Apparatus and system for improving depth of focus

An optical system for improving depth of focus (DOF) thereof, comprising:

• a light source for emitting a beam to be used in a machining process;
• an optical lens module for focusing the beam;
• an actuator coupled to the optical lens module,
• wherein the actuator is actuated by a driving signal for issuing a vibration frequency to the optical lens module for controlling the same to vibrate in a specific vibration frequency on an optical axis of the optical lens module, causing the focus position of the beam to vary accordingly, and thus, causing the DOF of the optical system to increase;
• and
• a control unit that is for generating the driving signal for controlling the actuator,
• wherein the optical lens module is a refractive lens module that comprises:
• a diverging lens unit coupled to the actuator for enabling the actuator, based upon the driving signal, to cause the diverging lens unit to vibrate on the optical axis of the optical lens module to increase the DOF, the beam from the light source passing through the diverging lens unit;
• and
• a condensing lens unit disposed apart from the diverging lens unit so as to be used for focusing the beam from the light source that passes through the diverging lens unit and that is then projected onto the condensing lens unit.