BS ISO 20351-2017 Fine ceramics (advanced ceramics advanced technical ceramics) Absolute measurement of internal quantum efficiency of phosphors for white light emitting diodes usi.pdf

1、Fine ceramics (advanced ceramics, advanced technical ceramics) Absolute measurement of internal quantum efficiency of phosphors for white light emitting diodes using an integrating sphereBS ISO 20351:2017BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06 ISO 2017Fine c

2、eramics (advanced ceramics, advanced technical ceramics) Absolute measurement of internal quantum efficiency of phosphors for white light emitting diodes using an integrating sphereCramiques fines (cramiques avances, cramiques techniques avances) Mesurage absolu du rendement quantique interne des lu

3、minophores des diodes lectroluminescentes blanches en utilisant une sphre intgranteINTERNATIONAL STANDARDISO20351First edition2017-09Reference numberISO 20351:2017(E)National forewordThis British Standard is the UK implementation of ISO 20351:2017.The UK participation in its preparation was entruste

4、d to Technical Committee RPI/13, Advanced technical ceramics.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. T

5、he British Standards Institution 2017 Published by BSI Standards Limited 2017ISBN 978 0 580 93286 1ICS 81.060.30Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 3

6、0 September 2017.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS ISO 20351:2017 ISO 2017Fine ceramics (advanced ceramics, advanced technical ceramics) Absolute measurement of internal quantum efficiency of phosphors for white light emitting diodes using an integrat

7、ing sphereCramiques fines (cramiques avances, cramiques techniques avances) Mesurage absolu du rendement quantique interne des luminophores des diodes lectroluminescentes blanches en utilisant une sphre intgranteINTERNATIONAL STANDARDISO20351First edition2017-09Reference numberISO 20351:2017(E)BS IS

8、O 20351:2017ISO 20351:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, inclu

9、ding photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel.

10、+41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 20351:2017ISO 20351:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized ot

11、herwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright offic

12、eCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgISO 20351:2017(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 Measuring equipment . 24.1 Equipment configuration . 24.2 Light

13、 source unit 34.3 Sample unit 34.3.1 Cell 34.3.2 White diffuser or reference cell 44.3.3 Integrating sphere 44.4 Detecting unit . 44.4.1 Directing optics . 44.4.2 Spectrometer and detector . 44.4.3 Amplifier . 44.5 Signal and data processing unit 45 Calibration, checking and maintenance of measuring

14、 equipment 55.1 General . 55.2 Wavelength calibration of light source unit . 55.3 Cells and cover glasses . 55.4 Integrating sphere walls and white diffusers . 55.5 Wavelength calibration of detecting unit . 55.6 Spectral responsivity correction 56 Samples 56.1 Storage and pre-processing . 56.2 Fill

15、ing cells with samples . 57 Measurement methods 67.1 Measurement environment 67.2 Light spectrum without phosphor sample . 67.3 Light spectrum with phosphor sample 68 Calculations 68.1 Conversion to photon-number-based spectra . 68.2 Photoluminescence spectrum 78.2.1 General 78.2.2 Method 1 . 78.2.3

16、 Method 2 . 78.3 Internal quantum efficiency 78.3.1 Relative number of absorbed photons 78.3.2 Relative number of photoluminescent photons 88.3.3 Internal quantum efficiency . 89 Report 8Bibliography .10 ISO 2017 All rights reserved iiiContents PageBS ISO 20351:2017ISO 20351:2017(E)ForewordISO (the

17、International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee

18、 has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnic

19、al standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in

20、accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. De

21、tails of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an

22、endorsement.For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the follo

23、wing URL: www.iso.org/iso/foreword.html.This document was prepared by Technical Committee ISO/TC 206, Fine ceramics.iv ISO 2017 All rights reservedBS ISO 20351:2017ISO 20351:2017(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies

24、 (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations,

25、governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further mai

26、ntenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Att

27、ention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introducti

28、on and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the voluntary nature of standards, the meaning of ISO specific terms

29、 and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.This document was prepared by Technical Committee ISO/TC 206,

30、Fine ceramics.iv ISO 2017 All rights reserved ISO 20351:2017(E)IntroductionWhite light-emitting diode (LED) based solid-state lighting (SSL) has been widely used for a variety of applications as alternatives for incandescent and fluorescent lamps. In the beginning, white LEDs (comprising blue LEDs a

31、nd yellow phosphors) became popular as backlight sources for small-size liquid-crystal displays (LCDs) used in mobile phones and digital cameras. These were followed by white LEDs (consisting of blue LEDs combined with green and red phosphors) applied to backlight sources for large-area LCDs. Subseq

