Dainippon Screen Mfg. Co., Ltd.

Screen Holdings Co., Ltd.

Makoto Narazaki

Takashi Sakamoto

Takaharu Yamamoto

Hiroshi Asai

Toru Kawada

Kiyoomi Mitsuki

Kazutaka Taniguchi

Yuji Kurokawa

Yusaku Ikeda

Yuya Takagi

Yoshikazu Masuda

Minoru Komatsu

Noriyoshi Yamashita

In a threshold matrix generation method, after periodic areas are set in a matrix space and elements existing every other one in a row direction and a column direction in each periodic area is set as target elements, performed is a step of assigning threshold values ranging from one on the most highlight side to a predetermined switching threshold value sequentially to target elements in the periodic areas. Assuming that elements to which threshold values are assigned are regarded as determined elements, in the step, under a condition that the number of determined elements is almost same in the periodic areas and each determined element is positioned in a vicinity of any one determined element in each periodic area, a target element whose distance to all determined elements is largest is specified within the periodic areas and a threshold value is assigned to the target element.

Threshold matrix generation method, image data generation method, storage medium storing program, threshold matrix, and image data generation apparatus

In a printing apparatus, a colorimeter is provided for performing imaging calibration on an inline scanner for inspecting a printed image. During a printing operation, the inline scanner captures a test pattern image formed on paper and thereby obtains calibration imaging data, the colorimeter performs color measurement on the test pattern image and thereby obtains calibration colorimetric data, both data are used to update a correction factor LUT for imaging calibration, and the correction factor LUT is used to perform imaging calibration on the inline scanner.

Printed image inspection device and printing apparatus including same

An inkjet printer includes an image-forming part, forming an auxiliary layer on a base material by ejecting droplets of auxiliary ink and forming an image on the auxiliary layer by ejecting droplets of image-forming ink, the auxiliary ink changing a dot formation state of droplets of the image-forming ink. In a storage part, a reference table that associates each of a plurality of types of base materials with a proper dot area rate to be used when forming the auxiliary layer is stored. In a dot-area-rate determination part, a dot area rate to be used when forming the auxiliary layer on a target base material is determined as an auxiliary ink dot area rate by referencing the reference table using the type of the target base material. This enables the inkjet printer to form a highly precise image on various base materials.

Inkjet printer and method for forming an auxiliary layer based on medium type

A CPU assumes a virtual color monitor in which actual chromaticity coordinates of colors expressed by fluorescent materials are replaced by virtual chromaticity coordinates having the same hues as those of the actual chromaticity coordinates but higher saturations than those of the actual chromaticity coordinates. The CPU converts colorimetric values X, Y, and Z into luminance-linear values r&prime;, g&prime;, and b&prime; for red, green, and blue, based on a relationship of color conversion for the virtual color monitor at step S . The CPU then sets any one of the values r&prime;, g&prime;, and b&prime; to L at step S and compares the value L with i at step S , where i is the &ggr;-th power of j and greater than 0. In case that the value L is less than i, the CPU calculates a value c based on the remaining values other than the value L among the values r&prime;, g&prime;, and b&prime; at step S . When &minus;ck&lE;L<0, conversion of the value L into V is carried out according to a linear function of L, in which an L intercept is varied with a variation of the value c, at step S . In case that the value L is not less than i, on the other hand, the CPU carries out conversion of the value L into V according to a function of 1/&ggr;-th power of L at step S . At subsequent step S , the CPU sets the value V thus obtained to one of display signals R, G, and B corresponding to one of the values r&prime;, g&prime;, and b&prime; set at step S . This color conversion process effectively prevents abnormal tone or a change in hue in an area of a desired color that is out of a reproducible color range.

Method of color conversion, apparatus for the same, and computer program product for realizing the method

The present invention relates to an image reader 3 which reads the reflected light obtained by lightening from underneath a transparency board 6 on which an image original is placed, especially a cover 30 for the image reader 3 for adjusting the bend of the image original. The cover 30 comprise a vacuum pump (not shown) for reducing the air pressure in the space formed by the transparency board 6 and a bend member 48 and an airtight member 50. Therefore the image reader 3 utilizing the cover 30 can correctly read image on both a transparency original and a reflection original, and yet be easy to manipulate when reading the reflection original.

Cover for adjusting the bend of an original

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Kyoto, Japan

Makoto Narazaki