Optical Interference Device

Abstract

An optical interference device 100 is disclosed herein. In a described embodiment, the optical interference device 100 comprises a phase shifter array 108 for receiving a collimated beam of light. The phase shifter array 108 includes an array of cells 128 for producing optical light channels from respective rays of the collimated beam of light, with at least some of the optical light channels having varying phase shifts. The optical interference device 100 further includes a focusing lens 110 having a focal distance and arranged to simultaneously produce, from the optical light channels, a focused beam of light in its focal plane and an image downstream the phase shifter array 108 for detection by an optical detector 116. The optical interference device 100 also includes an optical spatial filter 112 arranged at the focal distance of the focusing lens 110 and arranged to filter the focused beam of light to produce a spatially distributed interference light pattern in zeroth order for detection by the optical detector 116. A method for producing a spatially distributed interference light pattern is also disclosed.

1 - 20 . (canceled) 
     
     
         21 . A phase shifter array according to  claim 39 , wherein the lamellar structure includes alternately raised and recessed surfaces. 
     
     
         22 . A phase shifter array according to  claim 21 , wherein the lamellar structure includes an even number of the raised and recessed surfaces. 
     
     
         23 . A phase shifter according to  claim 21 , wherein the lamellar structure includes an odd number of the raised and recessed surfaces. 
     
     
         24 . A phase shifter according to  claim 21 , wherein the alternately raised and recessed surfaces form a concentric pattern. 
     
     
         25 . (canceled) 
     
     
         26 . A phase shifter array comprising:
 a plurality of blank cells distributed throughout the phase shifter array and configured to measure a spatial intensity distribution of a light incident on the phase shifter array; and   a plurality of array sections configured to produce phase shift of the light as the light transmitted through the phase shifter array, wherein:
 each array section in the plurality of array sections is adjacent to one or more blank cells in the plurality of blank cells; 
 each array section in the plurality of array sections comprises one or more cell sections, each cell section different from the adjacent one or more black cells; 
 of a respective array section in the plurality of array sections, each cell section in the one or more cell sections comprises a plurality of cells; and 
 of a respective cell section in the one or more cell sections, each cell in the plurality of cells produces a different optical phase characteristic from its neighboring cell in the plurality of cells. 
   
     
     
         27 . The phase shifter array of  claim 26 , wherein a blank cell in the plurality of blank cells is substantially planar. 
     
     
         28 . The phase shifter array of  claim 26 , wherein the plurality of blank cells allows measurement of the spatial intensity distribution of the light without affecting a phase of the light. 
     
     
         29 . The phase shifter array of  claim 26 , wherein the spatial intensity distribution measured by the plurality of blank cells is used to compensate for non-uniform illumination. 
     
     
         30 . The phase shifter array of  claim 26 , wherein the plurality of blank cells is arranged as a grid structure across the phase shifter array, wherein the grid structure divides the phase shifter array into I×J array sections, wherein I and J each are equal to or greater than one. 
     
     
         31 . The phase shifter array of  claim 30 , wherein the grid structure comprises one or more stripes in a first direction and one or more stripes in a second direction. 
     
     
         32 . The phase shifter array of  claim 31 , wherein the first and second directions are substantially perpendicular to each other. 
     
     
         33 . The phase shifter array of  claim 26 , wherein the plurality of array sections comprises at least two array sections substantially the same as each other. 
     
     
         34 . The phase shifter array of  claim 26 , wherein of the respective array section, the one or more cell sections comprises at least two cell sections substantially the same as each other. 
     
     
         35 . The phase shifter array of  claim 26 , wherein of the respective cell section, each cell in the plurality of cells has a different depth or thickness from its neighboring cell in the plurality of cells, thereby producing the different optical phase characteristic from its neighboring cell in the plurality of cells. 
     
     
         36 . The phase shifter array of  claim 26 , wherein of the respective cell section, each cell in the plurality of cells produces a different optical phase characteristic from any other cell in the plurality of cells. 
     
     
         37 . The phase shifter array of  claim 36 , wherein of the respective cell section, each cell in the plurality of cells has a different depth or thickness from any other cell in the plurality of cells, thereby producing the different optical phase characteristic from any other cell in the plurality of cells. 
     
     
         38 . The phase shifter array of  claim 26 , wherein of the respective cell section, the plurality of cells forms a M×N array, wherein M and N each are equal to or greater than one. 
     
     
         39 . The phase shifter array of  claim 26 , wherein of the respective cell section, a cell in the plurality of cells comprises a lamellar structure. 
     
     
         40 . The phase shifter array of  claim 21 , wherein a distance between two adjacent raised surfaces is substantially the same as a distance between two adjacent recessed surfaces. 
     
     
         41 . The phase shifter array of  claim 21 , wherein a distance between two adjacent raised surfaces is different from a distance between two adjacent recessed surfaces.