TIRF condenser

The Agilent TIRF (Total Internal Reflection Fluorescence) combines the evanescent field and widefield epifluorescence illumination in a simultaneous or rapidly sequential manner.

The TIRF principle

By confining fluorescence excitation to a very thin excitation volume near a glass-water interface, where total internal reflection occurs, TIRF provides super-resolution in z-direction since fluorescently labeled structures and reporter molecules within the range of the evanescent field may be discriminated against a high background of other fluorescence outside. TIRF provides maximal signal-to-noise ratio moreover, since the extent of the evanescent field depends on both wavelength and angle of the incidence, TIRF provides user controllable penetration depth.

The novel optical design (patents pending) of the TIRF merges the two beams without sacrificing illumination efficiency and freedom of wavelength choice. This merging occurs where the beams do not overlap, i.e. at a plane conjugate to the back focal plane of the objective lens.

As an inherent laser safety measure, the beam-merging design ensures that laser light passes only at "safe positions", where total internal reflection occurs and hence no laser light can escape from the sample.

The beams are conveyed to the TIRF condenser via flexible quartz fibers. Both light paths can deliver light of different wavelengths. For widefield epifluorescence we recommend the Polychrome 5000 or Polychrome 3000 illumination unit, for laser illumination we refer you to the multicolor Laser Line Combiner.

Manufacturer	Zeiss	Olympus	Nikon
supported microscopes	Axiovert 100, 150, 200	IX series	TE 2000