Method for Printing a Near Field Photoinduced Stable Structure, and Optical Fiber Tip for Implementing Same

Abstract

The method comprises emitting appropriate polarisation light waves on a photosensitive material for inducing therein a topographic modification through an aperture of at the most 100 mm bound by an opaque area, said layer being arranged at the most 100 mm away from the aperture.

1 - 40 . (canceled) 
     
     
         41 . A method for producing an optical fiber useful as a near field probe, comprising:
 (a) subjecting the optical fiber to heat sequential stretching until it breaks to obtain a fiber comprising an end portion, the end portion comprising a tip with an end having the form of a truncated cone bound by a globally planar side and a circumferential surface; and   (b) subjecting the tip of the fiber to isotropic chemical etching, wherein the circumferential surface of the truncated cone is made opaque, such that the globally planar side forms an aperture with a maximum dimension of 100 nm.   
     
     
         42 . The method of  claim 41 , wherein the isotropic chemical etching of the top of the fiber is performed with an acid. 
     
     
         43 . The method of  claim 42 , wherein the acid is hydrofluoric acid HF. 
     
     
         44 . The method of  claim 41 , wherein the circumferential surface of the truncated cone is made opaque by coating it with at least one metallic layer. 
     
     
         45 . The method of  claim 44 , wherein the coating of the metallic layer occurs under vacuum, in the presence of a metallization source. 
     
     
         46 . The method of  claim 45 , wherein, during the coating, the optical fiber is oriented towards the metallization source so as to avoid metal from being coated on the globally planar side of the truncated cone. 
     
     
         47 . The method of  claim 46 , wherein, during coating, the end portion of the optical fiber is subjected to an axial rotation movement and to a rotation movement around an axis carried by the average direction of the evaporation flow. 
     
     
         48 . An optical fiber comprising an end portion having the general shape of a tip with the end having the shape of a truncated cone bound by a circumferential surface and a globally planar side defining an aperture allowing light waves to pass, the end portion capable of maintaining polarization properties of propagating light waves, wherein the globally planar side has a maximum dimension of 100 nm and the circumferential surface of the truncated cone is opaque. 
     
     
         49 . The optical fiber of  claim 48 , wherein the truncated cone has an apex angle ranging from 30 to 70°. 
     
     
         50 . The optical fiber of  claim 49 , wherein the truncated cone has an apex angle ranging from 40 to 70°.