| 摘要 |
In a fluorescence viewing device (1A), a clear observation image from which the effect of background light has been removed can be acquired by taking the difference between one of a first frame image and a second frame image outputted from an imaging device (12) and the other of the first frame image and second frame image which is stored in an image storage means. In the fluorescence viewing device (1A), the exposure time for a fluorescence image acquisition period and the exposure time for a background image acquisition period are different from each other. By thus making the exposure time for the fluorescence image acquisition period and the exposure time for the background image acquisition period asymmetric, the observation image is endowed with good smoothness. Since the ON/OFF time of excitation light is also asymmetric in accordance with the asymmetry of the exposure times, discomfort to a user due to flickering of the excitation light can be reduced. |
