JP2009063301A - Apparatus and method for inspecting color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for inspecting a color filter which enable detection of color irregularity with excellent sensitivity and convenience. <P>SOLUTION: In visual inspection of a color filter substrate by visual observation or an image pickup element, a monochromatic LED corresponding to each color layer of the color filter substrate is used as an LED light source 10 for inspection. With the color filter substrate held up before a light box 3 using LEDs of individual colors, the LEDs are lighted, being switched over sequentially, so as to conduct the macroscopic visual inspection. Thereby the color irregularity can be easily specified in a short time. By using a monochromatic light source of the LED, mixture of colors of transmitted or reflected light being visually-recognized is little and a contrast of an irregular part of each color is enhanced. Therefore even such subtle irregularity as is usually overlooked can be detected. By using this color filter substrate having little irregularity, a liquid crystal display device having a higher display quality can be realized. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a color filter inspection apparatus and a color filter inspection method, and more particularly, to a color filter inspection apparatus and an inspection method used for manufacturing a liquid crystal display device.

  In recent years, flat panel displays such as liquid crystal display devices have become widespread due to their features such as thinness, light weight, and low power consumption. Conventionally, personal computer monitors and notebook monitors have been mainly used. However, as demand for TV applications increases, there is an increasing demand for more vivid displays, that is, displays with high color reproducibility. In general, many flat panel displays include a color filter substrate having a color layer pattern corresponding to the number of pixels in order to assist color display and color display. In order to improve the color reproducibility described above, This is realized by adjusting the spectrum of the light source of the flat panel display and the spectrum of the color filter substrate. Particularly in a liquid crystal display device, spectrum adjustment of a CCFL (Cold Cathode Fluorescent Lamp) backlight or LED (Light Emitting Diode) backlight light source of a three-wavelength type cold cathode tube, and a color layer of a color filter substrate forming a liquid crystal panel Spectral adjustment is performed.

  In general, a printing method, a photoresist method, an etching method, or the like is used to manufacture a color filter substrate. However, if high-definition, spectral property controllability and reproducibility are taken into consideration, the photoresist is used. The method is preferred. In the photoresist method, a colored composition in which a pigment is dispersed in a transparent resin together with a photoinitiator and a polymerization monomer in an appropriate solvent is applied onto a transparent substrate, and then the color resist is subjected to pattern exposure and development. In this method, the process of forming one color layer is repeated for each color to produce a color filter substrate. Thereafter, the color filter substrate is inspected to check the film thickness unevenness at the time of application, color unevenness due to aggregation of color resists, pattern defects, and the like to make a pass / fail judgment.

  In the color filter inspection process for the liquid crystal display device, in order to detect macro unevenness, as shown in FIGS. 8 and 9, an appearance inspection is performed using reflected light from a Na lamp or the like, or transmitted light from a cold cathode fluorescent tube. (For example, see Patent Document 1 below). In addition, in order to detect unevenness of a specific color layer, there is a method of inspecting light reflected or transmitted by a color filter substrate through a color filter (for example, see Patent Documents 2 to 5 below). Furthermore, as shown in FIGS. 10 and 11, there is a method in which a color filter 28 is inserted between a light source and a color filter substrate to convert it to monochromatic light, and an appearance inspection is performed using the reflected light or transmitted light (for example, , See Patent Documents 6 to 10 below). For example, a white light source may be used as the light source, and an interference filter may be used for conversion to monochromatic light.

JP-A-8-292127 JP 2004-28833 A JP 2003-98036 A JP 2003-294578 A JP-A-2005-121500 JP 2005-148637 A JP 2000-193814 A JP-A-5-281147 JP-A-8-194112 JP-A-56-129844 JP 2005-338261 A

However, as shown in FIGS. 8 and 9, in the appearance inspection using the light reflected by a conventional Na lamp or the like or the transmitted light of a cold cathode fluorescent tube, if there is unevenness specific to a certain color, Red, Green It is difficult to judge on the spot which color process is caused by Blue. This includes white light sources such as fluorescent lamps that include all wavelength regions corresponding to Red, Green, and Blue as inspection light sources, and low-pressure sodium lamps (sodium D-line (588.995nm, 589.592nm)) even at a single wavelength. Since the inspection is performed using an orange-yellow light source having poor color rendering properties, even if there is unevenness in a specific color, as shown in FIG. 12, the transmitted light or reflected light of other colors inhibits the contrast of the uneven portion. The reason is that the detection sensitivity falls due to falling. Therefore, it is necessary to make a comparison using a defect limit sample in which specific color unevenness has already been confirmed. However, for unknown color unevenness shapes, detailed analysis such as color film thickness measurement by destructive inspection of the color filter substrate, or liquid crystal panel as shown in Patent Document 11 is driven and displayed to perform each color inspection. Finally, it is possible to identify the color process causing the unevenness. Further, in color filter inspection, even if a monochromatic light source corresponding to each color layer is simply adjusted using a color filter or interference filter, inspection with high contrast cannot be performed. For example, there is a region where the transmission spectrum of each color overlaps, as in the part of the full width at half maximum FWHM (bg) in FIG. 7, and the light in that wavelength region is transmitted from the subpixels (dots) of both overlapping color layers. Light leaks out. Since the color filter itself does not have a function of adjusting the transmittance for each sub-pixel, it is not possible to perform an adjustment that transmits the transmitted light in the overlapping wavelength region only to the sub-pixel to be inspected. In Patent Document 11, the liquid crystal panel is driven to adjust the transmittance for each sub-pixel (dot), and other than the sub-pixels to be inspected are put in a light-shielding state. Inspection is performed by limiting leaked transmitted light to only the sub-pixels to be inspected. However, in this apparatus, when the inspection target is replaced with a color filter substrate from the panel, the overlapping wavelength region becomes a hindrance factor as described above, and sufficient inspection cannot be performed. Further, although light leakage in a mixed color region due to other colors is eliminated, a panel driving device is required, which complicates the device configuration and increases the cost. Furthermore, if the color filter is not put into the panel process and the panel is not completed, defects such as unevenness as the color filter cannot be recognized, and materials in the meantime are wasted.

