1、 TIA-455-54-B-1998 APPROVED: JUNE 24, 1998 REAFFIRMED: DECEMBER 26, 2001 REAFFIRMED: FEBRUARY 6, 2013 TIA-455-54-B (Revision of TIA-455-54-A) August 1998FOTP- 54-B Mode Scrambler Requirements for Overfilled Launching Conditions to Multimode Fibers NOTICE TIA Engineering Standards and Publications ar
2、e designed to serve the public interest through eliminating misunderstandings between manufacturers and purchasers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for their particular need. The
3、 existence of such Standards and Publications shall not in any respect preclude any member or non-member of TIA from manufacturing or selling products not conforming to such Standards and Publications. Neither shall the existence of such Standards and Publications preclude their voluntary use by Non
4、-TIA members, either domestically or internationally. Standards and Publications are adopted by TIA in accordance with the American National Standards Institute (ANSI) patent policy. By such action, TIA does not assume any liability to any patent owner, nor does it assume any obligation whatever to
5、parties adopting the Standard or Publication. This Standard does not purport to address all safety problems associated with its use or all applicable regulatory requirements. It is the responsibility of the user of this Standard to establish appropriate safety and health practices and to determine t
6、he applicability of regulatory limitations before its use. (From Project No. 3-3149-RV2-RF2, formulated under the cognizance of the TIA TR-42 Telecommunications Cabling Systems, TR-42.12 Subcommittee on Optical Fibers and Cables). Published by TELECOMMUNICATIONS INDUSTRY ASSOCIATION Technology (b) t
7、here is no assurance that the Document will be approved by any Committee of TIA or any other body in its present or any other form; (c) the Document may be amended, modified or changed in the standards development or any editing process. The use or practice of contents of this Document may involve t
8、he use of intellectual property rights (“IPR”), including pending or issued patents, or copyrights, owned by one or more parties. TIA makes no search or investigation for IPR. When IPR consisting of patents and published pending patent applications are claimed and called to TIAs attention, a stateme
9、nt from the holder thereof is requested, all in accordance with the Manual. TIA takes no position with reference to, and disclaims any obligation to investigate or inquire into, the scope or validity of any claims of IPR. TIA will neither be a party to discussions of any licensing terms or condition
10、s, which are instead left to the parties involved, nor will TIA opine or judge whether proposed licensing terms or conditions are reasonable or non-discriminatory. TIA does not warrant or represent that procedures or practices suggested or provided in the Manual have been complied with as respects t
11、he Document or its contents. If the Document contains one or more Normative References to a document published by another organization (“other SSO”) engaged in the formulation, development or publication of standards (whether designated as a standard, specification, recommendation or otherwise), whe
12、ther such reference consists of mandatory, alternate or optional elements (as defined in the TIA Engineering Manual, 4thedition) then (i) TIA disclaims any duty or obligation to search or investigate the records of any other SSO for IPR or letters of assurance relating to any such Normative Referenc
13、e; (ii) TIAs policy of encouragement of voluntary disclosure (see Engineering Manual Section 6.5.1) of Essential Patent(s) and published pending patent applications shall apply; and (iii) Information as to claims of IPR in the records or publications of the other SSO shall not constitute identificat
14、ion to TIA of a claim of Essential Patent(s) or published pending patent applications. TIA does not enforce or monitor compliance with the contents of the Document. TIA does not certify, inspect, test or otherwise investigate products, designs or services or any claims of compliance with the content
15、s of the Document. ALL WARRANTIES, EXPRESS OR IMPLIED, ARE DISCLAIMED, INCLUDING WITHOUT LIMITATION, ANY AND ALL WARRANTIES CONCERNING THE ACCURACY OF THE CONTENTS, ITS FITNESS OR APPROPRIATENESS FOR A PARTICULAR PURPOSE OR USE, ITS MERCHANTABILITY AND ITS NONINFRINGEMENT OF ANY THIRD PARTYS INTELLE
16、CTUAL PROPERTY RIGHTS. TIA EXPRESSLY DISCLAIMS ANY AND ALL RESPONSIBILITIES FOR THE ACCURACY OF THE CONTENTS AND MAKES NO REPRESENTATIONS OR WARRANTIES REGARDING THE CONTENTS COMPLIANCE WITH ANY APPLICABLE STATUTE, RULE OR REGULATION, OR THE SAFETY OR HEALTH EFFECTS OF THE CONTENTS OR ANY PRODUCT OR
17、 SERVICE REFERRED TO IN THE DOCUMENT OR PRODUCED OR RENDERED TO COMPLY WITH THE CONTENTS. TIA SHALL NOT BE LIABLE FOR ANY AND ALL DAMAGES, DIRECT OR INDIRECT, ARISING FROM OR RELATING TO ANY USE OF THE CONTENTS CONTAINED HEREIN, INCLUDING WITHOUT LIMITATION ANY AND ALL INDIRECT, SPECIAL, INCIDENTAL
18、OR CONSEQUENTIAL DAMAGES (INCLUDING DAMAGES FOR LOSS OF BUSINESS, LOSS OF PROFITS, LITIGATION, OR THE LIKE), WHETHER BASED UPON BREACH OF CONTRACT, BREACH OF WARRANTY, TORT (INCLUDING NEGLIGENCE), PRODUCT LIABILITY OR OTHERWISE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. THE FOREGOING NEGAT
19、ION OF DAMAGES IS A FUNDAMENTAL ELEMENT OF THE USE OF THE CONTENTS HEREOF, AND THESE CONTENTS WOULD NOT BE PUBLISHED BY TIA WITHOUT SUCH LIMITATIONS. STD-EIA TIA-q55-54B-ENGL 1998 m 3234bO8 Ob137Lb 251 m TI A/EI A-45 5 - 5 48 FOTP-54 Mode scrambler requirements for overfilled launching conditions to
20、 multimode fibers Contents Foreword . 1 2 3 4 5 6 7 8 introduction . . Normative references . . Apparatus . . . . . . . . . . . . . . . Sampling and Specimens . . . . . . . . Procedure . . . . . . . . . . . . Calculations or interpretation of results . . . . . . . . . . . . . . . . . . . . . . . . .
