SIST EN ISO 11554:2008
(Main)Optics and photonics - Lasers and laser-related equipment - Test methods for laser beam power, energy and temporal characteristics (ISO 11554:2006)
Optics and photonics - Lasers and laser-related equipment - Test methods for laser beam power, energy and temporal characteristics (ISO 11554:2006)
This International Standard specifies test methods for determining the power and energy of continuous-wave and pulsed laser beams, as well as their temporal characteristics of pulse shape, pulse duration and pulse repetition rate. Test and evaluation methods are also given for the power stability of cw-lasers , energy stability of pulsed lasers and pulse duration stability. The test methods given in this International Standard are used for the testing and characterization of lasers.
Optik und Photonik - Laser und Laseranlagen - Prüfverfahren für Leistung, Energie und Kenngrößen des Zeitverhaltens von Laserstrahlen (ISO 11554:2006)
Dieses internationale Dokument legt Prüfverfahren zur Bestimmung der Leistung und Energie von
Dauerstrich- und Pulslasern sowie für die Kenngrößen für das Zeitverhalten fest: Pulsform, Pulsdauer und
Pulsfolgefrequenz. Prüf- und Auswerteverfahren für die Leistungsstabilität von Dauerstrichlasern,
Energiestabilität von Pulslasern und Pulsdauerstabilität werden ebenfalls angegeben.
Die Prüfverfahren, die in dieser Internationalen Norm angegeben werden, dienen zur Prüfung und
Charakterisierung von Lasern.
Optique et photonique - Lasers et équipements associés aux lasers - Méthodes d'essai de la puissance et de l'énergie des faisceaux lasers et de leurs caractéristiques temporelles (ISO 11554:2006)
L'ISO 11554:2006 spécifie des méthodes d'essai pour la détermination de la puissance et de l'énergie des faisceaux lasers continus et impulsionnels ainsi que leurs caractéristiques temporelles de forme et de durée d'impulsion et de fréquence de répétition des impulsions. Elle indique, en outre, des méthodes d'essai et d'évaluation de la stabilité de la puissance des lasers continus, de la stabilité de l'énergie des lasers impulsionnels et de la stabilité de la durée d'impulsion.
Les méthodes d'essai données dans l'ISO 11554:2006 sont destinées à être utilisées pour les essais et la détermination des caractéristiques des lasers.
Optika in fotonska tehnologija - Laserji in laserska oprema - Preskusne metode za moč žarka, energijo in časovne karakteristike (ISO 11554:2006)
General Information
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Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Optik und Photonik - Laser und Laseranlagen - Prüfverfahren für Leistung, Energie und Kenngrößen des Zeitverhaltens von Laserstrahlen (ISO 11554:2006)Optique et photonique - Lasers et équipements associés aux lasers - Méthodes d'essai de la puissance et de l'énergie des faisceaux lasers et de leurs caractéristiques temporelles (ISO 11554:2006)Optics and photonics - Lasers and laser-related equipment - Test methods for laser beam power, energy and temporal characteristics (ISO 11554:2006)31.260Optoelektronika, laserska opremaOptoelectronics. Laser equipmentICS:Ta slovenski standard je istoveten z:EN ISO 11554:2008SIST EN ISO 11554:2008en01-november-2008SIST EN ISO 11554:2008SLOVENSKI
STANDARDSIST EN ISO 11554:20061DGRPHãþD
SIST EN ISO 11554:2008
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN ISO 11554July 2008ICS 31.260Supersedes EN ISO 11554:2006
English VersionOptics and photonics - Lasers and laser-related equipment -Test methods for laser beam power, energy and temporalcharacteristics (ISO 11554:2006)Optique et photonique - Lasers et équipements associésaux lasers - Méthodes d'essai de la puissance et del'énergie des faisceaux lasers et de leurs caractéristiquestemporelles (ISO 11554:2006)Optik und Photonik - Laser und Laseranlagen -Prüfverfahren für Leistung, Energie und Kenngrößen desZeitverhaltens von Laserstrahlen (ISO 11554:2006)This European Standard was approved by CEN on 22 June 2008.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2008 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 11554:2008: ESIST EN ISO 11554:2008
EN ISO 11554:2008 (E) 2 Contents Page Foreword.3 Annex ZA ((informative)
Relationship between this European Standard and the Essential Requirements of EU Directive 98/37/EC.4 Annex ZB (informative)
Relationship between this
European
Standard and the Essential Requirements of EU Directive 2006/42/EC.5
SIST EN ISO 11554:2008
EN ISO 11554:2008 (E) 3 Foreword The text of ISO 11554:2006 has been prepared by Technical Committee ISO/TC 172 “Optics and optical instruments” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 11554:2008 by Technical Committee CEN/TC 123 “Lasers and photonics” the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by January 2009, and conflicting national standards shall be withdrawn at the latest by January 2009. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 11554:2006. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EC Directive(s). For relationship with EC Directives, see informative Annexes ZA and ZB, which are integral part of this document. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 11554:2006 has been approved by CEN as a EN ISO 11554:2008 without any modification.