  Also, in order to improve color reproducibility with the color filter substrate, it is necessary to increase the purity of the color, increase the pigment concentration of the color layer, increase the thickness of the color layer, or change to a pigment with high colorability To respond. Since the pigment types that can be used in the color filter are limited, the pigment concentration and the film thickness are mainly changed, and when the color reproduction range of the color filter substrate is expanded, the transmittance tends to decrease. This color filter substrate with a wide color gamut causes a decrease in color unevenness detection sensitivity due to color mixing and a decrease in transmittance in the inspection process, so that a liquid crystal display device with high color reproducibility and display uniformity can be obtained with high yield. It was difficult.

  Further, as shown in FIGS. 10 and 11, in the method of obtaining the inspection light sources corresponding to R, G, and B using the color filter 28, the transmittance as the inspection light source is reduced, and the color filter 28 Switching time, maintenance, and workability are inferior to the case of using R, G, and B monochromatic LED light sources. Further, since the switching of the color filter 28 requires some mechanical mechanism and a device for controlling this mechanism (for example, the color filter switching device 29 in the figure), the time is longer than the electrical switching of the LEDs. It takes. In addition, a cold cathode tube mainly used as a white light source has a shorter lifetime than an LED, and therefore it is necessary to stop the inspection process at the time of replacement or maintenance.

  The present invention has been made in view of the above problems, and a main object of the present invention is to provide a color filter inspection apparatus and a color filter inspection method capable of easily detecting color unevenness with high sensitivity. .

  In order to achieve the above object, the present invention provides a color filter comprising at least an LED light source unit that illuminates a color filter substrate on which a plurality of color layers are formed with LEDs, and an LED light source control unit that controls the LED light source unit. In the inspection apparatus, the LED light source unit is configured by arranging LEDs having the number of colors corresponding to the color of the color layer of the color filter substrate in a matrix, and the LED light source control unit converts the LEDs of each color. By sequentially lighting, the color filter substrate is sequentially illuminated with monochromatic light, and color unevenness of the color filter substrate is inspected for each color layer.

  In addition, the present invention is a color filter inspection apparatus including at least an LED light source unit that illuminates a color filter substrate having a plurality of color layers with LEDs, and an LED light source control unit that controls the LED light source unit. The LED light source unit includes a rotatable LED support base having a number of surfaces corresponding to the number of the color layers of the color filter substrate, and LEDs of each color arranged on each surface of the LED support base. By rotating the LED support by the LED light source control unit, the color filter substrate is sequentially illuminated with monochromatic light, and color unevenness of the color filter substrate is inspected for each color layer.

  In addition, the present invention is a color filter inspection apparatus including at least an LED light source unit that illuminates a color filter substrate having a plurality of color layers with LEDs, and an LED light source control unit that controls the LED light source unit. The LED light source unit includes an LED support base having a number of surfaces corresponding to the number of the color layers of the color filter substrate, and LEDs of each color arranged on each surface of the LED support base. By moving the filter substrate to the irradiation surface of the LED of each color, the color filter substrate is sequentially illuminated with monochromatic light, and color unevenness of the color filter substrate is inspected for each color layer.

  In the present invention, it is preferable that the emission spectra of the LEDs of the respective colors do not overlap each other.

  In the present invention, the peak wavelength of the LED of each color can be set within a range of ± 10 nm of the peak wavelength of the transmittance spectral spectrum of the color layer of each color.

In the present invention, the color layer used in the color filter has n colors (n is an integer of 2 or more), and the peak wavelength of the n-color LED is λn and the full width at half maximum with respect to the emission spectrum of the LED. FWHM (n), peak wavelength of n + 1 color LED is λn + 1, full width at half maximum is FWHM (n + 1), peak wavelength of n-1 color LED is at λn-1, full width at half maximum is FWHM (n-1 ), The wavelength at the intersection of the n-color and n + 1-color spectra is λnn + 1, and the full width at half maximum of the portion where the n-color and n + 1-color spectra including the intersection overlap FWHM (nn + 1), the wavelength at the intersection of the n-color and n-1 color spectra is λnn-1, and the full width at half maximum of the portion where the n-color and n-1 color spectra including the intersection overlap is FWHM When (nn-1), the peak wavelength of the LED of each color is
λ (nn + 1) + (FWHM (nn + 1)) / 2+ (FWHM (n + 1)) / 2 ≦ λ (n + 1) ≦ 780,
λ (nn-1) + (FWHM (nn-1)) / 2+ (FWHM (n)) / 2 ≦ λn ≦ λ (nn + 1) − (FWHM (nn + 1)) / 2− (FWHM (n )) / 2,
380 ≦ λn−1 ≦ λ (nn-1) − (FWHM (nn-1)) / 2− (FWHM (n-1)) / 2
It can be set as the structure which satisfy | fills this relationship.

