Patent ID: 11867778
Assignee: ZHEJIANG LAB
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 5:
6. A method for testing the spatial distribution uniformity of an alkali metal atom number density of an atom magnetometer, wherein after passing through a laser beam expander, a polarizer, a diaphragm, and a beam splitting prism, laser light output by a detection light laser is split into two beams of light of the same power and shape, one beam of light enters a second beam profile camera to measure a light intensity distribution matrix I(0) of incident light, the other beam of light is received by a first beam profile camera after passing through an alkali metal atom gas chamber and an oven, a vacuum cavity, a magnetic compensation coil and a magnetic shielding system outside the alkali metal atom gas chamber to measure a light intensity matrix I(l) of emergent light, and a matrix of an atom number density n on a pixel lattice is calculated by using the following formula:, n
   =
   
    
     
      -
      ln
     
     ⁢
     
      
       I
       ⁡
       (
       l
       )
      
      
       I
       ⁡
       (
       0
       )
      
     
    
    ⋆
    
     
      Γ
      L
     
     
      2
      ⁢
      
       r
       e
      
      ⁢
      cfl
     
    
   
  
  ;
 

in the above formula: re is a classical atom radius, c is a speed of light, f is a resonance intensity, ΓL is pressure broadening, and l is a travel of light in the gas chamber;
n is written in a matrix form, n
   =
   
    [
    
     
      
       
        n
        11
       
      
      
       …
      
      
       
        n
        
         1
         ⁢
         n
        
       
      
     
     
      
       ⋮
      
      
       ⋱
      
      
       ⋮
      
     
     
      
       
        n
        
         n
         ⁢
         1
        
       
      
      
       …
      
      
       
        n
        nn
       
      
     
    
    ]
   
  
  ;
 

the distribution uniformity of n is analyzed by using a discrete coefficient method, and a calculation formula is as follows:, V
  =
  
   σ
   X
  
 

σ is a variance of the matrix n, and X is an average value of all elements of the matrix n.