METHOD AND APPARATUS FOR MODIFYING THE SPREAD OF A LASER BEAM

• US 20070153293A1
• Filed: 03/14/2007
• Published: 07/05/2007
• Est. Priority Date: 02/13/2003
• Status: Active Grant

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: Russell Gruhlke, William Trutna
• Inventors: Gruhlke, Russell, Trutna, William
• Granted Patent: US 7,474,680 B2
• Time in Patent Office: Days
• US Class Current: 356/511
• CPC Class Codes: G06F 3/0317 in co-operation with a patterned surface, e.g. absolute position or relative movement detection for an optical mouse or pen positioned with respect to a coded surface
• CPC Class Codes: H01S 5/005 Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping H01S5/026, H01S5/18388 take precedence
• CPC Class Codes: H01S 5/183 having only vertical cavities, e.g. vertical cavity surface-emitting lasers [VCSEL]

Abstract

An apparatus and method for modifying the spread of a laser beam. The apparatus comprises a laser source operable to generate a laser beam having a flux that exceeds a predetermined value and an optical train operable to modify the beam such that the flux of the beam through a predetermined aperture does not exceed the predetermined value. The optical train may include a focusing lens, a diffractive focusing vortex lens, a beam splitting device, or a two-dimensional diffraction grating.

Claims

1. An apparatus, comprising:

a laser source operable to generate a laser beam having a flux that exceeds a predetermined value;

an optical train operable to modify the beam such that the flux of the beam through a predetermined aperture does not exceed the predetermined value;

wherein the optical train comprises a beam splitting element operable to split the laser beam into two or more sets of beams having angle between any two sets of beams.

2. The apparatus of claim 1 wherein the beam splitting element comprises one or more prisms.

3. The laser beam modifying apparatus of claim 1 wherein the minimum angle between any two sets of rays is approximately 24.2 degrees.

4. An apparatus, comprising:

a laser source operable to generate a laser beam having a flux that exceeds a predetermined value;

an optical train operable to modify the beam such that the flux of the beam through a predetermined aperture does not exceed the predetermined value;

wherein the optical train comprises a diffraction grating operable to diffract the laser beam into two or more sets of beams having a non-zero angle between any two sets of beams.

5. The apparatus of claim 4 wherein the minimum angle between any two sets of rays is approximately 12.1 degrees.

6. The apparatus of claim 4 wherein the diffraction grating is a two-dimensional diffraction grating.