Evanescent-Wave Microscopy.

Evanescent Wave Illumination

When an electromagnetic wave (light) in a dielectric medium of index n1 is incident upon an interface of a different dielectric material of a lower optical density, n2 at an angle θ1 greater than the critical angle, θc = sin−1(n2/n1), total internal reflection (TIR) occurs. Although all of the incident energy is reflected, an electromagnetic field with exponentially decreasing intensity propaga...

Evanescent Microwave Microscopy of Porcine Skin Tissue

Imaging of dynamic secretory vesicles in living pollen tubes of Picea meyeri using evanescent wave microscopy.

Evanescent wave excitation was used to visualize individual, FM4-64-labeled secretory vesicles in an optical slice proximal to the plasma membrane of Picea meyeri pollen tubes. A standard upright microscope was modified to accommodate the optics used to direct a laser beam at a variable angle. Under evanescent wave microscopy or total internal reflection fluorescence microscopy, fluorophores lo...

Optical resolution below λ/4 using synthetic aperture microscopy and evanescent-wave illumination

Evanescent-wave illumination is applied to synthetic-aperture microscopy on a transparent solid substrate to extend the resolution limit to λ/2(n+1) (where n is the substrate refractive index) independent of the lens NA. Using a 633 nm source and a 0.4 NA lens, a resolution to 150 nm (λ/4.2) is demonstrated on a glass (n = 1.5) substrate. Further extension to ~ 74-nm resolution (λ/8.6) is proje...

Interactions of the chemotaxis signal protein CheY with bacterial flagellar motors visualized by evanescent wave microscopy

The chemotaxis signal protein CheY of enteric bacteria shuttles between transmembrane methyl-accepting chemotaxis protein (MCP) receptor complexes and flagellar basal bodies [1]. The basal body C-rings, composed of the FliM, FliG and FliN proteins, form the rotor of the flagellar motor [2]. Phosphorylated CheY binds to isolated FliM [3] and may also interact with FliG [4], but its binding to ba...