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Woofer–tweeter adaptive optical structured illumination microscopy 被引量:3
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作者 QINGGELE LI MARC REINIG +4 位作者 DAICH KAMIYAMA BO HUANG XIAODONG TAO ALEX BARDALES JOEL KUBBY 《Photonics Research》 SCIE EI 2017年第4期329-334,共6页
A woofer–tweeter adaptive optical structured illumination microscope(AOSIM) is presented. By combining a low-spatial-frequency large-stroke deformable mirror(woofer) with a high-spatial-frequency low-stroke deformabl... A woofer–tweeter adaptive optical structured illumination microscope(AOSIM) is presented. By combining a low-spatial-frequency large-stroke deformable mirror(woofer) with a high-spatial-frequency low-stroke deformable mirror(tweeter), we are able to remove both large-amplitude and high-order aberrations. In addition, using the structured illumination method, as compared to widefield microscopy, the AOSIM can accomplish highresolution imaging and possesses better sectioning capability. The AOSIM was tested by correcting a large aberration from a trial lens in the conjugate plane of the microscope objective aperture. The experimental results show that the AOSIM has a point spread function with an FWHM that is 140 nm wide(using a water immersion objective lens with NA=1.1) after correcting a large aberration(5.9 μm peak-to-valley wavefront error with 2.05 μm RMS aberration). After structured light illumination is applied, the results show that we are able to resolve two beads that are separated by 145 nm, 1.62× below the diffraction limit of 235 nm. Furthermore, we demonstrate the application of the AOSIM in the field of bioimaging. The sample under investigation was a green-fluorescentprotein-labeled Drosophila embryo. The aberrations from the refractive index mismatch between the microscope objective, the immersion fluid, the cover slip, and the sample itself are well corrected. Using AOSIM we were able to increase the SNR for our Drosophila embryo sample by 5×. 展开更多
关键词 AO SIM woofer tweeter adaptive optical structured illumination microscopy
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支撑系统对低音扬声器特性的影响 被引量:3
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作者 谢守华 陈进 《电声技术》 2011年第3期16-18,共3页
通过对比测试低音扬声器的定心支片和复合边这两个起支撑作用部件受力位移的非线性特性,分析、解释了扬声器的相关特性与它们之间的联系,同时为解决扬声器的可靠性问题和改善失真问题提供相关的实践经验。
关键词 低音扬声器 定心支片 复合边 位移 谐振频率
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电动式扬声器单元中的降低失真问题
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作者 А.ЖУРЕНКОВ 俞锦元 《电声技术》 2013年第9期17-20,共4页
探讨了在电动式低音扬声器单元中非线性失真的原因,并且提出了减少偶次谐波的带对称磁路的电动式扬声器单元的某些结构方案。介绍了已进行的降低偶次谐波的方法即应用双低频扬声器单元,该方法还能减小声系统箱体的容积。
关键词 低音扬声器 非线性失真 偶次谐波 声阻抗板
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低频滤波器和低音单元的相互作用
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作者 C.Д.БaTb 俞锦元 《电声技术》 2012年第1期19-22,25,共5页
在三分频,四分频音箱制作和调试中,人们经常发现在55~120 Hz的低频段幅频响应曲线有几个分贝的提升,影响了放音音质。揭示了此时分频器(低频滤波器)所接的扬声器单元是容性负载才造成了幅频特性上不希望的声压提升。给出了频率比值的概... 在三分频,四分频音箱制作和调试中,人们经常发现在55~120 Hz的低频段幅频响应曲线有几个分贝的提升,影响了放音音质。揭示了此时分频器(低频滤波器)所接的扬声器单元是容性负载才造成了幅频特性上不希望的声压提升。给出了频率比值的概念,用以判断低频峰值出现的可能。最后给出了几种实用的解决方案。希望对三、四分频的音箱设计者有效克服55~120 Hz处低频响应隆起有所帮助。 展开更多
关键词 低频滤波器 低音单元 扬声器系统
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三开口联动低音箱
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作者 徐耀忠 徐橙 《电声技术》 2015年第2期24-28,68,共6页
多开口联动低音箱发明已多年,由于种种原因本发明并不为电声界所了解。分析已有低音箱,如倒相式音箱,是在封闭箱基础上增设亥姆霍兹共振器,以提高音箱的低音效果。单开口、双开口带通箱是在倒相箱的基础上再增设一个封闭箱或亥姆霍兹共... 多开口联动低音箱发明已多年,由于种种原因本发明并不为电声界所了解。分析已有低音箱,如倒相式音箱,是在封闭箱基础上增设亥姆霍兹共振器,以提高音箱的低音效果。单开口、双开口带通箱是在倒相箱的基础上再增设一个封闭箱或亥姆霍兹共振箱,所以低音放音效果有所提高,但总体的改进不大。三开口联动低音箱是由音盆联动的三个亥姆霍兹共振箱组成,具有电一声转换效率高、声输出功率大、工作频率范围宽等一系列优点,从不同角度定性分析了这些优点。 展开更多
关键词 驱动力联动 音盆振幅联动 三开口联动低音箱
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改善收录机音质的方法
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作者 卢育辉 凌宇征 《电子机械工程》 2004年第6期45-46,64,共3页
讨论了收录机的音箱腔体、导声筒等的外形设计,以及扬声器的合理安装等几个方面的问题,以改善收录机的音质。
关键词 腔体 导声筒 收录机音质
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Cascading optofluidic phase modulators for performance enhancement in refractive adaptive optics
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作者 Pouya Rajaeipour Kaustubh Banerjee +2 位作者 Alex Dorn Hans Zappe Caglar Ataman 《Advanced Photonics》 EI CSCD 2020年第6期47-56,共10页
We discuss the implementation and performance of an adaptive optics(AO)system that uses two cascaded deformable phase plates(DPPs),which are transparent optofluidic phase modulators,mimicking the common woofer/tweeter... We discuss the implementation and performance of an adaptive optics(AO)system that uses two cascaded deformable phase plates(DPPs),which are transparent optofluidic phase modulators,mimicking the common woofer/tweeter-type astronomical AO systems.One of the DPPs has 25 electrodes forming a keystone pattern best suited for the correction of low-order and radially symmetric modes;the second device has 37 hexagonally packed electrodes better suited for high-order correction.We also present simulation results and experimental validation for a new open-loop control strategy enabling simultaneous control of both DPPs,which ensures optimum correction for both large-amplitude low-order,and complex combinations of low-and high-order aberrations.The resulting system can reproduce Zernike modes up to the sixth radial order with stroke and fidelity up to twice better than what is attainable with either of the DPPs individually.The performance of the new AO configuration is also verified in a custom-developed fluorescence microscope with sensorless aberration correction. 展开更多
关键词 adaptive optics woofer/tweeter phase modulation OPTOFLUIDICS aberration correction open-loop control
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