Method of manufacturing a lens sheet

Thick thickness of the resin sheet, to provide a production method by extrusion of a high aspect ratio lens sheet ridged lenses. A thermoplastic resin (A), the heat MFR than the thermoplastic resin (A) and a smaller thermoplastic resins (according to ISO 1133, 230 ° C., the value measured at a load of 37.3N) (B) extruding Te, made of a thermoplastic resin (a), the the volume per unit length y (y is a positive number), and a first layer is a surface layer, a second layer of thermoplastic resin (B) is and, x the volume per unit length to satisfy the following formula (1) (x is a positive number); the first step the multilayer sheet in the molten state obtained by the multi-manifold die with adjacent bets the shaping mold having a plurality of grooves, in close contact to the surface consisting of a first layer of the multilayer sheet of the resulting melt state in the first step, forming an n-number ridged lenses (n is a natural number) extrusion method for producing a lens sheet comprising: a second step of. 0.7 ≦ y / nx ≦ 2.0 (1)