PROBLEM TO BE SOLVED: To provide a laser device and an information acquisition device that are able to improve excitation efficiency by a simple configuration.SOLUTION: A laser device according to one embodiment of the present invention comprises: an active medium an excitation light source that emits excitation light for exciting the active medium a diffracting part with a periodic structure for deflecting excitation light and a resonator having at least two resonator reflectors for exciting light emitted by the active medium. A period of the periodic structure changes in a periodic direction of the diffracting part.SELECTED DRAWING: Figure 10COPYRIGHT: (C)2017,JPO&INPIT【課題】簡素な構成で励起効率を向上できるレーザ装置および情報取得装置を提供する。【解決手段】本発明の一実施形態に係るレーザ装置は、活性媒質と、活性媒質を励起するための励起光を射出する励起光源と、励起光を偏向するための周期構造を有する回折部と、活性媒質によって発せられる光を共振させる少なくとも2つの共振器反射鏡を有する共振器と、を備え、回折部における周期方向に沿って周期構造の周期が変化している。【選択図】図10
