To provide a back projection type screen which is good in transmission efficiency and is slight in color shift by ameliorating the loss of the transmitted light in a diffusion sheet to diffuse light and a back projection type image display device which is slight in color shift, is excellent in resolution and transmission efficiency and is less degraded in contrast by external light.
A color shift correction sheet 36 arranged behind the diffusion sheet of the back projection type screen has array-like incident side lenticular lenses 361 which has the perpendicular direction as the longitudinal direction and three exist side lenticular lenses 362R, 362G and 362B which respectively copossess the foci with the incident side lenticualr lenses 361 facing the foci parts of the projected color of respective colors in correspondence to the respective incident side lenticular lenses 361, by which the projected light of the respective colors is made incident as parallel light beams perpendicular to the sheet surface of the diffusion sheet.
| JP2011043599 | VISUAL DISPLAY DEVICE |
| WO/2017/005726 | DEVICE FOR ILLUMINATING OBJECTS |
| JP2016011999 | IMAGE PROJECTION DEVICE |
IKEDA KENICHI
YAMAGISHI NARUMASA
