To provide an optical filter capable of reducing dust clinging to a light incident face and capable of reducing a mounting space.

The optical filter 1 has a filter main body 2. The filter main body 2 has a preset transmission characteristics, and is formed of a piezoelectric member. An electrode 3a is formed on one side (light incident face) of the filter body 2. The electrode 3a is disposed outside of an effective area 4 so as not to interfere with the effective area 4. A transparent electrode 3b is formed on the other side of the filter main body 2. The transparent electrode 3b has a rectangular flat shape covering the other side of the filter main body 2. An AC voltage 5 is applied to an area between the electrode 3a and the transparent electrode 3b. This vibrates the filter main body 2. Dust clinging to the surface (light incident face) of the filter main body 2 is removed by the vibration.

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