Backlight unit, liquid-crystal display apparatus, and stacked structure

A liquid-crystal display apparatus comprising:

• a liquid-crystal display panel, a reflective polarizing plate, a ¼-wavelength plate that applies a retardation of ¼ wavelength to transmission light, a light-diffusing sheet, a light control sheet that controls directivity of transmission light, and a light guide plate, which are sequentially stacked,
• wherein the ¼-wavelength plate exhibits reverse wavelength dispersion characteristics with respect to light reflected from the reflective polarizing plate so that a retardation applied to transmission light increases as the wavelength of the transmission light increases,
• the light control sheet is a prism sheet formed of a material having refractive-index isotropy,
• wherein the prism sheet and the ¼-wavelength plate are integrated with each other
• wherein the light control sheet is a prism sheet in which a convex structure having a polygonal cross-sectional shape is repeatedly formed on a light entrance surface or a light exit surface,
• wherein the prism sheet and the light diffusing sheet are formed of a material having refractive-index isotropy,
• whereby light which has been reflected from the reflective polarizing plate and has passed through the ¼-wavelength plate and the light which has been output from the light guide plate and enters the ¼-wavelength plate are suppressed from experiencing a retardation in the in-plane direction of the ¼-wavelength plate.

A liquid-crystal display apparatus comprising:

• a liquid-crystal display panel, a reflective polarizing plate, a ¼-wavelength plate that applies a retardation of ¼ wavelength to transmission light, a light-diffusing sheet, a light control sheet that controls directivity of transmission light, and a light guide plate which are sequentially stacked,
• wherein the ¼-wavelength plate exhibits reverse wavelength dispersion characteristics with respect to light reflected from the reflective polarizing plate so that a retardation applied to transmission light increases as the wavelength of the transmission light increases,
• the light control sheet is formed of a material having refractive-index isotropy, and
• wherein the light control sheet is a prism sheet in which a convex structure having a polygonal cross-sectional shape is repeatedly formed on a light entrance surface,
• wherein the prism sheet and the light diffusing sheet are formed of a material having refractive-index isotropy,
• whereby light which has been reflected from the reflective polarizing plate and has passed through the ¼-wavelength plate and the light which has been output from the light guide plate and enters the ¼-wavelength plate are suppressed from experiencing a retardation in the in-plane direction of the ¼-wavelength plate.