Apparatus and methods for drilling holes with no taper or reverse taper

1. An apparatus for drilling holes in a material with a laser comprising:

a first steering element positioned to steer a beam from the laser;

a second steering element positioned to steer the beam from the first steering element; and

a lens for focusing the beam from the second steering element,

wherein the first and second steering elements are configured to move with respect to the beam,

moving the first and second steering elements changes an angle of the beam where it contacts the material, and

at least one of the first and second steering elements is configured to move in a sine wave motion in one of two dimensions and in a cosine wave motion in the other one of the two dimensions.

2. The apparatus of claim 1 , wherein moving the first and second steering elements further changes a position of the beam where it contacts the material.

3. The apparatus of claim 1 , wherein the first and second steering elements are scan mirrors.

4. The apparatus of claim 1 , wherein the first steering element is a glass block and the second steering element is a scan mirror.

5. The apparatus of claim 1 , further comprising:

at least one piezoelectric actuator coupled to the first steering element and configured to move the first steering element with respect to the beam in the two dimensions; and

at least one piezoelectric actuator coupled to the second steering element and configured to move the second steering element with respect to the beam in the two dimensions,

wherein the piezoelectric actuators coordinate the movement of the first and second steering elements.

6. The apparatus of claim 5 , wherein:

the at least one piezoelectric actuator coupled to the first steering element comprises a first and a second piezoelectric actuator,

the first piezoelectric actuator is configured to move the first steering element in the sine wave motion in the one of the two dimensions, and

the second piezoelectric actuator is configured to move the first steering element in the cosine wave motion in the other one of the two dimensions, and

the at least one piezoelectric actuator coupled to the second steering element comprises a third and a fourth piezoelectric actuator,

the third piezoelectric actuator is configured to move the second steering element in the sine wave motion in the one of the two dimensions, and

the fourth piezoelectric actuator is configured to move the second steering element in the cosine wave motion in the other one of the two dimensions.

7. The apparatus of claim 1 , further comprising:

a first galvanometer coupled to the first steering element and configured to move the first steering element with respect to the beam in two dimensions; and

a second galvanometer coupled to the second steering element and configured to move the second steering element with respect to the beam in two dimensions,

wherein the first and second galvanometers coordinate the movement of the first and second steering elements.

8. The apparatus of claim 1 , further comprising a beam splitting element for splitting the beam from the second steering element, and

wherein the lens is a telecentric scan lens.

9. A method for drilling holes in a material with a laser, comprising the steps of:

steering the beam with a first steering element;

steering the beam from the first steering element with a second steering element;

focusing the beam from the second steering element on the material; and

changing an angle of the beam where it contacts the material by moving the first and second steering elements relative to the beam,

wherein the moving comprises rotating at least one of the first and second steering elements relative to the beam by applying a sine wave motion to the at least one of the first and second steering elements in a first dimension and a cosine wave motion to the at least one of the first and second steering elements in a second dimension perpendicular to the first dimension.

10. The method of claim 9 , wherein the changing step comprises:

changing the angle and a position of the beam where it contacts the material by moving the first and second steering elements relative to the beam.

11. The method of claim 9 , further comprising the step of:

drilling a hole with reverse taper in the material with the laser.

12. The method of claim 9 , wherein the moving step comprises:

rotating both of the first and second steering elements relative to the beam by applying the sine wave motion to each of the first and second steering elements in the first dimension and the cosine wave motion to each of the first and second steering elements in the second dimension perpendicular.

13. The method of claim 9 , wherein the moving step comprises:

synchronously moving the first and second steering elements relative to the beam.

14. The method of claim 9 , wherein the focusing step comprises:

focusing the beam on the material with a lens, the beam focused on a point on an axis of the lens.

15. The method of claim 9 , wherein the focusing step comprises:

focusing the beam on the material with a lens, the beam focused on a point removed from the axis of the lens.

16. The method of claim 9 , wherein the steering steps comprise:

steering the beam with a first scan mirror; and

steering the beam from the first scan mirror with a second scan mirror.

17. The method of claim 9 , wherein the steering steps comprise:

steering the beam with a glass block; and

steering the beam from the glass block with a scan mirror.

18. The method of claim 9 , wherein the focusing step comprises:

splitting the beam from the second steering element with a beam splitting element; and

focusing the beam from the beam splitting element on the material with a telecentric scan lens.

19. The apparatus of claim 1 , wherein both of the first and second steering elements are configured to move in the sine wave motion in the one of two dimensions and in the cosine wave motion in the other one of the two dimensions.

20. The method of claim 9 , further comprising the step of:

drilling a hole with substantially no taper in the material with the laser.

21. An apparatus for drilling holes in a material with a laser comprising:

a first steering element positioned to steer a beam from the laser;

a second steering element positioned to steer the beam from the first steering element;

a beam splitting element for splitting the beam from the second steering element into a plurality of beams; and

a telecentric scan lens for focusing the plurality of beams from the beam splitting element,

wherein the first and second steering elements are configured to move with respect to the beam, and

moving the first and second steering elements changes an angle of the beam where it contacts the material.

22. A method for drilling holes in a material with a laser, comprising the steps of:

steering the beam with a first steering element;

steering the beam from the first steering element with a second steering element;

splitting the beam from the second steering element into a plurality of beams with a beam splitting element;

focusing the plurality of beams from the beam splitting element on the material with a telecentric scan lens; and

changing an angle of the plurality of beams where they contact the material by moving the first and second steering elements relative to the beam.