Philips Lumileds Lighting Company LLC

Koninklijke Philips Corporation N.v.

U.S. Philips Corporation

Pascal J H Bloemen

Nicola Bettina Pfeffer

Kars-Michiel Hubert Lenssen

Reinder Coehoorn

Willem Hendrik Smits

Wilco Klaassens

Nicola B Pfeffer

Wiep Folkerts

Emanuel N H J Stassar

Pieter J Q Van Voorst Vader

An optical system includes a cylindrical side emitter lens, a reflector and a cylindrical Fresnel lens to produce a substantially uniformly illuminated exit plane with well collimated light in the forward direction. The cylindrical side emitter lens redirects light from a light source, such as a number of light emitting diodes placed in a straight line, into side emitted light along an optical axis that is parallel with the exit plane. The reflector may be a stepped multi-focal length reflector that includes multiple reflector surfaces with different focal lengths based on the surfaces distance to the light source and height to redirect light from the cylindrical side emitter lens to illuminate the exit plane and collimate the light along one axis in the forward direction. The cylindrical Fresnel lens is used to collimate the light along an orthogonal axis in the forward direction.

Compact optical system and lenses for producing uniform collimated light

A plurality of light emitting diode dies (LED) with associated secondary optics, which produce different light distribution patterns, are combined to produce an efficient light source having a desired illumination pattern. By way of example, a first LED may include a lens that produces a light distribution pattern with a maximum intensity at the center while a second LED may use a lens that produces a light distribution pattern with a maximum intensity that surrounds the maximum intensity of the pattern produced by the first LED. The light from the LEDs can then be combined to produce a desired illumination pattern. Additional LEDs and lenses, e.g., having different light distribution patterns may be used if desired. Moreover, a variable current driver may be used to vary the amount of current to the different LEDs, such that the combined illumination pattern may be varied as desired.

Multiple light emitting diodes with different secondary optics

Various techniques are described herein for combining two or more LEDs in a single reflective cavity for a rear lamp in an automobile. The LEDs may be two or more different colors for performing different functions, such as a stop light, a turn signal, and a tail light. In one embodiment, the LEDs have side emitting lenses and are coaxially aligned in a parabolic reflector. The LEDs may be mounted facing each other or mounted in the same direction, or a combination of both. The LEDs may share a common heat sink. A second reflector may be positioned inside a larger reflector, where a first LED is mounted near the focal point of the larger reflector, and a second LED is mounted near the focal point of the inner reflector. Additional LEDs may also be mounted in either reflector and separately controlled.

LED assembly for rear lamps in an automobile

A thin film magnetic field sensor with perpendicular axis sensitivity uses either a giant magnetoresistance material element or a spin tunnel junction element. The sensor element has ferromagnetic layers which have strongly different uniaxial anisotropies and/or a modified magnetization curve, achieved by antiferromagnetic exchange coupling with an auxiliary ferromagnetic layer. A strongly miniaturizable sensor has four spin tunnel junction elements connected to form a Wheatstone bridge. The magnetically sensitive element functions equally as well as a laminated flux concentrator, resulting in a low noise single domain configuration. The very simple design also allows easy definition of the fixed magnetization direction of a counter electrode. Very high output voltage combined with very low power is achieved.

Magnetic field sensor with perpendicular axis sensitivity, comprising a giant magnetoresistance material or a spin tunnel junction

In a method of manufacturing a multilayer film consisting of a stack of primary soft-magnetic layers and secondary non-magnetic layers on a substrate by way of reactive sputtering, use is made of one type of target at least as regards composition for alternately depositing a primary and a secondary layer, which target is particularly made of an FeHf alloy. For performing a sputtering process, use is preferably made of a gas mixture of Ar and O,in which the quantity of O,in the gas mixture is controllable and is smaller for sputtering the soft-magnetic layers than for sputtering the non-magnetic layers.

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Eindhoven, Netherlands

Pascal J H Bloemen