Very small single-mode ten-fiber connector

A small plastic molded single-mode ten-fiber connector has been developed for high-count optical subscriber cables. The connector ferrule alignment mechanism is designed with a sufficient factor of safety to allow rough handling during connection. The ferrules are precisely aligned by alignment pins and guide sleeve. The fabricated connector, which has a cross section of just 4 mm × 6 mm, exhibited an average loss of 0.4 dB and reconnection time of less than 0.5 min. Connection loss does not change after over 1000 reconnections     

High-strength glass-ceramic ferrule for SC-type single-mode optical fiber connector

A high-strength Li/sub 2/O-Al/sub 2/O/sub 3/-SiO/sub 2/ glass-ceramic ferrule has been realized by using a precise glass-ceramic drawing technique which was developed to reduce production costs. With the ion-exchange process that applies the residual compressive stress to the surface layer, the bending strength of the ferrule reached about 500 MPa, which is similar to that of an alumina ferrule. It maintained a bending strength of 310 MPa after scratching. The Young's modulus and micro Vickers hardness are similar to those of silica-glass optical fiber. The linear expansion coefficient is far smaller than that of zirconia. These characteristics suggest the stable physical contact and the easy endface polishing as the optical connector.     

一种陶瓷插芯内光纤断点的检测方法

提出了一种通过白光干涉仪来检测陶瓷插芯中光纤是否存在断点的方法。通过使用白光干涉仪使陶瓷端面和插芯内光纤断点处两个表面的反射光分别与扫描臂上反射镜的反射光发生干涉,然后,根据两条干涉条纹的强度和间距,便可检测出陶瓷插芯内是否有光纤断点以及陶瓷插芯内断点离光纤连接头端面的位置。试验结果表明,该方法的测量灵敏度可达0.03mm。此方法非常适用于检测生产和使用过程中的光纤/光缆连接器陶瓷插芯中的光纤是否存在断点,并进行精确的分析,保证连接器的质量及可靠性,具有准确性高、操作简单的特点。     

Design and performance of a modular jack type Mini-MT connector forhigh-density optical duplex connection

We have developed a modular jack type Mini-MT that employs a compact two-fiber ferrule in a housing. The connector mechanism is similar to that of a conventional electric modular jack type connector. The connector also has a locking mechanism to prevent accidental disconnection and a high packaging density of 2 fibers/cm². Fabricated connectors for single-mode two-fiber ribbons exhibit a low insertion loss of 0.17 dB and a high return loss of more than 40 dB     

Improved design of APC optical connectors with slanted angle of12° for dispersion shifted optical fiber

This paper describes improved design criteria for a highly stable angled physical contact (APC) connector with a slanted angle of 12° for a dispersion shifted optical fiber, which is derived from the theoretical considerations based on experiments. A shift of the vertex point of the convex ferrule endface from the optical fiber axis is minimized, so that compatibility among APC connectors can be established by using a new type of stepped-ferrule developed by the author. When rotation angle between the mating ferrules was less than 4° in a circular direction, the insertion losses for the improved APC connectors consisting of stepped-ferrules were 0.23±0.45 dB, while the insertion losses for the conventional APC connectors consisting of tapered-ferrules measured 0.39±0.89 dB. It can be confirmed that slanted angle of the convex ferrule endface is required to be 12° to obtain a backreflection of less than -60 dB for the dispersion shifted optical fiber at the wavelength of 1.550 μm     

Super-multi-fibre PLC connector utilising angled connection between PLC and tens of fibres

A novel super-multi-fibre planar lightwave circuit (PLC) connector, designed to connect tens of optical fibres and a PLC for super-multichannel PLC-based optical modules with a receptacle interface, is proposed. This connector employs an angled connection instead of a PC connection. A 0.127 mm pitch 32-fibre connector is also demonstrated, which exhibits low connection and high return losses.     

