Patent ID: 8030604

Claim:
A near-field detection optical component operating in transmission, characterized in that it includes at least one portion ( 11 b ) forming at least one grating ( 11 ) of diffraction microstructures ( 11 a ) succeeding one another over several periods (p), this grating ( 11 ) being capable of converting evanescent waves ( 16 ) which are established between the component and an object ( 12 ) located in the near field when it reflects or emits a radiation having a wavelength, into propagating waves ( 16 ′) by a diffraction effect during transmission, through the portion ( 11 b ) forming the grating ( 11 ) of diffraction microstructures ( 11 a ), the period (p) of the grating ( 11 ) being of the same order of magnitude as the wavelength of the radiation, wherein the optical component further includes at least one portion ( 18 ) amplifying the evanescent waves ( 16 ) before their conversion, which cooperates with the portion ( 11 b ) forming the grating ( 11 ) of diffraction microstructures ( 11 a ).