  (Abridged) In the first part of this thesis, a general methodology for
applying image deconvolution to wide-field CCD imagery. Results show that
wavelet-based deconvolution can increase limiting magnitude up to 0.6 mag and
improve limiting resolution 1 pixel with respect to original image with no
astrometric accuracy degradation.
  In the second part, a new observational technique based on CCD fast drift
scanning has been proposed for lunar occultations (LO) and speckle
interferometry. This enables all kind of professional and high-end amateur
observatories to perform such kind of observations.
  For LO, 16 new binaries up to 2mas of projected separation were detected and
stellar diameters measurements in the 7 mas regime were obtained with that CCD
and IR subarray based techniques. A new wavelet-based LO reduction pipeline was
implemented.
  For speckle, CCD fast drift scanning technique was validated with the
observation of four binary systems with well determined orbits. The results of
separation, position angle and magnitude difference are in accordance with
published measurements. A new approach for calibrating speckle transfer
function from the binary power spectrum itself has been introduced. It does not
require point source observations, which gives a more effective use of
observation time.
