Beam width of highly-focused radially-polarized fields.
نویسندگان
چکیده
On the basis of a formal analogy with the irradiance moments, analytical definitions are proposed for the width of both the transverse and the longitudinal component of rotationally-symmetric radially-polarized fields at the focal plane of a high-focusing optical system. The beam width of the whole field is also introduced. The transverse beam size is thus associated with the overall spatial structure of the field. The beam-width definitions are applied to an illustrative example, which enables us to show that, at the focal plane, the power contained within a circle whose radius is given by the proposed beam widths represents the main part of the total power.
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ورودعنوان ژورنال:
- Optics express
دوره 18 20 شماره
صفحات -
تاریخ انتشار 2010