TRANSPARENT BASE MATERIAL FILM LAMINATE, TOUCH PANEL SENSOR FILM, TOUCH PANEL, IMAGE DISPLAY DEVICE, AND METHOD FOR IMPROVING VISIBILITY OF IMAGE DISPLAY DEVICE

Provided is a transparent base material film laminate that is used while disposed on the viewing side of a polarizing plate of an image display device having a backlight light source and the polarizing plate. The laminate has a first transparent base material film and a second transparent base material film. The Re of the first transparent base material film is 4000 nm or higher. The laminate is disposed for use such that an angle formed by a slow axis of the first transparent base material film and an absorption axis of the polarizing plate is 45°±20° and such that an angle formed by a slow axis of the second transparent base material film and the absorption axis of the polarizing plate is 90°±30° or 0°±30°. An angle formed by the slow axes of the first transparent base material film and the second transparent base material film is neither 0° nor 90°. The second transparent base material film is used while disposed on the viewing side relative to the first transparent base material film. The present invention also provides: a touch panel sensor film; a touch panel; an image display device; and a method for improving the visibility of an image display device.