Koninklijke Philips Corporation N.v.

Entropic Communications, Inc.

Tpo Hong Kong Holding Limited

U.S. Philis Corporation

Philips Lighting Holding B.v.

Roel Van Woudenberg

Aalbert Stek

Jurgen Jean Louis Hoppenbrouwers

David Andrew Fish

Nijs Cornelis Van Der Vaart

Guo-Fu Zhou

Jurgen J L Hoppenbrouwers

Alan G Knapp

Christoph Gerard August Hoelen

Roy Van Dijk

Johannes H M Spruit

Petrus Johannes Bremer

Henricus Marie Peeters

Siebe Tjerk De Zwart

Bart Andre Salters

Mark Johnathan Childs

Makoto Ishii

Shigeo Mikoshiba

Petrus Maria De Greef

Peter Hubertus Franciscus Deurenberg

Tomokazu Shiga

Hermanus Johannes Borg

Jan Johannes Van Den Broek

Johannes Cornelis Norbertus Rijpers

Franciscus P M Budzelaar

Harm Albert Wierenga

Alexander Christiaan De Rijck

Ruediger Johannes Lange

Fransiscus Jacobus Vossen

Mark Bolech

Jacobus Peterus Josephus Heemskerk

Johan P W B Duchateau

Otto Leo Warmuth

Robert Tolkiehn

Hermanus Henricus Josephus Wilting

Dirk De Bruin

Christoph G A Hoelen

Gerrit J T Huijgen

Paulus A H J Huijbrechts

Ronald P Groenestein

Dirk J Van Kaathoven

The present invention relates to a method and a system of reducing motion blur in a liquid crystal cell. A basic idea of the invention is to process, in an LCD system, a luminance component (Y) of a picture frame to provide motion blur reduction, wherein overdrive is applied to the luminance component only. First, a luminance component related to a first picture frame is stored. Thereafter, a luminance component of a subsequent picture frame is acquired. To reduce motion blur in the LCD, a modified luminance component (Y') is created based on a difference between the value of the luminance component of the subsequent frame and the value of the luminance component related to the first frame. Hence, based on the value of the difference in the luminance components, and color components (U, V) of the subsequent picture frame, a drive voltage is applied to the LC cell.

Motion blur reduction for LCD video/graphics processors

In an active matrix electroluminescent display device, comprising an array of display pixels, each pixel comprises an electroluminescent display element, active matrix circuitry including at least one drive transistor for driving a current through the display element, means for determining an overall brightness level of an image to be displayed in a frame period, means for controlling the at least one drive transistor of each pixel in dependence on, (1) a respective input signal providing a drive level for the pixel, and (2) the overall brightness level. The novel arrangement is capable of controlling the pixels to limit the maximum currents drawn by the pixels, thereby limiting cross-talk effects resulting from voltage drops along row or column conductors. If an image is bright, the pixel drive levels across the image, or at least part of the image, can be reduced, so that the maximum brightness is reduced.

System and method for determining an overall brightness level of an image to be displayed in a frame period in electroluminescent display devices

The invention provides an illumination system comprising a light-emitting device which excites a first luminescent element, which forms part of the light-emitting device. The light emitted from the first luminescent element and/or the light emitted by the light-emitting device excite a second luminescent element, physically separated from the light-emitting device. By employing two luminescent elements, the first element in the light-emitting device, and the second element physically separated from the light-emitting device, such as on a cover plate, the conversion of light produced by the light-emitting device is performed at both a 'local' and a 'remote' location, respectively, and the amount of luminescent material required at the remote location may be reduced compared to the situation of the prior art where the light conversion was only performed at a remote location.

Illumination system

A driving circuit () for driving a plurality of light sources () arranged in a series configuration () is described. A controllable current source () is connected to said series arrangement of light sources. Each light source (()) is bridged by a corresponding controllable switch (()). A controller () controls the operation of the current source () to set a current level and controls the operative states of the respective switches (()) in order to individually control the light output of the corresponding light sources. The controller () is capable of individually setting the switch control signals (SL(O) for the respective switches (()). Especially, the controller () is capable of boosting the light output of one selected light source (()) while maintaining the light output of other light sources in the series arrangement (). To this end, the current level is increased while the other light sources are dimmed.

Driving circuit for driving a plurality of light sources arranged in a series configuration

Disclosed is a driver that includes a main power supply that has outputs coupled across a string of light emitting diodes to supply a main current. A secondary power supply is coupled to a junction between successive light emitting diodes in the string to supply or withdraw a delta current from the junction. The delta current is at least five times smaller than the main current. A controller controls the secondary power supply to generate the delta current to obtain a desired spectral composition of the mixed light emitted by the string.

Driving light emitting diodes

The present invention relates to a method for determining drive values for driving a lighting device at a desired brightness and color. The method comprising the steps of determining a first luminous flux weight ratio based on the desired color and a first drive current for driving each of the differently colored LEDs, determining a first luminous flux for each of the differently colored LEDs based on the desired brightness and the first luminous flux weight ratio, comparing, for each of the differently colored LEDs, the first luminous flux with a nominal luminous flux for a plurality of different drive currents, selecting, for each of the differently colored LEDs, a preferred drive current that at least can produce the first luminous flux, determining a second luminous flux weight ratio based on the desired color and the selected drive currents for each of the differently colored LEDs, determining a second luminous flux for each of the differently colored LEDs based on the desired brightness and the second luminous flux weight ratio, and determining a duty cycle for each of the differently colored LEDs at the selected drive currents, wherein the selected currents at the determined duty cycles produces the second luminous flux for each of the differently colored LEDs. The present invention provides for the possibility to limit the number of necessary computational steps for determining preferred drive currents. Furthermore, an increase in number of current level and/or differently colored LEDs would only slightly increase the computational cost.

