X-Ray Optics Calculator

Main Formulae

Optical properties versus material properties and wavelength

  • Linear attenuation coefficient μ
          μ = 4 π β / λ
     
  • Length of 2π phase shift L
          L = λ/ δ
     
  • Transmission through length of 2π phase shift L
          T = exp(- λ μ / δ)  = exp(- 4 π β / δ)
     
  • Length of π phase shift Lπ
          Lπ = λ/ 2δ
     
  • Transmission through length of π phase shift Lπ
          Tπ = exp(- λ μ / 2δ)  = exp(- 2 π β / δ)
     
  • Length of π/2 phase shift Lπ/2
          Lπ/2 = λ/ 4δ
     
  • Transmission through length of π/2 phase shift Lπ/2
          Tπ/2 = exp(- λ μ / 4δ)  = exp(-  π β / δ)
     
  • Effective aperture Aeff
          Aeff = (f λ δ / β)½  = (4 π f δ / μ)½
     
  • Diffraction-limited resolution for plane wave σ
          σ = 0.664 (f λ β / δ)½  = 0.664 [f λ2 μ / (4 π δ)]½
     
  • Minimal radius of curvature at parabola apex RC
          RC = 2 f δ
     
  • Tolerance on radius of curvature at parabola apex ΔRC/RC
         ΔRC/RC =  (6.4/π) (β / δ) =  (1.6/π2) λ(μ / δ)
     
  • Transmission TA through full aperture
          TA = [√(fλδ/(2β)) / A]  erf[A /  (2√(fλδ/(2πβ))]
     
  • Transmission T through effective aperture Aeff
          T = (1/√2) erf(√(π/2))  ≈ 0.65314 = 65.314%
     
  • Maximum possible gain G
          G = T Aeff / σ  ≈ δ/β  = 4 π δ / (λ μ)


Serguei Kuznetsov , IMT RAS, Chernogolovka, Russia.