Plasmonic sensor device and method for surface plasmon resonance spectroscopy

A method for surface plasmon resonance spectroscopy using a plasmonic sensor device, wherein the plasmonic sensor device includes (a) a light source configured to generate coherent light, (b) a metallic film, (c) a detector, and (d) a micromirror that is rotatable about an axis of rotation and is arranged to guide the coherent light from the light source to one side of the metallic film from which the coherent light is reflected to the detector, an angle of incidence at which the coherent light is guided to the one side of the metallic film being variable by rotation of the micromirror about the axis of rotation, and the metallic film being at least partially covered on one side by analyte molecules, the method comprising:

• varying the angle of incidence of the coherent light on the metallic film by rotating the micromirror, wherein surface plasmons are excitable in the metallic film in a manner that depends on the angle of incidence;
• and
• measuring, by the detector, the intensity of the coherent light reflected to the detector as a function of the angle of incidence;
• wherein at least one of the following:
• the measuring of the intensity of the light includes integrating values over an active surface of the detector, and is independent of location of incidence of the light on the metallic film;
• the plasmonic sensor device further comprises linkers that are located on a side of the metallic film at which the detector is located;
• the micromirror includes a first micromirror that is rotatable about a first one of the at least one axis of rotation and a second micromirror that is rotatable about a second one of the at least one axis of rotation that is not parallel to the first axis of rotation;
• and
• (a) the micromirror includes the first micromirror, a third micromirror, and a fourth micromirror, (b) the first micromirror is arranged relative to the light source and relative to the third and fourth micromirrors so that the light from the light source impinges on the first micromirror, which is rotatable about its axis of rotation to reflect the impinging light to the third micromirror for a first range of values of the angle of incidence and to the fourth micromirror for a second range of values of the angle of incidence, (c) the third micromirror is rotatable about its axis of rotation to adjust between the values of the first range, and (d) the fourth micromirror is rotatable about its axis of rotation to adjust between values of the second range.