MULTIPLE BEAM LASER SYSTEM FOR FORMING STENTS

• US 20100193484A1
• Filed: 02/03/2010
• Published: 08/05/2010
• Est. Priority Date: 02/03/2009
• Status: Active Grant

• Current Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories)
• Original Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories)
• Inventors: Von Oepen, Randolf, Chen, Li
• Granted Patent: US 8,461,478 B2
• Time in Patent Office: Days
• US Class Current: 219/121.72
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61M 25/0013 Weakening parts of a catheter tubing, e.g. by making cuts in the tube or reducing thickness of a layer at one point to adjust the flexibility
• CPC Class Codes: B23K 26/0604 by a combination of beams
• CPC Class Codes: B23K 26/0626 Energy control of the laser beam B23K26/0622 takes precedence
• CPC Class Codes: B23K 26/064 by means of optical elements, e.g. lenses, mirrors or prisms
• CPC Class Codes: B23K 26/067 Dividing the beam into multiple beams, e.g. multifocusing
• CPC Class Codes: B23K 26/324 involving non-metallic parts
• CPC Class Codes: B23K 26/36 Removing material B23K26/55, B23K26/57 take precedence
• CPC Class Codes: B23K 26/361 for deburring or mechanical trimming B23K26/351 takes precedence
• CPC Class Codes: B23K 26/362 Laser etching
• CPC Class Codes: B23K 26/38 by boring or cutting

Abstract

A system and method for precision cutting using multiple laser beams is described, The system and method includes a combination of optical components that split the output of a single laser into multiple beams, with the power, polarization status and spot size of each split beam being individually controllable, while providing a circularly polarized beam at the surface of a work piece to be cut by the laser beam. A system and method for tracking manufacture of individual stents is also provided.

Claims

1. A multiple beam laser system, comprising:

a laser capable of emitting a linearly polarized laser beam;

at least one partially transmissive and partially reflective beam splitter capable of transmitting and reflecting the laser beam at a nearly linear polarization and which introduces no polarization change to the laser beam and which is capable of dividing the laser beam emitted by the laser into two laser beams;

a half wave plate disposed in an optical path of a selected one of the laser beams, the half wave plate being capable of being rotated to alter the polarization direction the laser beam;

a polarizer disposed in the optical path of the selected laser beam for adjusting the laser power of the selected laser beam at a selected polarization direction;

an adjustable beam expander disposed in the optical path of the selected laser beam to adjust the size of the selected laser beam;

a quarter-wave plate disposed in the selected beam after the beam splitter for introducing circular polarization into the selected laser beam; and

a focusing lens for focusing the selected laser beam to a desired spot size.

2. The system of claim 1, wherein the beam expander is disposed in the optical path downstream of the polarizer.

3. The system of claim 1, wherein the beam expander is disposed in the optical path upstream of the polarizer.

4. The system of claim 1, wherein the half wave plate is disposed upstream of the polarizer.

5. The system of claim 1, wherein the quarter wave plate is disposed downstream of the polarizer.

6. The system of claim 1, further comprising:

a second polarizer disposed in the optical path of a second selected one of the laser beams; and

a second beam expander disposed in the optical path of the second selected one of the laser beams upstream from the second polarizer.

7. The system of claim 1, wherein the polarizer is disposed in the between the laser and the at least one partially transmissive and partially reflective mirror.

8. The system of claim 1, wherein a power meter is disposed in the optical path of the laser beam to measure the power of the laser beam.

9. The system of claim 1, further comprising:

an achromatic lens;

a camera configured to view the cutting process through the achromatic lens; and

a dichroic mirror for reflecting the selected laser beam and for providing an optical pathway allowing the camera to view the cutting process.

10. The system of claim 9, wherein the dichroic mirror is a long wave pass mirror.

11. A system for identifying a stent, comprising:

a laser for providing a laser beam;

a computer controlled locating fixture for moving a tube in a selected manner beneath the laser beam to cut a pattern into the tube, the pattern representing information related to the identification of a stent to be cut from the tube.

12. The system of claim 11, wherein the pattern includes a tag upon which information is etched by the laser beam.

13. The system of claim 11, wherein the pattern is a bar code.

14. A method for manufacturing stents using a multiple beam cutting process comprising:

splitting a laser beam into at least two laser beams;

cutting a stent pattern into a tube using one of the at least two laser beams;

marking the stent pattern with an identifier;

sorting a batch of stents into individual stents;

reading the identifier on an individual stent;

marking information related to the identifier on a vial; and

placing the individual stent into the marked vial.

15. The method of claim 14, further comprising:

removing remove the identifier from the stent.

16. The method of claim 15, wherein removing the identifier includes electrochemically polishing the stent to remove the identifier.

17. The method of claim 15, where removing the identifier includes cutting the identifier from the stent.

18. The method of claim 14, wherein reading the identifier on the stent includes:

digitizing the identifier; and

storing the digitized identifier in a memory in operable communication with a processor.

19. The method of claim 18, wherein marking information related to the identifier on a vial includes:

reading the digitized identifier of a stent from the memory;

associating the digitized identifier with data related to the manufacture of the stent;

marking selected data related to the manufacture of the stent on the vial.