Amplitude and phase heterodyne detection device for near-field optical microscope, has acousto-optic modulator-based device that is arranged such that wavelength of progressive signal is different from wavelength of laser beam

摘要

The device (1) has a laser cavity (2) arranged for emitting a laser beam (3) with a specific wave length toward an object (10) i.e. prism, so that an evanescent wave is generated at level of the object. A microtip (11) converts the evanescent wave into a progressive signal. An optical fiber (12) is arranged for injecting the progressive signal in the cavity, so that a perturbation is generated between the signals in the cavity. An acousto-optic modulator-based device (7) is arranged such that the wavelength of the progressive signal is different from the wavelength of the beam. An independent claim is also included for a method for heterodyne detection of amplitude and phase of an evanescent wave at a level of an object.