Abstract: A switched capacitor digital-to-analog converter (SC-DAC) is provided. The SC-DAC of the present invention can eliminate an influence of a reference voltage source caused by a signal dependent loading at each clock cycle, so as to completely solve a harmonic distortion of an analog output signal converted by a conventional SC-DAC. In addition, when the SC-DAC of the present invention has a plurality of converting channels, since the reference voltage source is not influenced by the effect of signal dependent loading of any converting channel, so that each converting channel can be regarded to have a separate state, and thus the purpose of channel separation can be achieved.

Abstract: To automatically detect and correct flickers in a video capture device, a frame number generator receives a plurality of frames and generates frame numbers. A storage device stores brightness values of partial pixels of a frame numbered 1. An extractor extracts brightness values of partial pixels of a frame numbered N. A difference summation device computes differences of the brightness values of the partial pixels of the frames numbered 1 and numbered N and sums up the differences to generate a brightness difference summation signal. A flicker detector detects a banding value in the brightness difference summation signal. A flicker corrector uses the banding value and the frame numbers to find a fixed frequency flicker effect in the frames, and generates a flicker correction signal when the fixed frequency flicker effect in the frames is found.

Abstract: A mouse with coordinate and suspension positioning functions, which receives a directional light produced by an external illuminator. A second image sensor receives and converts the directional light into an electrical signal, and accordingly produces a directional image corresponding to the directional light. A second memory stores the directional image. When an image captured by a first image sensor cannot be focused, a processor enables the second image sensor and the second memory in order to analyze the directional image and obtain a rotating angle of the directional light for further fulfilling a coordinate positioning.

Abstract: A coordinate positioning system with in-the-air positioning function includes an illuminator and an image sensor. The illuminator produces a directional light. The image sensor receives the directional light produced by the illuminator and produces an image corresponding to the directional light to accordingly analyze the image and obtain a rotating angle corresponding to the directional light.