There is provided: an optical sheet, which has excellent productivity while maintaining an optical performance and can reduce a manufacturing cost; an image source unit; a display device; a method for producing an optical sheet; and a method for manufacturing a display device. The bi-level data is rendered to a dot level and subsequently compressed in the personal computer. Peptides of the invention may be directed against any glycosaminoglycan, including hyaluronic acid, chondroitin sulfate A, chondroitin sulfate C, dermatan sulfate, heparin, keratan sulfate, keratosulfate, chitin, chitosan 1, and chitosan 2.