SIST EN ISO 11554:2008
EN ISO 11554:2008 (E) 4 Annex ZA ((informative)
Relationship between this European Standard and the Essential Requirements of EU Directive 98/37/EC
This European Standard has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association to provide one means of conforming to Essential Requirements of the New Approach Directive for machinery 98/37/EC amended by Directive 98/79/EC. Once this standard is cited in the Official Journal of the European Communities under that Directive and has been implemented as a national standard in at least one Member State, compliance with the normative clauses of this standard confers, within the limits of the scope of this standard, a presumption of conformity with the corresponding Essential Requirements 1.5.10 Radiation and 1.5.12 Laser equipment of that Directive and associated EFTA regulations. WARNING: Other requirements and other EU Directives may be applicable to the products falling within the scope of this International standard.
SIST EN ISO 11554:2008
EN ISO 11554:2008 (E) 5 Annex ZB (informative)
Relationship between this
European
Standard and the Essential Requirements of EU Directive 2006/42/EC This European Standard has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association to provide a means of conforming to Essential Requirements of the New Approach Directive 2006/42/EC on machinery. Once this standard is cited in the Official Journal of the European Communities under that Directive and has been implemented as a national standard in at least one Member State, compliance with the normative clauses of this standard confers, within the limits of the scope of this standard, a presumption of conformity with the relevant Essential Requirements 1.5.10 Radiation and 1.5.12 Laser radiation of that Directive and associated EFTA regulations. WARNING — Other requirements and other EU Directives may be applicable to the product(s) falling within the scope of this standard.
SIST EN ISO 11554:2008
SIST EN ISO 11554:2008
Reference numberISO 11554:2006(E)© ISO 2006
INTERNATIONAL STANDARD ISO11554Third edition2006-05-01Optics and photonics — Lasers and laser-related equipment — Test methods for laser beam power, energy and temporal characteristics Optique et photonique — Lasers et équipements associés aux lasers —Méthodes d'essai de la puissance et de l'énergie des faisceaux lasers et de leurs caractéristiques temporelles
SIST EN ISO 11554:2008
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SIST EN ISO 11554:2008
ISO 11554:2006(E) © ISO 2006 – All rights reserved iiiContents Page Foreword.iv Introduction.v 1 Scope.1 2 Normative references.1 3 Terms and definitions.1 4 Symbols and units of measurement.2 5 Measurement principles.3 6 Measurement configuration, test equipment and auxiliary devices.3 6.1 Preparation.3 6.2 Control of environmental impacts.6 6.3 Detectors.6 6.4 Beam-forming optics.7 6.5 Optical attenuators.7 7 Measurements.7 7.1 General.7 7.2 Power of cw lasers.7 7.3 Power stability of cw lasers.8 7.4 Pulse energy of pulsed lasers.8 7.5 Energy stability of pulsed lasers.8 7.6 Temporal pulse shape, pulse duration, rise time, fall time and peak power.8 7.7 Pulse duration stability.8 7.8 Pulse repetition rate.8 7.9 Small signal cut-off frequency.9 8 Evaluation.9 8.1 General.9 8.2 Power of cw lasers.9 8.3 Power stability of cw lasers.10 8.4 Pulse energy of pulsed lasers.10 8.5 Energy stability of pulsed lasers.10 8.6 Temporal pulse shape, pulse duration, rise time, fall time and peak power.10 8.7 Pulse duration stability.13 8.8 Pulse repetition rate.13 8.9 Small signal cut-off frequency.13 9 Test Report.13 Annex A (informative)
Relative intensity noise (RIN).16 Bibliography.18
SIST EN ISO 11554:2008
ISO 11554:2006(E) iv © ISO 2006 – All rights reserved Foreword ISO (the 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 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 electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. 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. ISO 11554 was prepared by Technical Committee ISO/TC 172, Optics and photonics, Subcommittee SC 9, Electro-optical systems. This third edition cancels and replaces the second edition (ISO 11554:2003), which has been technically revised. For the purposes of this International Standard, the CEN annex regarding fulfilment of European Council Directives has been removed.
