Koninklijke Philips Corporation N.v.

Philips Lumileds Lighting Company LLC

Signify Holding B.v.

Philips Lumileds Lighting Company (Holding) B.v.

Willem Hendrik Smits

Frans Hubert Konijn

Gerard Harbers

Paul Scott Martin

Grigoriy Basin

Robert Scott West

Robert F M Hendriks

Nicola Bettina Pfeffer

Erno Fancsali

Pascal Jean Henri Bloemen

Serge Joel Armand Bierhuizen

Gerardus Johannes Josephus Vanlier

Pascal J H Bloemen

Wiep Folkerts

A light bulb includes a light emitting device at the base of the bulb and a light guide () that guides the emitted light to a diffusion element () above the base of the bulb. The diffusion element is configured to diffuse the light so as to emulate the predominantly radial light distribution pattern produced by a candle. A variety of features for the diffusion element, as well as features of the base and bulb, are presented that enhance the candle-like effects.

Candle light LED light bulbs

One or more LED dice are mounted on a support structure. The support structure may be a submount with the LED dice already electrically connected to leads on the submount. A mold has indentations in it corresponding to the positions of the LED dice on the support structure. The indentations are filled with a liquid optically transparent material, such as silicone, which when cured forms a lens material. The shape of the indentations will be the shape of the lens. The mold and the LED dice/support structure are brought together so that each LED die resides within the liquid silicone in an associated indentation. The mold is then heated to cure (harden) the silicone. The mold and the support structure are then separated, leaving a complete silicone lens over each LED die. This over molding process may be repeated with different molds to create concentric shells of lenses. Each concentric lens may have a different property, such as containing a phosphor, providing a special radiation pattern, having a different hardness value, or curable by a different technique (e.g., UV vs. heat).

Lens compression molded over LED die

The invention relates to a light emitting device () comprising a primary light source (), a light converting medium () and an optical structure (). The primary light source is disposed on a substrate (). The light converting medium comprising phosphors () is arranged for converting at least a part of the primary light to secondary light (II) of a different wavelength. The light converting medium is in a remote phosphor configuration. The optical structure is arranged for receiving a part of the secondary light (II) from the light converting medium and is configured for redirecting the part of the secondary light in a direction towards the first plane but away for the primary light source (). By providing an optical structure redirecting the secondary light away from the primary light source, absorption of the secondary light by the primary light source can be substantially reduced or eliminated. The luminous efficacy is improved by redirecting this secondary light in a direction such that it is transmitted from the light emitting device.

Efficient light emitting device and method for manufacturing such a device

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

Lenses and certain fabrication techniques are described. A wide-emitting lens refracts light emitted by an LED die to cause a peak intensity to occur within 50-80 degrees off the center axis and an intensity along the center axis to be between 5% and 33% of the peak intensity. The lens is particularly useful in a LCD backlighting application. In one embodiment, the lens is affixed to the backplane on which the LED die is mounted and surrounds the LED die. The lens has a hollow portion that forms an air gap between the LED die and the lens, where the light is bent towards the sides both at the air gap interface and the outer lens surface interface. The lens may be a secondary lens surrounding an interior lens molded directly over the LED die.

Wide emitting lens for LED useful for backlighting

Overmolded lens over LED die

A projection system is provided with a square-wave current light source and a color wheel with differently colored segments. The lifetime of the light source is long since the square-wave current constantly changes polarity a constant power is supplied to the light source and, before changing polarity, a current pulse is each time provided, driving the square-wave current to a predetermined strength which is larger than the current strength in between the current pulses. In the course of time, the amount of power in the current pulses increases relative to the amount of power in the current in between the current pulses. By controlling the timing of occurrence of the current pulses to constantly coincide in time and, on average, an equal number of times with all colors of the color wheel, the position of the white color point is independent of the period of time of use of the light source.

Projection system and method of controlling a square-wave current light source in a projection system

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Veldhoven, Netherlands

Willem Hendrik Smits