相位型光寻址空间光调制器稳定性分析

基于光寻址空间光调制器的等效电路仿真及稳定性测试实验,对纯相位型光寻址空间光调制器的稳定性进行分析和优化。结果表明,光阀液晶层的电压脉冲波形会引起光寻址空间光调制器对读出光的相位调制波动,而驱动电压频率与写入光强度同时影响相位调制波动幅度及相位调制量。由实验测量得到的光寻址空间光调制器的相位改变量曲线可知:当驱动电压周期比响应时间小95%时,最大相位改变量对应的相位波动率减小为0.35%,但此时相位调制能力仅为0.8λ;通过优化光寻址空间光调制器驱动条件参数,可获得1λ的相位调制能力,同时最大相位改变量对应的相位波动率为1%。     

多信道铁电液晶空间光调制器

描述了矩阵电寻址铁电液晶(FLC)多信道透射型空间光调制器(SLM)的结构和运转特性，测量了器件的二进制相位调制的空间和时间特性。     

微阵列光寻址生化传感器系统性能研究

该文介绍一种基于电解质溶液-绝缘层-半导体(EIS)结构的光、机、电一体化的微阵列光寻址电位传感器系统(LAPS)。文中研讨了LAPS的基本原理和微阵列光寻址电位传感器系统的制造。通过实验证明了芯片厚度、调制频率、曲线线性度对系统性能的影响,获得多种生化参数的光寻址测试结果。     

空间光调制器和光存储器

光计算机的关键部件是空间光调制器。空间光调制器是由寻址材料和光调制材料组成的二维三端子元件。读出光的强度或相位分布是根据存储光的强度分布而进行调制。这就是空间调制器的最基本的功能。如果存储光使用白光,读出光使用激光,就能进行不相干或相干变换。除此之外,还有存储器件、放大器、运算器的功能。     

氢化非晶硅pin二极管型光寻址空间光调制器的研制

报道了用氢化非晶硅（α－Ｓｉ：Ｈ）ｐｉｎ二极管作光敏层，扭曲向列型液晶（ＴＮＬＣ）作电光调制层的光寻址空间光调制器（ＯＡＳＬＭ）的设计、制作与性能测试．结果表明制得的（ＯＡＳＬＭ）分辨率大于２０ｌｐ／ｍｍ；在３００ｌｕｘ白光写入时对比度高于２５：１；白光写入灵敏度约３ｌｕｘ。     

多量子阱空间光调制器二维列阵

用MBE技术生长GaAs／AlGaAs多量子阱材料，研制出8×8独立寻址反射型空间光调制器列阵，对列阵的光反射谱、光电流谱、电场调制特性及电学特性进行了全面的测试，并对列阵的均匀性进行了分析．     

写光波长对光折变空间光调制器分辨率的影响

结合光学实验及数值模拟,对写光波长的变化对基于Bi12SiO20(BSO)光折变晶体的光寻址空间光调制器(SLM)的调制传递函数(MTF)空间频率响应的影响进行了分析.光学实验分析结果和数值模拟分析相吻合,写光波长以及电荷位置对SLM的MTF空间频率响应的影响在本质上得到了统一.根据分析及讨论,较短波长的写光有利于获得较好的MTF空间频率响应.     

一种基于组合光调制的光侧电度表的设计

用矩阵方法分析了电光调制在前、磁光调制在后的组合光调制。得出了能利用这种组合光调制对电能实现光测结论，进而设计出光测电度表。     

辅助光注入下半导体光放大器的快慢光性能

随着全光网络的快速发展,快慢光技术受到了广泛关注。为了研究半导体光放大器(SOA)的快慢光效应,文章构建了辅助光注入半导体光放大器的理论模型。比较了辅助光注入SOA前后,直流电流、调制电流、调制频率、相移以及增益系数等参数对相位延时量的影响。仿真结果表明：辅助光的注入使输出信号光由慢光变为快光,辅助光功率越强,效果越明显。同时,注入辅助光信号后,直流电流越大,相位延时量越大;调制电流、调制频率、相移及增益系数越大,相位延时量越小。     