In the present invention, the color layers used for the color filter substrate are three colors of Red, Green, and Blue. Regarding the emission spectrum of the LED, the peak wavelength of the red LED is λr, and the full width at half maximum is FWHM. (r), the peak wavelength of the green LED is λg, the full width at half maximum is FWHM (g), the peak wavelength of the blue LED is λb, the full width at half maximum is FWHM (b), and the transmittance spectrum spectrum of the color filter substrate, Λgr is the wavelength at the intersection of the red and green spectra near 550 to 650 nm, FWHM (gr) is the full width at half maximum of the portion where the red and green spectra including the intersection overlap, and the green and blue wavelengths near 450 to 550 nm When the wavelength at the intersection of the spectrum is λbg, and the full width at half maximum of the portion where the green and blue spectra including the intersection overlap is FWHM (bg), the peak wavelength of the LED of each color is
λgr + (FWHM (gr)) / 2+ (FWHM (r)) / 2 ≦ λr ≦ 780nm,
λbg + (FWHM (bg)) / 2+ (FWHM (g)) / 2 ≦ λg ≦ λgr− (FWHM (gr)) / 2− (FWHM (g)) / 2
380 nm ≦ λb ≦ λbg− (FWHM (bg)) / 2− (FWHM (b)) / 2,
It can be set as the structure which satisfy | fills this relationship.

  In addition, the present invention uses a color filter inspection apparatus including at least an LED light source unit that illuminates a color filter substrate on which a plurality of color layers are formed with LEDs, and an LED light source control unit that controls the LED light source unit. In the color filter inspection method, LEDs having a number of colors corresponding to colors of the color layers of the color filter substrate are arranged in a matrix in the LED light source unit, and the LEDs of each color are sequentially arranged by the LED light source control unit. By turning on the light, the color filter substrate is sequentially illuminated with monochromatic light, and color unevenness of the color filter substrate is inspected for each color layer.

  In addition, the present invention uses a color filter inspection apparatus including at least an LED light source unit that illuminates a color filter substrate on which a plurality of color layers are formed with LEDs, and an LED light source control unit that controls the LED light source unit. A color filter inspection method, wherein the LED light source unit has a rotatable LED support base having a number of surfaces corresponding to the number of the color layers of the color filter substrate, and each color arranged on each surface of the LED support base And the LED light source controller rotates the LED support base to sequentially illuminate the color filter substrate with monochromatic light and inspect the color filter substrate for color unevenness for each color layer. Is.

  In addition, the present invention uses a color filter inspection apparatus including at least an LED light source unit that illuminates a color filter substrate on which a plurality of color layers are formed with LEDs, and an LED light source control unit that controls the LED light source unit. In the color filter inspection method, the LED light source unit includes an LED support base having a number of faces corresponding to the number of the color layers of the color filter substrate, and LEDs of each color arranged on each face of the LED support base; The color filter substrate is sequentially illuminated with monochromatic light by moving the color filter substrate to the irradiation surface of the LED of each color, and color unevenness of the color filter substrate is inspected for each color layer It is.

  As described above, the present invention uses a single color LED corresponding to each color layer of the color filter as an inspection light source in the visual inspection or visual inspection using an image pickup device such as a CCD that is performed during or after completion of the color filter manufacturing, and uses each color LED. Color unevenness can be easily identified in a short time by holding a color filter substrate in front of the LED light source unit and turning on the LEDs of each color while switching them on and performing a macroscopic appearance inspection. In addition, by using a single color light source of LED, there is less color mixture of transmitted light or reflected light that is visible than when using a white light source with a cold cathode tube, and the contrast of uneven portions of each color is increased. It is possible to detect subtle unevenness such as Therefore, by using such a color filter substrate with less unevenness, a liquid crystal display device with higher display quality can be realized.

  Various macro-like unevenness of the color filter substrate greatly affects the display uniformity of a liquid crystal display device or the like. However, it is difficult to discriminate color unevenness after the color filter substrate is completed by applying R, G, B, exposing, baking, and forming an overcoat or photo spacer as necessary. Often flows out and is discovered during R, G, B single color display pattern inspection in the panel inspection process. For example, in the final inspection process of a color filter substrate for a liquid crystal display device, an appearance inspection is performed using reflected light from a Na lamp or the like or transmitted light from a cold cathode fluorescent tube in order to detect macro unevenness. It is difficult to judge on the spot which color process is caused by Blue.

  This is a fluorescent lamp that includes all wavelength regions corresponding to Red, Green and Blue as inspection light sources, and a single-wavelength low-pressure sodium lamp (sodium D-line (588.995 nm, 589.592 nm)), because the inspection is performed with an orange-yellow light source with poor color rendering, the unevenness of a specific color is obstructed by the transmitted or reflected light of other colors, and the contrast of the unevenness portion is lowered. This is because the detection sensitivity is lowered.

  Therefore, in the present invention, R, G, and B single color LEDs corresponding to the R, G, and B primary colors used for the color filter substrate as a transmission inspection light source are separately turned on to perform a macro appearance inspection. For a monochromatic LED light source, an overlapping wavelength region is obtained by using an LED light source having a wavelength that avoids a region where the transmission spectrum of each color overlaps, such as the portion of the full width at half maximum FWHM (bg) in FIG. The transmitted light is limited to only the sub-pixel to be inspected. Thereby, since the contrast of the uneven portion of each color increases, it is possible to detect subtle unevenness that would otherwise be overlooked.

  In addition, when unevenness common to each color occurs, it can be easily detected by inspection using a conventional Na lamp or a white light source (cold cathode tube), but when unevenness specific to a certain color occurs, In the light source, transmitted light or reflected light of R, G, B is mixed and the contrast of the uneven portion cannot be obtained, so that detection becomes difficult.

  Therefore, in the present invention, in addition to using the single color LED as described above, the LED light sources of the respective colors are electrically switched without moving the color filter substrate from the front of the light box. As described above, by using the single color light source of the LED, there is almost no decrease in luminance when the inspection wavelength is switched and there is no waiting time loss until the luminance is stabilized, so that the color unevenness can be specified in a short time. Thereby, the state of unevenness in each color can be quickly compared, and irregular color unevenness can be detected with higher sensitivity than in the past.