21、 . . . . . . . . . . . . . . . . . . . . . . . Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Specification information . . . . . . iii 1 1 2 4 4 7 7 8 Annex A - F
22、abrication of mode scramblers to the step-graded-step design, patent considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 O Annex B - Literature references . . . . . . . . . . 1 1 Annex C - Comparison between FOTP-54 and IEC or ITU-T requirements . . . . . . . .
23、 . . 1 2 i STD-EIA TIA-455-548-ENGL 1778 I323LibCICI Oh13717 198 I TIA/EIA-45 5-548 FOTP-54 Mode scrambler requirements for overfilled launching conditions to multimode fibers Foreword (This Foreword is informative only and is not part of this Standard.) . This document comes from EIA Standards Prop
24、osal No. 1787-C and was formulated under the cognizance of TIA FO-6.6 Subcommittee on Optical Fibers and Materials. This FOTP is part of the series of test procedures included within Recommended Standard EIATTIA-455. NOTE: This FOTP was previously published in Recommended Standard RS-455-5 as FOTP-5
25、 4A. There are three annexes. One is normative, and the other two are informative. Key Words: bandwidth, mode scrambler, optical fiber, launching conditions iii STD-EIA TIA-q55-5qB-ENGL 1978 I3234b00 Ob13718 02Li 9 Tl A/EIA-45 5-548 1 Introduction This procedure describes light launch conditions to
26、the test fiber for the purpose of achieving a uniform overfilled launch with a laser diode or other light sources. While FOTP-54 can be used to establish overfilled launching conditions fr the measurement of various fiber parameters, it is principally used in conjunction with FOTP-30 or FOTP-5 1 for
27、 measuring information carrying capacity. Light launch conditions are established through the use of a mode scrambler. The mode scrambler is positioned between the light source and test fiber to produce a radiation distribution overfilling the test fiber core and numerical aperture, irrespective of
28、the spatial radiation properties of the light source. For many mode scrambler designs, however, the launching conditions produced depend on the source/mode scrambler alignment and the interaction with any intermediary optics such as connectors or optical imaging systems. If the source or any compone
29、nt in the optical system is changed, the qualification tests must be repeated. When applied to information transmission capacity measurements, the overfilled launch gives good measurement reproducibility; it is not intended to necessarily give the best bandwidth prediction for concatenated lengths.
30、Also, a particular light source/mode scrambler combination may be satisfactory for one size core diameter and numerical aperture test fiber, but not for another. _ 2 Normative references Test or inspection requirements may include, but are not limited to, the following references: FOTP-30 (EIATTIA-4
31、55-30B) Frequency Domain Measurement of Multimode Optical Fiber Information Transmission Capacity 1 TIA/EIA-45 5-548 FOTP-43 (EIA-455-43) Output Near- Field Radia tion Pattern Measurement of Optical Waveguide Fiber FOTP-47 (EIATTIA-45 5-478) O u tp ut Far- Field Ra dia tio n Pa t t ern Measurement F
32、OTP-51 (EIATTIA-455-51 A) Pulse Distortion Measurement of Multimode Glass Op tical Fiber Information Transmission Capacity FOTP-58 (EIATTIA-455-58A) Core Diameter Measurement of Graded-Index Optical Fibers . FOTP-177 (TIA/EIA-455-177A) NumericalAperture Measurement of Graded- index Optical Fibers 3
33、Apparatus 3.1 Light Source Use a light source such as a laser diode. FOTPs which reference FOTP-54 may place further requirements on the light source. If FOTP-54 is used for information transmission capacity measurements, use a light source as described in FOTP-30 or FOTP-51. 3.2 Mode scrambler 3.2.
