JPH03140902A - Production of color filter array - Google Patents

Abstract

PURPOSE:To easily obtain the color filter array having a high grade, excellent mass productivity and large area by making the light equiv. to three primary colors RGB of light incident from a transparent photoresist film surface side via optical fibers and exposing the photoresist, then removing a reflecting film. CONSTITUTION:An ordinary glass substrate 2 is used as a transparent substrate and the reflecting film 1 is formed thereon. The transparent photoresist film 3 is formed on the rear surface. Light rays corresponding to red (R), green (G) and blue (B) are made incident via the optical fibers 5 to the respective apertures of a mask 4 patterned for color filters to expose the resist film. Finally, the metallic film 1 consisting of aluminum is removed by using an acid, by which the color filter array is obtd. This color filter arrays has the excellent grade free from the drop-out of picture elements by clogging, etc., can display the good and bright color images, facilitates the formation to the larger area and has the excellent mass productivity. The excellent characteristics are obtd. in this way.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a method of manufacturing a color filter array.

For more details, see LCD (Liquid Crystal Display), ECD
(Electro Chromic Display), ELD (
electroluminescent display), CRT
Color filters used in image display devices such as (cathode ray tube) displays, fluorescent display tubes, and LEDs (light emitting diode displays), and image input devices such as image pickup tubes and solid-state image sensors (CCDs: charge-coupled devices). The present invention relates to a method of manufacturing an array.

(Prior art) Color image display is achieved by layering filters of the three primary colors of light, namely red (R), green (G), and blue (B), on each pixel of an image display element capable of black and white display. . In addition, in an image input device in which elements capable of sensing the intensity of light are arranged in a matrix, each element of the matrix is colored red (R).
Color image input is realized by overlapping , green (G), and blue (B) filters. These fine filters of the three primary colors of light, namely red (R), green (G), and blue (B), are arranged in a mosaic or striped pattern so as to correspond to each pixel, and this is called a color filter array. It is widely used in various color image display devices and color image input devices.

Conventionally, color filter arrays have been produced by printing methods, dyeing methods, electrophoretic coloring methods, and the like. The printing method uses ink (three primary colors of light, red (R)) with pigments dispersed on the base material.
, green (G), and blue (B)) directly using, for example, offset printing.

The dyeing method uses photolithography to process photosensitive acrylic resin or gelatin coated onto a substrate into a predetermined shape, dyes and fixes it using dye, and dyes it in each color (i.e., the three primary colors of light, red (R ), green (G), and blue (B)).

In the electrophoretic coloring method, a transparent electrode patterned in advance by photolithography into a predetermined shape is provided on a base material, and red (R), red (R),
This is a method of coloring green (G) and blue (B).

(Problems to be Solved by the Invention) As described above, the color filter array is a fine color filter, and even if a defect occurs in even one of the pixels, the quality of the product will be significantly impaired. Conventional printing methods have problems with microfabrication, making it difficult to obtain high-quality color filter arrays at a high yield. Although it is possible to produce high-quality color filter arrays using the staining method and electrophoretic coloring method, they are inferior in mass production due to the use of photorin graphs, and have the disadvantage that large-area products cannot be easily obtained. . In view of this situation, the present inventor has conducted extensive research and has arrived at the following invention.

(Means for Solving the Problems) The present inventor aims to solve the problems in the conventional method of manufacturing a color filter array. . That is, in the present invention, a reflective film is formed on one side of a transparent substrate, and a transparent photomethyst film is formed on a surface of the substrate different from the surface on which the reflective film is formed, and is arranged at a position corresponding to the RGB pattern of a color filter array. This method of manufacturing a color filter array is characterized in that RGB-equivalent light is incident from the surface side of a transparent photoresist film through an RGB-compatible optical fiber, and after exposure, the reflective film is removed.

The transparent photoresist in the present invention is not particularly limited, but epoxy-based, acrylate-based, polybutadiene, etc. can be used.