Design and performance of an angled physical contact typemultifiber connector

An angled, physical contact type multifiber connector is developed on the basis of a structural design which enables direct fiber endface contact between multifiber arrays. The direct contact is achieved by utilizing the elastic nature of a ferrule material under compressive force. The fabricated connector provides a low insertion loss of 0.2 dB and a high return loss of 58.8 dB without index-matching. This connector is used in the successful development of push-on type and backpanel type 16-fiber connectors with a low insertion loss of 0.25 dB and a high return loss of 58.0 dB for future subscriber networks     

Optical fiber design for field mountable connectors

This paper presents a study on optical fiber and connector ferrule assembly design optimization aimed at minimizing modal interference in field-mountable single-mode fiber connectors that utilize a ferrule mounted short fiber stubs and integrated splices. A theoretical model for analyzing the modal interference is proposed and verified experimentally. It is shown that modal interference can be reduced by optimizing both the fiber design and its surrounding material     

Characteristics of fibre-optic connector at high-power opticalincidence

The high-power characteristics of the MU-type fibre-optic connector are investigated systematically for the first time. It is clarified that a connector with a low insertion loss of below 0.25 dB suppressed the undesirable temperature increase to less than 10° with an optical input of 1 W, and appropriate ferrule endface cleaning prevented endface damage     

Low-Loss Intermatability Between Ferrule Pretuned Connector and 90 Degree Tuned Connector: Statistical and Experimental Study

Random intermate connector insertion loss performance between IEC international standardized single fiber connectors with 90 degree tuned [hereafter, called, "90 degrees Tuned connector (90DTC)] and newly proposed connectors with pretuned ferrules and randomly inserted fibers [hereafter, ferrule tuned fiber random connector (FTFRC)] were evaluated by a Monte Carlo simulation and compared with experimental results. The Monte Carlo simulation yielded the following theoretical results: 0.03 dB mean for the 90DTC, 0.03 dB mean for the FTFRC, and 0.03 dB mean for connection losses between the 90DTC and FTFRC. The experimental results yielded excellent agreement for the 90DTC intermate and FTFRC intermate. The experimental mean connection losses between 90DTC and FTFRC connectors were slightly higher than the simulation with a mean of 0.05 dB.     

光纤连接器插针体端面的超声波研磨

探讨了在普通研磨的基础上引入超声波的复合研磨方式,将普通研磨和引入超声波后研磨的效果进行了对比,并对超声波复合研磨的机理进行了简单的分析。     

Novel field installable optical fiber splice and connector for optical access networks

We have developed two types of field installable connection techniques. One is mechanical splicing, which is used to connect coated optical fibers without the need for stripping or cleaning procedures. The other is a field assembly connection technique, which employs a new type of field installable connector that makes it possible to realize a physical contact connection with chamfer grinding. Mechanical splicing is achieved by precisely aligning and directly connecting coated fibers with a capillary. The assembled splice is installed with 1.3-μm single-mode fibers that have an 80-μm cladding and a 125-μm coating and they exhibit good optical performance with a low average insertion loss of 0.2 dB. Connection is achieved with our developed field installable connector by using a chamfered fiber endface and the compression force of the buckled fiber. The assembled connectors achieve physical contact with the chamfered fiber endface, which provides good optical performance with a low insertion loss of 0.11 dB.     

Displacement Measurements at a Connector Contact Interface Employing a Novel Thick Film Sensor

One of the key failure mechanisms for wiring and connector systems used in the automotive industry, is fretting and fretting corrosion at the contact interface of connectors. For many years, procedures have been carried out under laboratory controlled conditions to investigate both thermal and vibration fretting effects using environmental chambers and fretting tests. Both optical and visual inspections have also been adopted to observe the movement at the contact interface. However, these methods can be considerably inconvenient and costly. Furthermore, their suitability for field applications is limited. In order to study the fretting degradation at the actual interface for in-situ measurement effectively, a novel position sensor is designed to monitor the relative displacement. Thick film techniques are employed to fabricate miniaturized and cost effective resistive devices. The sensor is assembled into a connector sample by taking the place of the male component. When the interface experiences movement, the relative displacement of the contact point would cause a corresponding linear change of resistance measured across the male and female connection. The sensors are validated by a series of experiments and subsequently used in a field test to establish the relationships between the fretting effects with temperature, humidity and differential pressure, which is associated with temperature variation.      

