Reflection screen and image display system

A reflection screen adapted to reflect image light projected from an image source to display an image in a viewable manner, the reflection screen comprising:

• a lens layer provided on a back side thereof with a Fresnel lens shape having an array of a plurality of unit lenses provided on the back side, the unit lenses each having a lens surface and a non-lens surface and being protuberant toward the back side;
• a reflection layer adapted to reflect light, the reflection layer formed at least on the lens surfaces of the unit lenses;
• and
• a surface lens layer disposed on the reflection screen on the side of the image source, the surface lens layer having a lenticular lens shape provided on the image source side, the lenticular lens shape provided at an image-source-side surface thereof with a plurality of unit surface lenses each protuberant toward the image source side, the unit surface lenses being arrayed in a screen left-right direction of the reflection screen, with their longitudinal direction set in the screen up-down direction of the reflection screen;
• wherein the Fresnel lens shape has an optical center located outside of a screen of the reflection screen,
• wherein the unit surface lenses are each so shaped that the width thereof in the array direction is not less than the height thereof, and
• wherein the unit surface lens is so configured that,
• in a section parallel to the array direction of the unit surface lens and parallel to a thickness direction of the reflection screen,
• an angle that a tangent to a bottom-part-side surface of the unit surface lens makes with the screen plane is greater than an angle that a tangent to an apex-part-side surface of the unit surface lens makes with the screen plane, and
• a variation, per a predetermined length, of the angle that the tangent to the bottom mart-side surface of the unit surface lens makes with the screen plane is greater than a variation, per the predetermined length, of the angle that the tangent to the apex-part-side surface of the unit surface lens makes with the screen plane.