The present invention relates to the field of instruments for imaging internal structures of the human body, and in particular of the eye. More specifically it relates to an optimized process and an optical coherence tomography system thereof to measure the distances between the eye interfaces that is, the corneal surfaces, the surfaces of the crystalline lens, the retina and so on. A tiltable selection means, e.g. a titable mirror, is used to switch between different optical sample paths having different lengths, such that information relative to portions of the sample at different depths can be collected.