激光信号的空间光调制关键技术综述

空间光调制技术是利用各种手段对光波在空间上的传输状态进行加工处理和控制的一项技术,被广泛应用于光通信、光学印刷,以及神经网络计算等领域。文章对激光信号的空间光调制技术目前的国内外研究现状进行了详细的分析,对空间光调制技术目前存在的技术挑战进行了详细阐述,并展望了今后该技术的发展方向。     

采用空间光调制器的光变图像光刻系统

用激光干涉型光学头产生干涉条纹,采用空间光调制器(SLM)进行子图输入实现光学可变图像(DVD)的快速光刻,分辨率可达5080dpi,平均运行效率达8O00 dots s(1270pdpi)以上。研制了大幅面激光光刻系统,给出了实验结果。     

基于DHT的光OFDM系统PAPR抑制算法

针对光OFDM系统存在高峰均功率比(PAPR),提出了一种基于离散哈特利变换(DHT)的选择映射抑制算法。采用快速哈特利逆变换(IFHT)代替传统的快速傅立叶逆变换(IFFT)和Hermi t i an对称算法,并结合非对称限幅法产生满足光OFDM系统要求的正、实值信号送入光纤信道。     

Free space adaptive optical interconnect at 1.25 Gb/s, with beam steering using a ferroelectric liquid-crystal SLM

A free space adaptive optical interconnect is reported, in which an optically modulated channel from a vertical-cavity surface-emitting laser at 1.25 Gb/s is steered using reconfigurable binary phase gratings displayed on a ferroelectric liquid crystal on silicon (LCOS) spatial light modulator (SLM), to correct for misalignment. The optical system, and addressing scheme to maintain a transparent optical path, is described. The measured optical losses total 13.6 dB, sufficient to give a bit error rate (BER) of 10/sup -12/ with current optical transmitter and receiver technology. This is, to our knowledge, the first demonstration of a high-speed data transmission through an adaptive optical interconnect using an "off-the-shelf" commercial ferroelectric display panel.     

Trinary flip-flops using Savart plate and spatial light modulator for optical computation in multivalued logic

The memory devices in multi-valued logic are of most significance in modem research. This paper deals with the implementation of basic memory devices in multi-valued logic using Savart plate and spatial light modulator （SLM） based optoelectronic circuits. Photons are used here as the carder to speed up the operations. Optical tree architecture （OTA） has been also utilized in the optical interconnection network. We have exploited the advantages of Savart plates, SLMs and OTA and proposed the SLM based high speed JK, D-type and T-type flip-flops in a trinary system.     

Trinary flip-flops using Savart plate and spatial light modu-lator for optical computation in multivalued logic

The memory devices in multi-valued logic are of most significance in modern research. This paper deals with the imple-mentation of basic memory devices in multi-valued logic using Savart plate and spatial light modulator (SLM) basedoptoelectronic circuits. Photons are used here as the carrier to speed up the operations. Optical tree architecture (OTA) hasbeen also utilized in the optical interconnection network. We have exploited the advantages of Savart plates, SLMs andOTA and proposed the SLM based high speed JK, D-type and T-type flip-flops in a trinary system.     

OFDM系统中一种联合改进的低复杂度SLM峰均比抑制技术

高的峰值平均功率比(Peak-to-Average Power Ratio,PAPR)是光正交频分复用(Optical Orthogonal Frequency Division Multiplexing,O-OFDM)系统的一个主要缺点,选择性映射(Selective Mapping,SLM)法能有效降低高PAPR出现的概率,但它的计算复杂度较高.一些低复杂度的SLM方案能够有效地降低复杂度,但同时也降低了PAPR的抑制性能.为了平衡这两个因素,将低复杂度SLM方案与次优选择的思想相结合,文章提出了一种联合改进的PAPR抑制方案.在低复杂度方案中,通过将一个复频域信号分为两个实信号,再利用快速傅里叶变换(Fast Fourier Transform,FFT)的平移和反折性质将其重建成新的信号,以得到更多的备选信号,如此便能降低计算复杂度.然后,再结合次优选择的思想,选择PAPR最小的一路以得到最优的PAPR抑制性能.仿真结果验证了该方案的有效性.     