  Further, in the above configuration, since a mechanical mechanism is not required, the inspection can be performed in a much shorter time than a method of obtaining a monochromatic light source with a white light source and a filter.

Further, since there is no mechanical mechanism, the reliability of the switching function can be improved. In addition, the LED light source has a longer life than a cold cathode tube and is almost maintenance-free, so the inspection process is less likely to be interrupted by non-lighting due to maintenance or failure, minimizing time loss due to replacement or maintenance, It can be kept in a constantly operating state. Therefore, the inspection time and the load on the inspector can be reduced, and the number of inspection processes per hour can be increased as compared with the conventional method.

  And by carrying out the above-described inspection, the eyes that see the unevenness of the color filter substrate become severe, and the pass / fail judgment level can be raised as necessary.

Therefore, the display uniformity of the liquid crystal display device can be improved by using a color filter substrate with a good unevenness level.

  The present invention inspects a single color LED corresponding to each color layer of a color filter substrate in visual inspection or visual inspection by an image pickup device such as a CCD performed during or after manufacture of the color filter substrate as shown in FIGS. It is used as a light source, and a color filter substrate is held in front of a light box using each single color LED, and each single color LED is lit while being switched separately to perform a macroscopic appearance inspection. As a result, the color mixture of transmitted light or reflected light is less visible than when a white light source using a cold cathode tube is used, and the contrast of uneven portions of each color is increased as shown in FIG. It is possible to detect subtle unevenness. As the monochromatic LED, an LED having an emission peak mainly in the red, green, and blue wavelength regions is used, but the type of LED to be used is increased or decreased in accordance with the color layer of the color filter substrate. For example, when Red, Yellow, Green, Cyan, and Blue are used for the color layer of the color filter substrate to be inspected, LEDs having five types of emission peaks are used.

  In order to describe the above-described embodiment of the present invention in more detail, a color filter inspection apparatus and a color filter inspection method according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 4 and FIG. To do. FIG. 1 is a diagram schematically illustrating the configuration of a transmission type color filter inspection apparatus according to the present embodiment, and FIG. 2 is a diagram schematically illustrating the configuration of a reflection type color filter inspection apparatus according to the present embodiment. FIG. 3 is a diagram schematically showing the configuration of an inspection LED light source light box of the color filter inspection apparatus, and FIG. 4 shows a state of color unevenness inspection using the color filter inspection apparatus of the present embodiment. FIG.

  As shown in FIG. 1 and FIG. 2, the color filter inspection apparatus (transmission type color filter inspection apparatus 1, reflection type color filter inspection apparatus 2) of the present embodiment is used for each monochromatic light irradiated to the color filter substrate 7 to be inspected. LED light source light box 3 for inspection, LED light source control system 4 for controlling LED light source light box 3 for inspection, CCD camera for detecting light transmitted or reflected by color filter substrate 7 to be inspected, etc. The imaging device 6 includes an imaging device control system that controls the imaging device 6 and processes imaging results, and an inspection processing system 5.

  The color filter inspection apparatus according to the present embodiment is characterized by a portion that generates light to be applied to the color filter substrate 7 to be inspected, and transmits light reflected or reflected by the color filter substrate 7 to be inspected. The configuration and control of the portion to be detected are not particularly limited. For example, the color unevenness may be inspected by an inspector without using the imaging device 6.

  As shown in FIG. 3, the inspection LED light source light box 3 according to the present embodiment includes an LED light source 10 in which LEDs emitting each single color light are arranged in a matrix, a drive power source 11 for driving the LED light source 10, and The LED light source drive circuit 12, a temperature sensor 16 and a temperature compensation circuit 13 for compensating for temperature changes of the LED light source 10, and a diffusion plate 14 and an optical film 15 that use light emitted from the LED light source 10 as a uniform light source Is done.

  The LED light source 10 to be used is one in which the emission spectra of the LEDs do not overlap each other. Regarding the wavelength, when the color layer used for the color filter substrate 7 is n colors, the peak wavelength of each monochromatic LED light source is a mixed color. In order to reduce, it selects and uses so that it may become the range of the following (1)-(3). At this time, the peak wavelength of each monochromatic LED light source is the one close to the peak wavelength of the transmittance spectral spectrum of each color resist (each color layer) used for the color filter substrate 7. More preferably, the peak wavelength of each monochromatic LED light source is within the range of ± 10 nm of the peak wavelength of the transmittance spectral spectrum of each color resist (each color layer). As a result, it has been confirmed that the color mixing of the light source can be sufficiently suppressed in practice, and the sensitivity at the time of color unevenness inspection of the color filter substrate 7 can be increased.

  λ (nn + 1) + (FWHM (nn + 1)) / 2+ (FWHM (n + 1)) / 2 ≦ λ (n + 1) ≦ 780 (1)

  λ (nn-1) + (FWHM (nn-1)) / 2+ (FWHM (n)) / 2 ≦ λ (n) ≦ λ (nn + 1) − (FWHM (nn + 1)) / 2− ( FWHM (n)) / 2 (2)

  380 ≦ λ (n-1) ≦ λ (nn-1) − (FWHM (nn-1)) / 2− (FWHM (n-1)) / 2 (3)

  In the above (1) to (3), the unit is nm, and n is 2 or more. Further, regarding the emission spectrum of the LED light source 10, the peak wavelength of the n-color LED light source is λn, the full width at half maximum is FWHM (n), the peak wavelength of the n + 1 color LED light source is λ (n + 1), and the full width at half maximum is FWHM. (n + 1), the peak wavelength of the n-1 color LED light source is λn−1, and the full width at half maximum is FWHM (n−1). Regarding the transmission spectrum of the color filter substrate 7, the wavelength at the intersection of the n-color and n + 1-color spectrum is λ (nn + 1), and the half value of the portion where the spectrum of the n-color and n + 1 color including the intersection overlaps. FWHM (nn + 1) for the full width, λ (nn-1) for the wavelength at the intersection of the n-color and n-1 colors, and the overlap of the n-color and n-1 spectra including the intersection The full width at half maximum is FWHM (nn-1).

