Apparatus and method for material treatment and inspection using fiber-coupled laser diode

• US 5,580,471 A
• Filed: 03/30/1994
• Issued: 12/03/1996
• Est. Priority Date: 03/30/1994
• Status: Expired due to Term

• Current Assignee: Panasonic Corporation Of North America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Technologies, Inc. (Panasonic Holdings Corporation)
• Inventors: Laferriere, Paul, Fukumoto, Akira, Tatah, Abdelkrim
• Primary Examiner(s): Walberg, Teresa J.
• Assistant Examiner(s): PELHAM, JOSEPH MOORE
• Application Number:
  US08/220,119
• Time in Patent Office: 979 Days
• Field of Search: 219/121.61, 219/121.62, 219/121.63, 219/121.76, 219/121.8, 219/121.78, 219/121.81, 350/96.18
• US Class Current: 219/121.63
• CPC Class Codes: B23K 26/032 using optical means
• CPC Class Codes: B23K 26/034 Observing the temperature of the workpiece
• CPC Class Codes: B23K 26/04 Automatically aligning, aiming or focusing the laser beam, e.g. using the back-scattered light
• CPC Class Codes: B23K 26/702 Auxiliary equipment
• CPC Class Codes: G02B 6/3636 the mechanical coupling means being grooves G02B6/3652 takes precedence
• CPC Class Codes: G02B 6/3652 the additional structures being prepositioning mounting areas, allowing only movement in one dimension, e.g. grooves, trenches or vias in the microbench surface, i.e. self aligning supporting carriers
• CPC Class Codes: G02B 6/3676 Stacked arrangement
• CPC Class Codes: G02B 6/3692 with surface micromachining involving etching, e.g. wet or dry etching steps surface micromachining involving subtractive techniques B81C1/00055
• CPC Class Codes: G02B 6/422 Active alignment, i.e. moving the elements in response to the detected degree of coupling or position of the elements G02B6/4233, G02B6/4234 take precedence
• CPC Class Codes: G02B 6/4249 comprising arrays of active devices and fibres

Abstract

Apparatus and method for the precision treatment of a material using a semiconductor diode for generating a plurality of laser light beams, optical fibers coupled to the diode for transmitting and combining the light beams, and a scanner for scanning the combined light beams onto the material to be treated. Also, channels micromachined onto a fixture are provided for supporting the fibers in optimum alignment with the diode. Also provided are a camera and a thermal image capturing system for generating optical and thermal images of the material. An image processing unit is provided for receiving and processing the image to generate and transmit control signals to a diode controller to control intensity and timing of the light beams, and to a controller of the scanner to control positioning of the scanner to deflect the laser beam over the material as desired.

Claims

1. Apparatus for precision treatment of a material, comprising:

(a) laser diode array means for generating a plurality of laser light beams;

(b) means optically coupled to said generating means for transmitting and combining said light beams;

(c) means for scanning said combined light beams onto said material;

(d) means for generating an optical image of said material;

(e) means for receiving and processing said optical image to generate control signals for said laser diode array means and said scanning means, wherein said control signals for said laser diode array means control intensity and timing of said laser light beams, and said control signals for said scanning means control positioning of said scanning means to deflect said combined light beams onto said material as desired;

(f) means for generating a thermal image of said material during and after the treatment; and

(g) means for receiving and processing said image to generate control signals for said laser diode array means and said scanning means, wherein said control signals for said laser diode array means control intensity of said laser light beams over time, and said control signals for said scanning means control positioning of said scanning means to deflect said combined light beams onto said material as desired.

2. Apparatus for precision treatment of a material as claimed in claim 1 further comprising means for supporting said material and means for controlling positioning of said supporting means.

3. Apparatus for precision treatment of a material as claimed in claim 1 further comprising micromachined means for supporting said transmitting and combining means in optimum alignment with said light generating means.

4. A fixture for use in an apparatus for precision treatment of a material having laser diode array means for generating a plurality of laser light beams and optical fibers coupled to said generating means for transmitting and combining said light beams, the fixture adapted to support said optical fibers in optimum alignment with said light generating means, said fixture comprising a substrate and at least one channel having a V-shaped cross section that is micromachined in said substrate and adapted to receive one of said optical fibers, said channel having a largest width that is smaller than an outside diameter of said optical fiber so that the fiber is supported on the top edges of the V.

5. A fixture for use in an apparatus for precision treatment of a material having laser diode array means for generating a plurality of laser light beams and optical fibers coupled to said generating means for transmitting and combining said light beams, the fixture adapted to support said optical fibers in optimum alignment with said light generating means, said fixture comprising a plurality of substrates, each substrate having at least one channel with a V-shaped cross section micromachined in said substrate, said at least one channel adapted to receive one of said optical fibers, wherein said substrates are disposed relative to one another to form 2-dimensional arrays of said channels for use in high power material processing, and wherein at least one of said substrates has at least one of said channels on two opposite surfaces thereof, said channels having a largest width that is smaller than an outside diameter of said optical fibers so that the fibers are supported on the top edges of the V.

6. A plurality of fixtures as claimed in claim 5 wherein said substrates are silicon and said channels are etched in said substrates using standard optical lithography techniques.

7. A method of precision treating a material, comprising the steps of:

(a) generating a plurality of laser light beams using a laser diode array;

(b) transmitting and combining said light beams by directing said light beams into optical fibers and bundling said fibers;

(c) scanning said combined light beams onto said material;

(d) generating an optical image of said material;

(e) using said optical image to generate control signals that control intensity of said laser light beam over time and that control said scanning of said combined light beams to deflect said combined light beams onto said material as desired;

(f) generating a thermal image of said material during and after treatment of the material; and

(g) using said thermal image to generate and transmit control signals that control intensity of said laser light beams over time and that control said scanning of said combined light beams to deflect said combined light beams onto said material as desired.

8. A method of precision treating a material as claimed in claim 7 that further comprises supporting said material on a stage and controlling the positioning of said stage, thereby optimally aligning said material in relation to said light beams.

9. A method of precision treating a material as claimed in claim 7 wherein said precision treating is soldering.

10. A method of precision treating a material as claimed in claim 7 that further comprises supporting said optical fibers for optimum alignment with said light beams in at least one channel formed in a fixture using micromachining techniques.