Abstract: A system, method, and method of manufacturing directed to an optical device with increased accuracy in tracking ability. The increased accuracy can be achieved by using a multiple sensor system. A second sensor is added to the optical device. The second sensor increases the probability of obtaining a high quality image. Thus, the tracking ability of the device can be performed with greater accuracy over a single sensor device. The second sensor can also perform additional functions.

Abstract: A system, method, and method of manufacturing directed to an optical device with increased accuracy in tracking ability. The increased accuracy can be achieved by using a multiple sensor system. A second sensor is added to the optical device. The second sensor increases the probability of obtaining a high quality image. Thus, the tracking ability of the device can be performed with greater accuracy over a single sensor device. The second sensor can also perform additional functions.

Abstract: A sensor for sensing movement of an encoder. At least two sensors are mounted adjacent the encoder. Each of the sensors provides an output corresponding to the amount of movement. A pair of comparators are connected to the sensors to provide two signal outputs. The comparator outputs are then provided to a digital encoding circuit which encodes the signals as a multi-bit serial value on a single output line. The bit value can be read by forcing control pulses onto the output line through an input buffer connected to the same line. The use of the single output line eliminates the extra output pin of the prior art, enabling a three pin package to be used.

Abstract: Method and apparatus for determining small variations in capacitance, typically in a capacitive touch sensing device, includes a reference signal of a first frequency and a sample signal of a second frequency. The reference and sample signals are mixed and filtered to isolate the beat frequency therebetween, which is then measured to provide an indication of the variation in the sample frequency. The measurement can then be manipulated by a microprocessor or microcontroller to provide desired control signals. The apparatus is susceptible of digital implementation and single chip implementation.