  In this embodiment, the color layers used for the color filter substrate 7 are three colors of Red, Green, and Blue, and the peak wavelengths of the single color LED light sources 10 are the following (4) to (6). A range of ones was used. The spectrum at this time is shown in FIG.

  λgr + (FWHM (gr)) / 2+ (FWHM (r)) / 2 ≦ λr ≦ 780 nm (4)

  λbg + (FWHM (bg)) / 2+ (FWHM (g)) / 2 ≦ λg ≦ λgr− (FWHM (gr)) / 2− (FWHM (g)) / 2 (5)

  380 nm ≦ λb ≦ λbg− (FWHM (bg)) / 2− (FWHM (b)) / 2 (6)

  In the above (4) to (6), the unit was nm. As for the emission spectrum of the LED light source 10, the peak wavelength of the red LED light source is λr, the full width at half maximum is FWHM (r), the peak wavelength of the green LED light source is λg, the full width at half maximum is FWHM (g), and the blue LED The peak wavelength of the light source was λb, and the full width at half maximum was FWHM (b). Further, regarding the transmission spectrum of the color filter substrate 7, the wavelength at the intersection of the red and green spectra near 550 to 650 nm is λgr, and the half value of the portion where the red and green spectra including the intersection overlap (hatched portion) The full width is FWHM (gr), the wavelength at the intersection of the green and blue spectra near 450 to 550 nm is λbg, and the full width at half maximum of the part where the green and blue spectra including the intersection overlap (hatched area) is FWHM (bg ).

  More specifically, the LED light source 10 in which λr = 645 nm, FWHM (r) = 24 nm, λg = 530 nm, FWHM (g) = 37 nm, λb = 455 nm, and FWHM (b) = 28 nm was used. As the color filter substrate 7, λgr = 590 nm, FWHM (gr) = 13 nm, λbg = 493 nm, and FWHM (bg) = 25 nm were used.

  As an inspection method, a color filter substrate 7 is arranged in front of the LED light source light box 3 for inspection by an inspector or an inspection apparatus, and macroscopic visual confirmation of transmitted light or reflected light or CCD The image was input by the imaging device 6 and compared with the reference product, so that the state of unevenness was identified and the quality was determined.

  FIG. 4 shows a case where only Blue of the LED light source 10 is lit, and is a schematic diagram at the time of blue color unevenness inspection. Note that when inspecting red and green color unevenness, the inspector or the inspection apparatus inspected at the same position without moving by turning on the corresponding LED light sources.

  In this way, by switching the LED light source 10 of each color electrically without moving from the front of the LED light source light box 3 for inspection, the state of unevenness in each color can be quickly compared, and the irregular color Unevenness was detected with higher sensitivity than before. In addition, since the unevenness inspection is performed by using a single color light source, it is possible to avoid the decrease in contrast of the uneven portion due to the color mixture as shown in FIG. 7, so that it is possible to detect the irregular color unevenness with higher sensitivity than before.

  Then, using the color filter substrate 7 having a good unevenness level inspected in this way, the color filter substrate 7 and the TFT substrate are subjected to alignment treatment, and liquid crystal is dropped and bonded or liquid crystal is injected and sealed. Then, a polarizing plate or the like was attached to prepare a liquid crystal panel. Next, a liquid crystal display device was manufactured by attaching a peripheral drive circuit board and a backlight module. The liquid crystal display device thus completed has a better level of unevenness and higher display uniformity than the conventional liquid crystal display device.

  Next, a color filter inspection apparatus and a color filter inspection method according to a second embodiment of the present invention will be described with reference to FIG. FIG. 5 is a diagram schematically showing the configuration of an inspection LED light source light box of the color filter inspection apparatus of the present embodiment.

  As shown in FIG. 5, the inspection LED light source light box 3 of the present embodiment has a configuration in which each single color LED light source 10 is installed on each side of a triangular prism LED support base 17 that can be rotated by a predetermined drive mechanism. Other configurations are the same as those in the first embodiment. Here, since the light source has three colors, the LED support base 17 is a triangular prism. However, when the light source has four or more colors, a polygonal prism corresponding to the number of colors may be used. In FIG. 5, only the LED light source 10 is configured to rotate, but may be configured to rotate integrally with the diffusion plate 14 or integrally with the diffusion plate 14 and the optical film 15.

  When the color filter substrate 7 is inspected for color unevenness, the corresponding LED light source 10 is rotated in the direction of the emitted light and turned on, so that the inspector or the inspection apparatus can be inspected at the same position without moving. Went. Since the change of the light source of the illumination light for the inspection is mechanically performed, the switching time is longer than that in the first embodiment. However, since the rotation can be performed in a shorter time than the replacement of the color filter, it is sufficiently fast for inspection. Further, since the number of LEDs per color arranged per unit area is increased, it becomes possible to perform inspection with higher luminance.

  A liquid crystal display device was produced in the same manner as in Example 1 by using the color filter substrate 7 with a good unevenness level thus inspected. Also here, the level of unevenness was better and the display uniformity was higher than before.

