JP2005084168A - Display screen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide method for constituting a display screen which attains multi-colored display having a wide color reproduction region and sufficient contrast by using dots of four-color alternative display. <P>SOLUTION: The display screen consists of a combination of three kinds of the four-color alternative display dots. The four-color alternative display dots are the four-color alternative display dots displaying a first chromatic color which is one color selected from the first set of the chromatic colors of the arbitrary three colors, a second chromatic color which is another one color of the first set of the chromatic colors of the arbitrary three colors, a third chromatic color which is one color selected from the set of the second three colors consisting of the complementary colors for the respective colors belonging to the first set of the chromatic colors of the arbitrary three colors, and the achromatic color having specific lightness. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a reflective digital display screen. More specifically, it is a collection of dots that can display four colors as an alternative, such as an element in which electrophoresis, magnetophoresis, electrochromic, etc. are multilayered or compounded, a multi-color coating rotary body display element, etc. The present invention relates to a screen that expresses colors.

  As digital display devices capable of multicolor display, there are many self-luminous devices represented by cathode ray tube displays, plasma displays, electroluminescence, and the like. In addition, liquid crystal displays do not emit light by themselves, but when used as a reflective display device, they use a polarizing filter or color filter, so that in principle, only a part of the incident light can be reflected, resulting in a dark and low contrast ratio. In general, a backlight or a front light is used for the purpose of compensating for an insufficient amount of light to display a simple character or image.

  These digital display devices require energy to emit light, and also require energy to continue displaying the display content at a certain point in time. However, due to the rapid spread of portable information terminals such as mobile phones, PDAs, and notebook personal computers in recent years, there is a strong demand for thin display devices that consume less energy and extend battery driving time.

  Examples of color devices that satisfy this demand include vertical electrophoretic display devices with color filters, multilayered horizontal electrophoretic display devices (see Patent Documents 1 and 2), and multi-color separately-rotated display devices (Patent Documents 3 and 3). 6) A composite control system display device (see Patent Documents 7 to 9) has been proposed.

  These are a kind of reflective display devices that do not self-emit, and dots composed of two-color to eight-color alternative display elements are arranged independently without overlapping. More specifically, in the case of a device composed of dots that can display any one of five or more colors, each dot can display at least one of the three primary colors, the white expression, and the black expression. The pixel can be composed of a single dot or a pixel can be composed of a plurality of dots. For example, a multi-layer horizontal electrophoretic display device (see Patent Document 2) or a multi-color separately-separated rotating body display device ( Patent Documents 5 to 6).

  In addition, when a device is composed of dots that can display any one of the four colors, and each dot is displayed as one of the three primary colors and the white expression, the black expression has three dots. Each of the three primary colors, such as CMY or RGB, can be expressed for the first time. For example, there is a multi-color divided rotary body display device (see Patent Documents 3 to 4). In addition, a device composed of dots that can selectively display one of two colors or three colors is not within the scope of the present invention, but includes a vertical electrophoretic display device with a color filter, a multi-layer horizontal An electrophoretic display device (refer to Patent Document 1), a composite control system display device (refer to Patent Documents 8 to 9), and the like are included, and color display is not possible unless it is always composed of three or more dots.

  For the device color expression method that can be selected from among three or more colors, select from three colors of cyan / green / white, magenta / blue / white, and yellow / red / white. By pixels composed of three types of dots that have the ability to display (Patent Document 1) From three colors of red / black / white, three colors of green / black / white, and three colors of blue / black / white By a pixel composed of three types of dots having the ability to display by alternative (Patent Document 9) Each dot has an alternative display ability from the three primary colors of red / green / blue (Patent Document 8), each A dot that can be displayed alternatively from four colors including white (Patent Document 4) A dot that can display any one of four colors of cyan / magenta / yellow and white (Patent Document 3) plus black 5 colors One that can be displayed alternatively (Patent Document 2) Further one that can be displayed alternatively from six colors including green (Patent Document 5) Further one that can be displayed alternatively from eight colors including red and blue (Patent Document 6) ) Etc. were proposed.

