TW452752B - A display device - Google Patents

Abstract

A display device comprises a matrix (11) of pixels (10) arranged in rows and columns, each pixel (10) being selectively settable into a light transmissive condition and an opaque condition, and an illumination system, comprising an array of elongate elements (4, 5, 6) which provide light in response to electrical impulses, the elements (4, 5, 6) being arranged side by side to give a striped appearance and to face the matrix (11). Adjacent elements provide light having a different one of a plurality of colours. The matrix (11) is addressed using a row by row addressing sequence. During part of this sequence, a row of pixels (10) is illuminated with light of a first colour from a first element, whilst a remote row of pixels is illuminated with light of a different colour from a further element. This enables more efficient illumination of the matrix (11) than with conventional colour sequential displays in which all rows are illuminated with the same colour at the same time.

Description

4 52 7 b V. Description of the invention (1) Background of the invention The present invention relates to a display device, which includes a pixel array arranged in rows and columns. Each pixel system can be selectively set in a multi-light transmission state; In the light transmission state, a device uses a parallel addressing method to address images: pixels' and a lighting system. In particular, it relates to a display device (that is, a conventional color 1-color sequential display) ′ in which a given pixel is illuminated with different color light rays at different times ’to form an image with a plurality of colors. There are currently known a variety of display devices that utilize color sequential light emission to produce multi-color displays from non-radioactive displays such as liquid crystal displays that are essentially monotonous. One device is described in EP-A-026 1 896 Europe The disadvantage of this particular device in the patent application is that the display can only be illuminated when it is not updated. Since most displays take a significant period of time to update (ie, frame time), the final image is illuminated for only a fraction of the frame time, resulting in a display with low brightness. ^ One of the color-sequential displays that can be illuminated during the update is described in EP-Α-0 478 1 8 6 European Patent Application. Although this display describes problems, the display device is still light-free for an average of 50% of the time. t state, so it is still a display with undesired brightness. 3 Summary of the invention / 、 Provision of patent application scope No. 1 It provides patent application scope No. 12 which is superior to all the display devices listed at the same time according to one of the first content of the present invention and described in item 11. According to the second aspect of the present invention, the lighting system according to items 16 to 16. The present invention makes more effective array lighting η 5 2 7 5 2 5. Description of the invention (2) or the conventional color sequence display illuminated by the same color at the same frame time, which can be illuminated by different colors in a single frame time Spaced ranks. The drawings briefly illustrate an example of the present invention, which will be described by way of examples and with reference to related drawings, in which: FIG. 1 discloses a perspective view of a display device of the present invention; FIG. 2 discloses light that the display device shown in FIG. 1 does not output in continuous time Figure 3 illustrates an example of a conventional addressing sequence; Figure 4a illustrates another example of a conventional addressing sequence; and Figure 4b illustrates an example of a fixed address sequence of the present invention. Detailed description of the invention FIG. 1 discloses a perspective view of a display device according to the present invention. The display device includes a pixel array (11) arranged in rows and columns. Each pixel (1 0) can be selectively set in a multi-light transmission state and a In the low-light transmission state, the device (12) uses a row-by-row addressing method to address pixels, and a lighting system includes a row of (13) long elements (4, 5 5 6) to provide light to the electronic pulses to Array, the elements are arranged side by side to present a long appearance and face the array, while the adjacent elements providing light have a plurality of different colors, and the device (7) is to provide electronic pulses to the elements in a predetermined order, and It is synchronized with this parallel addressing system. In this example, the pixel includes a photoelectric material, such as a layer of magnetoelectric liquid crystal sandwiched between the substantially transparent row and column electrodes, and the electrodes are orthogonal to each other and overlap to define the pixel. The array of lighting systems (13) includes a backlight, and the array of components includes an electroluminescent material, such as a luminescent polymer. Bars or yuan

