BACK PROJECTION TYPE SCREEN AND IMAGE DISPLAY DEVICE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To bring a Fresnel lens sheet which constitutes a back projection type screen and a diffusion sheet into permanent contact with each other so that they will not float in a high-temperature and high-humidity atmosphere. SOLUTION: The image observation side of the diffusion sheet (8) is made of material whose expansion by water absorption is smaller than that of the main material of the diffusion sheet (8) and covered with a 2nd protection sheet (9) which is thinner than the diffusion sheet (8); and the image formation side of the Fresnel lens sheet (6) is made of material whose expansion by water absorption is smaller than that of the main material of the Fresnel lens sheet (6) and covered with a 1st projection sheet (7) which is thinner than the Fresnel lens sheet (6).