Reflection-type liquid crystal display device

• US 7,359,011 B2
• Filed: 03/26/2004
• Issued: 04/15/2008
• Est. Priority Date: 03/31/2003
• Status: Expired due to Fees

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Tashiro, Kunihiro, Suzuki, Toshihiro, Hamada, Tetsuya, Sugawara, Mari
• Primary Examiner(s): TON, MINH TOAN T
• Application Number:
  US10/810,483
• Publication Number:
  US 20040223094A1
• Time in Patent Office: 1,481 Days
• Field of Search: 349 63- 64, 349/112, 349/113, 362/561
• US Class Current: 349/63
• CPC Class Codes: G02B 6/0051 Diffusing sheet or layer
• CPC Class Codes: G02B 6/0056 for producing polarisation effects, e.g. by a surface with polarizing properties or by an additional polarizing elements
• CPC Class Codes: G02F 1/133504 Diffusing, scattering, diffracting elements associated to illuminating devices G02F1/133606
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/133541 Circular polarisers
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 1/133616 Front illuminating devices
• CPC Class Codes: G02F 1/13362 providing polarized light, e.g. by converting a polarisation component into another one
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation

Abstract

To suppress a decrease in the contrast caused by the reflection on the interface to the air layer without decreasing the quality of display. A reflection-type liquid crystal display device includes a light guide plate having a polarizing element stuck or adhered thereto on the side facing a reflection-type liquid crystal display panel, a source of light arranged on an end surface side of the light guide plate, and the reflection-type liquid crystal display panel arranged maintaining a predetermined gap relative to the light guide plate, wherein a light-diffusing function is imparted to the surface of the reflection-type liquid crystal display panel on the side facing the light guide plate.

Claims

1. A reflection-type liquid crystal display device comprising:

a light guide plate having a polarizing element stuck or adhered thereto on the side facing a reflection-type liquid crystal display panel, the polarizing element maintaining a predetermined air gap relative to the reflection-type liquid crystal display panel;

a source of light arranged on an end surface side of the light guide plate; and

a light-diffusing function imparted to the surface of the reflection-type liquid crystal display panel on the side facing the light guide plate,

wherein the reflection-type liquid crystal display panel has a rough surface on the side facing the light guide plate, and a haze (H) defined as an index represented by a ratio of a diffusion transmission factor (T_d) and a total light ray transmission factor (T_t) is given by;

H[%]=(T_d/T_t)×

100,

the haze being less than 50%.