the red solid color is not displayed, the maximum brightness that the red secondary pigment can display is the maximum brightness that the green secondary element can display when the display shows green solid color. The maximum brightness that blue subpixels can display when blue is solid. In an embodiment of the invention, the maximum brightness LWmax described above satisfies the following conditions:
^threshold < Z ' ^eSh〇,d <LWmwi threshold 『max 201015528, 2931 ltwf.doc/n 其中，為第0階的亮度，zj?max為顯示 紅色純色時，紅色次晝素能夠顯示的最大亮度1不 示器在顯示綠色純色時，綠色次晝素能夠顯示的最二: 度，^Anax為顯示器在顯示藍色純色時，藍色次晝素忠 不的最大免度。 〃 本發明之顯示器的驅動方法可在不大幅度地犧牲色 飽和度(color saturati〇n)的情況下，有效提昇影像亮度 ©(brightness) ’並改善顯示影像不連續的情況。 儿又 為讓本發明之上述和其他目的、特徵和優點能更明顯 易懂，下文特舉較佳實施例，並配合所附圖式，作詳細說 明如下。 【實施方式】 圖1為本發明一實施例之顯示器之驅動方法的流程示 意圖。請參照圖1，本實施例之顯示器的驅動方法適於驅 動一具有紅色次晝素、綠色次晝素、藍色次晝素以及白色 & 次晝素之顯示器’當輸入一紅_綠_藍影像資料至顯示器 時，顯示器能夠顯示一最大色域。此時，顯示器所能夠顯 示的最大色域便獲得確定（S100)。在確定顯示器所能顯 不的最大色域（S100)之後，接著於顯示器所能夠顯示的 最大色域内’選定一目標色域（8110)。之後，將紅_綠_ 藍影像貧料轉換為一紅-綠-藍-白影像資料，以使顯示器能 夠顯不目標色域（S12〇)。最後，再將紅_綠_藍_白影像資 料輸入至顯示器，以驅動顯示器（sl3〇)。 在步驟si〇〇、步驟S110與步驟sl2〇中，顯示器所 8 2931 ltw£doc/n 201015528 / 能夠顯示的最大色域以及目標色域主要是由所採用之彩色 濾光膜以及背光源來決定。在本實施例中，為了讓顯^器 所顯不的影像具有高色飽和度，且不易於被使用者觀察= 影像不連續的情況發生，可以採用色飽和度較高的彩色濾 光膜，以使顯示器在被紅_綠_藍影像資料驅動時能^顯= 最大色域（例如為NTSC 108%)，並使顯示器在被紅 藍·白影像資料驅動時，能夠顯示目標色域（例如NTSc ❹ 90%、NTSC 72%或NTSC 50%)。換言之，若採用色飽和 度較高的彩色濾光膜（例如為NTSC 108%)，即使顯示器 中的紅色次晝素、綠色次晝素或藍色次晝素在進行影像^ 面的顯示時，白色次晝素的開啟雖會使顯示器的目標色& 小於最大色域’但顯示器的目標色域仍然能夠維持在不錯 的水準（例如 NTSC 90%、NTSC 72%或 NTSC 50%)，同 樣能夠滿足產品規格的。 值得注意的是，在本實施例中，無論紅-綠_藍影像資 料是否僅包括單一純色的資料（例如：紅-綠-藍影像資料 g 僅包含紅色影像資料、綠色影像資料或藍色影像資料）， 本實施例皆會將白色次晝素開啟，並依據所顯示的影像資 料來控制白色次晝素的穿透率（即白色次晝素所顯示的亮 度），以使顯示器所顯示出的影像不會有色飽和度偏低或 不連續之情況發生。 白色次晝素所顯示的亮度必須與其他次晝素所顯示 的亮度匹配，白色次晝素所顯示的亮度過高或過低都有其 缺點在。詳言之，白色次畫素所顯示的亮度越高，則顯示 器的目標色域便越低’但顯示器較不易被使用者觀察到影 201015528 ---------/ 2931 ltwf.doc/n 像不連續的現象；反之’白色次晝素所顯示的亮度越低’ 則顯示器的目標色域便越高，但顯示器較容易被使用者觀 察到影像不連續的現象。很明顯地，在決定白色次畫素所 顯示的亮度時，必須將其他次畫素所顯7^的免度納入考 量，本發明於下述實施例中提出一種將紅•綠-藍影像資料 轉換為紅-綠-藍-白影像資料的方法，然此方法僅是用以舉 例說明，其並非用以限定本發明。 圖2為本發明另一實施例之顯示器之驅動方法的流程 示意圖。請參煦圖2，在本實施例中，將紅-綠-藍影像資料 轉換為紅-綠-藍-白影像資料的方法至少包括下列兩種情 況。當紅-綠-藍影像資料僅包括單一純色的資料時（例如： 紅-綠藍影像資料僅包含紅色影像資料、綠色影像資料或 藍色影像資料），可根據紅•綠-藍影像資料以及目標色域， 計算出白色次畫素的一最大亮度LWmax，並令白色次晝素 顯示一預設亮度LWdefauit ’其中預設亮度LWdefault小於最 大亮度LWmax (S122)。當紅-綠-藍影像資料包括多種純 色的資料時（例如：紅-綠-藍影像資料不僅包含紅色影像 資料、綠色影像資料或藍色影像資料），根據目標色域以 及不同的紅-綠-藍影像資料，計算出白色次晝素的一對應 亮度’並令白色次畫素顯示對應亮度（S124)。值得一提 的是’白色次晝素所顯示的各個對應亮度皆小於預設亮度 LWdefault。此外’上述之預設亮度LWdefault以及白色次晝素 所顯示的各個對應亮度都記錄於一對照表(L〇〇k-Up Table， LUT)中。 在本發明之一較佳實施例中，上述之最大亮度LWmax 在CIELAB空間中’滿足下列條件： 201015528 2931 ltwf.doc/n illireshold < Z ^max < Z及max A™<Wax<·^ [threshold〈 Z^inax < 2I"Sroax 其中，ZthreshoM為2 ’ ZJ?max為顯不|§在顯示紅色純色時， 紅色次晝素能夠顯示的最大亮度，ZGmax為顯示器在顯示綠 色純色’綠色次晝素能夠顯不的最大亮度，為顯示 器在顯示藍色純色時’藍色次晝素能夠顯示的最^亮度。 ❷ 在本發明之另一較佳實施例中，上述之最大亮度 LWmax滿足下列條件： ^threshold < [ ^max < [^max ^threshold <LW脆 <2LB· 其中，kshonj為第〇階的亮度，為顯示器在顯示 紅色純色時，紅色次晝素能夠顯示的最大亮度，為顯 ® 示器在顯示綠色純色時’綠色次晝素能夠顯示的^大亮 度，為顯示器在顯示藍色純色時，藍色次晝素能夠顯 示的最大亮度。 ‘ 由於本發明將顯示器所欲顯示的目標色域當作決定 白色次晝素之亮度的因素之- ’因此本發明之驅動方法可 以在顧及色飽和度的前提下，充分地改善影像不連續的現 象。 、 雖然本發明已以較佳實施例揭露如上，然其並非用 限定本發明，任何熟習此技藝者，在不脫離本發明之精神 201015528/ 29311twf.doc/n 和範圍内，當可作些許之更動與潤飾，因此本發明之保護 範圍當視後附之申請專利範圍所界定者為準。 【圖式簡單說明】 圖1為本發明一實施例之顯示器之驅動方法的流程示 意圖。 圖2為本發明另一實施例之顯示器之驅動方法的流程 示意圖。 