Observation of fundamental variables of optical techniques in the nanometric range

Through the analysis of an image of a 6 mm sphere recorded using evanescent illumination and a conventional optical microscope, speckle patterns, photoelastic fringes moiré fringes and holographic patterns have been detected in the nanometric range. In this paper the formation of the photoelastic fringes and the moiré patterns will be analyzed. Due to limitation of paper length the discussion of the speckle patterns and the holographic patterns is not included. Fundamental equations are derived to explain the formation of the photoelastic and moiré patterns. Utilizing FFT procedures is possible to recover from the image spatial frequencies up to 29.5 nm. This implies a resolution of the order of 1/21 of the wavelength of light well beyond the 0.5 limit postulate by Rayleigh in the 19th century. This result confirms a conjecture of Toraldo di Francia, originator of the concept of optical super resolution and of actual procedures to achieve it. Toraldo di Francia in the late 40’s and early 50’s postulated the idea that through evanescent fields optical resolution could be increased almost continuously if enough energy is available to form an image.