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For the ILC physics program, the detectors will need an unprecedented jet energy resolution. For the electromagnetic calorimeter, the use of a highly granular silicon-tungsten calorimeter has been proposed. We have developed a Monolithic Active Pixel-based readout for such a calorimeter, which will have extremely fine granularity and will make use of a digital readout. The first generation chip (TPACl) implements a 168x168 array comprising 50x50 pm 2 pixels. Each pixel has an integrated charge pre-amplifier and comparator. TPACI has been manufactured in the 0.18 pm INMAPS process which includes a deep p-well. We present results of the performance of the TPACI chip together with comparison to simulations and give an outlook to the second generation chip.

A fiber optic frequency shifter capable of shifting the frequency of light traveling through the fiber has been designed, constructed, and tested. The frequency of the transmitted light is shifted by stretching and contracting the optical fiber that is wound around two piezoelectric ceramic tubes. The frequency of the light is shifted by linearly changing the path length along which the light must travel. The diameters of two piezoelectric ceramic tubes are changed when a linearly increasing electric field is applied to the tubes. A servo control system is used to correct and compensate for nonlinearity of the piezoelectric material and assembly. A frequency shift of up to 305 Hz for up to 2.5 s with a linewidth of less than 1 Hz is achieved with the present setup. This frequency shifter has been successfully applied to a laser light scattering apparatus for which heterodyne experiments are made for particle electrophoretic mobility and zeta potential measurements.