Integrated white light source using a laser diode and a phosphor in a surface mount device package

Patent metadata

Field	Value
Publication number	US-10879673-B2
Application number	US-201816014010-A
Country	US
Kind code	B2
Filing date	Jun 21, 2018
Priority date	Aug 19, 2015
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

The embodiments described herein provide a device and method for an integrated white colored electromagnetic radiation source using a combination of laser diode excitation sources based on gallium and nitrogen containing materials and light emitting source based on phosphor materials. A violet, blue, or other wavelength laser diode source based on gallium and nitrogen materials may be closely integrated with phosphor materials, such as yellow phosphors, to form a compact, high-brightness, and highly-efficient, white light source. The phosphor material is provided with a plurality of scattering centers scribed on an excitation surface or inside bulk of a plate to scatter electromagnetic radiation of a laser beam from the excitation source incident on the excitation surface to enhance generation and quality of an emitted light from the phosphor material for outputting a white light emission either in reflection mode or transmission mode.

First claim

What is claimed is:

1. An integrated white light source comprising:
a laser diode device comprising a gallium and nitrogen containing material and configured as an excitation source;
a phosphor member configured as a wavelength converter and an emitter and coupled to the laser diode device;
a common support member configured to support the laser diode device and the phosphor member,
a heat sink thermally coupled to the common support member, the common support member configured to transport thermal energy from the laser diode device and phosphor member to the heat sink;
an output facet configured on the laser diode device to output a laser beam comprised of electromagnetic radiation selected from a violet and/or a blue emission with a first wavelength ranging from 400 nm to 485 nm;
a free space, between the output facet and the phosphor member with a non-guided characteristic capable of transmitting the laser beam from the laser diode device to an excitation surface of the phosphor member;
a range of angles of incidence between the laser beam and the excitation surface of the phosphor member so that on average the laser beam has an off-normal incidence to the excitation surface and a beam spot is configured for a certain geometrical size and shape;
wherein the phosphor member converts a fraction of the electromagnetic radiation from the laser beam with the first wavelength to an emitted electromagnetic radiation with a second wavelength that is longer than the first wavelength;
a plurality of scattering centers associated with the phosphor member to scatter electromagnetic radiation with the first wavelength from the laser beam incident on the phosphor member, the plurality of scattering centers comprising defective regions embedded in a non-defective bulk of the phosphor member, wherein the defective regions comprise defects located at a first depth below the excitation surface of the phosphor member non-overlapping with defects located at a second depth below the excitation surface of the phosphor member, the first depth being different from the second depth, and the defective regions and the non-defective bulk comprising phosphor of a same type with different structures;
a reflective mode characterizing the phosphor member such that the laser beam is incident on a beam spot area on the excitation surface of the phosphor member and a white light emission is outputted substantially from the same beam spot area, the white light emission being comprised of a mixture of wavelengths characterized by at least the second wavelength emitted electromagnetic radiation from the phosphor member; and
a form factor characterizing a package of the integrated white light source, the form factor having a length, a width, and a height dimension.

2. The integrated white light source of claim 1 , wherein the common support member is configured to have a submount structure to support the laser diode device in a surface mount device (SMD) package.

3. The integrated white light source of claim 1 , wherein the laser diode device is characterized by the first wavelength in blue color range of 425 to 480 nm, the second wavelength from the phosphor member comprises a yellow color range, and wherein the white light emission is comprised of the first wavelength in blue color range and the second wavelength in yellow color range.

4. The integrated white light source of claim 1 , wherein the phosphor member is comprised of a ceramic yttrium aluminum garnet (YAG) doped with Ce or a single crystal YAG doped with Ce or a powdered YAG comprising a binder material; wherein the phosphor member has an optical conversion efficiency of greater than 50 lumen per optical watt.

5. The integrated white light source of claim 1 , wherein the phosphor member is comprised of a single crystal plate or ceramic plate selected from a Lanthanum Silicon Nitride compound and Lanthanum aluminum Silicon Nitrogen Oxide compound containing Ce 3+ ions atomic concentration ranging from 0.01% to 10%.

6. The integrated white light source of claim 1 , wherein the laser diode device is characterized by a violet first wavelength; the phosphor member comprises a combination of a first phosphor characterized by a blue color second wavelength emission, and a second phosphor characterized by a yellow third wavelength emission, and wherein the white light emission is comprised of at least the second blue wavelength emission and the third yellow wavelength emission, or wherein the first phosphor is characterized by a blue second wavelength emission, the second phosphor is characterized by a green or yellow third wavelength emission, and a third phosphor is characterized by a red fourth wavelength emission, and wherein the white light emission is comprised of at least the second blue wavelength, the third green or yellow wavelength, and the fourth red wavelength.

7. The integrated white light source of claim 1 , wherein the laser diode is characterized by a blue first wavelength; the phosphor member comprises a first phosphor characterized by a green or yellow second wavelength emission, and a second phosphor characterized by a red third wavelength emission; and wherein the white light emission is comprised of at least the first blue wavelength, the second green or yellow wavelength emission, and the third red wavelength emission.

8. The integrated white light source of claim 1 , wherein the range of angles of incidence between the laser beam and the phosphor member is comprised of an incidence angle with respect to the fast-axis of the laser beam that is an off-normal angle ranging between 1 degrees and 89 degrees, and an incidence angle with respect to the slow-axis of the laser beam that is about 0 degrees.

9. The integrated white light source of claim 1 , wherein the range of angles of incidence between the laser beam and the phosphor member is comprised of an angle of incidence with respect to the fast-axis between 5 degrees and 65 degrees.

10. The integrated white light source of claim 1 , wherein the beam spot area on the excitation surface is characterized by a diameter dimension of less than 10 mm.

11. The integrated white light source of claim 1 , wherein the beam spot area on the excitation surface is characterized by an excitation power from the laser diode of greater than 0.5 W.

12. The integrated white light source of claim 1 , wherein the white light emission is comprised of at least 250 lumens.

13. The integrated white light source of claim 1 , wherein the form factor comprises selections of the height from a dimension of less than 15 mm, and the length and the width from a dimension of less than 15 mm.

14. The integrated white light source of claim 1 , wherein the defects located at the first depth have a first periodic lateral pattern, and the defects located at the second depth have a second periodic lateral pattern different from the first lateral pattern.

15. The integrated white light source of claim 1 , wherein the phosphor member comprises a single crystal bulk region and the defective regions are embedded in the single crystal bulk region.

16. The integrated white light source of claim 1 , wherein each of the defects located at the first depth and each of the defects located at the second depth have a length that extends parallel to the excitation surface and a width that extends orthogonal to the excitation surface, the length being greater than the width.

17. An integrated white light source based on a beam of laser light, comprising:
one or more laser diode devices each comprising a cavity member having a gallium and nitrog

Assignees

• Soraa Laser Diode Inc

Inventors

• Raring James W
• Rudy Paul
• Goutain Eric
• Trottier Troy
• Mclaurin Melvin
• Harrison James
• Heikman Sten
• Cantore Michael

Classifications

• H10W72/5524

  comprising aluminium [Al] · CPC title

• H10W72/552

  comprising metals or metalloids, e.g. silver · CPC title

• H10W72/5522

  comprising gold [Au] · CPC title

• H10W72/5445

  being orthogonal to a side surface of the chip, e.g. parallel arrangements · CPC title

• H10W72/5363

  the connected ends being wedge-shaped · CPC title