  In a light-emitting full-color display method such as a cathode ray tube display, three additive mixed colors, that is, red, green, and blue are used. Actually, a full color is expressed by multiplying the above three colors with a substantial black color in which all three additive colors are turned off. On the other hand, as a reflection-type full-color display method that does not self-emit, printing such as offset is generally used. In printing, four colors including three subtractive colors and black, that is, four colors of cyan, magenta, yellow, and black are printed. Used as a basic color combination. Actually, a full color is expressed by multiplying the ground color of the printing medium, which is often white, with the above four colors.

  When trying to express multiple colors using two-color alternative display dots, multiple types of two-color alternative display dots are required. Usually, from the viewpoint of a reflective device, it is possible to use the same color combination as printing. There were many. That is, white corresponding to the ground color of cyan and paper, similarly magenta and white, three types of two-color alternative dots of yellow and white, or four types of two-color alternative display dots including black and white are used. There are many things.

  In this case, a collection of three or four types of dots one by one is the minimum unit of color display, that is, a pixel. Considering display with one pixel, for example, to display magenta, one of three or four types of dots displays magenta, and the other two or three display white. This means that only a whitish magenta display with low saturation can be obtained. The same applies to cyan and yellow. Further, when displaying the darkest color, each dot of one pixel displays cyan, magenta and yellow in the case of 3 dots, and cyan, magenta, yellow and black in the case of 4 dots. However, it becomes brighter and less black than the black ink alone as in printing.

  As can be seen from the above, when using the same color combination as printing when expressing multiple colors using two-color alternative display dots, there is a problem that the black expression becomes bright and the color expression becomes whitish. . That is, only a display screen with a low contrast ratio can be obtained. For humans to obtain information from a display medium, there are two main types: from characters and from images. When humans recognize images, color expression occupies an important position, and when characters are recognized, contrast is important. Occupies a great position.

  However, as described above, a combination of subtractive colors that has been generally used in the past, cyan / white, magenta / white, yellow / white, two types of one-color alternative dots, or four types of two colors including black / white are added. In the display with alternative display dots, only a whitish and pale color could be expressed. For example, this means that only images that are viewed through glasses that are cloudy with steam can be displayed, which makes it difficult for humans to see.

  From the above, in order to display a better image, it is desired that each dot can be displayed in three or more colors. Recently, a lateral electrophoretic layer stacked display device (Patent Document 2) and a multi-color coating rotary display device (Patent Documents 5 to 6) have been proposed as juxtaposed devices that can display one of five or more colors. Has been.

  Of these, in order to perform an alternative display of five or more colors in a horizontal electrophoretic layer laminated display device, four or more horizontal electrophoretic layers must be laminated, and the structure is extremely complex. There is a drawback that the viewing angle becomes narrower as the layers are stacked. For this reason, the horizontal electrophoretic layered display device with 5 colors or more correctly expresses the color of the part that appears directly in front of the display, but discolors the part that is viewed slightly at a distance from the eye, and the correct image is displayed. The problem of invisibility arises.

The multi-color coating rotating body display device has a section obtained by equally dividing the rotating body in the circumferential direction into each specific color, and only one section is installed under a window visible from the surface, and 360 ° is equally divided. It is a device whose rotation is controlled by a magnetic field or an electric field so that it can be stopped at every fixed angle. Therefore, even if the number of selectable colors increases, there is no change in thickness or viewing angle because the layers are not stacked. However, the interval between the dots is always larger than the diameter of the rotating body. However, as the number of colors to be selected increases, the width of the dot is equal to the circumference of the rotator divided by the number of colors, the maximum is the case of two colors, the same width compared to the diameter of the rotator, ie The cross-sectional area cut by the plane including the axis of the rotating body is 100%, 86% for 3 colors, 70% for 4 colors, 50% for 6 colors, and 35% for 8 colors. Actually, since a space is also required between the rotating bodies around the periphery, the aperture ratio is smaller than the above-described percentage, and furthermore, the aperture ratio of the display window decreases as the number of colors increases, and only the matrix increases. From this, it can be seen that even in a multi-color coating rotary body display device, the realistic configuration is up to about one of four colors.
JP 2002-350903 A Japanese Patent Laid-Open No. 2002-333643 JP 05-188882 A Japanese Patent Laid-Open No. 10-214048 JP 2000-148047 A JP 2000-148049 A Japanese Patent Laid-Open No. 9-50052 JP-A-10-161161 JP 2002-277904 A