In the present invention, the RGB-equivalent light incident on the opening of the mask of the pattern of the color filter array is not particularly strictly defined, but the wavelength of each R is 3.
00-350 nanometers, G is preferably 250-300 nanometers, and B is preferably 200-250 nanometers. Also,
The incident laser beam is a linearly polarized laser, and the electric field vector is set in a direction perpendicular to the incident plane during exposure.

The method for removing the reflective film is not particularly limited, but it is preferable to use chemicals such as acids. Furthermore, in the present invention,
A protective layer may be provided on top of the color filter array,
Alternatively, the substrate may be removed. Further, it is preferable to dye, color, or apply a masking process such as providing a reflective film to a portion other than a portion of the filter.

According to the present invention, since a multilayer interference filter is formed by utilizing the change in refractive index caused by the curing of a transparent photoresist, it is possible to control the shape of a color filter pattern. Filter pattern edges can be sharpened. Furthermore, by controlling the number of layers and refractive index of the multilayer film formed by exposure within the transparent photoresist, it is possible to easily obtain any desired transmission wavelength half-width and transmittance.

The laser beam incident on the transparent photoresist is reflected by the reflective film, and the two beams generate a standing wave.

Antinodes of the standing wave exist at every half wavelength of the incident light wavelength, and harden the photoresist. However, no energy is imparted to the photoresist at the nodes of the standing waves. Therefore, two types of shoes with different refractive indexes are distributed in the thickness direction, and the optical thickness distribution can be arbitrarily controlled by the wavelength, light amount, and irradiation time of the incident light.

On the surface of the transparent photoresist or on the bonding surface between the transparent substrate and the transparent photoresist, the transparent photoresist has fine irregularities due to its nature, and light is easily scattered. Due to this effect, when the color filter array according to the present invention is used in a display element having poor visibility from an oblique direction, such as an LCD (liquid crystal display), the visibility can be greatly improved.

As is clear from its configuration, the color filter array according to the present invention is suitable for large area and mass production, and because it uses optical interference, it has a high degree of freedom in the half-width of transmitted light and transmittance, making it easy to create vivid colors. It has excellent properties such as being able to use a transparent photoresist with excellent environmental resistance.

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these in any way.

(Example) Examples will be described below based on the drawings.

In FIG. 1, an ordinary glass substrate is used as the transparent substrate, and a reflective film is formed on it (^).

In this example, aluminum was sputtered to a thickness of 5000 angstroms.

Form a transparent photoresist film on the back side of the reflective film (tray).

In this example, the photoresist was spin-coded to a thickness of 5 microns.

Next, the three primary colors of light, red (R) and green (
G), the light from the mask is made to enter the transparent photoresist using the device mechanism 1) that allows light with a wavelength corresponding to blue (B) to enter through the optical fiber, and exposure is performed (
Takeshi).

In this example, a single mode optical fiber and a white laser were used as the optical fiber and the light source, respectively.

Finally, the aluminum metal film is removed using acid.

In this example, nitric acid was used.

Through the above process, a dot pattern of red (R), green (G), and blue (B) with a width of 70 μm and a length of 70 μm, a half-value width of 100 nanometers, and a transmittance of 95% is formed by 2001 horizontal by 200 vertical dots. An m-color filter array was obtained.

When the obtained color filter was used in a liquid crystal display element, a good color image was obtained.

(Effects of the Invention) As described above, the color filter array of the present invention has excellent quality without missing pixels due to clogging, etc., and enables good and clear color image display.
It also has excellent properties, such as being easy to expand into a large area and being suitable for mass production.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of the manufacturing process of a color filter array shown in Examples. Early II! 1 (a) (b)

Claims (1)

[Claims] (1) forming a reflective film on one side of a transparent substrate, and forming a transparent photoresist film on a different side of the substrate from the side on which the reflective film is formed;
RG through optical fibers corresponding to RGB arranged at positions corresponding to the pattern of the color filter array.
Light equivalent to B is incident from the transparent photoresist film side,
A method for manufacturing a color filter array, comprising removing a reflective film after exposure.