| 摘要 |
An interface between a surface of a micro optical component, and a second medium of different refractive index can be made substantially non-reflective, thereby eliminating Fresnel reflection losses for a predetermined wavelength at its surfaces, by including micro voids within the component surface. The volume fraction of voids required to eliminate the Fresnel reflection losses, v1, is: v1=[n2-(nmn2)+E,fra 1/2+EE ]/[n2-n1], where n1 is the refractive index of the void, nm is the refractive index of the medium surrounding the fiber tip, n2 is the refractive index of the optical component material, and v2 is its volume fraction in the modified surface section. The thickness, t, of the layer of lower refractive index material required at the component surface is 2N t cos theta = lambda o/2, where lambda o is the predetermined wavelength for total cancellation by interference, theta is the angle of incidence, and N=(nmn2)+E,fra 1/2+EE , where n2, is the refractive index of the component material and nm is the refractive index of the medium in contact with the component surface. At least one dimension of the micro void in the surface plane interfacing the second medium must be not greater than half the predetermined wavelength.
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