| A novel Optical Phased Array (OPA) technology, Waveguide Optical Phased Array (WOPA) technology, is studied. WOPA will provide a high resolution, random-access and inertialess laser scanning which overcome some obstacles of prior OP As with merits of large scanning angle, high speed and low control voltage. WOPA is pinned hope on resolve bottlenecks of laser scanning imaging. Therefore, WOPA represents a novel research direction of OPA that has numerous military and civil applications including, laser scanning imaging, laser radar, laser display, optical switch and laser printer etc.The concept of WOPA is put forward. WOPA is such a kind of OPA that is composed by many Waveguide Array Electro-Optical Scanner (WAEOS). Actually, each WAEOS itself is an independent OPA.The theory of WOPA is investigated in detail. One dimension and two dimension WOPA and their characteristics are investigated theoretically by use of the method of diffraction superposition by Huygens-Fresnel principle and the method of Fourier transform of transmissivity function.A systematic electromagnetism theory of WAEOS is established. According to electrooptical effect of crystal and electromagnetism theory of slab waveguide, coupled wave equation of WAEOS is established. Based on the coupled wave equation, the model of optical field distribution in the waveguide array of WAEOS, the model of spatial radiation field (SRF) distribution and the direction factor of WAEOS are derived. It is studied in detail of the characteristics of spatial radiation field distribution, scanning characteristics of WAEOS and influence of each parameter, including the characteristics of coupled coefficient, optical field distribution in the waveguide array, the characteristics of direction factor, transform and coupled characteristics of high order TE modes and their influence on SRF of WAEOS, which contribute to the WAEOS design.Sidelobe suppression and gratinglobe suppression are two of key technologies of WOPA applications. Amplitude weighting sidelobe suppression (AWSS) and density weighting gratinglobe suppression (DWGS), which can suppress sidelobe and gratinglobe effectively, are put forward. The influence of some amplitude weighting functions such as Gauss function on sidelobe and the influence of locating function of elements on gratinglobe are studied in detail. It is found that optimal gratinglobe suppression can be obtained to reduce the infection of gratinglobe on WAEOS by increasing the distance between adjacent elements linearly.Electrical feeding theory for realization of electro-control laser scanning of WAEOS is established. A 2πelectrical feeding scheme is put forward, that depresses feeding voltage and makes it realized of low voltage feeding. Based on 2n electrical feeding scheme, two feeding systems of singlechip and FPGA are designed and developed, which can provide outputs of scanning voltage±10V by 10 channels,800Hz & 1 MHz respectively.Four waveguides WAEOS and ten waveguides WAEOS are developed. An experiment system of WAEOS is established, with which laser scanning is realized. A laser scanning result with maximum deflect angle of 13.6°on scanning voltage of 8.7V and scanning speed of 800Hz is obtained. The experiment result shows the feasibility and realizability of WAEOS. These theoretical and experiment results can be referenced in the design and application of WAEOS.The combination theory of WAEOS array of WOPA is also studied. Double density weighting (DDW) WAEOS array, Electrical feeding theory of DDW WAEOS array and setup of WOPA system are put forward. These theories contribute to the design and application of WOPA.
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