【主要元件符號說明】 S100 :確定顯示器能夠顯示的最大色域 S110:顯示器所能夠顯示的最大色域内，選定一目標 色域 S120 :將紅-綠-藍影像資料轉換為一紅_綠_藍-白影像 資料’以使顯示器能夠顯示目標色域 S130 :將紅-綠-藍-白影像資料輸入至顯示器，以驅動 顯示器 S122:當紅-綠-藍影像資料僅包括單一純色的資料 時，根據紅-綠-藍影像資料以及目標色域，計算出白色次 晝素的一最大亮度LWmax，並令白色次晝素顯示一預設亮 度 LWdefauit ’ 其中預設亮度LWdefault小於最大亮度l Wmax S124 :當紅-綠-藍影像資料包括多種純色的資料時， 根據目標色域以及不同的紅-綠·藍影像資料，計算出白色 次晝素的一對應亮度’並令白色次晝素顯示對應亮度 12^threshold < Z ' ^eSh〇,d <LWmwi threshold 『max 201015528, 2931 ltwf.doc/n where is the brightness of the 0th order, zj?max is the red color when the red color is displayed The maximum brightness 1 is not displayed when the green solid color is displayed, the green sub-tennin can display the second: degree, ^Anax is the maximum exemption of the blue sub-sinus when the display shows the blue solid color.驱动 The driving method of the display of the present invention can effectively increase the image brightness © (brightness) and improve the display image discontinuity without sacrificing color saturation. The above and other objects, features, and advantages of the present invention will become more apparent from the description of the appended claims. [Embodiment] FIG. 1 is a flow chart showing a driving method of a display according to an embodiment of the present invention. Referring to FIG. 1, the driving method of the display of the present embodiment is adapted to drive a display having red scorpion, green scorpion, blue scorpion, and white & sin. When inputting a red _ green _ When the blue image data is displayed to the display, the display can display a maximum color gamut. At this time, the maximum color gamut that the display can display is determined (S100). After determining the maximum color gamut that the display can display (S100), a target color gamut is then selected (8110) within the maximum color gamut that the display can display. Thereafter, the red_green_blue image poor material is converted into a red-green-blue-white image data so that the display can display the target color gamut (S12〇). Finally, the red_green_blue_white image data is input to the display to drive the display (sl3〇). In step si, step S110 and step sl2, the maximum color gamut and the target color gamut that can be displayed are mainly determined by the color filter film and the backlight used. . In this embodiment, in order to make the image displayed by the display device have high color saturation and is not easily observed by the user = the image is discontinuous, a color filter film having a higher color saturation may be used. In order to enable the display to be driven by the red_green_blue image data, the maximum color gamut (for example, NTSC 108%) can be displayed, and the display can display the target color gamut when driven by the red, blue and white image data (for example) NTSc ❹ 90%, NTSC 72% or NTSC 50%). In other words, if a color filter with a high color saturation (for example, NTSC 108%) is used, even if the red scorpion, green scorpion or blue scorpion in the display is displayed on the image surface, The opening of the white secondary can make the target color & display smaller than the maximum color gamut 'but the target color gamut of