SIST EN ISO 11554:2008
ISO 11554:2006(E) © ISO 2006 – All rights reserved vIntroduction The measurement of laser power (energy for pulsed lasers) is a common type of measurement performed by laser manufacturers and users. Power (energy) measurements are needed for laser safety classification, stability specifications, maximum laser output specifications, damage avoidance, specific application requirements, etc. This document provides guidance on performing laser power (energy) measurements as applied to stability characterization. The stability criteria are described for various temporal regions (e.g., short-term, medium-term and long-term) and provide methods to quantify these specifications. This International Standard also covers pulse measurements where detector response speed can be critically important when analysing pulse shape or peak power of short pulses. To standardize reporting of power (energy) measurement results, a report template is also included. This International Standard is a Type B standard as stated in ISO 12100-1. The provisions of this International standard may be supplemented or modified by a Type C standard. Note that for machines which are covered by the scope of a Type C standard and which have been designed and built according to the provisions of that standard, the provisions of that Type C standard take precedence over the provisions of this Type B standard. SIST EN ISO 11554:2008
SIST EN ISO 11554:2008
INTERNATIONAL STANDARD ISO 11554:2006(E) © ISO 2006 – All rights reserved 1Optics and photonics — Lasers and laser-related equipment — Test methods for laser beam power, energy and temporal characteristics 1 Scope This International Standard specifies test methods for determining the power and energy of continuous-wave and pulsed laser beams, as well as their temporal characteristics of pulse shape, pulse duration and pulse repetition rate. Test and evaluation methods are also given for the power stability of cw-lasers, energy stability of pulsed lasers and pulse duration stability. The test methods given in this International Standard are used for the testing and characterization of lasers. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the last edition of the referenced document (including any amendments) applies. ISO 11145:2006, Optics and optical instruments — Lasers and laser-related equipment — Vocabulary and symbols IEC 61040:1990, Power and energy measuring detectors, instruments and equipment for laser radiation International vocabulary of basic and general terms in metrology (VIM). BIPM, IEC, IFCC, ISO, IUPAC, IUPAP, OIML, 2nd ed. 1993 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 11145, in the VIM and the following apply. 3.1 relative intensity noise RIN R(f) single-sided spectral density of the power fluctuations normalized to the square of the average power as a function of the frequency f NOTE 1 The relative intensity noise R(f) or RIN as defined above is explicitly spoken of as the “relative intensity noise spectral density”, but usually simply referred to as RIN. NOTE 2 For further details, see Annex A. 3.2 small signal cut-off frequency fc frequency at which the laser power output modulation drops to half the value obtained at low frequencies when applying small, constant input power modulation and increasing the frequency SIST EN ISO 11554:2008
ISO 11554:2006(E) 2 © ISO 2006 – All rights reserved 4 Symbols and units of measurement The symbols and units specified in ISO 11145 and in Table 1 are used in this International Standard. Table 1 — Symbols and units of measurement Symbol Unit Term f Hz Frequency fc Hz Small signal cut-off frequency [f1, f2] Hz Frequency range for which the relative intensity noise R(f) is given k 1 Coverage factor for the determination of uncertainty m 1 Reading m 1 Mean value of readings P W Power averaged over the sampling period P W Mean power, averaged over the measurement period at the operating conditions specified by the manufacturer ∆P 1 Relative power fluctuation to a 95 % confidence level for the appropriate sampling period [∆P (1 µs) and/or ∆P (1 ms) and/or ∆P (0,1 s) and/or ∆P (1 s)] Q J Mean pulse energy ∆Q 1 Relative pulse energy fluctuation to a 95 % confidence level R(f) Hz−1 or dB/Hz Relative intensity noise, RIN S(t) 1 Detector signal s 1 Measured standard deviation T s Pulse repetition period t s Measurement period Urel 1 Expanded relative uncertainty corresponding to a 95 % confidence level (coverage factor k = 2) Urel(C) 1 Expanded relative uncertainty of calibration corresponding to a 95 % confidence level (coverage factor k = 2) τF s Fall time of laser pulse ∆τH 1 Relative pulse duration fluctuation with regard to τH to a 95 % confidence level τR s Rise time of laser pulse ∆τ10 1 Relative pulse duration fluctuation with regard to τ10 to a 95 % confidence level
NOTE 1 For further details regarding 95 % confidence level see ISO 2602 [1]. NOTE 2 The expanded uncertainty is obtained by multiplying the standard uncertainty by a coverage factor k = 2. It is determined according to the Guide to the Expression of Uncertainty in Measurement [3]. In general, with this coverage factor, the value of the measurand lies with a probability of approximately 95 % within the interval defined by the expanded uncertainty. NOTE 3 R(f) expressed in dB/Hz equals 10 lg R(f) with R(f) given in Hz−1. SIST EN ISO 11554:2008
