Liquid crystal display device

A liquid crystal display device comprising:

• a liquid crystal display panel having a rear surface and a display surface on a side opposite the rear surface, for modulating light entering from the rear surface to generate image light and outputting the image light from the display surface;
• a first backlight unit for illuminating the rear surface of the liquid crystal display panel with light;
• a second backlight unit for radiating light toward a rear surface of the first backlight unit;
• a first light source driving and control unit for controlling the amount of light emitted by the first backlight unit;
• and
• a second light source driving and control unit for controlling the amount of light emitted by the second backlight unit;
• wherein
• the first backlight unit includes
• a first light source controlled by the first light source driving and control unit,
• a first optical member for transmitting the light radiated by the second backlight unit, and for converting light output by the first light source to light having a narrow-angle directional distribution in which light having a predetermined or greater intensity is localized to a first angular range centered on a direction normal to the display surface of the liquid crystal display panel and radiating the converted light toward the liquid crystal display panel, and
• a first optical sheet for transmitting the light radiated by the second backlight unit and for reflecting, toward the first optical member, by total internal reflection, light radiated from a side of the first optical member facing oppositely away from the liquid crystal display panel;
• the second backlight unit includes
• a second light source controlled by the second light source driving and control unit, and
• a second optical member for converting light output from the second light source to light having a wide-angle directional distribution in which light having a predetermined or greater intensity is localized to a second angular range wider than the first angular range, and radiating the converted light toward the rear surface of the first backlight unit;
• and
• the first optical member and the first optical sheet transmit the light radiated from the second optical member without narrowing the wide-angle directional distribution of the light radiated from the second optical member.

A liquid crystal display device comprising:

• a liquid crystal display panel having a rear surface and a display surface on a side opposite the rear surface, for modulating light entering from the rear surface to generate image light and outputting the image light from the display surface;
• a first backlight unit for illuminating the rear surface of the liquid crystal display panel with light;
• a second backlight unit for radiating light toward a rear surface of the first backlight unit;
• a first light source driving and control unit for controlling the amount of light emitted by the first backlight unit;
• and
• a second light source driving and control unit for controlling the amount of light emitted by the second backlight unit;
• wherein
• the first backlight unit includes
• a first light source controlled by the first light source driving and control unit, and
• a first optical member for transmitting the light radiated by the second backlight unit, and for converting light output by the first light source to light having a first directional distribution in which light having a predetermined or greater intensity is localized to a first angular range centered on a direction normal to the display surface of the liquid crystal display panel and radiating the converted light toward the liquid crystal display panel;
• the second backlight unit includes
• a second light source controlled by the second light source driving and control unit, and
• a second optical member for converting light output from the second light source to light having a second directional distribution in which light having a predetermined or greater intensity is localized to a second angular range centered on the direction normal to the display surface of the liquid crystal display panel, and radiating the converted light toward the rear surface of the first backlight unit;
• and
• the first optical member converts the light radiated from the second optical member to light having a third directional distribution in which light having a predetermined or greater intensity is localized to a third angular range centered on a direction inclined at a predetermined angle from the direction normal to the display surface of the liquid crystal display panel, and radiates the converted light toward the liquid crystal display panel.