  In view of the above, there has been a demand for a method for constructing a color display device that uses four color alternative display dots per dot and has a wide and well-balanced color reproduction range and a high contrast expression.

  An object of the present invention is to provide a method for constructing a display screen capable of multi-color display using a color-selective display dot and having a wide and well-balanced color reproduction range and sufficient contrast.

  The present invention is a display screen in which three types of four-color alternative one display dot are combined, and the four-color alternative one-display dot is one color selected from a first set of arbitrary three chromatic colors. A first chromatic color that is, and a second chromatic color that is another one color adjacent to a specific direction of the Munsell ring in the first set of the three chromatic colors, and the three arbitrary colors. 4 color options for displaying a third chromatic color, which is one color selected from the second set of three colors consisting of complementary colors for each color belonging to the first set of chromatic colors, and an achromatic color having a specific brightness The present invention relates to a display screen that is one display dot.

  The present invention also relates to the above display screen in which the first chromatic color is different from each other and the third chromatic color is different from each other among the three types of four-color selective one dot.

  The present invention also relates to the display screen, wherein the first set is the three primary colors.

  The present invention also relates to the above display screen in which the three primary colors are three colors of cyan, magenta and yellow, or three colors of red, green and blue.

  The present invention also relates to the above display screen in which the achromatic color is white or black.

  The present invention is a known combination of colors, such as a display with three cyan / magenta / yellow / white four-color alternative display dots or a display with three red / green / blue / white four-color alternative display dots. The color reproduction range is expanded by adopting three types of four-color alternative display dots of cyan / magenta / red / white, magenta / yellow / green / white, and yellow / cyan / blue / white. Therefore, it is possible to construct a display screen that can perform good multicolor display. Compared to the known color combination, which is a display with three cyan / magenta / yellow / white four-color alternative display dots and a display with three red / green / blue / white four-color alternative display dots, Of the three primary colors such as red / green / cyan / white, green / blue / magenta / white, and blue / red / yellow / white, which are the color combinations of the present invention, the same set of three primary colors 4 colors displaying an achromatic color having an arbitrary one color selected from a set of three colors consisting of another chromatic color adjacent to the Munsell ring in a specific direction and complementary colors of the three primary colors and a specific brightness By adopting 4 color alternative display dots that combine 3 types of alternative display dots, it is possible to achieve a balanced, sufficiently saturated and natural color expression. It has been revealed.

  The four-color alternative display dot used in the present invention is a display dot used for display such as a known electrophoretic, magnetophoretic, electrochromic multi-layered or composited element, a multi-color divided rotary display element, and the like. Can be used.

  The present invention is a display screen in which three types of four-color alternative display dots are combined in order to provide a display screen with a wide color reproduction range, and the four-color alternative display dots have arbitrary three colors. A first chromatic color which is one color selected from the first set of chromatic colors and another one color adjacent to the specific direction of the Munsell ring among the first set of three chromatic colors. A third chromatic color that is one color selected from a second chromatic color and a second three color set consisting of complementary colors for each color belonging to the first set of the three arbitrary chromatic colors; It is a four-color alternative display dot that displays an achromatic color having lightness.

  In the present invention, “specific” means that if an arbitrary direction or lightness is determined by one dot, the same specific direction or specific lightness is determined for the other dots. It does not mean that the correct direction or brightness has been determined.

