The present invention cheaper manufacturing cost, it is possible to a large area, during flexion obtaining an optical film excellent in durability and is high temperature and humidity when the film. A having a dielectric multi-layer film comprising an organic polymer, it is achieved by narrow band-pass filter. .BACKGROUND 1【課題】製造コストが安く、大面積化が可能であり、屈曲時や高温高湿時の膜の耐久性に優れる光学フィルムを得ること。【解決手段】有機ポリマーを含む誘電多層膜を有する、狭帯域バンドパスフィルターにより達成される。【選択図】図1