光OFDM系统中一种改进的SLM峰均比抑制方案

针对光正交频分复用(O-OFDM)系统中峰值平均功 率比(PAPR)较高的缺点,对PAPR抑制技术的选择性 映射法(SLM) 进行了深入研究。基于低复杂度SLM方案的深入研究,提出了一种改进的次PAP R选择的思 想与低复杂度SLM相结合的PAPR抑制方案。改 进的SLM方案能够成倍降低传统SLM方案的计算复杂 度。仿真分析表明,改进的SLM方案在载波数为256的O-OFDM系统中,计算复杂度能降低50%以上,并 且随着子载波数的增加,其复杂度降低程度更为高效;同时,该改进的SLM方案又能使其PAPR抑制性能优于传统的SLM方案,从而进一步提升了低复杂度SLM 方案的实用价值。     

Holographic optical switching: the “ROSES” demonstrator

The design, assembly, and performance of a prototype 1×8 free-space switch demonstrator using reconfigurable holograms are reported. Central to the switch fabric is a ferroelectric liquid crystal (FLC) on silicon spatial light modulator (SLM) deposited with a 540×1 array of highly reflective and planar mirror strips. The input and output ports of the switch are fabricated as a linear array of silica planar waveguides connected to single-mode fibers, and the holographic beam-steerer operates without the need for adjustment or dynamic alignment. The waveguide array and the single Fourier transform lens for the 2f holographic replay system are housed in an opto-mechanical mount to provide stability. The switch operates at 1.55 μm wavelength and has a designed optical bandwidth of >60 nm. The first measured insertion loss and crosstalk figures are 16.9 dB and -19.1 dB, respectively. Improvements in SLM performance, the use of new addressing schemes and the introduction of better alignment techniques are expected to improve these figures considerably. The preliminary performance of a 3×3 optical crossconnect is also presented to show that this technology is scalable to N×N switching fabrics     

超音速共形光学系统动态热差实时校正研究

随着科技的发展,高速度飞行器对成像质量的要求越来越高。研究了含共形整流罩系统在超音速飞行时由于摩擦生热对其产生的光机性能影响,设计了应用长径比为1的共形整流罩的共形光学系统,系统采用楔形镜进行视场扫描,瞬时视场2=4,扫描视场2=60,完成了速度为3Ma、攻角为0共形整流罩空气动力学仿真实验,得到了共形整流罩在超音速飞行情况下的表面温度分布值,通过流固耦合,计算出整流罩在高速飞行时不同时间段的面型变化量。通过拟合,将热形变量以Zernike系数的形式施加到共形光学系统中,观察其对成像质量的影响。结果表明:共形整流罩在飞行中所引入的动态像差会对光学系统的成像质量产生影响。为保证系统精度,文中通过采用空间光调制器（Spatial Light Modulator,SLM）对不同时刻的像差进行校正,校正后系统成像质量接近衍射极限,实现了对共形光学系统在高速飞行下所产生的动态热像差进行校正,对高精度飞行器有着重要科学意义。     

Widely tunable wavelength spacing dual-wavelength single longitudinal mode erbium doped fiber laser

A simple widely tunable wavelength spacing dual-wavelength single longitudinal mode (SLM) erbium doped fiber laser (EDFL) based on cascaded fiber Bragg gratings (FBGs) and birefringent fiber filter is proposed and demonstrated. Experimental results show that the lasing wavelength spacing is widely tunable in a range from 2 nm to 18 nm, which has potential to generate frequency tunable terahertz (THz) waves by beating the lasing dual-wavelength in a high speed photodetector. The birefringent fiber filter acts as an ultra-narrow bandpass filter and benefits the simultaneous oscillation of dual-wavelength in a single laser cavity. The output peak power of the lasing dual-wavelength is approximately equalized at room temperature, and a high optical signal-to-noise ratio (OSNR) is realized in the whole tuning range. The SLM operation of dual-wavelength fiber laser is verified by Fabry–Perot (F–P) scanning interferometer, and the clear eye diagram proves that the proposed fiber laser is effective in the application of fiber optic communication system.