45275- V. Description of the invention (3) The list provides one of a plurality of different predetermined colors, and in the present invention, the green light C is numbered 4), the red light (5), or the blue light (6). In response to the individual electronic signals from the circuit combination (7), the circuit combination includes a backlight driving device. A conventional serial display is disclosed in International Patent Application No. WO9633483 (Cambridge Display Technology Corporation). Each pixel in the pixel column is sequentially addressed and only one color is displayed at a time (for example, red, green, or blue). The effect is not as good as described in the present invention, the present invention can display more than one color at the same time. • The array of electroluminescent elements forms a generally planar structure, and when used, it is arranged to face a settable pixel array. An arbitrary diffuser (8) is provided in the light path from j 歹 K 1 3) to the array (1 1). 'This diffuser can reduce the display = a long strip appearance when used. For example, the diffuser can include a The display of the frosted glass display is set as follows. There is no lighting system when opening and closing: T lights (that is, no component provides light to the array), data-write is from the array wf column, and from the top column Start 9 This means the electronic data pulse system π:;: "is used for optical identification and then energized υ θ: θ, the element containing the top row of the lighting system is written to the top row array: i-line to array The color of this component is equivalent to the color data already represented by the same row as i =. Subsequent to the top of the array, the color data in the first row is written, and the addressing action is

Page 8 452752 丨 V. Description of the invention (4) i corresponds to the data of the same color and is repeated on the array of the next adjacent column. j When the majority of the columns have been addressed in this way for the first time and the next column to be addressed is closer to the second component of the lighting system with the same color as the first component, then this time a component is outside the first component Do the power-up, and repeat this procedure for the subsequent columns until the entire array has been addressed and illuminated by all the elements of the given color. I later happened that the array in the top row was blank and had a low light transmission state, and the top element in the backlight row was powered off. When implemented, multiple rows of arrays will be blank, while multiple elements with backlight rows with the same color will be powered off before new data corresponding to different color data is written to the top row array. This is to prevent or reduce Light with a certain color element diffuses or leaks into other elements in the row providing a different color. In Figure 1, area 20 is illuminated by the green light of element 4, and area 21 I is not illuminated at this time. 'Area 2 2 is blank and the pixels are in a low light transmission state. [And area 2 3 is red by element 6. illumination. | When the blank area (2 2) is kept as small as the minimum light leakage mentioned above, then | can produce the brightest and most effective display, the size of the blank area needs to be large enough to make the columns have sufficient blankness' And the optoelectronic material has sufficient time to recover before new data is written. 'This available time is expressed, and it is 400 microseconds for the Ho echst AEG 4851 material used in the above example. The actual width of the blank area (2 2) will depend on the precise design of the lighting system, which may be the unlighted part of the backlight column (2 1), or the array blank area where the pixels are in a low light transmission i state to almost no height ( 22). Its important characteristic is that some dark areas between the i-emitting array parts are illuminated by light of different i colors at the same time (ie, areas 20, 23).

Page 9 452752 V. Description of the invention (5): After the top of the display has been blanked as described above, the new data is written into the top row of the display 丨 This new data is equivalent to the data representing a different color, which is closest to the top of the display; And the backlight column elements that provide the appropriate color light are then powered on, and the sequence is implemented as before, until all the columns have been addressed and written with data with this new color i I i 丨 color, and all backlights with the same color Column components are ί

I have power. If only two colors are used, the whole process will start from the starting point again! However, if a third color is to be written, the process will repeat the color analogy, and the order of the foregoing conditions will be in the addressing order During this period, the light i I line is continuously output from the display shown in FIGS. 2 (a) to (f). | I In order to keep the update rate high enough to avoid flicker that should be noted and keep the line time i: as long as possible (to reduce energy consumption and energy loss), the address in the next column should be addressed at any time |! The last line of the display! When finished, the top line is immediately rewritten. This means that before the last column is written, the top line of the | t I display is blank. If there is no limitation on the operating speed of the display, when the data is written in the last column and the display is written in monochrome and in the address order when the display is in monochrome lighting, it starts between the first and the first row representing the next color data in sequence. There should be a period of time.丨 Although in the previous article, the display was started because it was completely blank, but this is not a necessary requirement, because the first color will be written to the entire array quickly. The advance display of the display device is not important; it can also be changed from the array. The bottom row starts to address, 丨 'i I and move up.丨 i The above display devices can provide advantages over previous technology display devices,

I because the length of time that a given portion of the display is dark can be smaller than the frame time I I! 丨, making the display much brighter than conventional displays. : Page 10 4 527 5 2 i. V. Description of the invention (6) The number and width of the backlight elements are configured so that when combined with the diffuser :, the bar appearance of the display can be reduced, and the diffuser's light distribution is maintained. To the minimum. It is important that if the backlight column elements have N predetermined colors, then each element is constructed and configured to illuminate at least N columns of displays, and there are N-1 elements of different colors between the nearest neighboring elements with the same color .

