Abstract: Surface plasmon microscopy methods are described which comprise irradiating a sample with a beam of electromagnetic radiation, wherein at least some of the radiation is incident on the sample at an angle or angles which results in the excitation of surface plasmons in the sample, and wherein the beam of radiation comprises a longitudinal axis passing through a focus of the beam. Both radiation reradiated from the sample by one or more surface plasmons and radiation reflected from a location on the sample which does not lie on the longitudinal axis passing through the focusare received at a detector. The received reradiated radiation is then interfered with the received reflected radiation to provide information about the sample. Apparatus for performing the methods is also described.

Abstract: Surface plasmon microscopy methods are described which comprise irradiating a sample with a beam of electromagnetic radiation, wherein at least some of the radiation is incident on the sample at an angle or angles which results in the excitation of surface plasmons in the sample, and wherein the beam of radiation comprises a longitudinal axis passing through a focus of the beam. Both radiation reradiated from the sample by one or more surface plasmons and radiation reflected from a location on the sample which does not lie on the longitudinal axis passing through the focusare received at a detector. The received reradiated radiation is then interfered with the received reflected radiation to provide information about the sample. Apparatus for performing the methods is also described.

Abstract: A method and apparatus for analyzing a sample are provided. The method can include the steps of: (i) irradiating the sample with a beam of radiation in which at least some of the radiation results in the excitation of surface waves, (ii) exciting surface waves which are confined to an area having a principal dimension comparable to the wavelength of the surface waves, (iii) detecting radiation which includes radiation produced by the surface waves, and (iv) analyzing the detected radiation.

Abstract: A method and apparatus (1) for analysing a sample (1) are provided. The method comprises the steps of: (i) irradiating the sample with a beam of radiation (4) in which at least some of the radiation is incident on the sample at an angle or angles which results in the excitation of surface waves, (ii) exciting surface waves at a surface of the sample, which surface waves are confined to an area having a principal dimension which is comparable to the wavelength of the surface waves, (iii) detecting radiation which includes radiation produced by the surface waves, and (iv) analyzing the detected radiation to obtain information about the sample. The surface waves may be excited over an annulus of the sample surface, achieved by placing the sample at a position off the focal plane of the apparatus. The surface waves may be surface plasmons.