COAXIAL DISTANCE MEASUREMENT VIA FOLDING OF TRIANGULATION SENSOR OPTICS PATH

• US 20130256285A1
• Filed: 03/30/2012
• Published: 10/03/2013
• Est. Priority Date: 03/30/2012
• Status: Active Grant

• Current Assignee: View Incorporated
• Original Assignee: View Incorporated
• Inventors: Baxter, Bruce, Mullins, Dennis
• Granted Patent: US 10,112,258 B2
• Time in Patent Office: Days
• US Class Current: 219/121.72
• CPC Class Codes: B23K 26/048 by controlling the distance between laser head and workpiece
• CPC Class Codes: B23K 26/364 for making a groove or trench, e.g. for scribing a break initiation groove
• CPC Class Codes: G01S 17/48 Active triangulation systems, i.e. using the transmission and reflection of electromagnetic waves other than radio waves
• CPC Class Codes: G01S 7/481 Constructional features, e.g. arrangements of optical elements

Abstract

This disclosure provides apparatus and methods for scribing a substrate. In one aspect, an apparatus includes optics for focusing a scribe beam onto a substrate and a beam focus adjustment mechanism for adjusting the optics. A triangulation-based distance sensor determines a distance between the triangulation-based distance sensor and the substrate, with the triangulation-based distance sensor being positioned at a location offset from the scribe beam. Reflecting elements are positioned to reflect an incident beam from the triangulation-based distance sensor'"'"'s source to the substrate and then back to the triangulation-based distance sensor'"'"'s detector. The beam focus adjustment mechanism adjusts the optics based on the distance between the triangulation-based distance sensor and the substrate so that the scribe beam is focused at a desired position on the substrate.

Claims

1. An apparatus configured for scribing an electrochromic lite having a first side and a second side with an electrochromic device disposed on the first side, the apparatus comprising:

a scribe laser, a scribe beam from the scribe laser configured to impinge upon the electrochromic lite from the second side and to define a scribe optical path such that the scribe beam is substantially perpendicular to the second side of the electrochromic lite, the scribe beam configured to ablate the electrochromic device; and

a triangulation-based distance sensor including a triangulation laser and a detector, the triangulation-based distance sensor oriented such that a first laser beam from the triangulation laser is substantially perpendicular to the scribe optical path, is reflected from the electrochromic lite, and then detected by the detector.

2. The apparatus of claim 1, wherein the triangulation-based distance sensor is positioned on the same side of the electrochromic lite as the scribe optical path.

3. The apparatus of claim 1, wherein the first laser beam is reflected along a path substantially perpendicular to the scribe optical path prior to being detected by the detector.

4. The apparatus of claim 1, wherein the scribe laser has an output power of greater than about 500 mW for the scribe beam.

5. The apparatus of claim 1, wherein the scribe beam and the first laser beam have different wavelengths.

6. The apparatus of claim 1, wherein the triangulation-based distance sensor further includes a first mirror oriented to reflect the first laser beam from the triangulation laser that is substantially perpendicular to the scribe optical path to substantially accommodate the scribe optical path, wherein the first laser beam is reflected such that it intersects the scribe beam at a nominal focal plane, and wherein the triangulation-based distance sensor further includes a second mirror oriented to reflect the first laser beam reflected from the electrochromic lite to the detector.

7. The apparatus of claim 1, wherein the triangulation-based distance sensor is configured to determine a position of an interface of the electrochromic lite and the electrochromic device.

8. The apparatus of claim 1, further comprising:

a focus lens, wherein the focus lens is positioned such that the scribe beam impinges substantially at an interface of the electrochromic lite and the electrochromic device.

9. The apparatus of claim 8, further comprising:

a processor, wherein the triangulation-based distance sensor is configured to determine a position of the interface of the electrochromic lite and the electrochromic device, and wherein the processor is configured to position the focus lens based on the determination of the triangulation-based distance sensor.

