The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 23, 2010
Filed:
Jun. 28, 2005
Kosei Takahashi, Kanagawa, JP;
Osamu Yamada, Tokyo, JP;
Kosei Takahashi, Kanagawa, JP;
Osamu Yamada, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A spectral distribution error evaluation apparatus is used to evaluate precision of color matching between evaluation and target colors. A first weighting function generator generates a first weighting function on the basis of color matching functions, wavelength characteristics which are independent of a light source of the target color, and visual characteristics which depend on wavelengths. A second weighting function generator generates a second weighting function on the basis of light source information of selected light sources. A difference calculator calculates error values between the evaluation and target colors for respective frequencies. An evaluation value calculator applies the first and second weighting functions to the error values, and calculates the sum total of the error values as an evaluation value. In this way, a precision evaluation value which has high correlation with actual color appearance and is used to improve the color matching precision can be calculated independently of a change in condition such as a light source or the like.