| 摘要 |
A filter assembly of an optical system is provided to prevent the rotation of a single notch filter reliably to improve the contrast of the optical system and the reliability of color coordinates. A set frame(201) is fixed to a housing(110). A first filter(210) is positioned in the inside of set frame. A pressing unit is fixed to the set frame while pressing the first filter. A second filter(240) is set at a predetermined interval with the first filter in the outside of the set frame. A filter frame(250) is held on the set frame while pressing the second filter. The set frame is resin, and the filter frame is metal. The interval between the first filter and the second filter is thicker than half of the thickness of the set frame and thinner than four fifth of the thickness. |
