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This paper presents first hardware implementation and investigations of a new electro-optic modulator (EOM), called the Photonic Mixer Device (PMD). The PMD is a semiconductor device combining the characteristics of fast optical sensing and modulation. Arranged to a PMD-matrix it looks like a CCD-matrix but additionally provides the depth information of each image pixel using an appropriately modulated scene illumination. Besides this feature of 3D- imaging by means of time-related correlation the PMD-chip will enable on-chip 2D-image processing by means of spatial correlation. The principle of operation of the PMD, possible technologies for realization, facilities and applications will be described. This new device offers high potential for optical sensory systems due to an amazingly simple and powerful procedure of electro-optical mixing and correlation. Both CCD and CMOS are appropriate technologies. The latter will be treated in detail as a single-element Photonic Mixer Device. Here we propose several architectures--including two quadrant (2Q)-PMDs--with readout and preprocessing circuits for both, the phase resp, time-of-flight values and the pixel intensities. Arranging PMD-pixels to a PMD-line or to a PMD-matrix will provide a new generation of flexible and powerful solid-state 3D- cameras based on time-of-flight. According to the EOM- principle, the proposed 2D-mixer requires no additional optical devices, no broadband electronic amplifiers and mixers. This solid-state PMD-array offers even more unique facilities, e.g., performing high speed spatial light modulation up to the GHz range or optical CDMA- communication. The modulation characteristic of the PMD is an important aspect of this mixer. It is associated with optimizing the layout design for the PMD, which will be presented and discussed in this paper, too. PMD test chips have been realized in CMOS technology. Some simulation and first test results of the chip are also presented. The simulation results prove the operation principle of the PMD and provide us with parameters for an optimized layout design. First experimental results verified the expected operation principle of the test PMD.
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