Illlllllllllllllllllllllllllllllllllllllllllllllll
US006747716B2
(12) United States Patent ao) Patent No.: us 6,747,716 B2
Kuroiwa et al. (45) Date of Patent: *Jun. 8,2004
(54) OPTICAL ELEMENT INCLUDING AN
ABSORPTIVE AND REFLECTIVE
POLARIZER HAVING PARTICULAR
ORIENTATION
(75) Inventors: Masahiro Kuroiwa, Nagano (JP);
Naonori Miwa, Matsumoto (JP);
Atsunari Tsuda, Suwa (JP)
(73) Assignee: Seiko Epson Corporation, Tokyo (JP)
( * ) Notice: Subject to any disclaimer, the term ol this patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days.
This patent is subject to a terminal disclaimer.
(21) Appl. No.: 10/098,489
(22) Filed: Mar. 18, 2002
(65) Prior Publication Data
US 2002/0089622 Al Jul. 11, 2002
Related U.S. Application Data
(63) Continuation ol application No. 09/893,776, filed on Jun. 29, 2001, now Pat. No. 6,400,432, which is a continuation ol application No. 09/300,457, filed on Apr. 28, 1999, now Pat. No. 6,317,180.
(30) Foreign Application Priority Data
Apr. 30, 1998 (JP) 10-137430
(51) Int. CI.7 G02F 1/1335; G09G 3/36
(52) U.S. CI 349/96; 349/98; 349/112;
345/94
(58) Field of Search 349/96, 98, 117,
349/69, 112; 345/94
(56) References Cited
U.S. PATENT DOCUMENTS
5,686,979 A * 11/1997 Weber et al 349/96
5,986,730 A * 11/1999 Hansen et al 349/117
6,008,871 A * 12/1999 Okumura 349/113
6,096,375 A * 8/2000 Ouderkirk et al 359/485
6,124,971 A * 9/2000 Ouderkirk et al 359/487
6,262,842 Bl * 7/2001 Ouderkirk et al 349/114
6,291,035 Bl * 9/2001 Verrall et al 349/117
6,359,670 Bl * 3/2002 Broer et al 349/115
6,379,758 Bl * 4/2002 Hanmer et al 252/299.01
FOREIGN PATENT DOCUMENTS
WO WO 95/17699 6/1995
WO WO 98/00475 * 1/1998
* cited by examiner
Primary Examiner—Tarifur R. Chowdhury
(74) Attorney, Agent, or Firm—Obion, Spivak, McClelland,
Maier & Neustadt, PC.
(57) ABSTRACT
The liquid crystal device ol the present invention effectively prevents reversion ol bright/dark states between a reflective display mode and a transmissive display mode. The liquid crystal device includes a first absorptive polarizer, which receives light from outside; a liquid crystal cell, which receives light emitted from the first absorptive polarizer; a second absorptive polarizer, which receives light emitted from the liquid crystal cell; and a reflective polarizer, which receives light emitted from the second absorptive polarizer. The reflective polarizer has an axis of reflection in a predetermined direction to reflect at least part of light that has been transmitted through the first absorptive polarizer, the liquid crystal cell, and the second absorptive polarizer to be incident on the reflective polarizer. The reflective polarizer partially transmits light including a linearly polarized light component which is included in light entering the reflective polarizer from an opposite side to the second absorptive polarizer and which is to be transmitted through the second absorptive polarizer. The first absorptive polarizer has an axis of transmission in a specific direction to cause light, which has been reflected by the reflective polarizer and transmitted through the second absorptive polarizer, to be transmitted through the first absorptive polarizer.
10 Claims, 12 Drawing Sheets
