共查询到19条相似文献,搜索用时 140 毫秒
1.
2.
提出并分析了利用蜘蛛网结构包层空芯布喇格光纤在0.65 μm~1.55 μm和200 μm ~500 μm波长范围得到低损耗传输的可能性.采用渐近转移矩阵公式所做的分析结果表明:这种光纤的传输损耗远低于构成光纤所用塑料的吸收损耗.在0.65 μm ~1.54 μm的可见至近红外波段,这种光纤结构可把构成光纤所用塑料的吸收损耗抑制为1/237 000,甚至可抑制为1/1 300 000;在200 μm ~500 μm的太赫兹波段,这种光纤结构可把构成光纤所用塑料的吸收损耗抑制为1/8 962,甚至可抑制为1/83 390.因此用便宜的塑料,可以在可见至太赫兹波段用这种光纤构成较长距离、较高带宽的光纤通信系统,并实现波分复用(WDM). 相似文献
3.
多模梯度折射率塑料光纤带宽的分析 总被引:3,自引:3,他引:0
结合WKB法对多模梯度折射率塑料光纤(GI-POF)色散和带宽进行了综合分析,研究了在GI-POF中材料色散对带宽影响的程度和规律,给出较佳折射率指数(g)的范围,并说明实测带宽高于理论带宽的原因. 相似文献
4.
《光子学报》2015,(10)
针对普通石英光纤质地较脆,应用在结构裂缝监测中易发生断裂的现象,本文运用塑料光纤代替普通石英光纤进行结构裂缝监测,并且考虑复合材料裂缝开裂方向的不确定性,对塑料光纤及其裂缝监测能力进行了研究.设计了一套塑料光纤传感装置,并通过裂缝模拟装置来研究塑料光纤分别与裂缝呈30°、45°、60°夹角时,光损耗与裂缝开度的关系.实验结果表明,随着裂缝的开展,光损耗逐渐增加;纤芯直径为0.5mm时最大光损耗幅值为78.76μW,而纤芯直径为0.25 mm时,最大光损耗幅值只有24.28μW,纤芯直径较大的光纤在微弯时易发生较大的光损耗.塑料光纤传感装置在结构裂缝监测中应用是可行性的,而且塑料光纤裂缝传感器的灵敏性随着方位角的增加而降低. 相似文献
5.
阐述了阶跃型塑料光纤和渐变型塑料光纤的发展过程及其国内外研究现状,介绍了塑料光纤在局域网、汽车工业、传感器等领域的应用.通过对石英光纤、金属电缆与塑料光纤的性能进行比较,得到了塑料光纤具有芯径大、柔韧性好、价格低廉、制作简单等特点.就塑料光纤在局域网、汽车工业、传感器等领域的应用进行了分析、总结,结果表明降低塑料光纤的传输损耗可以进一步扩大其应用领域.最后分析了我国塑料光纤的研究、生产现状与国际水平的差距,并提出了提高国产塑料光纤技术水平的建议. 相似文献
6.
7.
低损耗阶跃型塑料光纤(SI-POF)工艺的研究 总被引:4,自引:1,他引:3
介绍一种用高分子材料研制低损耗阶跃型塑料光纤(SI-POF)的新型工艺流程,采用甲基丙烯酸甲酯(MMA)与其他高分子材料共聚合成一种阶跃型折射率分布塑料光纤(SI-POF).该光纤采用含氟树脂包层,可以降低损耗.原料的精馏提纯、聚合反应、拉丝等整个工艺过程都处在一个密闭系统中.探讨聚合反应方式对塑料光纤导光性能的影响,从而获得性能优异的塑料光纤,光纤的使用距离为50~100m,其导光性能为:光损耗小于200dB/km;数值孔径为0.35~0.55. 相似文献
8.
9.
10.
11.
We explore the dependence of power losses on average plastic energy densities as rays propagate along deformed polymer optical fibers (POFs). The variation of power losses in deformed POFs with different bend radii and elongations are measured and analyzed. Three-dimensional elastic-plastic finite-element models are used to calculate average plastic energy densities in deformed POFs. The results indicate that the average plastic energy density introduced in a deformed POF can be considered a key index with which to study the power loss. Based on the experimental results, a curve-fitted equation is proposed for estimating the power loss by using the average plastic energy density for various bend radii. 相似文献
12.
13.
Jian-Ji Huang Hone-Ene Hwang Chun-Yuan Chen Ching-Mu Chen 《Optics & Laser Technology》2012,44(7):2238-2244
A novel method of the optical multiple-image encryption based on the modified Gerchberg–Saxton algorithm (MGSA) is presented. This proposed method with an architecture of two adjacent phase only functions (POFs) in the Fresnel transform (FrT) domain that can extremely increase capacity of system for completely avoiding the crosstalk between the decrypted images. Each encrypted target image is separately encoded into a POF by using the MGSA which is with constraining the encrypted target image. Each created POF is then added to a prescribed fixed POF composed of a proposed MGSA-based phase encoding algorithm. Not only the wavelength and multiple-position parameters in the FrT domain as keys to increase system security, the created POFs are also served mutually as the encryption keys to decrypt target image based on cascading two POFs scheme. Compared with prior methods [23], [24], the main advantages of this proposed encryption system is that it does not need any transformative lenses and that makes it very efficient and easy to implement optically. Simulation results show that this proposed encryption system can successfully achieve the multiple-image encryption with multiple-position keys, which is more advantageous in security than previous work [24] for its decryption process with only two POFs keys to accomplish this task. 相似文献
14.
15.
The attenuation and dispersion of commercially available all-plastic step-index optical fiber are the major factors limiting the maximum achievable transmission distance and bit rate; this article explores these limits. Calculations predict that ∼ 500 Mb/s transmission over 100 m of standard 0.47 NA step-index PMMA POF at 650 nm is feasible, and recent experimental results at up to 400 Mb/s are briefly described. The implications of having a lower loss, higher bandwidth POF, for example, perfluorinated, graded-index PMMA, arc discussed. 相似文献
16.
Abstract The attenuation and dispersion of commercially available all-plastic step-index optical fiber are the major factors limiting the maximum achievable transmission distance and bit rate; this article explores these limits. Calculations predict that ~ 500 Mb/s transmission over 100 m of standard 0.47 NA step-index PMMA POF at 650 nm is feasible, and recent experimental results at up to 400 Mb/s are briefly described. The implications of having a lower loss, higher bandwidth POF, for example, perfluorinated, graded-index PMMA, arc discussed. 相似文献
17.
We theoretically demonstrate that microscopic heterogeneous properties can enhance the transmission bandwidths of graded-index plastic optical fibers (POFs) for short-haul communication networks. The heterogeneities of the POF cores are quantitatively correlated with mode couplings by modifying the coupled power equation with consideration of the spatial correlation characteristics of the heterogeneities. Using the modified theory, we clarify that the larger fluctuation size and/or amplitude results in higher bandwidth because of greater forward scattering and/or higher scattering efficiency, respectively. This suggests that the multimode fiber bandwidths can depend on the macroscopically observed index profiles as well as on the microscopic material properties. 相似文献
18.
The combined effects of bending and elongation on fiber losses as rays propagate along deformed polymer optical fibers (POFs) are investigated. The variations in power attenuation for various curvature radii and elongations are studied. The experimental results indicate that the combination of bending and elongation significantly affects the power loss of POF. From the results an equation is proposed to predict the power losses for different bent radii and elongations. The maximum difference between the proposed equation and the experimental results is less than 5%. 相似文献