  Next, a color filter inspection apparatus and a color filter inspection method according to a third embodiment of the present invention will be described with reference to FIG. FIG. 6 is a diagram schematically showing the configuration of the inspection LED light source light box of the color filter inspection apparatus of the present embodiment.

  As shown in FIG. 6, the inspection LED light source light box 3 of the present embodiment has a configuration in which each single-color LED light source 10 is installed on each side surface of the LED support base 17 having a trapezoidal cross section. Is the same as in Example 1. Here, since the light source has three colors, the cross section of the LED support base 17 has a trapezoidal shape. However, when the light source has four or more colors, it may have a cross sectional shape corresponding to the number of colors. In FIG. 6, the light shielding plate 18 is arranged so that the light of each color is not mixed, but the light shielding plate 18 may be omitted when illumination light with high directivity is obtained by the optical film 15 or the like.

  When the color unevenness inspection of the color filter substrate 7 is performed, the color filter substrate 7 is moved in the direction of the emitted light of the LED light source 10 corresponding to the color filter substrate 7 and the inspection is performed by an inspector or an inspection apparatus. Since the light-shielding plate 18 is installed between the LED light sources 10, it is possible to compare the color unevenness by always turning on or to turn on only the LED light source 10 of necessary inspection illumination light. Although the inspection time per one color filter substrate 7 increases due to the movement, a plurality of color filter substrates 7 can be inspected at the same time, so that the processing capability of the inspection process is equivalent to that of the second embodiment. In addition, since the number of LEDs arranged per unit area per color increases, it is possible to perform inspection with higher luminance.

  A liquid crystal display device was produced in the same manner as in Example 1 by using the color filter substrate 7 with a good unevenness level thus inspected. Also here, the level of unevenness was better and the display uniformity was higher than before.

  For comparison, a liquid crystal display device was manufactured based on a conventional example.

[Conventional example 1]
As shown in FIGS. 8 and 9, the color filter substrate 27 is inspected using the color filter inspection apparatuses 21 and 22 including the light box 23 using a three-wavelength type cold cathode tube as a light source. A liquid crystal display device was produced in the same manner as described above.

[Conventional example 2]
As shown in FIGS. 10 and 11, a color filter inspection device 21a including a light box 23 using a three-wavelength type cold cathode tube as a light source and a color filter switching device 29 capable of selecting the wavelength of the inspection illumination light by the color filter 28. 21b were used to inspect the color filter substrate 27, and a liquid crystal display device was fabricated in the same manner as in Example 1.

  Examples 1 to 3 and conventional examples 1 and 2, the unevenness level of the liquid crystal display device, the detection sensitivity of the uneven shape on the color filter substrate, the color unevenness detection sensitivity on the color filter substrate, the workability in inspection (inspection device Maintenance frequency, light source life, etc.) and inspection processing capacity were compared. The results are shown in Table 1. The levels were ranked as (good:）) >＞> Δ> (bad: x).

  Example 1 was superior in all cases. Even if the color of the inspection illumination light is switched by electrical switching of the LED light source, the luminance of each light source color does not decrease, and the instability of the luminance at the time of lighting as in the conventional three-wavelength type cold cathode tube There was no. In Example 2, the LED light source was rotated, and in Example 3, the color filter substrate was moved. As a result, the workability was inferior to that of Example 1. The level was the same as in Example 1.

  On the other hand, in the conventional example 1, since the inspection illumination light is white, the shape of unevenness can be seen, but the color unevenness cannot be determined. Further, when the color unevenness is light, it cannot be determined, and the light color unevenness is finally detected in the display inspection after the liquid crystal display device is completed. For this reason, in the color filter process, the outflow of the color unevenness failure could not be stopped. In Conventional Example 2, the detection of color unevenness can be detected in the inspection process of the color filter substrate, but since the luminance of the inspection illumination light is lowered by the color filter, the color unevenness detection sensitivity is higher than that of the embodiment using the LED light source. Also declined. In addition, it was necessary to replace the color filter at each inspection, and workability was inferior to that of Example 1.

  As described above, in the first to third embodiments, the unevenness level of the liquid crystal display device, the unevenness detection sensitivity of the color filter substrate, the color unevenness detection sensitivity of the color filter substrate, the workability in the color unevenness inspection, the color unevenness inspection processing. It was confirmed that any of the abilities was superior to the conventional examples 1 and 2, and the color unevenness could be easily detected with high sensitivity by employing the configuration of the present invention.

  In each of the above embodiments, the case where the color filter substrate of the liquid crystal display device is inspected by using the color filter inspection apparatus and the color filter inspection method of the present invention is shown. However, the present invention is limited to the above embodiments. Instead, the present invention can be similarly applied to the inspection of an arbitrary color filter substrate in which a multicolor pattern is arranged in the same plane.

  The present invention can be used for inspection of each color of a color filter in which a multicolor pattern is arranged on the same plane, such as a color filter for a liquid crystal display device, a color filter for a flat panel, and a color filter for a CCD. Further, the present invention can be used for a high-quality liquid crystal display device manufactured by the inspection, a field emission display device using a color filter, a fluorescent display device, a plasma display, and an imaging device.

