| 摘要 |
PROBLEM TO BE SOLVED: To provide a light observation device capable of easily obtaining an observation optical image of an irradiation part even when a condensing position of modulated light is changed in an optical axis direction.SOLUTION: A light observation device 1A includes: a spatial light modulator 20 which displays a Fresnel kinoform on a phase modulation plane 20a and which applies modulated light L2 to an observation object B after modulating a phase of light L1; an imaging optical system 15 imaging observed light L3 from the observation object B; an optical system moving mechanism 16 moving the imaging optical system 15 in an optical axis direction of the observed light L3; and a controller 19 controlling the optical system moving mechanism 16 in such a manner that a focal position of the imaging optical system 15 changes corresponding to a change of the condensing position of the modulated light L2 due to the Fresnel kinoform. |
