| 摘要 |
PROBLEM TO BE SOLVED: To provide a light beam control sheet which can reduce the constituent members of a back light unit while maintaining the sharpness of the display screen of a liquid crystal display device and is also usable for a long period. SOLUTION: The light beam control sheet 1a used for the back light unit of the liquid crystal display device is provided with space parts 2 and 3. The space parts 2 and 3, etc., are constituted including 1st flanks 2a and 3a and the 1st flank 2a is formed into a slanting surface having its lower end 2e positioned on the left side of the upper end 2f in the right-left direction B. Then a light beam which is made incident obliquely in the slantingly right upper direction from the lower side in the up-down direction A and travels from the left side to the 1st flank 2a is emitted from the top surface almost to right above. |
