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1.
In this paper, we have proposed and demonstrated a novel packaging method involving a vertical cavity-surface emitting laser (VCSEL) array. The concept is based on micro optical bench (MOB) placing a laser sub-mount and two-dimensional optical fiber array to match the reference plane of MOB to provide an alignment free optical interconnect. No degradation of I-V and I-L characteristics of the packaged VCSELs was found after use of the proposed packaging process. The coupling loss was about 0.9 dB for λ = 1.55 μm and the loss deviation among channels was less than 0.5 dB in a 2 x 4 ch coupling module between planar microlens and multi-mode fibers. 相似文献
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We propose a new concept for an optical network unit using planar microlens array for fiber to the home networks. It is expected from this modeling that an optical coupling loss of 2.5 dB, a polarization dependent loss of 0.5 dB and an extinction ratio larger than 50 dB can be achieved. The structure design and its fabrication method are discussed. 相似文献
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A GaP microlens for collecting laser light was developed in the tip of a near-field probe. It is important to realize a near-field optical probe head with high throughput and a small spot size. The design and fabrication results of the GaP microlens array are described. The most suitable GaP microlens with a probe was calculated as having a 10 μm radius using the two-dimensional finite difference time domain (2-D FDTD) method. The full width half maximum (FWHM) spot size variation and optical power density tolerance were calculated as 157 nm ± 5 nm and 7%, respectively. A spherical GaP microlens was fabricated with a radius of 10 μm by controlling the Cl2/Ar gas mixture ratio. The difference between the theoretical spherical shape and the fabricated GaP microlens was evaluated as 40 nm at peak to valley. The FWHM spot size and optical throughput of the fabricated microlens were measured as 520 nm and 63%, respectively. The microlens was the same as a theoretical lens with a 10 μm radius. The micron-lens array fabrication process for a near-field optical head was demonstrated in this experiment. 相似文献
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It is essential to know the wavelength dispersion of a planar microlens in order to suitably design optical systems which use such a component. For this purpose, the measurement of focal length over a wide range of the spectrum has been performed. It was clarified that the focal length varies by about 20% from blue (ƛ=0.442 μm) to near-infra red (ƛ=1.55μm) region. The maximum index difference between the lens center and substrate, an important parameter for the characterization of planar microlenses, has been estimated as a function of wavelength using the ray equation. The effect of angled incidence has been discussed. 相似文献
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非均匀平板波导的色散方程 总被引:6,自引:6,他引:0
利用转移矩阵理论分析了任意折射率分布平板波导的传输特性,导出了非均匀平板波导的近似解析色散方程,并指出了WKB近似的局限性,数值比较的结果表明,文中所得公式的精确度优于传统的WKB方法和其它近似方法。 相似文献
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为提高变折射率平面微透镜阵列的填充率,利用光刻工艺和离子交换技术制备了填充率近达100%的方形孔径平面微透镜阵列,并对其透镜元及相邻透元间间隙构成的角落区域的成像进行了理论和实验研究.根据变折射率介质光线追迹法,利用MATLAB软件模拟,发现在透镜元区域和角落区域成像特性相反.成像系统测试表明:由于透镜元区域和角落区域的折射率分布变化规律不同,透镜元与角落区域对物体分别成倒立实像和正立虚像;透镜阵列可实现聚焦和散焦功能;角落区域得到充分的离子交换使得间隙足够小,形成了从该区域中心向外逐渐增大的新型梯度折射率模型. 相似文献
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An optical system for learning neural networks with a 2-D architecture was constructed using a Selfoc microlens array. Using this system, we achieved pattern recognition of typed alphabet characters detected directly with a CCD camera. The system learned 4 characters according to a random search algorithm in order to avoid the difficulties and the costs of calculations of learning signals, optical alignments and addressing to the device which display the weight tensors. 相似文献
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Jinjin Jin Xiaohu Zhang Ping Gao Jun Luo Zuojun Zhang Xiong Li Xiaoliang Ma Mingbo Pu Xiangang Luo 《Annalen der Physik》2018,530(2)
