Pixart Imaging Incorporated

Avago Technologies Ecbu IP Pte. Ltd.

Keen Hun Leong

Thomas Patrick Murphy

Sarangan Narasimhan

Kevin Rathburn

Weng Fei Wong

Siang Leong Foo

Chee Foo Lum

Gin Ghee Tan

Song Wah Ooi

Yik Foong Soo

Sai Hong Hung

Disclosed are various embodiments of methods and devices for operating a processor or host controller in a mutual capacitance sensing device. Methods and devices for sorting motion reports provided to a host controller or other processor in a mutual capacitance sensing device, reporting touch points to a host controller or other processor in a mutual capacitance sensing device, improving noise robustness and navigation performance in a mutual capacitance sensing device, determining a touch area of a user's finger on a touch panel or touchpad of a mutual capacitance sensing device, and avoiding false wakeups and minimizing power consumption in a mutual capacitance sensing device having a touch panel or touchpad are described.

Firmware methods and devices for a mutual capacitance touch sensing device

Several different methods of testing the integrity and proper operation of the drive and sense electrodes in a mutual capacitance sensing device such as a touchscreen or touchpad are disclosed herein. According to one embodiment, measured values of mutual capacitance corresponding to individual cells in a mutual capacitance sensing device are compared to one another and to predetermined thresholds. The results of the comparison are employed to determine whether any of the traces forming the electrodes in the device are defective. By way of example, traces can be defective if they are broken, too thin, too thick, or shorted together. The various embodiments of the methods disclosed herein may be used for touchscreen or touchpad quality control in a manufacturing setting, or may be used to test touchscreens or touchpads that have already been incorporated into electronic devices. The various methods disclosed herein lower manufacturing costs, increase product quality and yield, and may be carried out quickly.

Method and apparatus for detecting defective traces in a mutual capacitance touch sensing device

An optical encoder includes an optical encoder pattern of alternating light elements and dark elements, and an optical unit, including an optical emitter providing light to the encoder pattern, and an optical sensor including a photo-detector receiving the light from the optical encoder pattern and in response thereto outputting a sinusoidal signal indicating relative movement between the optical sensor and the encoder pattern. In one embodiment, the photo-detector has a diamond shape, a modified-diamond shape, or an hourglass shape. In another embodiment, at least one of the light elements and the dark elements of the optical encoder pattern has a diamond shape, a modified-diamond shape, or an hourglass shape.

Optical encoder with sinusoidal photodetector output signal

Growing community of inventors

Penang, Malaysia

Keen Hun Leong