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:
Mar. 19, 2002
Filed:
Dec. 12, 1997
Tatsundo Kawai, Hadano, JP;
Masami Tabata, Isehara, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
The form of a light condensing part of an illuminating device is of a freer form such as expressed by a general polynomial, rather than a round cross-sectional form. Accordingly, an illumination device or an image reading apparatus having the same which includes a light guide element having an entrance surface provided at one end thereof for an incident light flux, an exit surface provided on a side other than the one end extending in a longitudinal direction of the light guide element for allowing the incident light flux to exit therefrom, a reflecting and/or scattering area provided at a side other than the exit surface for reflecting and/or scattering the light flux propagated in a light-transmissive member, and a light condensing part provided on the exit surface for condensing the exiting light flux, and a light source provided adjacent to the entrance surface of the light guide element, wherein, assuming that in a cross-section orthogonally intersecting the longitudinal direction, a direction opposite to a normal line of the reflecting and/or scattering area is a z axis and a direction orthogonally intersecting the z axis is a y axis, at least a part of a surface of the light condensing part is expressed by a polynomial of y, and at least one of coefficients of odd-number-th degree terms in the polynomial is not “0”.