10. The apparatus of claim 1, wherein the detector is a charge-coupled device.

11. An apparatus for scribing a nominally flat substrate, the apparatus comprising:

(a) an optics set for focusing a scribe beam onto the substrate at a scribe position to create a scribe line on the substrate when the substrate and scribe beam are moved with respect to each other;

(b) a beam focus adjustment mechanism for adjusting the optics set to cause a focal point of the scribe beam to follow contours on the substrate as the substrate moves with respect to the scribe beam during scribing;

(c) a triangulation-based distance sensor comprising (i) a detection beam source for issuing an incident beam for reflecting off the substrate and (ii) a detector for detecting the position of a reflected beam created when the incident beam reflects off the substrate, wherein the position of the reflected beam on the detector provides an indication of a distance between the triangulation-based distance sensor and the substrate, and wherein the triangulation-based distance sensor is configured such that the incident beam emanates from the detection beam source substantially orthogonal to the scribe beam; and

(d) at least one reflecting element positioned to (i) reflect the incident beam from the triangulation-based distance sensor onto the substrate at a location on or proximate to the scribe position, and (ii) reflect the reflected beam from the substrate onto the detector, such that the triangulation-based distance sensor provides the indication of a distance between the triangulation-based distance sensor and the substrate.

12. The apparatus of claim 11, further comprising logic for receiving the indication of a distance between the triangulation-based distance sensor and the substrate and for directing the beam focus adjustment mechanism to adjust the optics set to maintain the scribe beam focal point on a region of the substrate.

13. The apparatus of claim 11, further comprising a holding mechanism for substantially maintaining the substrate'"'"'s distance from the optics set during scribing.

14. The apparatus of claim 11, further comprising a first translation stage for moving the substrate in a first direction with respect to the optics set during scribing.

15. The apparatus of claim 14, further comprising a second translation stage for moving the substrate with respect to the optics set in a direction substantially orthogonal to both (i) the direction of propagation of the scribe beam and (ii) the first direction.

16. The apparatus of claim 11, wherein the optics set comprises a focusing lens.

17. The apparatus of claim 11, wherein the scribe beam is a laser beam.

18. The apparatus of claim 11, wherein the focal point has a length of not more than about 1200 micrometers along the axial direction of the scribe beam.

19. A method for scribing an electrochromic lite having a first side and a second side with an electrochromic device disposed on the first side, the method comprising:

(a) determining a position of an interface of the first side of the electrochromic lite and the electrochromic device using a triangulation-based distance sensor, the triangulation-based distance sensor oriented such that a first laser beam from a triangulation laser is substantially parallel to the first side of the electrochromic lite, is reflected from the electrochromic lite, and is detected by a detector;

(b) adjusting a focus lens such that a scribe beam emitted from a scribe laser impinges the second side of the electrochromic lite and is focused at the interface of the first side of the electrochromic lite and the electrochromic device, an appropriate focal distance determined by the position of the interface provided by the triangulation-based distance sensor; and

(c) ablating the electrochromic device from a region of the first side of the electrochromic lite with the scribe beam.

20. The method of claim 19, wherein the scribe beam has a power of greater than about 500 mW.

21. The method of claim 19, wherein the first laser beam and the scribe beam have different wavelengths.

22. The method of claim 19, wherein the scribe beam defines a scribe optical path, wherein the triangulation-based distance sensor further includes a first mirror oriented to reflect the first laser beam, that is substantially parallel to the first side of the electrochromic lite, to substantially accommodate the scribe optical path, wherein the first laser beam is reflected such that the first laser beam intersects the scribe beam at a nominal focal plane, and wherein the triangulation-based distance sensor further includes a second mirror oriented to reflect the first laser beam reflected from the electrochromic lite to the detector.

23. The method of claim 19, wherein the detector is a charge-coupled device.

24. The method of claim 19, wherein operations (a), (b), and (c) are repeated during relative movement between the electrochromic lite and the triangulation-based distance sensor.

25. The method of claim 24, wherein the relative movement between the electrochromic lite and the triangulation-based distance sensor comprises movement of the electrochromic lite while the triangulation-based distance sensor remains stationary.

26. An assembly comprising:

a triangulation laser;

a detector;

a first mirror configured to reflect a first laser beam from the triangulation laser about 90 degrees and onto a surface of a substrate, and to tilt the first laser beam at an angle relative to a line normal to the substrate; and

a second mirror configured to reflect the first laser beam, after it is reflected from the surface of the substrate, about 90 degrees and to the detector;

wherein the assembly is configured to accommodate a scribe beam from a scribe laser such that the first laser beam strikes the substrate substantially at a focal point of the scribe beam.

27. The assembly of claim 26, further including a port for allowing a focal cone of the scribe beam to pass therethrough prior to impinging on the substrate at the focal point.

28. The assembly of claim 27, wherein the first and second mirrors are positioned on either side of the port, and wherein during operation, the first laser beam straddles the focal cone except for a region proximate the focal point.

29. The assembly of claim 26, wherein the detector is a charge-coupled device.

30. The assembly of claim 26, wherein the triangulation laser and the detector are housed in a single enclosure.