Diffractive optical elements have a large number of industrial applications, such as beam shaping and optical filtering. Traditionally, these elements modulate the phase of the incoming light or its amplitude, but not...Diffractive optical elements have a large number of industrial applications, such as beam shaping and optical filtering. Traditionally, these elements modulate the phase of the incoming light or its amplitude, but not both. To overcome this limitation, full complex-amplitude modulation diffractive optical elements were developed. Well-established integrated circuit fabrication steps were employed to fabricate the devices with high precision. Using this approach, the new element's optical performances are improved also for near field operations. With this device it is possible to obtain 100% efficient spatial filtering and low noise reconstructed images.展开更多
面向机载探测系统大视场光学成像的需求,开展了大视场光学成像系统光学设计、自由曲面光学元件超精密加工、形位误差同步检测以及系统集成与成像实验研究。首先,采用视场扩展法进行大视场自由曲面离轴反射光学系统的设计;其次,进行铝合...面向机载探测系统大视场光学成像的需求,开展了大视场光学成像系统光学设计、自由曲面光学元件超精密加工、形位误差同步检测以及系统集成与成像实验研究。首先,采用视场扩展法进行大视场自由曲面离轴反射光学系统的设计;其次,进行铝合金自由曲面反射镜纳米精度加工和高频抑制工艺探索,并实现了基于计算全息元件的自由曲面形位高精度检测;最后,进行了光学系统的装调集成与成像实验。结果表明,系统的视场角为30°×5°,全视场光学传递函数值大于0.7,接近衍射极限,最大像元均方根半径为2.075μm,自由曲面光学元件的面形精度均方根(Root Mean Square,RMS)值优于20 nm,位置精度优于1μm,装配集成后能够满足大视场高分辨的场景使用要求,同时具备稳定可靠和快响制造等特点。展开更多
Hastening transmission by efficiently providing compression is our goal in this work. Image compression consists in reducing information size representing an image. Elimination of redundancies and non-pertinent inform...Hastening transmission by efficiently providing compression is our goal in this work. Image compression consists in reducing information size representing an image. Elimination of redundancies and non-pertinent information enables memory space minimization and thus fast data transmission. Optics can offer an alternative choice to overcome the limitation of numerical compression algorithms. In this paper, we propose real-time optical image compression using a real Fourier plane to save time required for compression by using the principles of coherent optics. Digital and optical simulation results are presented and analyzed. An optical compression decompression setup is demonstrated using two different SLMs (SEIKO and DisplayTech). The purpose of this method is to simplify our earlier method, improve the quality of reconstructed image, and avoid the disadvantages of numerical algorithms.展开更多
文摘Diffractive optical elements have a large number of industrial applications, such as beam shaping and optical filtering. Traditionally, these elements modulate the phase of the incoming light or its amplitude, but not both. To overcome this limitation, full complex-amplitude modulation diffractive optical elements were developed. Well-established integrated circuit fabrication steps were employed to fabricate the devices with high precision. Using this approach, the new element's optical performances are improved also for near field operations. With this device it is possible to obtain 100% efficient spatial filtering and low noise reconstructed images.
文摘面向机载探测系统大视场光学成像的需求,开展了大视场光学成像系统光学设计、自由曲面光学元件超精密加工、形位误差同步检测以及系统集成与成像实验研究。首先,采用视场扩展法进行大视场自由曲面离轴反射光学系统的设计;其次,进行铝合金自由曲面反射镜纳米精度加工和高频抑制工艺探索,并实现了基于计算全息元件的自由曲面形位高精度检测;最后,进行了光学系统的装调集成与成像实验。结果表明,系统的视场角为30°×5°,全视场光学传递函数值大于0.7,接近衍射极限,最大像元均方根半径为2.075μm,自由曲面光学元件的面形精度均方根(Root Mean Square,RMS)值优于20 nm,位置精度优于1μm,装配集成后能够满足大视场高分辨的场景使用要求,同时具备稳定可靠和快响制造等特点。
文摘Hastening transmission by efficiently providing compression is our goal in this work. Image compression consists in reducing information size representing an image. Elimination of redundancies and non-pertinent information enables memory space minimization and thus fast data transmission. Optics can offer an alternative choice to overcome the limitation of numerical compression algorithms. In this paper, we propose real-time optical image compression using a real Fourier plane to save time required for compression by using the principles of coherent optics. Digital and optical simulation results are presented and analyzed. An optical compression decompression setup is demonstrated using two different SLMs (SEIKO and DisplayTech). The purpose of this method is to simplify our earlier method, improve the quality of reconstructed image, and avoid the disadvantages of numerical algorithms.
