LED module
AssigneeKoninklijke Philips Electronics N.V.
InventorsHendrik Adrianus Van Sprang, Hendrik Johannes Boudewijn Jagt, Berno Hunsche, Thomas Diederich
Life of this patent
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Abstract
The present invention relates to a LED module which converts pump light from a LED chip (120) to light at another wavelength, which is emitted from the module. The conversion takes place in a portion of a luminescent material (124). The color purity of the LED module is enhanced by reducing any leakage of pump light using a reflector in combination with an absorber. In one embodiment, the absorber is integrated as one or several thin absorbing layers between the layers of a multi-layer reflection filter (126); this may yield an even higher reduction of pump light leakage from the module.
Claims9
A light source, comprising:
- a light emitting diode (LED) chip and a luminescent wavelength converter mounted side by side on a sub-mount, the LED chip emitting excitation light in a first wavelength range, the wavelength converter converting excitation light to converted light in a second wavelength range;
- a parabolic multi-layer reflector incorporating an absorption layer, the parabolic multi-layer reflector transmitting converted light from the luminescent wavelength converter, the incorporated absorption layer reducing the parabolic multi-layer reflector's transmission of any excitation light impinging on the parabolic multi-layer reflector at substantially oblique angles;
- and
- a separate hemispherical absorber positioned around the luminescent wavelength converter so that converted light from the luminescent wavelength converter passes through the separate hemispherical absorber at a normal angle of incidence and excitation light leaking through the parabolic multi-layer reflector passes through the separate hemispherical absorber at an oblique angle.
A light-emitting diode (LED) module comprising:
- a light emitting diode (LED) chip and a luminescent wavelength converter mounted side by side on a sub-mount;
- a pair of electrical terminals providing electrical current to the LED chip;
- a parabolic multi-layer reflector incorporating an absorption layer;
- a lens enclosing the LED chip, the luminescent wavelength converter mounted side by side on the sub-mount and the parabolic multi-layer reflector incorporating the absorption layer;
- and
- a separate hemispherical absorber positioned around the luminescent wavelength converter so that converted light from the luminescent wavelength converter passes through the separate hemispherical absorber at a normal angle of incidence and excitation light leaking through the parabolic multi-layer reflector passes through the separate hemispherical absorber at an oblique angle.
Dependencies are inferred from the claim text.