; I I It is necessary but not important that the array system is constructed so that it can have a blank column, and 1

, I | The other is written at the same time, in order to maintain the minimum write rate required for data.

! A magnetoelectric liquid crystal layer is an example of a photoelectric material, which can be operated in this way; Γ operation, or blanking and writing can be performed alternately.丨 The above display device can be advantageously used in different addressing systems, such as the time shown in I 丨 EP ** A-0261901 and EPU319291 patent applications! Weighted gray scale addressing system, which can be incorporated into this case for For reference. (ί Figure 3 reveals a 3-bit binary system used in a 7-column display device:! Addressing sequence example, which can achieve 8 gray levels and detailed in i EP-A- 0 2 6 1 9 0 1 In the patent, each horizontal line in this figure is equivalent to one column in the display device, and each square in the horizontal direction represents the time taken to address a single column. The numbers 1, 2, and 3 in the columns in the central area reveal The binary importance of the data to be written (1 indicates the least significant bit, and 3 indicates i 'indicates the most significant bit). The position of the numbers in the vertical direction indicates which column is being addressed, and The horizontal position of the numbers indicates the time when the addressing took place! Phase I! The dark vertical line indicates when the view frames of each column have ended. In a normal color-sequential display, the dark vertical line between successive view frames represents a certain The time when the one-color backlight (that is, all the columns are illuminated at the same time) is powered on and the previous color is powered off. However, the vertical lines in Figure 3 are displayed at different times for different columns.

Page 11 45275 2 丨 V. Description of the invention (7) 丨 Now, it is related to the monochrome display, in which the adjacent columns are substantially adjacent 丨 not in the order of adjacent columns. : 1 If the color sequential backlight is combined with a time-weighted gray scale system 丨 i: (as shown in EP-A-0 3 1 929 3), then most of the displays will be dark | i will have one The significant time period results in a more ambiguous display. The new data corresponding to a different color will only be written to the array when the previous color gamut of each column has reached the correction time! Weighting cycle. This conventional system is shown in Figure 4 (a) In the figure, the system shown is the same as that in Figure 3 and explained earlier. The difference is that the position of the column has been reconfigured so that the first address of a column can make i

! I j The order of this first address is written from top to bottom (or bottom to top). This is an important feature of the invention, that is, the first address of a column in a given view frame moves through substantially adjacent columns in the order of | I. This feature itself is not one of the basics of the time-weighted gray scale system. Element "i 丨 | As can be seen from Figure 4 (a), almost one-third of the available pixels have not produced a light output, because even if the backlight illuminates the pixel, it still transmits less light. , As shown by the shaded line in Figure 4 (a). When the backlight is to be switched from one color to another |: [I color, the thin black area between the frames is used for indication.丨 The result of combining the display device of the present invention with the above-mentioned time-weighted gray-scale addressing system is disclosed in 圊 4 (b). Very little time is used for pixel light emission, and I is in a low-light transmission state. The calculation results are shown in Table 1 below.

