PROBLEM TO BE SOLVED: To provide a fluorescence observation device with which a region comprising a large number of fluorescent substances is specified without complex calculations being performed, even when the intensity of fluorescence changes due to distance or angle.SOLUTION: The fluorescence observation device (1) is provided comprising: an illumination unit (3) which illuminates a subject (A) with excitation light and illumination light a fluorescent imaging unit (18) which acquires a fluorescence image (S2) by capturing an image of fluorescence generated in the subject (A) as a result of illumination with the excitation light from the illumination unit (3) a return-light imaging unit (17) which acquires a return-light image (S1) by capturing an image of the return-light that returns from the subject (A) due to illumination with the illumination light from the illumination unit (3) a region extraction unit (24) which extracts a high-brightness region where the fluorescence image (S2) acquired by the fluorescent imaging unit (18) has a gradation value of at least a set threshold value (S4) and a threshold setting unit (22) which increases the threshold value (S4) in response to increases in the gradation value of the return-light image (S1) acquired by the return-light imaging unit (17).COPYRIGHT: (C)2012,JPO&INPIT【課題】距離や角度により蛍光強度が変化した場合でも、複雑な演算を行うことなく蛍光物質が多く存在する領域を特定する。【解決手段】被写体Aに対し、励起光および照明光を照射する照明部3と、該照明部3からの励起光の照射により前記被写体Aにおいて発生した蛍光を撮影し蛍光画像S2を取得する蛍光撮像部18と、照明部3からの照明光の照射により被写体Aから戻る戻り光を撮影し戻り光画像S1を取得する戻り光撮像部17と、蛍光撮像部18により取得された蛍光画像S2が、設定された閾値S4以上の階調値を有する高輝度領域を抽出する領域抽出部24と、戻り光撮像部17により取得された戻り光画像S1の階調値が高いほど閾値S4を高く設定する閾値設定部22とを備える蛍光観察装置1を提供する。【選択図】図1
