Backlight device and liquid crystal display

A liquid crystal display apparatus having a light transmitting liquid crystal display panel and a backlight device for illuminating said liquid crystal display panel from the back side thereof, said backlight device comprising:

• a light source, made up by a plurality of cold cathode ray tubes;
• and
• a light diffusing plate arranged in the light radiating direction of said light source for facing said light source, said light diffusing plate having a transmittance for all light rays of 62 to 71% and a cloud value of 90 to 99% and carrying a light dimming dot pattern thereon;
• said dots of said light dimming dot pattern being formed on said light diffusing plate lying at a location corresponding to division by 24 to 48 of the spacing between neighboring ones of said cold cathode ray tubes, with the diameter of said dots being 0.16 to 0.7 mm depending on the distance from said cold cathode ray tubes.

A backlight device comprising

• a light source made up by a plurality of light emitting diodes, radiating red light, green light and blue light;
• and
• a light diffusing light guide plate arranged in the direction of light projection of said light source, said light diffusing light guide having a transmittance for all light rays of 50 to 93% and a cloud value of 70% to 93%, said light diffusing light guide plate carrying a light dimming dot pattern and configured for mixing the red light, green light and blue light incident thereon;
• wherein
• dots of said light dimming dot pattern are formed facing said light emitting diodes on said light diffusing light guide plate with one-for-one correspondence to said light emitting diodes so that the dot shape is symmetrical or non-symmetrical relative to the center of light emission of said light emitting diode, with the area of each dot being 28 to 86 mm2.

A liquid crystal display apparatus including a light transmitting liquid crystal display panel and a backlight device for illuminating liquid crystal display panel from the back side thereof, said apparatus comprising

• a light source made up by a plurality of light emitting diodes, radiating red light, green light and blue light;
• and
• a light diffusing light guide plate arranged in the direction of light projection of said light source, for facing said light source, said light diffusing guide plate having a transmittance for all light rays of 50 to 93% and a cloud value of 70% to 93%, said light diffusing light guide plate carrying a light dimming dot pattern and configured for mixing the red light, green light and blue light incident thereon;
• wherein,
• dots of said light dimming dot pattern are formed facing said light emitting diodes on said light diffusing light guide plate with one-for-one correspondence to said light emitting diodes so that the dot shape is symmetrical or non-symmetrical relative to the center of light emission of said light emitting diode, with the area of each dot being 28 to 86 mm2.