Present Status of Mechanical Connectors for Optical Fiber

Trunk transmission network systems connecting exchange offices were the first transmission systems using optical fiber cables. Subscriber network systems connecting the exchange office with each subscriber including local area networks or CATV network systems are under development at present. Two main techniques are newly required to be developed for making optical fiber mechanical connectors for optical fiber subscriber network system realization. The first is to realize a new connector with a high return loss and a low connecting loss. The second is to cut the joining cost of optical fibers. The newly developed "optical contact connector" realized a high return loss of more than 25 dB and a low connecting loss of 0.15 dB average value. A newly developed "multifiber connector" which can connect many optical fibers at the same time can save time and space for joining fiber cables, and also a "plastic molding technique" can save the cost of the connector. The performance of all these connectors is the same as that of the "optical contact connector." This paper describes the present status of the technique to obtain a high return loss connector, a multifiber connector, and a plastic molded connector for the subscriber network system.     

A compact optical active connector: an optical interconnect modulewith an electrical connector interface

This paper describes a compact optical active connector that has both optical and electrical interfaces for an asynchronous-transfer-mode (ATM) switching system and high-speed computer network systems. This connector with an O/E or E/O conversion module can replace the conventional electrical-cable six-pin connector for an ordinary printed circuit board that has only an electrical interface. Our connector consists of a specially developed duplex MU-type submodule with photonic devices, an electrical connector, and integrated circuits (ICs). It can be used for 620-Mbps data transmission and has lower electromagnetic radiation noise than conventional connectors. Using optical active connectors to replace electrical-cable connectors will facilitate the introduction of high-throughput, large-capacity ATM switching systems, and next-generation local area network systems     

Temperature, humidity and pressure measurement on automotive connectors

Environmental testing under laboratory-controlled conditions has long been used to evaluate connector performance prior to practical application. There are a number of experimental procedures frequently used in the automotive industry such as the USCAR standard for automotive electrical connector systems to test connectors. However, recent research has shown that these tests appear to evaluate the mechanical stability of the connector housings and terminals, rather than their electrical performance. In order to establish more representative tests to evaluate the electrical performance of contacts, the actual environmental conditions at the contact interface, which are generally unknown, must be measured. This paper compares the temperature, humidity, and air pressure inside the connector housing to those measured outside. It was found that the conditions inside and outside the connector housing are different and a model relating the conditions is introduced.     

Study of surface mounting of PLC on optical fibre circuit board

The first surface mounting of a planar lightwave circuit (PLC) on an optical fibre circuit board is proposed and demonstrated. Both surface mounting and physical contact connection between a PLC type duplex 1×16 splitter and fibres were realised     

Elimination of self-contamination in high-density low-loss single-mode fiber array connectors

We report quantitative measurements of self-contamination in conventional and modified multi-SMF mechanically transferable (MT) connector ferrules. The modifications enable connector wear, insertion loss (IL), and IL reproducibility that are essentially equivalent to conventional ceramic ferrule connectors.     

大破断力系留接头连接技术的探讨

通过对系留气球主缆绳与系留接头连接技术的系统研究和分析,提出了大破断力系留接头连接方式的设计依据,突破了传统系留接头的制造技术瓶颈。针对传统楔形夹紧连接技术的缺点,设计了采用环氧树脂胶粘接纤维制作的系留接头,其破断力300kN,具有高可靠性和较强工程应用性。     

Generating mechanism of maintaining force for optical fiberinstalled in ferrule hole

This paper describes a new theory of the maintaining force to keep the optical fiber in the ferrule hole, based on the theoretical analysis assuming the dimensional change among the ferrule, optical fiber, and epoxy adhesive layer, since the maintaining force is caused by the difference of linear expansion coefficients among those elements when temperature is changed. The major maintaining force for the optical fiber installed in the ferrule hole is caused by the radial compressive force applied to the cured epoxy adhesive layer, which caused by dimensional shrinking of the clearance between the optical fiber and the ferrule hole, due to a large amount of shrinkage in the ferrule and a small amount of shrinkage in the optical fiber when the temperature changes