Reflective polarizer module having light recycling improving sheet, and back light unit having same

A backlight unit comprising:

• a light guide plate having a light source disposed at one side of the light guide plate, and transmitting light generated from the light source;
• a reflection plate stacked on a lower surface of the light guide plate and reflecting the light transmitted through the light guide plate upwardly;
• an optical module comprising a diffusion sheet stacked on a top of the light guide plate to diffuse the light transmitted from below uniformly, and a second light collecting sheet, bonded to a top of the diffusion sheet, having a second structuring pattern having a second unit light collector, a cross-sectional area of which is reduced progressively upward, which is disposed continuously in a repetitive manner;
• and
• a reflective polarizer module comprising a first light collecting sheet including a first structuring pattern having a first unit light collector, a cross-sectional area of which is reduced progressively upward, which is disposed continuously in a repetitive manner, and collecting the light transmitted from below;
• a reflective polarizer sheet disposed in a stacked configuration on a top of the first light collecting sheet, and selectively transmitting the light by having a plurality of stacked layers having mutually different refractive indices;
• and a light recycling improving sheet disposed at a bottom of the reflective polarizer sheet, and randomly changing a polarized direction of the light which is not transmitted through the reflective polarizer sheet but is reflected downward,
• wherein the light having the polarized direction changed in the light recycling improving sheet moves downward and is reflected again from below to be transmitted to the reflective polarizer sheet.

A backlight unit comprising:

• a light guide plate having a light source disposed at one side of the light guide plate, and transmitting light generated from the light source;
• a reflection plate stacked on a lower surface of the light guide plate and reflecting the light transmitted through the light guide plate upwardly;
• an optical module comprising a diffusion sheet stacked on a top of the light guide plate to diffuse the light transmitted from below uniformly, and a second light collecting sheet, bonded to a top of the diffusion sheet, having a second structuring pattern having a second unit light collector, a cross-sectional area of which is reduced progressively upward, that is disposed continuously in a repetitive manner;
• and
• a reflective polarizer module comprising a reflective polarizer sheet having a first structuring pattern, disposed on an upper surface of the reflective polarizer sheet, having a first unit light collector, a cross-sectional area of which is reduced progressively upward, which is disposed continuously in a repetitive manner, and selectively transmitting the light by having a plurality of stacked layers having mutually different refractive indices;
• and a light recycling improving sheet disposed at a bottom of the reflective polarizer sheet, and randomly changing a polarized direction of the light which is not transmitted through the reflective polarizer sheet but is reflected downward,
• wherein the light having the polarized direction changed in the light recycling improving sheet moves downward and is reflected again from below to be transmitted to the reflective polarizer sheet.

A reflective polarizer module comprising:

• a reflective polarizer sheet selectively transmitting light by having a plurality of stacked layers having mutually different refractive indices;
• a light recycling improving sheet disposed at a bottom of the reflective polarizer sheet, and randomly changing a polarized direction of light which is not transmitted through the reflective polarizer sheet but is reflected downward;
• and
• a first light collecting sheet including a first structuring pattern having a first unit light collector, a cross-sectional area of which is reduced progressively downward from a lower surface of the light recycling improving sheet, which is disposed continuously in a repetitive manner, and collecting the light transmitted from below.

A backlight unit comprising:

• a light guide plate having a light source disposed at one side of the light guide plate, and transmitting light generated from the light source;
• a reflection plate stacked on a lower surface of the light guide plate and reflecting the light transmitted through the light guide plate upwardly;
• a diffusion sheet stacked on a top of the light guide plate to diffuse the light transmitted from below uniformly;
• and
• a reflective polarizer module comprising a reflective polarizer sheet selectively transmitting the light by having a plurality of stacked layers having mutually different refractive indices, a light recycling improving sheet disposed at a bottom of the reflective polarizer sheet, and randomly changing a polarized direction of light which is not transmitted through the reflective polarizer sheet but is reflected downward, and a first light collecting sheet including a first structuring pattern having a first unit light collector, a cross-sectional area of which is reduced progressively downward from a lower surface of the light recycling improving sheet, which is disposed continuously in a repetitive manner, and collecting the light transmitted from below,
• wherein the light having the polarized direction changed in the light recycling improving sheet moves downward and is reflected again from below to be transmitted to the reflective polarizer sheet.