the display can still maintain a good level (such as NTSC 90%, NTSC 72% or NTSC 50%). Meet the product specifications. It should be noted that, in this embodiment, whether the red-green-blue image data includes only a single solid color data (for example, the red-green-blue image data g only includes red image data, green image data, or blue image. Data), in this embodiment, the white sputum is turned on, and the transmittance of the white quinone (ie, the brightness displayed by the white primal) is controlled according to the displayed image data, so that the display shows The image will not have a low or discontinuous color saturation. The brightness displayed by the white sputum must match the brightness displayed by other sub-halogens, and the brightness displayed by the white quinone is too high or too low. In detail, the higher the brightness displayed by the white sub-pixel, the lower the target color gamut of the display is. 'But the display is less likely to be observed by the user. 201015528 ---------/ 2931 ltwf.doc /n is like a discontinuous phenomenon; on the contrary, the lower the brightness of the white sub-quality is, the higher the target color gamut of the display is, but the display is more likely to be observed by the user. Obviously, in determining the brightness displayed by the white sub-pixel, the exemption of other sub-pixels must be taken into account. The present invention proposes a red-green-blue image data in the following embodiments. The method of converting to red-green-blue-white image data is only for exemplification, and is not intended to limit the present invention. 2 is a flow chart showing a driving method of a display according to another embodiment of the present invention. Referring to Fig. 2, in the embodiment, the method for converting red-green-blue image data into red-green-blue-white image data includes at least the following two cases. When the red-green-blue image data only includes a single solid color data (for example: red-green-blue image data only contains red image data, green image data or blue image data), according to the red, green-blue image data and target In the color gamut, a maximum brightness LWmax of the white sub-pixel is calculated, and the white sub-tenma is displayed with a preset brightness LWdefauit 'where the preset brightness LWdefault is smaller than the maximum brightness LWmax (S122). When the red-green-blue image data includes multiple solid colors (for example, the red-green-blue image data includes not only red image data, green image data, or blue image data), but also according to the target color gamut and different red-green colors. For the blue image data, a corresponding brightness of the white sub-tendin is calculated and the white sub-pixel is displayed for the corresponding brightness (S124). It is worth mentioning that each of the corresponding brightnesses displayed by the white color is less than the preset brightness LWdefault. In addition, the above-mentioned preset brightness LWdefault and each corresponding brightness displayed by the white sub-quality are recorded in a look-up table (L〇〇k-Up