Patents by Inventor Stephen Wai-Yan Lai
Stephen Wai-Yan Lai has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 8471501Abstract: An illumination brightness control apparatus receives an input voltage from a light dimmer and produces a control signal to regulate a drive signal to a power conversion switch of a switching mode power converter. The apparatus includes a voltage conditioning circuit to condition the dimmer input voltage to provide a conditioned voltage signal; an ADC circuit to sample analog data of the conditioned voltage signal at a sampling rate that is high relative to a nominal variation rate of the dimmer input voltage and to provide digital data corresponding to the sampled analog data; a digital signal processing circuit to produce a running data average of the digital data; and a controller to produce a signal corresponding to the running data average as the control signal to regulate the drive signal.Type: GrantFiled: February 22, 2011Date of Patent: June 25, 2013Assignee: Solomon Systech LimitedInventors: Wing Chi Stephen Chan, Hing Mo Jeff Lam, Jun Pan, Stephen Wai-Yan Lai, Xiaolong He, Wai Kin Josh Cheng
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Publication number: 20120212145Abstract: An illumination brightness control apparatus receives an input voltage from a light dimmer and produces a control signal to regulate a drive signal to a power conversion switch of a switching mode power converter. The apparatus includes a voltage conditioning circuit to condition the dimmer input voltage to provide a conditioned voltage signal; an ADC circuit to sample analog data of the conditioned voltage signal at a sampling rate that is high relative to a nominal variation rate of the dimmer input voltage and to provide digital data corresponding to the sampled analog data; a digital signal processing circuit to produce a running data average of the digital data; and a controller to produce a signal corresponding to the running data average as the control signal to regulate the drive signal.Type: ApplicationFiled: February 22, 2011Publication date: August 23, 2012Inventors: Wing Chi Stephen CHAN, Hing Mo Jeff Lam, Jun Pan, Stephen Wai-Yan Lai, Xiaolong He, Wai Kin Josh Cheng
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Patent number: 8103120Abstract: Methods and apparatuses of contrast enhancement on an image are disclosed. The method performs local shading of fine contrast variations in an image, with particular advantage in tone mapping applications. The amounts of shading are determined by the preferred degree of increased image contrast 810, including compensation for subsequent tone mapping, and the difference between a profile signal 803 and the image signal 801 conditional on the signal profile level being higher than the original image signal level, wherein avoiding boosting of brightness level to obtain contrast enhancement. The profile signal 803 is calculated by the weighted sum of the image signal and the absolute signal variation which is the absolute value of the variation between the brightness of two neighbor pixels. This amount of shading is reduced to zero when the profile signal 803 is lower than the original image signal 801 for avoiding the overshooting problem at sharp edges in an image.Type: GrantFiled: September 22, 2008Date of Patent: January 24, 2012Assignee: Solomon Systech LimitedInventors: Wai Pak Choi, Stephen Wai-Yan Lai, Wing Chi Stephen Chan
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Patent number: 7791575Abstract: A driving circuit for driving a display panel including a plurality of pixels. The driving circuit includes a selecting signal generator to generate a plurality of selecting signals according to a first and a second pixel data, a voltage divider to provide a plurality of sub-transition voltages, and a voltage selector coupled to receive the plurality of sub-transition voltages and the selecting signal, and to selectively output a plurality of sub-transition voltages serially according to the selecting signals. A drive buffer is coupled to receive the outputted sub-transition voltages serially and to serially generate a plurality of sub-transition driving voltages according to the outputted sub-transition voltages during a transition time period.Type: GrantFiled: July 15, 2005Date of Patent: September 7, 2010Assignee: Solomon Systech LimitedInventors: Yuen Pat Lau, Wai Hon Ng, Stephen Wai-Yan Lai
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Publication number: 20100074553Abstract: Methods and apparatuses of contrast enhancement on an image are disclosed. The method performs local shading of fine contrast variations in an image, with particular advantage in tone mapping applications. The amounts of shading are determined by the preferred degree of increased image contrast 810, including compensation for subsequent tone mapping, and the difference between a profile signal 803 and the image signal 801 conditional on the signal profile level being higher than the original image signal level, wherein avoiding boosting of brightness level to obtain contrast enhancement. The profile signal 803 is calculated by the weighted sum of the image signal and the absolute signal variation which is the absolute value of the variation between the brightness of two neighbor pixels. This amount of shading is reduced to zero when the profile signal 803 is lower than the original image signal 801 for avoiding the overshooting problem at sharp edges in an image.Type: ApplicationFiled: September 22, 2008Publication date: March 25, 2010Applicant: Solomon Systech LimitedInventors: Wai Pak CHOI, Wing Chi CHAN, Stephen Wai-Yan LAI
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Publication number: 20090251391Abstract: A power recycling method and apparatus for driving capacitive display elements are described. The driving process involves charging and discharging the display elements. More particularly, the method effectively reuses some of the energy during the discharging process. Energy in display elements flows back from the panel to a power supply and other optionally to devices like RAM, MCU directly during the discharging process. Diodes between one or more power supplies and the display elements ensure that the discharge paths are disconnected when the voltage of display elements drops below the voltage of the power supply. A resistor path from the display elements to ground or a power supply lower than the display threshold voltage of the display elements guarantees that elements are turned OFF after the discharge process.Type: ApplicationFiled: April 2, 2008Publication date: October 8, 2009Applicant: Solomon Systech LimitedInventors: Ricky Chung Yee Ng, Felix Wai Yu Wong, Kenneth Chi Wai Lee, Stephen Wai-Yan Lai, Johnkid Lo
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Patent number: 7400098Abstract: According to the present invention, a display driver includes a voltage and current source that drive pixels and compensate for parasitic voltage to produce row pixels having intensities that are relatively uncorrelated to the number of “ON” pixels in a given row. The voltage source that provides the pre-charge for each pixel includes a constant value and a compensation voltage determined based on the number of “ON” pixels in each row. The compensation voltage is also determined based on the characteristics of the diodes associated with each pixel and the resistance associated the common ground of each row.Type: GrantFiled: December 30, 2003Date of Patent: July 15, 2008Assignee: Solomon Systech LimitedInventors: Chung Yee Ricky Ng, Stephen Wai-Yan Lai, Wai Yu Felix Wong, Cheung Fai Lee
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Patent number: 7239117Abstract: A DC-DC converter circuit includes an inductor having an inductor current, an inductor current emulation circuit for producing an emulated inductor current, and a control circuit coupled with the emulation circuit for receiving the emulated inductor current and determining a peak inductor current for the DC-DC converter.Type: GrantFiled: January 6, 2005Date of Patent: July 3, 2007Assignee: Solomon Systech LimitedInventors: Cheung Fai Lee, Stephen Wai-Yan Lai, Alvin Chit-Sang Chan, David Chin-Tung Or