Method and apparatus using laser pulses to make an array of microcavity holes

Apparatus for forming an array of microcavities on a workpiece having a surface, the apparatus comprising:

• laser which produces a beam of laser light pulses;
• beam dividing means for dividing the beam of laser light pulses into multiple beams;
• and
• a lens system that magnifies the multiple beams by a magnification factor that is less than 1 and focuses the multiple beams onto the surface of the workpiece to cause material to be removed from the workpiece forming the microcavity array, the lens system including;
• a first lens having a front focal plane and a back focal plane, the first lens being positioned such that the beam dividing apparatus provides an image of the divided beam at the front focal plane of the first lens;
• and
• a second lens having a front focal plane and a back focal plane, the second lens being positioned such that the surface of the workpiece is at the back focal plane of the second lens.

Apparatus for forming an array of microcavities on a workpiece having a surface, the apparatus comprising:

• a laser which produces a beam of laser light pulses;
• beam dividing means for dividing the beam of laser light pulses into multiple beams, each of the multiple beams having a diameter;
• and
• a lens system that focuses the multiple beams onto the surface of the workpiece, reducing the diameter of each beam of the multiple beams to cause material to be removed from the workpiece forming the microcavity array.

Apparatus for forming an array of microcavities on a workpiece having a surface, the apparatus comprising:

• a laser which produces a beam of laser light pulses;
• beam dividing means for dividing the beam of laser light pulses into multiple beams, each of the multiple beams having a diameter;
• and
• a lens system that focuses the multiple beams onto the surface of the workpiece, reducing the diameter of each beam of the multiple beams to cause material to be removed from the workpiece forming the microcavity array, the lens system including;
• a first lens having a front focal plane and a back focal plane, the first lens being positioned such that the beam dividing apparatus provides an image of the divided beam at the front focal plane of the first lens;
• and
• a second lens each having a front focal plane and a back focal plane;
• the second lens being positioned such that the surface of the workpiece is at the back focal plane of the second lens.

Apparatus for forming an array of microcavities on a workpiece having a surface, the apparatus comprising:

• a laser which produces a beam of laser light pulses;
• an opaque mask having a pattern of openings with a hexagonal outline for dividing the beam of laser light pulses into multiple beams;
• and
• a lens system that magnifies the multiple beams by a magnification factor that is less than 1 and focuses the multiple beams onto the surface of the workpiece to cause material to be removed from the workpiece forming the microcavity array.

Apparatus for forming an array of microcavities on a workpiece having a surface, the apparatus comprising:

• laser which produces a beam of laser light pulses;
• a diffractive optical element for dividing the beam of laser light pulses into multiple beams;
• and
• a lens system that magnifies the multiple beams by a magnification factor that is less than 1 and focuses the multiple beams onto the surface of the workpiece to cause material to be removed from the workpiece forming the microcavity array.

Apparatus for forming an array of microcavities on a workpiece having a surface, the apparatus comprising:

• a laser which produces a beam of laser light pulses;
• a diffractive optical element for dividing the beam of laser light pulses into multiple beams, each of the multiple beams having a diameter;
• and
• a lens system that focuses the multiple beams onto the surface of the workpiece, reducing the diameter of each beam of the multiple beams to cause material to be removed from the workpiece forming the microcavity array.