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

Patent metadata

Field	Value
Publication number	US-11973308-B2
Application number	US-202017103587-A
Country	US
Kind code	B2
Filing date	Nov 24, 2020
Priority date	Aug 19, 2015
Publication date	Apr 30, 2024
Grant date	Apr 30, 2024

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 configured 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 is configured to convert 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 configured to scatter electromagnetic radiation with the first wavelength from the laser beam incident on the phosphor member, wherein the plurality of scattering centers comprises one or more patterned surface textures on the excitation surface of the phosphor member, including a first plurality of linear stripes with steep sidewalls laid along a length of the beam spot area in a direction parallel to a projection of a fast axis of the laser beam near upper bound part of the beam spot area on the excitation surface and configured to face the laser beam near the upper bound of the beam spot area with substantially close to a normal angle of incidence;
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 plurality of scattering centers comprises defective regions embedded locally in non-defective bulk of the phosphor member, wherein the defective regions comprise one or more defects having single length extended continuously across a lateral length the phosphor member and/or having multiple discontinuous lengths extended to the same lateral dimension of the phosphor member; or one or more sets of defects located at a first depth below the excitation surface of the phosphor member overlapped with some defects located at a second depth; or one or more sets of defective regions formed in a close-loop shape surrounding the beam spot area, the close-loop shape being one selected from a circle, an ellipse, a square, a rectangle, hexagon, and other polygon.

4. The integrated white light source of claim 1 , further comprising a second plurality of linear stripes with shallower sidewalls laid along the length of the beam spot area next to the first plurality of linear stripes in the direction parallel to the projection of the fast axis of the laser beam near center part of the beam spot area and configured to face the laser beam around a center line of the beam spot area with substantially close to a normal angle of incidence.

5. The integrated white light source of claim 1 , wherein the phosphor member is configured as a photonic crystal comprising a set of voids filled with air or a dielectric material in the excitation surface periodically spaced in the direction parallel to a projection of a fast axis of the laser beam to scatter electromagnetic radiation of the laser beam with the first wavelength within the phosphor member to be converted to the emitted beam with the second wavelength that is longer than the first wavelength.

6. The integrated white light source of claim 1 , wherein the phosphor member is configured as a photonic crystal comprising a plurality of nano-scale surface textures formed into the excitation surface to create a moth eye structure for reducing average index of refraction.

7. The integrated white light source of claim 1 , wherein the phosphor member is configured as a photonic crystal attached to the excitation surface of the phosphor member, wherein the photonic crystal comprises a surface formed with a sets of defective voids or moth eye textures configured to scatter electromagnetic radiation of the laser beam with the first wavelength incident on the excitation surface of the phosphor member and convert to the emitted beam with the second wavelength that is longer than the first wavelength.

8. 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.

9. 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%.

10. 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 configured 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 is configured to convert a fraction of the electromagnetic radiation from the laser beam with the first wavelength to an emitted electromagnetic radiation with a seco

Assignees

• Kyocera Sld Laser 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