A fast acting electromagnetically operated shutter for protecting an imag system from damaging light, such as intense laser light, comprised of a plurality of vane type shutters driven by magnetically moveable linear racks transferring linear to rotary motion to the midportion of each vane to aid in overcoming inertia. The linear racks are comprised of an upper rack at one end of the shutters and a lower rack at the opposite end of the shutters wherein both upper and lower racks simultaneously move reciprocally together. The racks have gear teeth thereon that are meshed with alternate vanes from first the upper and then the lower racks to transfer opposing directional rotation to adjacent vanes. An electronic shutter control means responds to input damaging light intensity signals impinging light detecting sensor means. The electronic means has the capacity to lock onto light pulsed threats, track the frequency of the threats, and control the shutter in such a manner as to neutralize the threat or alternately to close the shutter as long as a continuous wave light threat is present.