Method and driver for determining drive values for driving a lighting device

In an active matrix electroluminescent display device, an overall brightness level of an image to be displayed in a frame period is determined. A drive transistor of each pixel is controlled in dependence on an input drive signal for the pixel and on the overall brightness level, for example using a signal processor () to vary the pixel drive signals. This arrangement can control the pixels to limit the maximum currents drawn by the pixels, thereby limiting the cross talk effects resulting from voltage drops along row or column conductors. If an image is bright, the pixel drive levels across the image (or at least a part of the image) can be reduced, so that the maximum brightness is reduced.

Control of current supplied by a transistor to a pixel in an electroluminescent display device

A color electroluminescent, EL, display device comprising an array of pixels () each comprising sub-pixels () of two or more colors (R, G, B). For at least one of the colors (R, G, B), the pixel () comprises a first sub-pixel (R, G, B) comprising a first EL material and a second sub-pixel (R, G, B) comprising a second EL material. The first EL material is of higher lifetime than the second EL material; the second EL material has better color points and/or better color rendition properties than the first EL material. In some embodiments a pixel comprises two red sub-pixels (R, R), two green subpixels (G, G) and two blue sub-pixels (BL, Bc), one sub-pixel of each color (R, G, B) comprising relatively high lifetime EL material and the other sub pixel of each color (R, G, B) comprising relatively good color points EL material. In other embodiments a pixel comprises two blue sub-pixels (B, B) but only one red sub-pixel and one green sub-pixel.

Colour electroluminescent display device and its driving method

An active matrix display comprises a select driver (SD) to drive select electrodes (SE), and a data driver (DD) to supply data (D) to data electrodes (DE). Pixels () are associated with intersections of the data electrodes (DE) and the select electrodes (SE). The pixels () comprise a light emitting element (L) and a pixel driving circuit (PD). The pixel driving circuit (PD) receives a power supply voltage (VB) via a power supply electrode (PE), and data (D) via a data electrode (DE) to control a brightness of the light emitting element (L). A power supply (PS) supplies the power supply voltage (VB). The power supply electrodes (PE) are arranged to supply the power supply voltage (VB) to the pixel driving circuits (PD) of lines of pixels () extending in the same direction as the select electrodes (SE) or in the same direction as the data electrodes (DE). The load (AL; MA; IL) on the power supply electrodes (PE) caused by the pixels () associated with the lines of pixels () is determined (LL), and the level of the power supply voltage (VB) is controlled (CO) dependent on the load (AL; MA; IL).

Active matrix display with reduction of power consumption

A system for generating an audible message to a human includes an apparatus having an input for receiving an audio message. The audio message is stored in a memory. An output may be used for rendering the audio message. The apparatus further includes a microphone and a controller. If a sound is received via the microphone, the controller causes the stored audio message to be rendered via the output.

Monitoring system capable of generating audible messages

A display device () of the matrix type is addressed using partial line doubling, i.e. a method in which one or more sub-fields for pixels are doubled, meaning that the same data is used for a set of pixels. Adjacent pixels in a row are addressed using different grey level realizations by applying different combinations of subfields. Partial line doubling is performed on sets of adjacent pixels in a column that are addressed using the same grey level realization. Two different addressing schemes may be used by applying either the standard pattern A/B or the second pattern (n&#xd7;1 A/B). When applying the latter pattern partial line doubling is performed in a line skipping fashion.

Partial line doubling driving method and display device using the same

The optical data storage medium () has a substrate () with a surface area having tracks () of marks representing stored information. The information is readable by means of a scanning radiation beam (). A reflective layer () is present, reflecting the radiation beam (). The medium has a radiation beam () reflection larger than 50%. The reflective layer () comprises a compound of the formula Al,X, in which formula Al is aluminum and X is an element selected from the group of Ge and Si. The letter y is the atomic fraction of X in at. %. The value of y is in the range 5&#x3c;y&#x3c;35. The reflective layer () has a radiation beam absorption, which enables controlled ablative recording or solid-phase change recording of an identification mark (').

Optical data storage medium and use of such a medium

A multi-layer record carrier and method of manufacturing thereof and recording thereon, includes data written in units of blocks on tracks of at least two information layers. A first guard field is written at the start of a data block and a second guard field is written at the end of the data block. The power in the focused spot in the deepest of the at least two information layers is maintained substantially at an optimal value, by setting the length of the first and second guard fields such that the end position of the second guard field of a preceding data block is located within the area of the first guard field of the succeeding data block. Thereby, gap portions between the first and second guard fields can be prevented. Alternatively, the length of the first and second guard fields is set to be approximately equal to the sum of half the diameter of a recording beam in the upper one of the at least two information layers when focused on the lowest one of the at least two information layers and a maximum allowed misalignment between the two layers. Thereby, the area through which the beam passes in the information layer is of a uniform nature, when user data is being read or written. The at least two information layers are aligned by optically measuring and aligning alignment marks, such as header spokes, at predetermined measuring points.

Multi-layer record carrier and method of manufacturing thereof and recording thereon, with reduced transmission differences in the upper layer

The invention provides for a method and display apparatus () having driving circuitry for driving a display panel () having a plurality of addressable discharge cells () driven by display pulses (DP), including the steps of applying data pulses (DAP) during the time interval between display pulses (DP) and characterized by the step of priming charges for each of the discharge cells () by means of the reset discharges so as to reduce the required data voltage, and in particular such a method wherein one TV-field period (T) is divided into a plurality of sub-fields (SF) all of which are of substantially equal time durations.

Method and apparatus for driving a display panel

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Eindhoven, Netherlands

Roel Van Woudenberg