Laser processing device for forming vias

A laser processing device for forming vias comprising:

• a galvo mirror module having an incidence side, a reflection side, and a scanning direction;
• a first lens being an axicon lens and located at the incidence side of the galvo mirror module;
• a second lens located between the first lens and the galvo mirror module and coaxially aligned with the first lens;
• a focusing module located at the reflection side of the galvo mirror module and having a third lens linearly slid along the scanning direction of the galvo mirror module;
• and
• a laser source configured to emit a laser beam through the first lens and the second lens to convert the laser beam into an incident ring beam;
• wherein
• the galvo mirror module is configured to reflect the incident ring beam into a reflected ring beam;
• the third lens of the focusing module is configured to covert the reflected ring beam into a Bessel-like beam;
• the galvo mirror module is configured to shift a reflection direction of the reflected ring beam to move an end of the reflected ring beam along the scanning direction of the galvo mirror module;
• and
• the third lens is slid to a corresponding position along the scanning direction of the galvo mirror module according to a relative movement of the end of the reflected ring beam.