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:
Jan. 23, 2007
Filed:
Apr. 21, 2000
Hiroyuki Mori, Minami-ashigara-shi, Kanagawa, 250-0123, JP;
Hiroaki Sata, Minami-ashigara-shi, Kanagawa, 250-0123, JP;
Hiroyuki Mori, Minami-ashigara-shi, Kanagawa, 250-0123, JP;
Hiroaki Sata, Minami-ashigara-shi, Kanagawa, 250-0123, JP;
Other;
Abstract
A phase retarder comprises one cellulose ester film. The retardation value of the film represented by Re450 measured at the wavelength of 450 nm is in the range of 100 to 125 nm. The retardation value of the film represented by Re590 measured at the wavelength of 590 nm is in the range of 120 to 160 nm. The retardation values represented by Re450 and Re590 satisfy the condition of Re590−Re450≧2 nm. An aromatic compound having at least two aromatic rings is incorporated in the film as a retardation increasing agent to obtain λ/4 in the wide wavelength region defined above. A phase retarder can also give λ/2 in a wide wavelength region in the same manner.