LCD device including an illumination device having a polarized light separating sheet between a light guide and the display

An illumination device for a direct viewing type display element, comprising:

• a flat light guide;
• a light source set such that light is incident on a side portion of said flat light guide;
• a polarized light separating sheet set on a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to light rays substantially having a predetermined direction of incidence;
• and
• a light reflecting sheet disposed on another side opposite to and facing said light emitting side of the flat light guide in parallel with the emitting side, said light reflecting sheet converting said portion of s polarized light component reflected by said polarized light separating sheet into p polarized light and reflecting the converted p polarized light to said polarized light separating sheet for transmission of the converted p polarized light through said polarized light separating sheet in overlapping relationship with the p polarized light component.

An illumination device for a direct viewing type display element, comprising:

• a flat light guide;
• a light source set such that light is incident on a side portion of said flat light guide;
• a polarized light separating sheet set on a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to a light ray substantially having a predetermined direction of incidence;
• and
• a light reflecting sheet disposed on another side opposite to and facing said light emitting side of the flat light guide in parallel with the emitting side, wherein said polarized light separating sheet is planar and parallel to the light emitting side of the flat light guide and is set in proximity to the flat light guide in the light emitting direction.