An ophthalmic apparatus adapted to project a waist of a beam of the light, such that a portion of the confocal region of the waist is projected onto the cornea. The source can be at least partially coherent and/or monochromatic. The source may be a laser or a laser diode. The beam can be a Gaussian beam, or a non-Gaussian beam. The apparatus can comprise a wavefront aberrometer, an axial eye length measuring apparatus or a refractometer.