US Patent 7623746 - Nanoscale coaxial optical microscope

http://www.freepatentsonline.com/7623746.html

Near-field scanning optical microscopes (NSOM) provide nanoscale metrology below the resolution limits of conventional optical micrscopes. This patent from Boston College teaches a variation of this microscope type which a carbon nanotube is used as an inner conductor probe tip. Claim 1 reads:

1. A nanoscale coaxial optical probe comprising:

a inner conductor having a top end, a bottom end, and a body;

a dielectric material engaging the inner conductor; and

an outer conductor engaging the dielectric material,

wherein the inner conductor is longer at a tip surface of the probe than the dielectric material and the outer conductor; and

wherein a diameter of the inner conductor and a diameter of the outer conductor are smaller than an optical signal wavelength.