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《光学学报》2010,(10)
为满足探测1,2丙二醇二硝酸脂有毒气体浓度的红外探测元件抑制带截止深度深、通带内平均透射比高、波纹系数小等要求,采用等效折射率理论与局部优化相结合的设计方法,选用PbTe/ZnSe作为高低折射材料,采用长波通膜系、短波通膜系以及双半波膜系设计了截止深度深、双通道、通带宽度合适的红外滤光片,通带分别为5.9~6.2μm及11.9~12.2μm,通带内平均透射比分别在90%及65%以上;对所设计的膜系进行了薄膜物理厚度和膜层折射率的误差分析。分析表明,薄膜制备时沉积速率精度应控制在3.5%以内,材料折射率的变化应控制在3%以内,与膜层折射率相比,薄膜物理厚度对平均透射比的影响小,并且双半波膜系对厚度以及折射率变化更敏感。 相似文献
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用激光测量液体的折射率已有许多报道,但测量方法比较繁琐,且精确度不够高.本文介绍一种用激光测量液体折射率的简单方法,此方法利用光线传播的几何关系,对液体折射率作定量测试.该方法具有设备简单、费用低廉、测量精度高等优点.1实验原理及方法利用临界角的概率束来测量液体的折射率,如图1所示.当激光束沿一条半径进入液体,即使入射光束对准容器的中心G点射入液体时,不发生折射,而在G点射出的光束发生了折射,折射角大于入射角.当人射角i增大,直到使折射角达到90°时,折射光束沿容器的直边传播.继续转动容器增大人射角,激光束… 相似文献
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为了节省稀有昂贵的冰洲石晶体材料,采用冰洲石晶体与光学玻璃组合的方法,设计了一种新型起偏棱镜。设计样品为ZBaF3玻璃中间加冰洲石晶体薄片的三元结构,并通过大折射率液态胶合剂溴代萘胶合而成。该棱镜既可以实现o光的偏振输出,又可实现入射光的90°转向。实验测试结果表明:设计棱镜的透射比在80%以上,消光比优于1-0 3。理论分析和性能测试均表明:三元结构冰洲石-玻璃90°转向起偏棱镜在一般情况下,可以取代相应的纯冰洲石晶体材料的偏光棱镜。 相似文献
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费米折射率波导的包层吸收模谱特性和溶液浓度传感研究 总被引:3,自引:0,他引:3
采用0.004AgNO3-0.996NaNO3混合熔融盐,用离子交换技术在德国B270光学玻璃上制备了费米折射率分布渐变波导,理论分析了费米折射率分布渐变波导的包层吸收模谱特性.导波损耗测试实验验证了解析结果.在此基础上,提出了一种用于液体包层吸收损耗测试的双样品盒串连的波导回路.测试结果证实表征溶液包层吸收特征的折射率虚部与溶液浓度之间具有十分显著的线性关系,测试灵敏度与波导的模式和波导参量有关,尤其与波导层厚度有非常敏感的关联性.利用这个关系传感测试了13种不同浓度的耐晒果绿染料水溶液样品的浓度,结果显示测试值与实际配制浓度值的均方差小于0.07%. 相似文献
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A new fabrication technology for three-dimensionally buried silica on silicon optical waveguide based on deep etching and thermal oxidation is presented.Using this method,a silicon layer is left at the side of waveguide.The stress distribution and effective refractive index are calculated by using finite element method and finite different beam propagation method,respectively.The results indicate that the stress of silica on silicon optical waveguide fabricated by this method can be matched in parallel and vertical directions and stress birefringence can be effectively reduced due to the side-silicon layer. 相似文献
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Mingfu Zhang Hengzhi Chen Bin Yang Wenwu Cao 《Applied Physics A: Materials Science & Processing》2009,97(4):741-744
Layered-perovskite ferroelectric Bi2.85La0.15TiNbO9 (LBTN) optical waveguiding thin films were grown on fused silica substrates by pulsed laser deposition (PLD). X-ray diffraction
(XRD) revealed that the film is highly (00l) textured. We observed sharp and distinct transverse electric (TE) and transverse magnetic (TM) multimodes and measured the
refractive indices of LBTN thin films at 632.8 nm. The ordinary and extraordinary refractive indices were calculated to be
n
TE=2.358 and n
TM=2.464, respectively. The film homogeneity and the film-substrate interface were analyzed using an improved version of the
inverse Wentzel–Kramer–Brillouin (iWKB) method. The refractive index of the film remains constant at n
0 within the waveguiding layer. The average transmittance of the film is 70% in the wavelength range of 400–1400 nm and the
optical waveguiding properties were evaluated by the optical prism coupling method. Our results showed that the LBTN films
are very good electro-optical active material. 相似文献
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光学材料光学均匀性检测方法分析 总被引:2,自引:0,他引:2
光学均匀性是光学材料的重要指标,直接影响到透射光学系统的波面质量,改变系统的波相差。惯性约束聚变(Inertial Confine Fusion,ICF)激光驱动器的研制要求对材料的光学均匀性进行高精度的检测,同时兼顾洁净度要求。实验中利用斐索干涉仪实现了大口径光学材料光学均匀性的检测,并与国外检测数据进行了对比,对检测过程中的影响因素主要包括样品的厚度测量偏差及折射系数偏差进行了分析。结果表明,样品的厚度测量偏差及折射系数偏差对结果的影响较小,可以忽略。同时用两种干涉仪专用软件对大量样品测量数据进行处理,对比了不同干涉仪光学均匀性的计算结果,表明这两种情况下对光学均匀性的处理结果相符,解决了大口径光学坯件光学均匀性的检测问题。 相似文献
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V. Kudriašov E. Gaižauskas V. Sirutkaitis 《Applied Physics A: Materials Science & Processing》2008,93(2):571-576
We present a study of the refractive index modifications spontaneously induced by infrared femtosecond filaments propagating
in the bulk of transparent solids. It was found that extended modified refractive index channels up to several mm in length
can be formed under loose focusing conditions in fused silica. The observed birefringence zone at the beginning of these channels
is attributed to the anisotropic stress induced via nonlinear losses in the high intensity region of the filament. 相似文献