It is a figure which shows typically the structure of the transmissive | pervious type color filter inspection apparatus which concerns on 1st Example of this invention. It is a figure which shows typically the structure of the reflection type color filter inspection apparatus which concerns on 1st Example of this invention. It is a figure which shows typically the structure of the LED light source light box for a test | inspection of the color filter test | inspection apparatus which concerns on 1st Example of this invention. It is the schematic at the time of the blue color nonuniformity test | inspection using the color filter test | inspection apparatus which concerns on 1st Example of this invention. It is a figure which shows typically the structure of the LED light source light box for a test | inspection of the color filter test | inspection apparatus concerning the 2nd Example of this invention. It is a figure which shows typically the structure of the LED light source light box for a test | inspection of the color filter test | inspection apparatus concerning the 3rd Example of this invention. It is a figure which shows the emission spectrum of the LED light source in the color filter test | inspection apparatus of this invention, and the transmission spectrum of a color filter. It is a figure which shows typically the structure of the conventional transmissive type color filter inspection apparatus. It is a figure which shows typically the structure of the conventional reflection type color filter inspection apparatus. It is a figure which shows typically the structure of the conventional transmissive type (with a color filter) color filter inspection apparatus. It is a figure which shows typically the structure of the conventional color filter inspection apparatus of a reflection type (with a color filter). It is the schematic at the time of the color nonuniformity test | inspection using the conventional color filter test | inspection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transmission type color filter inspection apparatus 2 Reflection type color filter inspection apparatus 3 LED light source light box for inspection 4 LED light source control system 5 Imaging apparatus control system and inspection processing system 6 Imaging apparatus 7 Color filter substrate 10 LED light source 11 Drive power supply 12 LED Light source drive circuit 13 Temperature compensation circuit 14 Diffusion plate 15 Optical film 16 Temperature sensor 17 LED support stand 18 Light shielding plate 21, 21a Transmission type color filter inspection device 22, 22a Reflection type color filter inspection device 23 Three-wavelength cold cathode light source 24 light source control system 25 imaging device control system and inspection processing system 26 imaging device 27 color filter substrate 28 color filter 29 color filter switching device

Claims (14)