32、uently, LED lamps have been commercialized for general lighting, replacing conventional luminaires and capitalizing on their advantages, such as compactness, high luminous efficiency, high brightness below 0 C or higher ambient temperatures, long life, and controllability of light intensity and colo

33、ur temperature.The optical performance of a phosphor for use in a white LED is one of the most important factors influencing the performance of the white LED. Accordingly, it is of great importance, not only for researchers and manufacturers of phosphors for use in white LEDs but also for researcher

34、s and manufacturers of white LED devices, to evaluate the optical properties of the phosphors in a well-established manner. However, standard measurement methods of studying the optical properties of luminescent powder materials commercially used for white LEDs have never been developed.Photolumines

35、cence quantum efficiency is one of the key parameters of phosphors for use in white LEDs and has been measured extensively by using an integrating sphere-based absolute method. This method was originally developed to determine the photoluminescence quantum efficiency for fluorophore-doped organic th

36、in films and solutions, and has also been applied to phosphor powders. However, those who measure the quantum efficiency of phosphor materials have frequently noted that the measured quantum efficiency may deviate beyond their tolerance level, depending on the measurement equipment, the geometrical

37、configuration of the integrating sphere and the arrangement of the sample cell, even if the measurement procedure is common in principle. This document provides the absolute measurement method of internal quantum efficiency of phosphors for use in white LEDs with reduced deviation of measured values

38、. In this document, measurement equipment and procedures, which can be the sources of the deviation, are described in detail, helping those who address the high performance phosphors for competitive SSL products to obtain the proper information on their competitiveness. ISO 2017 All rights reserved

39、vBS ISO 20351:2017Fine ceramics (advanced ceramics, advanced technical ceramics) Absolute measurement of internal quantum efficiency of phosphors for white light emitting diodes using an integrating sphere1 ScopeThis document specifies a method of absolute measurement (using an integrating sphere) o

40、f internal quantum efficiency of phosphor powders which are excited by UV or blue light and emit visible light, and which are used for white light-emitting diodes (LEDs).This document can be adopted for the measurement of phosphors used in non-white LEDs, for example, green, orange, pink or purple L

41、EDs.2 Normative referencesThe following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (includ

42、ing any amendments) applies.CIE S 017/E:2011, International Lighting Vocabulary3 Terms and definitionsFor the purposes of this document, the terms and definitions given in CIE S 017/ E :2011 and the following apply.ISO and IEC maintain terminological databases for use in standardization at the follo

43、wing addresses: ISO Online browsing platform: available at http:/www.iso.org/obp IEC Electropedia: available at http:/www.electropedia.org/3.1internal quantum efficiencyratio of the number of photons emitted in free space from the phosphor to the number of excitation light photons absorbed by the ph

44、osphor3.2cellcontainer filled with a sample or a white material such as barium sulfateNote 1 to entry: A cell is typically a flat plate sample holder with a cylindrical hollow, a Petri dish or a rectangular cell used in a spectrophotometer.3.3reference cellcell (3.2) filled with a white powder which

45、 has a high spectral diffuse reflectance over the whole visible spectrum (such as barium sulfate or alumina), used when measuring the excitation light spectrum3.4white diffuserwhite plate which has a high spectral diffuse reflectance over the whole visible spectrum such as barium sulfate or polytetr

46、afluoroethylene (PTFE), used when measuring the excitation light spectrumINTERNATIONAL STANDARD ISO 20351:2017(E) ISO 2017 All rights reserved 1BS ISO 20351:2017Fine ceramics (advanced ceramics, advanced technical ceramics) Absolute measurement of internal quantum efficiency of phosphors for white l

47、ight emitting diodes using an integrating sphere1 ScopeThis document specifies a method of absolute measurement (using an integrating sphere) of internal quantum efficiency of phosphor powders which are excited by UV or blue light and emit visible light, and which are used for white light-emitting d

48、iodes (LEDs).This document can be adopted for the measurement of phosphors used in non-white LEDs, for example, green, orange, pink or purple LEDs.2 Normative referencesThe following documents are referred to in the text in such a way that some or all of their content constitutes requirements of thi

49、s document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.CIE S 017/E:2011, International Lighting Vocabulary3 Terms and definitionsFor the purposes of this document, the terms and definitions given in CIE S 017/ E :2011 and the following apply.ISO and IEC maintain terminological databases for use in standardization at the following addresses: ISO Online browsing platform: available at http:/www.iso.org