折射率渐变波导的波导层通常是用扩散或交换的方法将不同原子或离子扩散或交换入波导衬底表面一薄层中而获得的,其折射率可表示为n(d,λ)=n_(?)(λ)+Δn·f(d,λ) (1)f(∞,λ)=0 (2)其中n_(?)(λ)为衬底折射率,Δn为常数,Δnf(d,λ)是扩散或交换造成的拆射率增量.严格地说只有当d→∞时,波导层的折射率才与衬底折射率相同,同时波导层的色散才与衬底色散相同.然而许多文章在涉 The waveguide layer of the graded index waveguide is usually obtained by diffusing or exchanging different atoms or ions into a thin layer on the surface of the waveguide substrate. The refractive index can be expressed as n (d, λ) = n_ (λ) + Δn · f (d, λ) (1) f (∞, λ) = 0 where n_ (λ) is the refractive index of the substrate, Δn is a constant, Δnf , λ) is the increment of the rate of detachability caused by diffusion or exchange.Strictly speaking, the refractive index of the waveguide layer is the same as the refractive index of the substrate only when d → ∞, and the dispersion of the waveguide layer is the same as that of the substrate However many articles are involved