In this paper, an electrowetting-based prism-arrays system is proposed to be non-mechanical beam deflection controller in the three-dimensional space. The system is composed of five liquid prism units arranged at equal intervals in a cross shape. The relationship between beam deflection angle, electrowetting contact angle, and liquid refractive index are derived. The influence of electrowetting saturation, liquid refractive index, and interval between adjacent prisms on the performance of prism-arrays system are simulated in COMSOL, where the length and width of each prism are set to 3mm, and the height is set to 6mm. The shape of the liquid interface in liquid prism and its deflection are analyzed. The results show that the system succeed to achieve continuous control of beam deflection within a certain range, and the beam deflection angle of this arrayed liquid prisms is from -20° to 20° when 1-chloronaphthalene oil and 1% Nacl aqueous solution with sodium benzoate are filled in the liquid prisms. The smaller interval between adjacent prisms can increase the beam control range of the system. However, the liquid prism unit has a certain size, so the interval cannot be infinitely small. As the interval is set to 9mm, the steering region of the prism-arrays system is in a conical region with an apex angle of 40°, and the vertex of the circular cone is located at the 22.05mm in the z-axis. The proposed system will promote the development of nonmechanical beam deflection technology and have a wide range of applications.
This paper introduces radial multi-sub-mirror (MSM) synthetic aperture system structure and imaging characteristics of the liquid lens based, and the MSM array for the simulate imaging and image restoration. In order to obtain the scaling invariance of MSM system imaging, the dimensionless method is used to reduce the structural parameters. Baseline statistical distribution diagram and modulation transfer function (MTF) are used to analyze the structural characteristics and intermediate frequency(IF) characteristics. The MSM optical characteristics are calculated and the raw image is simulated under different filling factors. For the reduction of the IF characteristics of the synthetic aperture system, the raw image is restored by Wiener filtering. Using the standard deviation and peak signal-to-noise ratio between the synthetic aperture imaging system and the filled aperture imaging system, these two indicators evaluate the image quality with different fill factors. A comparative analysis of the restored images yields a relationship between filling factor and image quality. Since the large number of sub-mirrors in the MSM array, resulting in a larger number of different baselines. Because the baseline corresponds to the distribution characteristics of spatial frequency, the baseline of the MSM has a large number of repeats in the IF region, so the structure has a good response of IF. The results showed that as the sub-aperture diameter increases, the imaging quality of the MSM structure becomes better. The image restoration effect enhance with the increase of the filling factor. After wiener filtering, the image quality is improved.
The optical integrated aperture imaging system arranges several small aperture optical elements according to a certain regular spatial position, and achieves common phase precision on the same focal plane by adjusting the optical path and matching the phase. It is 0.1λ precision. As a high-precision displacement adjustment device, stacked piezoelectric ceramics can realize displacement deformation in the micrometer direction in the longitudinal direction. In this paper, a piezoelectric ceramic tube is stacked and filled with a transparent liquid medium. A compact optical phase modulator is designed and the output is prepared. Using interferometer to detect phase and combined with optimized image processing technology, an optical phase detection method with an accuracy of 0.1λ is obtained, which provides a feasible reference scheme for optical synthetic aperture common phase adjustment.
This article introduced a new type of normally closed micro-valve (NCV) equipped with curved channels and trapezia-shaped valve seat, which could solve the issues of large area of dead zone, high threshold pressure and slow response speed of NCV in the current microfluidic oscillators. The new type of NCV has a three-layered structure with a top controlling layer, medium membrane layer and the bottom feedback layer. The membrane channel in the feedback layer is specifically deigned as curved to decrease the dead zone area. The valve seat is designed as a trapezoid to reduce the adhesion between the membrane and the valve seat and the threshold pressure of the NCV , and to improve the response speed of the system .The results of simulation study on COMSOL shows that this micro-valve structure reduces the NCV threshold pressure by 45% and the oscillation period of the micro-oscillator by 36%. This article conducted further simulation studies on the factors that influence the oscillation period of micro-oscillator. When enlarging inlet flow rate of micro-oscillator, lowering NCV threshold pressure and decreasing valve seat angle, the oscillation period would be reduced. Otherwise, the oscillation period will be increased.