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Porous Si made from (110) Si wafers exhibits strong in-plane optical anisotropy (birefringence) in the visible and near-IR ranges. Oxidation of the birefringent porous Si results in the formation of birefringent porous silica. We demonstrate that the degree of the birefringence of porous silica can be controlled by the oxidation condition, and very small birefringence can be achieved. The smallest anisotropy of the refractive index (Δn) is 0.001, which is about ten times smaller than that of quartz. The small birefringence allows us to produce true zero-order wave plates operating in the UV range. 相似文献
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Gong SH Stolz A Myeong GH Dogheche E Gokarna A Ryu SW Decoster D Cho YH 《Optics letters》2011,36(21):4272-4274
Anodic aluminum oxide (AAO) films with different pore sizes were prepared to modulate the effective refractive index and birefringence. To investigate the relationship between the refractive index and the pore size of the AAO film, optical constants were obtained using a prism coupler with various lasers. With experimental results, the dispersion curve of alumina itself without pores was extracted using a theoretical anisotropic model. We demonstrated that AAO films could offer a wide range of refractive index and birefringence values for optical device applications. Furthermore, index profiles as a function of the thickness of the AAO films were obtained by inverse Wentzel-Kramer-Brillouin approximation to examine the optical homogeneity. 相似文献
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提出一种具有温度自校准功能的光纤折射率(RI)传感器,传感头结构由2段很短的多模光纤(MMF)之间夹熔一段对折射率不敏感的光纤布拉格光栅(FBG)构成,传感头总长度为14 mm,FBG可以为折射率测量提供良好的温度校准功能。实验结果证明,该传感器的折射率灵敏度为126 nm。其干涉光谱共振波长的温度灵敏度为35.09 pm/℃,用于温度校准的FBG的温度灵敏度为11.14 pm/℃。相比于普通的折射率传感器,这种具有温度自校准功能的折射率传感器具有良好的实用前景。 相似文献
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V. K. Miloslavsky E. D. Makovetsky L. A. Ageev K. S. Beloshenko 《Optics and Spectroscopy》2009,107(5):811-815
A method for calculating the refractive index of optical fused silica by applying the model of effective permittivity of composite
homogeneous media is proposed and realized. The calculation was performed using the tabular data of the refractive index of
crystalline α quartz and the ratio of the quartz glass and α quartz densities. It was suggested that fused silica contains
nanosized pores with a glass filling number q immersed in a matrix with a density differing from the α quartz density by a factor of κ, where κ is slightly less than unity.
It was established that the Maxwell-Garnett model makes it possible to calculate the refractive index of quartz glass and
its dispersion in the transparency range (404 nm ≤ λ ≤ 671 nm) with a deviation less than 0.0002 from the tabular values.
The calculated and experimental values coincide at q = 0.155 and κ = 0.986. 相似文献
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In this paper, we present a method for enhancing the measurement capability of refractive index homogeneity for parallel optical components, which phase-shifting interferometry cannot handle with. With the help of wavelength-modulation phase-shifting interferometry, a series of multiple-surface interference fringes are obtained and analyzed by Fourier transform. Based on the fact that the interference fringe corresponding to each interference cavity has its own variation frequency, the wavefront aberrations induced by each interference cavity are obtained and the refractive index homogeneity is then obtained. It is proved by experiment that the enhanced method can measure the refractive index homogeneity of parallel optical components more accurately and conveniently compared with the traditional measurement approach. Therefore, it will have potential application forwards in optical measurement field. 相似文献
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提出了一种光纤折射率分布的测量方法,采用白光扫描干涉技术,并在参考镜上构造与光纤样品相同的结构来克服白光相干长度短的限制,优化了光路,提高了干涉条纹间的对比度。采用与白光干涉信号的包络线呈高斯分布的Morlet小波作为小波变换的母小波进行拟合处理,得到光纤与已知折射率的匹配液之间的相对高度。通过计算获得光纤的折射率分布,并对获得的数据采用光纤折射率分布的经典函数进行拟合,得到多模光纤和单模光纤的决定系数分别为0.997 2和0.996 4。最后将实验获得的结果与官方参数进行比较,误差为0.01%,表明该种方法测量的精度较高,完全可以用来测量光纤的折射率。 相似文献