光滤波器

The application of an appropriate apodization film to an ordinary lens makes the point amplitude response asymptotic to a Dirac-delta function, or causes an arbitrarily narrow depth of focus. This implicates that we may achieve lateral or axial superresolution through implementing an apodization film.

运用适当形式的光瞳滤波器可以改变成像系统点振幅响应的分布，使其具有类似于冲击函数(Dirac-delta函数)的形式，这样就有可能实现光学超分辨，但变迹术的运用往往会因其强烈的旁瓣效应而导致成像系统对比度的急剧下降。

At last, optical half /full adders based on single SOA and several optical bandpass filter are theoretically proposed.

最后从理论上提出了基于单个SOA和若干个并联的滤波器组合的全光半加器和全加器。

It is a promising approach to achieving high-speed all-optical signal processing based on the combination of semiconductor optical amplifier and optical bandpass filter.

将半导体光放大器和滤波器组合使用是实现高速全光信号处理的有效途径。

In this paper, principle and technique of volume holographic storage are presented such as volume grating formation, Bragg diffraction, and horizontal angle selectivity.

本论文介绍了体全息存储原理及技术，包括体光栅的形成和布拉格衍射、衍射效率、水平角度选择性，还介绍了相干光学信息处理系统、Vander Lugt 滤波器的形成过程，给出了多重匹配滤波器相关的运算过程，最后介绍了子波变换的定义以及光学子波变换。

This technique uses a spiral phase plate with a small central aperture placed on the Fourier plane of so imaging system. If the spiral phase filter is rotated by a certain angle around its central axis, a phase shift between the zero-order spatial frequency component and the remaining of the object is produced, and the magnitude of this phase shift is proportional to the rotation angle. Using this property, we can record a sequence of intensity distribution of the output beams corresponding to different rotation angles, and then digitally reconstruct the objects by using a phase-shifting algorithm. Both the theoretical analysis and simulation experiment results demonstrate the feasibility of this approach.

在成像系统的频谱面上放置中心带有一通光孔径的螺旋相位板，在输出面上记录输入物体经螺旋相位滤波后的输出像；将螺旋相位滤波器绕轴旋转一定角度，通过中心光孔的零频成份与其他高频成份间会产生与旋转角度成正比的相移；利用这一特点，通过记录多幅对应不同旋转角度的输出光场强度分布图，然后再用一定的相移算法实现被记录物体相位分布的数字再现。

This technique uses a spiral phase plate with a small central aperture placed on the Fourier plane of an imaging system. If the spiral phase filter is rotated by a certain angle around its central axis,a phase shift between the zero-order spatial frequency component and the remaining of the object is produced,and the magnitude of this phase Shift is proportional to the rotation angle. Using this property,we can record a sequence of intensity distribution of the output beams corresponding to different rotation angles,and then digitally reconstruct the objects by using a phase-shifting algorithm. Both the theoretical analysis and simulation experiment results demonstrate the feasibility of this approach.

在成像系统的频谱面上放置中心带有一通光孔径的螺旋相位板，在输出面上记录输入物体经螺旋相位滤波后的输出像；将螺旋相位滤波器绕轴旋转一定角度，通过中心光孔的零频成份与其他高频成份间会产生与旋转角度成正比的相移；利用这一特点，通过记录多幅对应不同旋转角度的输出光场强度分布图，然后再用一定的相移算法实现被记录物体相位分布的数字再现。

When used in the case of oblique incidence or large cone angle incidence, this filter reduces shift of central wavelength significantly while still maintaining its filter characteristics.

这种滤波器使用于斜入射光和大光锥角照明时，不仅中心波长移动显著减少，而且特性仍能保持良好。

The relation between the ultrasonic frequency f and the wavelength λ0 was deduced. The relations between the diffraction angle θd,the acoustic polar angle θa and the incident angle θi were calculated.

推导出超声波频率f和光波波长λ0的调谐关系；计算出滤波器的光谱分辨率R和集光能力δθi；光入射角θi与衍射角θd、声入射角θa之间的关系。

The inverted wavelength conversion of the nonreturn to zero and the format conversion from NRZ to pseudo return to zero are demonstrated synchronously based on single SOA and an optical bandpass filter with 0.32 nm bandwidth. The conversion results depend on the OBF detuning as respect to the probe carrier.

利用半导体光放大器和带宽为0.32 nm的可调窄带滤波器同时实现了40 Gbit/s的非归零信号的反相波长转换和非归零到伪归零信号的码型转换，波长转换和码型转换的结果差异取决于滤波器中心波长相对于探测光波长的失谐量。

Using this method, wide dimming range can be achieved with narrow frequency range and constant DC link voltage. And the lamp current keeps perfect sine wave all the time, which means low lamp current crest factor is obtained. Its validity is verified by simulation and experiment.

本章最后提出了一种基于T型滤波器的新型的调光方法，采用此方法可以在保持逆变器直流母线电压和开关占空比不变的情况下，只需很窄的频率范围就能达到非常宽的调光范围，而且在整个调光范围内灯电流都基本上是完美的正弦波，这就意味着可以始终保持很低的灯电流波峰因数，仿真和实验结果充分验证了它的优点。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。