The present invention provides a Fresnel lens sheet that scarcely makes
the projected image distorted, and others. The Fresnel lens sheet has a
plurality of unit total reflection Fresnel lenses arranged on the
light-entering side, each unit lens having a light-entering surface and a
total reflection surface that totally reflects a part of or all of the
imaging light that has passed through the light-entering surface to
deflect the light in the desired direction. This Fresnel lens sheet is
formed so that it fulfills the relationship
H.sub.1.times.H.sub.1/(10.times.E.sub.1.times.T.sub.1.times.T.sub.1).ltor-
eq.3L/2000, where H.sub.1 represents the length (cm) in the vertical
direction of the Fresnel lens sheet; L.sub.1, the length (cm) in the
horizontal direction of the Fresnel lens sheet; T.sub.1, the thickness
(cm) of the Fresnel lens sheet; and E.sub.1, the modulus of elasticity
(kgf/cm.sup.2) of the Fresnel lens sheet. Further, by using, to make up
the Fresnel lens sheet, a Fresnel-lens-molded sheet having unit total
reflection Fresnel lenses and a backing sheet laminated to the
light-emerging surface of the Fresnel-lens-molded sheet, improvement in
the efficiency of mold releasing operation that is conducted in the
production of the Fresnel lens sheet is achieved.