A color filter inspection apparatus comprising at least an LED light source unit that illuminates a color filter substrate on which a plurality of color layers are formed with LEDs, and an LED light source control unit that controls the LED light source unit,
The LED light source unit is configured by arranging LEDs having the number of colors according to the color of the color layer of the color filter substrate in a matrix.
The LED light source control unit sequentially turns on the LEDs of each color, whereby the color filter substrate is sequentially illuminated with monochromatic light, and color unevenness of the color filter substrate is inspected for each color layer. Color filter inspection device. A color filter inspection apparatus comprising at least an LED light source unit that illuminates a color filter substrate on which a plurality of color layers are formed with LEDs, and an LED light source control unit that controls the LED light source unit,
The LED light source unit includes a rotatable LED support base having a number of surfaces corresponding to the number of the color layers of the color filter substrate, and LEDs of each color arranged on each surface of the LED support base,
The color filter substrate is sequentially illuminated with monochromatic light by rotating the LED support by the LED light source control unit, and color unevenness of the color filter substrate is inspected for each color layer. Filter inspection device. A color filter inspection apparatus comprising at least an LED light source unit that illuminates a color filter substrate on which a plurality of color layers are formed with LEDs, and an LED light source control unit that controls the LED light source unit,
The LED light source unit includes an LED support base having the number of surfaces corresponding to the number of the color layers of the color filter substrate, and LEDs of each color arranged on each surface of the LED support base,
By moving the color filter substrate to the irradiation surface of the LED of each color, the color filter substrate is sequentially illuminated with monochromatic light, and color unevenness of the color filter substrate is inspected for each color layer. Color filter inspection device.   The color filter inspection apparatus according to claim 1, wherein the emission spectra of the LEDs of the respective colors do not overlap each other.   The color filter inspection according to any one of claims 1 to 4, wherein the peak wavelength of the LED of each color is within a range of ± 10 nm of the peak wavelength of the transmittance spectrum of the color layer of each color. apparatus. The color layer used for the color filter is n colors (n is an integer of 2 or more),
Regarding the emission spectrum of the LED, the peak wavelength of the n-color LED is λn, the full width at half maximum is FWHM (n), the peak wavelength of the n + 1 color LED is λn + 1, the full width at half maximum is FWHM (n + 1), n−1. The peak wavelength of the color LED is λn-1, the full width at half maximum is FWHM (n-1),
Regarding the transmittance spectral spectrum of the color filter substrate, the wavelength at the intersection of the n-color and n + 1-color spectra is λnn + 1, and the full width at half maximum of the portion where the n-color and n + 1-color spectra including the intersection overlap is FWHM ( nn + 1), the wavelength at the intersection of the spectra of n and n−1 colors is λnn−1, and the full width at half maximum of the portion where the spectra of n and n−1 colors including the intersection overlap is FWHM (nn− 1)
The peak wavelength of the LED of each color is
λ (nn + 1) + (FWHM (nn + 1)) / 2+ (FWHM (n + 1)) / 2 ≦ λ (n + 1) ≦ 780,
λ (nn-1) + (FWHM (nn-1)) / 2+ (FWHM (n)) / 2 ≦ λn ≦ λ (nn + 1) − (FWHM (nn + 1)) / 2− (FWHM (n )) / 2,
380 ≦ λn−1 ≦ λ (nn-1) − (FWHM (nn-1)) / 2− (FWHM (n-1)) / 2
The color filter inspection apparatus according to claim 1, wherein the relationship is satisfied. The color layer used for the color filter substrate is three colors of Red, Green and Blue,
Regarding the emission spectrum of the LED, the peak wavelength of the red LED is λr, the full width at half maximum is FWHM (r), the peak wavelength of the green LED is λg, the full width at half maximum is FWHM (g), the peak wavelength of the blue LED is λb, The full width at half maximum is FWHM (b).
Regarding the transmittance spectrum spectrum of the color filter substrate, the wavelength at the intersection of the red and green spectra near 550 to 650 nm is λgr, and the full width at half maximum of the overlapping portion of the red and green spectra including the intersection is FWHM (gr ), When the wavelength at the intersection of the green and blue spectra near 450 to 550 nm is λbg, and the full width at half maximum of the portion where the green and blue spectra including the intersection overlap is FWHM (bg),
The peak wavelength of the LED of each color is
λgr + (FWHM (gr)) / 2+ (FWHM (r)) / 2 ≦ λr ≦ 780nm,
λbg + (FWHM (bg)) / 2+ (FWHM (g)) / 2 ≦ λg ≦ λgr− (FWHM (gr)) / 2− (FWHM (g)) / 2
380 nm ≦ λb ≦ λbg− (FWHM (bg)) / 2− (FWHM (b)) / 2,
The color filter inspection apparatus according to claim 1, wherein the relationship is satisfied. A color filter inspection method using a color filter inspection apparatus including at least an LED light source unit that illuminates a color filter substrate on which a plurality of color layers are formed with LEDs, and an LED light source control unit that controls the LED light source unit. And
In the LED light source unit, LEDs having the number of colors corresponding to the color of the color layer of the color filter substrate are arranged in a matrix,
The color light source controller sequentially turns on the LEDs of each color, thereby sequentially illuminating the color filter substrate with monochromatic light, and inspecting the color filter substrate for color unevenness for each color layer. Filter inspection method. A color filter inspection method using a color filter inspection apparatus including at least an LED light source unit that illuminates a color filter substrate on which a plurality of color layers are formed with LEDs, and an LED light source control unit that controls the LED light source unit. And
The LED light source unit is provided with a rotatable LED support base having a number of surfaces corresponding to the number of the color layers of the color filter substrate, and LEDs of each color arranged on each surface of the LED support base,
By rotating the LED support by the LED light source controller, the color filter substrate is sequentially illuminated with monochromatic light, and color unevenness of the color filter substrate is inspected for each color layer. Inspection method. A color filter inspection method using a color filter inspection apparatus including at least an LED light source unit that illuminates a color filter substrate on which a plurality of color layers are formed with LEDs, and an LED light source control unit that controls the LED light source unit. And
The LED light source unit is provided with an LED support base having the number of surfaces corresponding to the number of the color layers of the color filter substrate, and LEDs of each color arranged on each surface of the LED support base,
The color filter substrate is sequentially illuminated with monochromatic light by moving the color filter substrate to the irradiation surface of the LED of each color, and color unevenness of the color filter substrate is inspected for each color layer. Color filter inspection method.   The color filter inspection method according to any one of claims 8 to 10, wherein the LEDs of each color are selected so that their emission spectra do not overlap each other.   12. The color filter according to claim 8, wherein the peak wavelength of the LED of each color is set in a range within ± 10 nm of the peak wavelength of the transmittance spectral spectrum of the color layer of each color. Inspection method. The color layer used for the color filter is n colors (n is an integer of 2 or more),
Regarding the emission spectrum of the LED, the peak wavelength of the n-color LED is λn, the full width at half maximum is FWHM (n), the peak wavelength of the n + 1 color LED is λn + 1, the full width at half maximum is FWHM (n + 1), n−1. The peak wavelength of the color LED is λn-1, the full width at half maximum is FWHM (n-1),
Regarding the transmittance spectrum spectrum of the color filter substrate, the wavelength at the intersection of the n-color and n + 1-color spectra is λnn + 1, and the full width at half maximum of the portion where the n-color and n + 1-color spectra including the intersection overlap is FWHM ( nn + 1), the wavelength at the intersection of the spectra of n and n−1 colors is λnn−1, and the full width at half maximum of the portion where the spectra of n and n−1 colors including the intersection overlap is FWHM (nn− 1)
The peak wavelength of the LED of each color is
λ (nn + 1) + (FWHM (nn + 1)) / 2+ (FWHM (n + 1)) / 2 ≦ λ (n + 1) ≦ 780,
λ (nn-1) + (FWHM (nn-1)) / 2+ (FWHM (n)) / 2 ≦ λn ≦ λ (nn + 1) − (FWHM (nn + 1)) / 2− (FWHM (n )) / 2,
380 ≦ λn−1 ≦ λ (nn-1) − (FWHM (nn-1)) / 2− (FWHM (n-1)) / 2
The color filter inspection method according to claim 8, wherein the color filter inspection method is set so as to satisfy the relationship. The color layer used for the color filter substrate is three colors of Red, Green and Blue,
Regarding the emission spectrum of the LED, the peak wavelength of the red LED is λr, the full width at half maximum is FWHM (r), the peak wavelength of the green LED is λg, the full width at half maximum is FWHM (g), the peak wavelength of the blue LED is λb, The full width at half maximum is FWHM (b).
Regarding the transmittance spectrum spectrum of the color filter substrate, the wavelength at the intersection of the red and green spectra near 550 to 650 nm is λgr, and the full width at half maximum of the overlapping portion of the red and green spectra including the intersection is FWHM (gr ), When the wavelength at the intersection of the green and blue spectrum in the vicinity of 450 to 550 nm is λbg, and the full width at half maximum of the portion where the green and blue spectra including the intersection overlap is FWHM (bg),
The peak wavelength of the LED of each color is
λgr + (FWHM (gr)) / 2+ (FWHM (r)) / 2 ≦ λr ≦ 780nm,
λbg + (FWHM (bg)) / 2+ (FWHM (g)) / 2 ≦ λg ≦ λgr− (FWHM (gr)) / 2− (FWHM (g)) / 2
380 nm ≦ λb ≦ λbg− (FWHM (bg)) / 2− (FWHM (b)) / 2,
The color filter inspection method according to claim 8, wherein the color filter inspection method is set so as to satisfy the relationship.

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