34、1 Definition A “mode scrambler” is a device which is positioned between the light source and test fiber to control launching conditions. A particular mode scrambler design is not specified; however, examples of successful mode scramblers consisting of an optical 2 TIA/EIA-45 5-54B fiber or fibers wi
35、th associated optics are given in Figure 1. It should be emphasized that the performance of these scramblers depends upon the launch optics and fiber sizes (core and NA) used in the actual construction. 3.2.2 Mode scrambler examples Two designs are given for illustration purposes only. Other designs
36、 may perform as well. 3.2.2.1 Step-Graded-Step The mode scrambler in Figure l(a) is a series combination of 1 m lengths of step, graded, and step index fibers spliced together. See references B1 and B2 of Annex B for information concerning fabrication of mode scramblers according to the step- graded
37、-step design. 3.2.2.2 Step with bends The mode scrambler in Figure l(b utilizes a single length of step index fiber. See references B3 and 84 of Annex B for further information concerning the fabrication of step-index fiber mode scramblers. In some instances macroscopic, serpentine bends or wrapping
38、 several turns of the step-index fiber around a mandrel will make the mode scrambler less sensitive to the laser diode alignment. 3.3 Test apparatus to qualify mode scrambler To qualify the mode scrambler, it is necessary to measure near- and far-field radiation patterns of the output of the mode sc
39、rambler when coupled to the light source of 3.1. Appropriate test apparatus is described in FOTP-43 and FOTP-47. If the qualification tests are performed on an image of the mode scrambler output, the appropriate test apparatus may differ from that described in FOTP-43 and FOTP-47. 3.4 Micro position
40、 in g d evice/o p tics Apparatus to couple light from the mode scrambler to the test fiber is needed. This may be a micropositioner along with optics to image the mode scrambler output to the input end of the test fiber. Alternatively, a temporary splice to butt-couple the mode scrambler output to t
41、he input end of the test fiber may be employed. 3 TIA/EIA-45 5-54B 3.5 Cladding mode strippers If the mode scrambler is used in applications where fiber attenuation is measured, apply a cladding mode stripper to the test fiber unless the fiber buffer coating is sufficient to strip cladding light. 4
42、Sampling and specimens The test sample includes the optical source and mode scrambler device. Also included are positioning devices, associated optics such as connectors and optical imaging systems, and fiber to be used in the measurement system. _ 5 Procedure 5.1 Qualification of mode scrambler The
43、 mode scrambler, regardless of design, shall be sufficient to reliably reproduce the launching conditions of 5.1.1 and 5.1.2 and 5.1.3 to the test fiber. If the launching conditions to the test fiber remain stable enough to meet the required launching conditions for all subsequent measurements, the
44、qualification tests need not be made in situ and shall not be required for every test using the mode scrambier. Such stability may be obtained, for example, by permanently pigtaiiing or permanently connectorizing the source to the mode scrambler. For many mode scrambler designs, however, the launchi
45、ng conditions produced depend on the source/mode scrambier alignment and interaction with any intermediary optics such as connectors or optical imaging systems. If the source or any component in the optical system is changed, the qualification tests shall be repeated. 5.1.1 Launch spot on test fiber
46、 With the light source coupled to the mode scrambler fiber, the near-field radiation pattern which excites the test fiber core shall vary by less than 25% across the test 4 STD-EIA TIA-Y55-5qB-ENGL 1778 I3234b00 ObL3722 555 W TIA/ElA-455-546 fiber core area. If the core diameter of the test fiber is
47、 not known, it shall be determined by FOTP-58. If the mode scrambler is connected directly to the test fiber, the near-field radiation pattern which excites the test fiber core shall be measured in accordance with FOTP-43. If the mode scrambler output is optically imaged onto the test fiber input, t
48、he launched near-field distribution shall be determined and referenced to a near-field defined by FOTP-43. 5.1.2 Launch radiation angle to test fiber With the light source coupled to the mode scrambler fiber, the angular intensity distribution which excites the test fiber shall be measured. The laun
49、ch numerical aperture, defined as the sine of the half-angle at which the launched angular intensity has decreased to 5 percent of the maximum value, shall exceed the 5 percent numerical aperture of the test fiber. If the 5 percent numerical aperture of the test fiber is not known, it shall be determined by one of the procedures of FOTP-177. If the mode scrambler is connected directly to the test fiber, the angular intensity distribution from the mode scrambler fiber which excites the test fiber core shall be measured in accordance with FOTP-47. If the mode scrambler out
