Peter J Janssen, 8827 Innsbruck Blvd, East Fishkill, NY 12533

6384817, May 7, 2002

Dec 21, 1999

09/469455

Peter J. Janssen - Scarborough NY
Lucian Remus Albu - New York City NY
John E. Dean - Stormville NY

Philips Electronics North America Corporation - New York NY

G09G 500

345204, 345 98, 345208, 345690, 345214

In an electro-optic display device, such as a liquid crystal display device which serves as a modulator for projected light, a global ramp generator is used in conjunction with track and hold circuits to convert incoming digital display signals to analog signals, and to address the individual pixels of the display device with such analog signals. A plurality of column drivers, each coupled to the ramp generator and to the pixels in a column of the display device, track and hold the ramp voltage signal when it reaches a value corresponding to the desired brightness level of a particular pixel in the respective column. At least one current source is provided, coupled to the signal source output, for supplying current to the signal source output, as needed, to compensate for switching the capacitive load of the column drivers on and off. As a result, transient voltages in the ramp signal are avoided.

6429858, Aug 6, 2002

Mar 29, 2000

09/537826

Peter J. Janssen - Scarborough NY
Lucian R. Albu - New York NY

Koninklijke Philips Electronics N.V. - Eindhoven

G09G 500

345204, 345213

In an electro-optic display device, such as a liquid crystal display device which serves as a modulator for projected light, a global DAC controlled ramp generator is used in conjunction with track and hold circuit for each column of the display to convert incoming digital display signals to analog signals for all columns. Row address circuitry addresses each row of the display, thereby to address the individual pixels of the display device with such analog signals. The limitation on an increase in frame rate, resulting from the finite conversion time (cycle time) of the DAC and the finite speed of the track and hold circuits, is overcome by providing a multi-phase clock and multiplexer which enables a selection from among several analog levels during each ramp cycle.

6462728, Oct 8, 2002

Dec 21, 1999

09/469449

Peter J. Janssen - Scarborough NY
John E. Dean - Stormville NY
Lucian Remus Albu - New York City NY

Koninklijke Philips Electronics N.V. - Eindhoven

G09G 336

345100, 345 89

In an electro-optic display device, such as a liquid crystal display device which serves as a modulator for projected light, a global DAC controlled ramp generator is used in conjunction with track and hold circuit for each column of the display to convert incoming digital display signals to analog signals for all columns. Row address circuitry addresses each row of the display, thereby to address the individual pixels of the display device with such analog signals. The limitation on an increase in frame rate, resulting from the finite conversion time (cycle time) of the DAC, is overcome by reducing the grey scale resolution, thus reducing the number of times that the DAC must convert a digital number to an analog voltage during each ramp cycle, and restoring the original resolution using temporal âditheringââi. e. , interpolation between the brightness levels of pixels in successive frames.

6466189, Oct 15, 2002

Mar 29, 2000

09/537825

Lucian R. Albu - New York NY
Peter J. Janssen - Scarborough NY

Koninklijke Philips Electronics N.V. - Eindhoven

G09G 336

345 87, 345 98

A system for generating an image in an RLCD using current sources instead of voltage sources to reduce noise and power consumption. The current is provided by a plurality of RAM-driven IDACs. Each IDAC drives one of a plurality of RLCD columns in conjunction with one of a plurality of OTAs. A Look-Up-Table in each RAM holds a plurality of 6-bit digital values that correspond to the time-derivative of the values contained in gamma correction curves. The LUT values are automatically corrected at the end of each display cycle by an auto-correction module.

6469687, Oct 22, 2002

Dec 28, 1998

09/221956

Peter Janssen - Scarborough NY

Koninklijke Philips Electronics N.V. - Eindhoven

G09G 336

345 94, 345 76, 345 89, 345204, 345208, 345 51, 348790, 348792, 348293

In driver circuitry for driving an electro-optic display device having a row and column matrix array of pixels, including means for converting incoming digital display information signals into analog signals, sampling errors due to switch and column resistance and transmission delays are compensated by converting the digital samples for alternate columns (or rows) to analog signals having sampling errors of equal magnitude but opposite sign.

6496173, Dec 17, 2002

Mar 29, 2000

09/537824

Lucian R. Albu - New York NY
Peter J. Janssen - Scarborough NY

Koninklijke Philips Electronics N.V. - Eindhoven

G09G 510

345 98, 345147

A system for generating an image in an RLCD using pulsed current sources instead of pulsed voltage sources to reduce noise and power consumption. The current is provided by a plurality of RAM-driven IDACs having a current output. Each IDAC drives one or more of a plurality of RLCD columns in conjunction with one of a plurality of OTAs. Time-integration of the applied current by the intrinsic column capacitance of the RLCD creates a controlled voltage ramp on the column capacitance. A Look-Up-Table within each RAM holds a plurality of 8-bit digital values that correspond to the time-derivative of the current values.

6533422, Mar 18, 2003

Aug 3, 2001

09/920711

Peter J. Janssen - Scarborough NY
John Alfred Domm - Kitchener, CA

Koninklijke Philips Electronics N.V. - Eindhoven

G30B 2122

353119, 353 54

An optical projection system having optical components immersed in a liquid. An enclosure holds the liquid, a spherical lens, a polarizer, a polarizing beam splitter, a reflective light valve having a retarder foil, and an exit window. The liquid stabilizes the thermal environment, reduces the need for antireflective coatings, enables a reduction in the number of optical components, and enables high optical flux.

6540362, Apr 1, 2003

Aug 9, 2000

09/635112

Peter J. Janssen - Scarborough NY

Koninklijke Philips Electronics N.V. - Eindhoven

G03B 2128

353 31, 353 20, 353 38, 353 84, 359204

Single panel scrolling color projection systems using three (red, blue and green) scrolling color stripes have been demonstrated to be adequate for television images. However, computer graphics displays are more prone to color artifacts. The invention increases the number of scrolling color stripes in order to suppress these artifacts. One implementation is to break up the three color stripes into multiple bands using a lenticular lens array, and then to collimate the multiple stripes with a second lens array. The collimated stripes are scrolled using the rotating prism of the prior systems.