When the display column is blank, it is used in the prior art EP-A- 0 3 1 929 No. 3 patent system I '!; A variety of digits gray scale data and the inventor's frame time percentage | 丨 ratio. ί;

Page 12 4 52 7 5 2 V. Description of the invention (8) Table 1 Number of blank lines (previous technique) Blank line time (present invention)% Time blank (previous technique) ° / 〇 Time blank (present invention) 2 3 2 33.0 25.0 3 1 11 3 34.4 ~ 12.5 4 31 4 34.1 6.3 5 79 5 33.8 3.1 6 191 6 33.5 1.6 As can be seen from the table, the display device of the present invention has A higher percentage of time is therefore significantly superior to previous technology systems, especially when many gray levels are used. : Although the element list in the above example includes an electroluminescent material | [lighting system, such as a light-emitting polymer, but other materials such as luminescent organic or inorganic materials can be converted, and the components are not necessarily electrical Fluorescent light, as long as it can emit light (or reflect or scatter) in response to an electronic pulse, especially the element can]! Contain electro-chromatic materials or a polymer dispersed liquid crystal modulator, and have a suitable light source. !

! I

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Claims (1)

452752 VI. Application for patent scope 1. A display device comprising a pixel array (11) arranged in a row and row shape 'each pixel (10) is selectively set in a multi-light transmission state and a low-light transmission state' device (1 2) uses a parallel addressing method to address pixels, and an illumination system includes-a column (1 3) of long elements (4, 5, 6) to provide light to the array in response to an electronic pulse (〗 丨) The components (4, 5'6) are arranged side by side to present a long appearance and face the array, while the adjacent components providing light have multiple different colors, and the device (7) is provided in a predetermined order Electronic pulses to the element (4, 5, 6), which are synchronized with the parallel addressing system, are characterized in that during one of the predetermined sequences, one or more adjacent columns of pixels (10) are first The color light is irradiated, and one or more other pixels (| 0) separated from the one or more adjacent columns are irradiated with a different color of light from another element separated from the first element. 2. For the display device under the scope of the patent application, the adjacent elements that provide light of different colors do not provide the light to the array (丨 丨) at the same time. 3. For a display device according to item 2 of the patent application, wherein the number of rows illuminated by a component is equal to or greater than the number of existing colors. 4. For a display device according to any of the foregoing claims, the parallel addressing system is such that consecutive adjacent pixel columns (10) provided with a given color of light are first addressed in a continuous addressing cycle. 5. For example, the display device of the scope of patent application, wherein the columns in the array (丨 丨) are addressed multiple times, and illuminated with a predetermined color of light, and the time interval between successive addressing of a predetermined column constitutes-geometry The number of stages has a common ratio of at least two to provide complex brightness. 6. The display device according to any one of the preceding claims, wherein the pixel O: \ 57 \ 57840.PTD Page 14: 6. The scope of patent application (1 0) includes a photoelectric material. 7. The display device according to any one of the preceding claims, wherein the pixel (10) comprises a magnetoelectric liquid crystal material. 8. The display device according to any one of the preceding claims, wherein the element i (4, 5, 6) contains an electroluminescent material. 9. The display device according to claims 1 to 7, wherein the element (4, 5, 6) includes an electrochromic material. 1 0. The display device according to claims 1 to 7, wherein the components: (4, 5, 6) include a polymer dispersion liquid crystal modulator. I | 1 1. The display device according to any one of the preceding claims, wherein a diffuser (8) is provided in a light path from the lighting system to the array (1 1). 1 2 — A lighting system for a display, the system includes a row of long | elements (4, 5, 6) to provide light in response to electronic pulses, the elements (4, 5, 6) are side-by-side The ground configuration presents a strip-like appearance and faces the array, while the neighboring elements that provide light have a plurality of different colors, and the device i (7) is used to provide electronic pulses to the elements (4, 5, 6) in a predetermined order. 1 3 · As for the lighting system of item 12 in the scope of patent application, in which the predetermined order! Is to make the elements that are substantially spaced apart from each other at a given number of times in the sequence 丨 (4,5,6) simultaneously provide different elements Light of color. 14. The lighting system according to item 12 or 13 of the scope of patent application, wherein the element (4, 5, 6) includes an electroluminescent material. I 1 5. The lighting system according to item 12 or 13 of the patent application scope, wherein the element | (4, 5, 6) includes an electrochromic material. ί Page 15 6. Scope of patent application 1 6. The lighting system according to item 12 or 13 of the scope of patent application, wherein the component (4, 5, 6) includes a polymer dispersion liquid crystal modulator. Page 16