Light shield device

Abstract

A method of creating a visual impairment zone includes producing at least one beam of intense light having a bandwidth of less than 50 nm. The beam of intense light is modulated to produce a spatial array having a pattern of light beams illuminating the visual impairment zone. The pattern of light beams is altered as a function of time to form a varying spatial array, wherein the varying spatial array has the requisite irradiance to cause visual impairment.

1 . A method of creating a visual impairment zone, the method comprising:
 producing at least one beam of intense light having a bandwidth of less than 50 nm;   modulating the at least one beam of intense light to produce a spatial array comprising a pattern of light beams illuminating the visual impairment zone; and   altering the pattern of light beams as a function of time to form a varying spatial array, wherein the varying spatial array has the requisite irradiance to cause visual impairment.   
     
     
         2 . The method of  claim 1 , wherein the modulating comprises splitting the at least one beam of intense light into the pattern of light beams. 
     
     
         3 . The method of  claim 1 , wherein the modulating comprises moving the at least one beam of intense light across a space in a predetermined temporal pattern. 
     
     
         4 . The method of  claim 1 , where the modulating comprises using a diffractive optical element. 
     
     
         5 . The method of  claim 1 , wherein the modulating comprises using a multiplexer, a mirror, a prism, or beam steering element, or a combination thereof. 
     
     
         6 . The method of  claim 5 , wherein the modulating further comprises using a diffractive optical element. 
     
     
         7 . The method of  claim 1 , wherein the modulating comprises using a reflective light valve, a refractive light valve, or a combination thereof. 
     
     
         8 . The method of  claim 1 , wherein the at least one beam of intense light is produced by a laser or an LED. 
     
     
         9 . The method of  claim 1 , wherein the at least one beam of intense light has a peak wavelength in a range of 400 nm to 700 nm. 
     
     
         10 . The method of  claim 1 , wherein the requisite irradiance is at least 5×10 −8  W/cm 2 . 
     
     
         11 . The method of  claim 1 , further comprising adjusting a parameter of the at least one intense beam of light to account for eye protection worn by an intruder in the visual impairment zone. 
     
     
         12 . The method of  claim 11 , wherein the parameter comprises intensity or wavelength. 
     
     
         13 . The method of  claim 1 , wherein the at least one intense beam of light comprises a luminance flicker. 
     
     
         14 . The method of  claim 13 , wherein the luminance flicker has a frequency in a range 2-25 Hz. 
     
     
         15 . The method of  claim 1 , further comprising activating a broad band light source to produce broad band light. 
     
     
         16 . The method of  claim 15 , wherein the broad band light is pulsed. 
     
     
         17 . The method of  claim 1 , further comprising:
 producing a second beam of intense light having a bandwidth of less than 50 nm and a peak wavelength that is different from a peak wavelength of the at least one beam of intense light; and   modulating the second beam of intense light so that the pattern of light beams comprises light produced from the at least one beam of intense light and light produced from the second beam of intense light.   
     
     
         18 . The device of  claim 17 , wherein the beams of intense light are selected from:
 an ultraviolet light having a peak wavelength range 310-400 nm,   a blue light having a peak wavelength range 400-500 nm,   a green light having a peak wavelength range of 500-580 nm,   a red light having a peak wavelength range 580-700 nm, or   an infrared light having a peak wavelength range 700-1500 nm.   
     
     
         19 . The method of  claim 17 , wherein the beams of intense light produce a chromatic flicker. 
     
     
         20 . The method of  claim 19 , wherein the chromatic flicker is a red/blue flicker having a frequency of less than 30 Hz.