Patent ID: 8300326

Claim:
A miniaturized optical head provided to equip the distal end of a bundle of flexible optical fibres scanned by a laser beam, said optical head being configured to come into contact with a sample and to excite said sample in a confocal manner the optical head comprising: means for correcting spherical aberrations; and focusing means, wherein the focusing means comprises at least a first strongly convergent lens combined with a spherical or hemispherical lens arranged at the distal end of the optical head, and means for correcting axial and lateral chromatism that are provided with a single divergent lens the curvature of which is substantially centered on the pupil of the bundle of optical fibres and arranged at the correct distance from this pupil for which the lateral achromatization conditions coincide with the axial achromatization conditions, the divergent lens being combined with a second convergent lens in the form of a doublet, wherein the means for correcting spherical aberrations comprise a third convergent lens, the thicknesses of the first and third convergent lenses being determined so as to correct the cumulative spherical aberration on the convergent diopters, and wherein the thickness of the third convergent lens is also determined so as to image the pupil on the second convergent lens.