Method for examining bone in vivo, comprises obtaining a laser beam modulating the laser beam to insert therein photoacoustic frequencies including optical frequencies and acoustic frequencies, the acoustic frequencies being able to give rise to acoustic waves directing the modulated beam at a bone to cause acoustic waves resulting from the beam to travel through the bone analyzing received signals from the bone including signals resulting from the acoustic waves, to determine a mineral density and a bone quality for said bone, and thus obtain in-vivo data that can be of assistance to a doctor when diagnosing osteoporosis.
