This paper deals with vacuum UV optical coatings for micro mirror applications. High reflecting low-stress optical coatings have been developed for the next-generation of micro mechanical mirrors. The optimized metal ...This paper deals with vacuum UV optical coatings for micro mirror applications. High reflecting low-stress optical coatings have been developed for the next-generation of micro mechanical mirrors. The optimized metal systems are applicable in the VUV spectral region and can be integrated in the technology of MOEMS, such as spatial light modulators (SLM) and micro scanning mirrors.展开更多
Dynamic infrared scene simulation is for discovering and solving the problems encountered in designing, developing and manufacturing infrared imaging guidance weapons. The infrared scene simulation is explored by usin...Dynamic infrared scene simulation is for discovering and solving the problems encountered in designing, developing and manufacturing infrared imaging guidance weapons. The infrared scene simulation is explored by using the digital grayscale modulation method. The infrared image modulation model of a digital micro-mirror device （DMD） is established and then the infrared scene simulator prototype which is based on DMD grayscale modulation is developed. To evaluate its main parameters such as resolution, contrast, minimum temperature difference, gray scale, various DMD subsystems such as signal decoding, image normalization, synchronization drive, pulse width modulation （PWM） and DMD chips are designed. The infrared scene simulator is tested on a certain infrared missile seeker. The test results show preliminarily that the infrared scene simulator has high gray scale, small geometrical distortion and highly resolvable imaging resolution and contrast and yields high-fidelity images, thus being able to meet the requirements for the infrared scene simulation inside a laboratory.展开更多
Laser shaping was introduced to maskless projection soft lithography by using digital micro-mirror device (DMD). The predesigned intensity pattern was imprinted onto the DMD and the input laser beam with a Gaussian or...Laser shaping was introduced to maskless projection soft lithography by using digital micro-mirror device (DMD). The predesigned intensity pattern was imprinted onto the DMD and the input laser beam with a Gaussian or quasi-Gaussian distribution will carry the pattern on DMD to etch the resin. It provides a method of precise control of laser beam shapes and?photon-induced curing behavior of resin. This technology provides an accurate micro-fabrication of microstructures used for micro-systems. As a virtual mask generator and a binary-amplitude spatial light modulator, DMD is equivalent to the masks in the conventional exposure system. As the virtual masks and shaped laser beam can be achieved flexibly, it is a good method of precision soft lithography for 2D/3D microstructures.展开更多
As a key component of electro-optical systems, a Two-axis Scan mirror AssemblY(TSAY) is usually used for Line-of-Sight(LOS) precision pointing, tracking, scanning, and stabilizing. Therefore, it is necessary for a TSA...As a key component of electro-optical systems, a Two-axis Scan mirror AssemblY(TSAY) is usually used for Line-of-Sight(LOS) precision pointing, tracking, scanning, and stabilizing. Therefore, it is necessary for a TSAY to have a large angular range, high dynamic characteristics, and small mirror surface distortion. Furthermore, vibration from carriers of electro-optical systems, such as spacecraft and airplanes, is inevitable, so it is critical to guarantee the control accuracy of a TSAY under vibration. In this paper, a TSAY prototype is designed and developed. To increase the control bandwidth, structural topology optimization is applied to the TSAY’s elliptical mirror to reduce the moment of inertia, meanwhile keeping surface flatness. A flexible hinge is adopted to achieve a large angular range. To suppress the angular perturbation caused by the base linear vibration, an adaptive feedforward loop with base-integrated Micro-Electro-Mechanical System(MEMS) accelerators is constructed to enhance the TSAY’s feedback loop. Simulation and experimental results show that the TSAY prototype’s two-axis mechanical angular ranges are more than ±3.2°, the mirror surface flatness Root Mean Square(RMS) value is better than 0.04 k, and the closed-loop bandwidth is beyond 330 Hz. These are suitable for most applications. Besides, the angular perturbation caused by the base vibration can be suppressed more than 37.7% with the addition of the adaptive feedforward loop.展开更多
文摘This paper deals with vacuum UV optical coatings for micro mirror applications. High reflecting low-stress optical coatings have been developed for the next-generation of micro mechanical mirrors. The optimized metal systems are applicable in the VUV spectral region and can be integrated in the technology of MOEMS, such as spatial light modulators (SLM) and micro scanning mirrors.
基金co-supported by China Postdoctoral Science Foundation (20090461314)
文摘Dynamic infrared scene simulation is for discovering and solving the problems encountered in designing, developing and manufacturing infrared imaging guidance weapons. The infrared scene simulation is explored by using the digital grayscale modulation method. The infrared image modulation model of a digital micro-mirror device （DMD） is established and then the infrared scene simulator prototype which is based on DMD grayscale modulation is developed. To evaluate its main parameters such as resolution, contrast, minimum temperature difference, gray scale, various DMD subsystems such as signal decoding, image normalization, synchronization drive, pulse width modulation （PWM） and DMD chips are designed. The infrared scene simulator is tested on a certain infrared missile seeker. The test results show preliminarily that the infrared scene simulator has high gray scale, small geometrical distortion and highly resolvable imaging resolution and contrast and yields high-fidelity images, thus being able to meet the requirements for the infrared scene simulation inside a laboratory.
文摘Laser shaping was introduced to maskless projection soft lithography by using digital micro-mirror device (DMD). The predesigned intensity pattern was imprinted onto the DMD and the input laser beam with a Gaussian or quasi-Gaussian distribution will carry the pattern on DMD to etch the resin. It provides a method of precise control of laser beam shapes and?photon-induced curing behavior of resin. This technology provides an accurate micro-fabrication of microstructures used for micro-systems. As a virtual mask generator and a binary-amplitude spatial light modulator, DMD is equivalent to the masks in the conventional exposure system. As the virtual masks and shaped laser beam can be achieved flexibly, it is a good method of precision soft lithography for 2D/3D microstructures.
基金the support by the National Natural Science Foundation of China (No. 11672016)
文摘As a key component of electro-optical systems, a Two-axis Scan mirror AssemblY(TSAY) is usually used for Line-of-Sight(LOS) precision pointing, tracking, scanning, and stabilizing. Therefore, it is necessary for a TSAY to have a large angular range, high dynamic characteristics, and small mirror surface distortion. Furthermore, vibration from carriers of electro-optical systems, such as spacecraft and airplanes, is inevitable, so it is critical to guarantee the control accuracy of a TSAY under vibration. In this paper, a TSAY prototype is designed and developed. To increase the control bandwidth, structural topology optimization is applied to the TSAY’s elliptical mirror to reduce the moment of inertia, meanwhile keeping surface flatness. A flexible hinge is adopted to achieve a large angular range. To suppress the angular perturbation caused by the base linear vibration, an adaptive feedforward loop with base-integrated Micro-Electro-Mechanical System(MEMS) accelerators is constructed to enhance the TSAY’s feedback loop. Simulation and experimental results show that the TSAY prototype’s two-axis mechanical angular ranges are more than ±3.2°, the mirror surface flatness Root Mean Square(RMS) value is better than 0.04 k, and the closed-loop bandwidth is beyond 330 Hz. These are suitable for most applications. Besides, the angular perturbation caused by the base vibration can be suppressed more than 37.7% with the addition of the adaptive feedforward loop.