  In addition, two chromatic colors selected from a first group consisting of arbitrary three chromatic colors and one color selected from a second group of three colors consisting of complementary colors for each color belonging to the first group The range of colors that can be expressed can be significantly improved by using a combination of three types of dots that display chromatic colors and achromatic colors.

  These are distinguished by colors that can be displayed, and the size and shape of the element itself may be different. Further, the color may change within a range that does not impair the effects of the present invention as the size and shape change. Also, the number of elements may vary depending on the type. In addition, the arrangement of display dots may be any arrangement.

The types of display dot combinations preferably used in the present invention are:
Cyan / magenta / red / white, magenta / yellow / green / white, yellow / cyan / blue / white or cyan / magenta / green / white, magenta / yellow / blue / white, yellow / cyan / red / white 3 types of cyan / magenta / blue / white, magenta / yellow / red / white, yellow / cyan / green / white, or cyan / magenta / red / white, magenta / yellow / blue / white, yellow / cyan / Green / White or Cyan / Magenta / Green / White, Magenta / Yellow / Red / White, Yellow / Cyan / Blue / White, Cyan / Magenta / Blue / White, Magenta / Yellow / Three types of Lean / White, Yellow / Cyan / Red / White or Red / Green / Cyan / White, Green / Blue / Magenta / White, Blue / Red / Yellow / White or Red / Green / Magenta / White, 3 types of green / blue / yellow / white, blue / red / cyan / white or red / green / yellow / white, 3 types of green / blue / cyan / white, blue / red / magenta / white or red / green / 3 types of cyan / white, green / blue / yellow / white, blue / red / magenta / white or 3 types of red / green / magenta / white, green / blue / cyan / white, blue / red / yellow / white Red / Green / Yellow / White, Green / Blue / Magenta / White, Blue / Red / Cyan / White or Cyan / Magenta / Red / Black, Magenta / Yellow / Green / Black, Yellow / Cyan / Blue / 3 types of black or 3 types of cyan / magenta / green / black, magenta / yellow / blue / black, yellow / cyan / red / black or cyan / magenta / blue / black, magenta / yellow / red / black, yellow / 3 types of cyan / green / black or cyan / magenta / red / black, magenta / yellow / blue / black, 3 types of yellow / cyan / green / black or cyan / magenta / green / black, magenta / yellow / Red / green / cyan / black, yellow / cyan / blue / black, magenta / yellow / green / black, magenta / yellow / green / black, yellow / cyan / red / black , Green / Blue / Magenta / Black, Blue / Red / Yellow / Black or Red / Green / Magenta / Black, Green / Blue / Yellow / Black, Blue / Red / Cyan / Black or Red / Green / Yellow / black, green / blue / cyan / black, blue / red / magenta / black or red / green / cyan / black, green / blue / yellow / black, blue / red / magenta / black Or Red / green / magenta / black, green / blue / cyan / black, blue / red / yellow / black or red / green / yellow / black, green / blue / magenta / black, blue / red / cyan / One of three types of black. By using these three types of display dots, a wide color reproduction range and a sufficient contrast ratio can be provided, and the expressive power is improved.

  In order to evaluate the effect of the present invention, a display using three color / single-color display dots of cyan / magenta / yellow / white, which is a combination of colors described in Patent Document 3 as Comparative Example 1, and a patent as Comparative Example 2 A display by three four-color selective display dots of red / green / blue / white, which is a combination of colors described in Reference 4, and cyan / magenta / which is one of the combinations of colors of the present invention as Example 1. The display using three types of four-color selective display dots of red / white, magenta / yellow / green / white, and yellow / cyan / blue / white is another example of the color combination of the present invention as Example 2. 3 colors are available: Red / Green / Cyan / White, Green / Blue / Magenta / White, Blue / Red / Yellow / White It was carried out the display of the experiment by the door.

