PROBLEM TO BE SOLVED: To provide a surgical microscope allowing an operator to observe an object by the naked eye, to observe a visible light image and to observe a fluorescent image in a weak near-infrared wavelength band without reducing the quantity of light and to provide a surgical microscope adjustable the ratio of the quantity of light passing through respective observation light paths without detaching a second light-splitting element from a light path in a structure of two observation light paths divided via the second light-splitting element disposed in the light path other than a main operator.SOLUTION: The surgical microscope includes a naked eye observation optical system 1 for observing the object for observation 3 by the naked eye an imaging optical system 2 for imaging the object 3 for observation and the light splitting element 4 for splitting the light from the object 3 for observation into the light passing through the light path of the naked eye observation optical system 1 and the light passing through the light path of the imaging optical system. The imaging optical system 2 is disposed on the transmitting side of the light fractionation element 4. The light splitting element 4 has a fixed transmittance in a visible wavelength band, and a higher transmittance in the near-infrared wavelength band than in the visible wavelength band.COPYRIGHT: (C)2010,JPO&INPIT【課題】肉眼での観察とともに可視光画像の観察をすることができ、微弱な近赤外波長帯域での蛍光画像を光量を落とすことなく観察できる手術用顕微鏡、さらには、主術者以外の光路に配置された第2の光分割素子を介して2つの観察光路に分ける構成において、第2の光分割素子を光路から挿脱することなく夫々の観察光路を通る光量比を調整可能な手術用顕微鏡を提供する。【解決手段】観察対象3を肉眼で観察する肉眼観察光学系1と、観察対象3を撮像する撮像光学系2と、観察対象3からの光を透過及び反射することによって肉眼観察光学系1の光路を通る光と撮像光学系の光路を通る光とに分割する光分割素子4を備えた手術用顕微鏡において、撮像光学系2は、光分割素子4の透過側に配置され、光分割素子4は、可視波長帯域では一定の透過率を有し、近赤外波長帯域では可視波長帯域での透過率よりも高い透過率を有する。【選択図】図1
