Identification markers for light-emitting diodes and related methods
Solid-state lighting devices including light-emitting diodes (LEDs) and more particularly identification markers for LED packages and related methods are disclosed. Identification markers may include materials incorporated within LED packages that are transparent in a visible spectrum but detectable when illuminated with light outside the visible spectrum. When radiated with light outside the visible spectrum, identification markers may provide light in the visible spectrum. Alternatively, identification markers may provide light outside the visible spectrum that is detectable with equipment capable of detecting nonvisible light. Identification markers are generally configured to not be readily visible under inspection as a way to make LED packages more difficult for copying in counterfeit products.
1 . A light-emitting diode (LED) package comprising:
at least one LED chip configured to generate light in a first wavelength range from 400 nanometers (nm) to 700 nm;
a support structure comprising electrical connections electrically coupled to the at least one LED chip;
an identification marker on the support structure, the identification marker configured to be transparent to the light in the first wavelength range; and
an encapsulant on the support structure, the encapsulant covering the at least one LED chip and the identification marker on the support structure.
2 . The LED package of claim 1 , wherein the identification marker is configured to be detectable under light in a second wavelength range that is outside the first wavelength range.
3 . The LED package of claim 2 , wherein the identification marker is configured to convert light in the second wavelength range to visible light in the first wavelength range.
4 . The LED package of claim 2 , wherein the identification marker is configured to absorb light in the second wavelength range and generate light in the second wavelength range that is detectable with a detection device capable of detecting light in the second wavelength range.
5 . The LED package of claim 2 , wherein the second wavelength range is from 100 nm to less than 400 nm or from above 700 nm to 2000 nm.
6 . The LED package of claim 1 , wherein the support structure comprises a submount on which the at least one LED chip is mounted, and the identification marker is on the submount and laterally spaced from the at least one LED chip.
7 . The LED package of claim 6 , wherein the encapsulant forms a lens over the at least one LED chip, and the identification marker is outside a boundary of the lens.
8 . The LED package of claim 7 , wherein the encapsulant forms an extension that laterally extends from the boundary of the lens to a peripheral edge of the submount, and the identification marker is covered by the extension.
9 . The LED package of claim 1 , further comprising a lumiphoric material on the at least one LED chip, the lumiphoric material configured to convert at least a portion of light from the at least one LED chip to another wavelength that is in the first wavelength range.
10 . The LED package of claim 9 , wherein the lumiphoric material is further arranged to cover the identification marker on the support structure.
11 . The LED package of claim 9 , wherein the lumiphoric material is between the identification marker and the support structure.
12 . The LED package of claim 9 , wherein the identification marker comprises a distribution of particles within the lumiphoric material.
13 . The LED package of claim 1 , wherein the identification marker is on the at least one LED chip.
14 . The LED package of claim 1 , wherein the identification marker is between the at least one LED chip and the support structure.
15 . The LED package of claim 1 , wherein the identification marker forms at least one of alphanumeric characters, a bar code, or a quick-response code.
16 . The LED package of claim 1 , wherein the identification marker comprises a unique material such that the remainder of the LED package is devoid of the unique material.
17 . A method of identification for a light-emitting device, the method comprising:
providing a light-emitting diode (LED) package comprising a support structure, at least one LED chip on the support structure and configured to emit light in a first wavelength range from 400 nanometers (nm) to 700 nm, an identification marker on the support structure and configured to be transparent to light in the first wavelength range, and an encapsulant on the support structure, the encapsulant covering the at least one LED chip and the identification marker on the support structure; and
detecting the identification marker.
18 . The method of claim 17 , wherein detecting the identification marker comprises radiating the LED package with a light source, the light source providing light in a second wavelength range from 100 nm to less than 400 nm or from above 700 nm to 2000 nm.
19 . The method of claim 17 , wherein detecting the identification marker comprises destructive characterization of the LED package.
20 . A light-emitting diode (LED) package comprising:
a support structure;
at least one LED chip on a first side of the support structure and electrically coupled to electrical connections, the at least one LED chip configured to generate light in a first wavelength range from 400 nanometers (nm) to 700 nm;
an encapsulant on the support structure, the encapsulant covering the at least one LED chip on the first side of the support structure; and
an identification marker on a second side of the support structure opposite the first side, the identification marker configured to be transparent to the light in the first wavelength range.
21 . The LED package of claim 20 , further comprising a first package mounting pad and a second package mounting pad on the second side of the support structure, wherein the identification marker is between the first package mounting pad and the second package mounting pad.