OPTICAL SYSTEM

To provide an optical system which can make the peak of the luminous intensity of emitted light closer to a wide angle side than before while suppressing the reduction of light quantity even when an obstacle such as a partition wall for separating a normal light source is present outside a lens in the optical system used as the emergency light.SOLUTION: Disclosed is an optical system arranged in a housing part having a wall part separating the housing part from a regular light source and used as the emergency light which includes: a light source having a square light-emitting surface in which four light-emitting parts are arranged vertically and horizontally in two rows; a lens which is formed in a rotationally symmetric shape, has the incident surface on which light is incident and the emission surface from which light is emitted, and deflects the light emitted from the light source so as to avoid the wall part; and a socket for fixing the light source and the lens so that the center axis of the lens and the optical axis of the light source coincide with each other.SELECTED DRAWING: Figure 1 【課題】非常灯として用いられる光学系において、レンズの外側に常用光源と隔てる隔壁等の障害物がある場合でも光量の低下を抑制しつつ、従来よりも出射光の光度のピークを広角側にできる光学系を提供すること。【解決手段】光学系は、常用光源との間を隔てる壁部を有した収容部に配置され、非常灯として用いられる光学系であって、４つの発光部が縦と横にそれぞれ２列配置され構成された四角形状の発光面を有する光源と、回転対称形状に形成され、光が入射する入射面と光が出射する出射面とを有し、光源から放射した光が壁部を回避するように偏向するレンズと、レンズの中心軸と光源の光軸とが一致するように、光源とレンズとを固定するソケットと、を備えたものである。【選択図】図１