  In this experiment, a screen display was simulated using a commercially available proofing machine (Konica Graphic Imaging Corporation Digital Consensus Pro) used for offset printing proofing. Since the present invention does not depend on the image display means, the effect of the present invention can be confirmed also in this simulation.

  In order to simulate the screen display with the calibrator, an image corresponding to one dot of the display screen was created with a plurality of pixels of the calibrator. The output resolution of the calibrator used was 2400 dpi, and approximately 42 μm square dots could be reproduced. In Comparative Example 1, four color alternative display dots are arranged in a 3 dot × 1 dot arrangement of three cyan / magenta / yellow / white, and in Comparative Example 2, four color alternative display dots are red / green / blue / A white dot array of 3 dots × 1 dot was used. In the present invention, as Example 1, three types of four-color selective display dots, cyan / magenta / red / white, magenta / yellow / green / white, and yellow / cyan / blue / white are arranged in this order. 3 dots x 1 dot arrangement and 3 types of 4 color selection display dots as Example 2, one each for red / green / cyan / white, green / blue / magenta / white, blue / red / yellow / white Are arranged in a 3 dot × 1 dot arrangement in this order.

  In each experiment, 64 colors that can be constituted by four color alternative dots according to Comparative Examples 1 and 2 and Examples 1 and 2 according to the present invention are displayed, and measured with a colorimeter, The contrast ratio was determined from the brightness of the darkest color. Furthermore, from each example, a hexagon consisting of optimal representations of RGB and CMY was obtained on the a * b * plane of the L * a * b * equal color space, and the color gamuts were compared.

  FIG. 1 shows the measurement results of the color reproducibility of Examples 1-2 and Comparative Examples 1-2 by experiment.

  As shown in FIG. 1, in Comparative Examples 1 and 2, only the three primary colors exhibit high saturation, but the intermediate color is remarkably close to the origin and becomes whitish and cloudy. Accordingly, it can be seen that the expression of the three primary colors solidly painted allows vivid color expression, but is not suitable for displaying natural images displayed in various intermediate colors such as photographs. On the other hand, in the first and second embodiments, the three primary colors are not as far from the origin as the comparative examples, but the intermediate colors are also at a sufficient distance from the origin in the same way, and are suitable for expressing natural images that frequently use intermediate colors. Understand.

  Table 1 shows the contrast measurement results of Examples 1-2 and Comparative Examples 1-2 by experiment.

  The contrasts of cyan / magenta / red / white, magenta / yellow / green / white, yellow / cyan / blue / white, which are color combinations of the present invention, are 7.24, and the color combination of the present invention is red / green / white The contrasts of cyan / white, green / blue / magenta / white, and blue / red / yellow / white were 7.06, and the same contrast ratio as in the comparative example was obtained.

FIG. 1 shows cyan, blue, magenta, and red with the maximum saturation that can be displayed in Examples 1 and 2 and Comparative Examples 1 and 2 on the a * b * coordinate plane representing the hue in the L * a * b * color system. Represents the a * b * coordinates of the six colors of yellow, green, and the origin is an achromatic color, indicating that the further away from the origin, the higher the saturation and the more vivid.

Claims (5)

A display screen that combines three types of four-color alternative display dots,
The four-color-selection-display dot is a first chromatic color that is one color selected from a first set of any three chromatic colors and a first set of the three chromatic colors. Of these, a second chromatic color that is another one color adjacent to the specific direction of the Munsell ring and a second three-color set consisting of complementary colors for each color belonging to the first set of the three arbitrary chromatic colors. A display screen that is a four-color alternative display dot that displays a third chromatic color that is one selected color and an achromatic color having a specific brightness. The display screen according to claim 1, wherein the first chromatic color is different from each other and the third chromatic color is different from each other among the three types of four-color selection one dot. The display screen according to claim 1 or 2, wherein the first set is three primary colors. 4. The display screen according to claim 1, wherein the three primary colors are three colors of cyan, magenta, and yellow, or three colors of red, green, and blue. The display screen according to claim 1, wherein the achromatic color is white or black.

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