Table, LUT). In a preferred embodiment of the present invention, the maximum brightness LWmax described above 'satisfies the following conditions in the CIELAB space: 201015528 2931 ltwf.doc/n illireshold < Z ^max < Z and max ATM<Wax<· ^ [threshold< Z^inax <2I"Sroax where ZthreshoM is 2' ZJ?max is not visible|§When red solid color is displayed, the maximum brightness of red secondary pigment can be displayed, ZGmax is the monitor displaying green solid color' The maximum brightness that green scorpion can display is the best brightness that blue color can display when the display shows blue solid color. In another preferred embodiment of the present invention, the maximum brightness LWmax described above satisfies the following condition: ^threshold < [ ^max < [^max ^threshold < LW crisp < 2LB· where kshonj is the third The brightness of the order is the maximum brightness that the red bismuth can display when the display shows red solid color. It is the brightness of the green sputum that can be displayed when the green color is displayed. The display is in blue. The maximum brightness that blue secondary pigments can display when in solid colors. Since the present invention regards the target color gamut to be displayed by the display as a factor determining the brightness of the white sub-halogen - the driving method of the present invention can sufficiently improve the image discontinuity while taking into account the color saturation. phenomenon. Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the present invention, and those skilled in the art can make some modifications without departing from the spirit and scope of the present invention 201015528/ 29311 twf.doc/n. The scope of protection of the present invention is defined by the scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic flow chart showing a driving method of a display according to an embodiment of the present invention. 2 is a flow chart showing a driving method of a display according to another embodiment of the present invention. [Main component symbol description] S100: Determine the maximum color gamut S110 that the display can display: within the maximum color gamut that the display can display, select a target color gamut S120: convert the red-green-blue image data into a red_green_blue - white image data 'to enable the display to display the target color gamut S130: input red-green-blue-white image data to the display to drive the display S122: when the red-green-blue image data includes only a single solid color data, according to The red-green-blue image data and the target color gamut calculate a maximum brightness LWmax of the white sub-tendin, and cause the white sub-tendin to display a preset brightness LWdefauit ' wherein the preset brightness LWdefault is less than the maximum brightness l Wmax S124: popular - When the green-blue image data includes a plurality of solid color data, a corresponding brightness of the white sub-halogen is calculated according to the target color gamut and different red-green/blue image data, and the corresponding brightness is displayed for the white sub-tendin.