Ascribing to the properties of two dimensional parallel focusing and imaging, low propagation loss, integration and miniaturization, microlens array has been widely used in imaging, optical communication, organic light emitting devices, adaptive optics, photolithography, biomedical and other applications. However, the existing traditional microlens array suffers from difficulty in fabrication, large‐thickness, curved surface, non‐uniformity of light spots, or requirement of additional discrete components to control the microlens. Herein, a planar microlens array is experimentally demonstrated based on the geometric metasurface. The single microlens is composed of space‐variant subwavelength metallic gratings with high polarization conversion efficiency and thus exhibits gradient phase distribution. The focused spot diameter of 22.5 μm with radius of 350 μm, focal length of 1 cm and the light spots intensity uniformity of 0.9885 (standard deviation 0.0115) at the focal plane are obtained. Moreover, the broadband property of microlens array is also confirmed. The novel design strategy for microlens array would facilitate the miniaturization of optical devices and be easily integrated in the optical interconnected devices. 相似文献
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H.J. Tiziani R. Achi R.N. Krämer T. Hessler M.T. Gale M. Rossi R.E. Kunz 《Optics & Laser Technology》1997,29(2):85-91
A new; high resolution measuring system based on confocal microscopy has been developed for the evaluation of microlens arrays; in particular for applications in confocal microscopy itself. Lenslet arrays for parallel scanning and processing in confocal microscopy were designed as phase-matched Fresnel lenslets and fabricated by direct laser writing. Replica arrays were produced by ultraviolet embossing and hot embossing techniques. Fabricated arrays with a numerical aperture of 0.28 exhibited near diffraction limited performance and a focal length standard deviation of 120 nm in a nominal value of 250 μm. The technique developed represents a convenient and powerful technique for the characterization of lenslet arrays in general. 相似文献
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凹折射微透镜阵列的离子束刻蚀制作 总被引:1,自引:0,他引:1
利用光刻热熔成形工艺及离子束刻蚀制作 12 8× 12 8元凹微透镜阵列。所制硅及石英凹微透镜的典型基本图形分别为凹球冠形、凹柱形和矩顶凹面形。分析了在光致抗蚀剂柱凹微透镜图形制作过程中的膜系匹配特性 ,与制作该种微透镜有关的光掩模版的主要结构参数 ,以及光致抗蚀剂掩模工艺参数的控制依据等。探讨了在凹微透镜器件制作基础上利用成膜工艺开展平面折射微透镜器件制作的问题。采用扫描电子显微镜 (SEM)和表面轮廓仪测试了所制石英凹微透镜阵列的表面微结构形貌。给出了所制石英凹微透镜阵列远场光学特性的测试结果。 相似文献
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激光直接光刻制作微透镜列阵的方法研究 总被引:2,自引:1,他引:1
介绍了利用激光直接光刻制作8相位台阶菲涅尔衍射微透镜列阵的工艺方法,并对元件的衍射效率及光刻过程中的制作误差进行了分析,透镜列阵在小形Shack-Hartmann波前传感器中得到了应用。 相似文献
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重铬酸铵明胶微透镜阵列的研究 总被引:1,自引:0,他引:1
根据重铬酸铵明胶在受光照后发生交联的原理,采用重铬酸铵明胶作材料制作了微透镜阵列。讨论了制作微透镜阵列的最佳技术条件。提出了已制成的微透镜阵列的一些技术参数。 相似文献
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本文研究超构平面的光-物质相互作用机理。以13 nm Ge/20 nm Al2O3/Ag结构为例,建立色散方程、计算色散关系曲线。研究表明:超构平面支持Brewster共振模式,满足波矢匹配条件时可由从空气中入射的电磁波激发,使共振波长处吸收率接近100%(厚度只有13 nm的Ge薄膜中吸收率超过96%)。还表明:在很宽水平方向波矢量范围内,超构平面TM和TE偏振色散关系曲线近似为水平线,因而具有广角度和偏振不敏感吸收特性(结构对60°入射的两种偏振光的吸收率仍超过90%)。 相似文献
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折射型微透镜列阵的光刻热熔法研究 总被引:8,自引:1,他引:7
研究了制作折射型微透镜列阵的一种新方法光刻胶热熔成形法,获得了20×20的折射型微透镜列阵,单元微透镜相对口径为F/2,单元透镜直径为90μm,中心间隔100μm,透镜的波像差小于1.3波长。本文详细阐述了光刻热熔法的基本原理及微透镜设计方法,并讨论了工艺参数对微透镜列阵质量的影响。 相似文献
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基于模式耦合理论,研究了呈一字型排列的多根平行单模光纤间的功率转移,分析了光纤间距对耦合系数和功率转移的影响,给出了三根平行单模光纤耦合方程的解,针对不同的初始条件进行了比较分析.数值计算表明,呈一字型排列的多根平行单模光纤间的功率成一定周期转移. 相似文献
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The purpose of this investigation is to assess and improve the accuracy of Sauter Mean Diameter measurements in dense sprays using a Planar Droplet Sizing (PDS) technique, based on the intensity ratio of scattered and fluorescence light. A novel data processing method of the PDS technique is suggested, which was derived from a theoretical light scattering investigation, and reduced possible sizing errors larger than 30% to below 10%. The novel approach for droplet sizing was applied to measure in a spray generated by a pressure swirl atomiser in a liquid‐fuelled burner operated with water at isothermal conditions, in order to avoid the effect of liquid evaporation on the accuracy of PDS technique. The Sauter Mean diameter results from the PDS technique were compared to Phase Doppler Anemometer (PDA) sizing measurements. Good agreement was obtained between the two techniques in dense regions of the spray. Discrepancies remained in dilute spray regions due to systematic statistical uncertainties of the PDS technique and the dynamic range of the intensity of the CCD cameras, which did not allow detection of large single droplets in the dilute spray region. 相似文献