US Patent 11686560 Light shield device

A visual impairment device includes a power supply, an intense light source having two or more beams of intense light with different peak wavelengths and a wavelength bandwidth less than 50 nm, a modulator and a control circuit. The modulator operates to modulates the two or more beams of intense light to produce a spatial array such that at least one of the beams used to produce the spatial array has the requisite irradiance to cause visual impairment. In some examples, the beams of intense light are laser beams. Also included are methods of using the device to cause visual impairment of an intruder who enters a visual impairment zone created by said device.