Koninklijke Philips Corporation N.v.

U.S. Philips Corporation

Philips Lumileds Lighting Company LLC

Gibbo Johannes Abrahamse

Hendrik Jan Eggink

Petrus H Antonis

Edwin Maria Wolterink

Youri Martynov

Armand Boudewijn Perduijn

Wilhelmus Adrianus Gerardus Timmers

Marcellus H Smulders

Johannes Willem Herman Sillevis Smitt

A backlight illumination system for illuminating a large area with light of a uniform color has a set of a pre-determined number of light emitters arranged along a straight line. The set is divided in a plurality of subsets, each subset including at least two light emitters. Each subset comprises light emitters with substantially the same light-emission color point, the respective subsets having color points different from each other. As a first step, the light emitters of the subset with a smallest number of light emitters are assigned to respective substantially equidistant positions. The light emitters of the set are assigned to the respective positions by iteratively starting with the subset with the smallest number of light emitters, assigning the light emitters of the subset to substantially equidistant positions which are not yet occupied. The backlight illumination system according to the invention has a uniform light and color distribution.

Illumination system and display device

An opto-electronic element ( ) is mounted on a substrate ( ) comprising an electric circuit ( ) with an electrically conducting layer ( ). The opto-electronic element ( ) has a body ( ) for emitting light in a pre-selected wavelength range and is provided with current conductors ( ) which contact the conducting layer ( ). According to the invention, an adhesive material ( ) is used to mount the opto-electronic element ( ) on the substrate ( ) with clearance with respect to the substrate ( ), the body ( ) contacting the substrate ( ) via the adhesive material ( ). Preferably, the adhesive material ( ) is a heat-conducting material which serves to cool the body ( ) during operation. In order to make a reliable interconnection, the geometry of the current conductors ( ) is optimized in such a way that a small tensile force (order of magnitude 1 N) is present in a weld between the current conductors ( ) and the conducting layer ( ). The tensile force ensures that the opto-electronic element ( ) is pressed into the adhesive material ( ). The small tensile force is obtained by calibrating the current conductor ( ) during a &ldquo;press&rdquo; step in the laser-welding process.

Opto-electronic element

A discharge vessel (10) closed in a gastight manner has a cavity (11) enclosing a discharge space provided with an ionizable filling. A coil (20) with a winding (21) of an electric conductor and an assembly (30) of a heat conductor (31) and one or several elongate cores (32) of soft-magnetic material are accommodated in the cavity. The cores (32) are arranged along a longitudinal axis (33) of the heat conductor (31) in one or several recesses (34) of the heat conductor which issue into a circumferential surface (36) of the assembly (30). The heat conductor (31) occupies at least half the circumference in a cross-section perpendicular to the longitudinal axis (33) of the assembly (30). The construction of the lamp according to the invention renders possible lamp operation at higher lamp powers also without the use of a heat pipe.

Electrodeless low pressure discharge lamp with improved heat transfer

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Eindhoven, Netherlands

Gibbo Johannes Abrahamse