ISO 11554:2006(E) © ISO 2006 – All rights reserved 35 Measurement principles The laser beam is directed on to the detector surface to produce a signal with amplitude proportional to the power or energy of the laser. The amplitude versus time is measured. Radiation emitted by sources with large divergence angles is collected by an integrating sphere. Beam forming and attenuation devices may be used when appropriate. The evaluation method depends on the parameter to be determined and is described in Clause 8. 6 Measurement configuration, test equipment and auxiliary devices 6.1 Preparation 6.1.1 Sources with small divergence angles The laser beam and the optical axis of the measuring system shall be coaxial. Select the diameter (cross-section) of the optical system such that it accommodates the entire cross-section of the laser beam and so that clipping or diffraction loss is smaller than 10 % of the intended measurement uncertainty. Arrange an optical axis so that it is coaxial with the laser beam to be measured. Suitable optical alignment devices are available for this purpose (e.g., aligning lasers or steering mirrors). Mount the attenuators or beam-forming optics such that the optical axis runs through the geometrical centres. Care should be exercised to avoid systematic errors. NOTE 1 Reflections, external ambient light, thermal radiation and air currents are all potential sources of errors. After the initial preparation is completed, make an evaluation to determine if the entire laser beam reaches the detector surface. For this determination, apertures of different diameters can be introduced into the beam path in front of each optical component. Reduce the aperture size until the output signal has been reduced by 5 %. This aperture should have a diameter at least 20 % smaller than the aperture of the optical component. For divergent beams, the aperture should be placed immediately in front of the detector to assure total beam capture. NOTE 2 Remove these apertures before performing the power (energy) measurements described in Clause 7. 6.1.2 Sources with large divergence angles The radiation emitted by sources with large divergence angles shall be collected by an integrating sphere. The collected radiation is subjected to multiple reflections from the wall of the integrating sphere; this leads to a uniform irradiance of the surface proportional to the collected flux. A detector located in the wall of the sphere measures this irradiance. An opaque screen shields the detector from the direct radiation of the device being measured. The emitting device is positioned at or near the entrance of the integrating sphere, so that no direct radiation will reach the detector. Figure 1 shows an integrating sphere measurement configuration for a small emitting source positioned inside the integrating sphere. Large-sized sources should, of course, be positioned outside the sphere but close enough to the input aperture so that all emitted radiation enters the sphere. SIST EN ISO 11554:2008
ISO 11554:2006(E) 4 © ISO 2006 – All rights reserved
Key 1 integrating sphere 3 device being measured 2 diffusing opaque screen 4 detector Figure 1 — Schematic arrangement for the measurement of highly divergent sources 6.1.3 RIN measurement The measuring arrangement for determination of the RIN is shown in Figure 2. The beam propagates through the lens, an attenuator or other lossy medium, and falls on the detector. When adjusting the measuring arrangement, feedback of the output power into the laser shall be minimized to avoid measurement errors. The RIN, R(f) is determined at reference plane A, before any losses. The Poisson component of the RIN is increased at plane B due to losses, and again at plane C due to inefficiency in the detection process. NOTE For an explanation of the different components of RIN, see Annex A. To measure RIN, an electrical splitter sends the dc detector signal produced by a test laser to a meter while the ac electrical noise is amplified and then displayed on an electrical spectrum analyser. RIN depends on numerous quantities, the primary ones being: ⎯ frequency; ⎯ output power; ⎯ temperature; ⎯ modulation frequency; ⎯ time delay and magnitude of optical feedback; ⎯ mode-suppression ratio; ⎯ relaxation oscillation frequency. Consequently, variations or changes in these quantities should be minimized during the measurement process. SIST EN ISO 11554:2008
ISO 11554:2006(E) © ISO 2006 – All rights reserved 56.1.4 Measurement of small signal cut-off frequency For determination of the small signal cut-off frequency, fc, of lasers, the laser is modulated as described in 7.9 and the ac output power measured. Figure 3 shows the basic measurement arrangement for the case of diode lasers. When adjusting the measuring arrangement, feedback of the output power into the laser shall be minimized to avoid measurement errors.
Key 1 laser 5 electrical splitter 2 lens 6 meter 3 attenuator or other lossy medium 7 pre-amplifier 4 detector 8 electrical spectrum analyser A reference plane that defines RIN B Poisson RIN increases due to losses C detector adds shot-noise RIN NOTE See reference [4]. Figure 2 — Measurement arrangement for RIN determination
Key D device being measured G1 adjustable frequency ac generator PD detector (e.g. photodetector) G2 dc generator M measuring instrument for ac output power C1, C2 coupling capacitors Figure 3 — Measurement arrangement for determination of the small signal cut-off frequency of diode lasers SIST EN ISO 11554:2008
ISO 11554:2006(E) 6 © ISO 2006 – All rights reserved 6.2 Control of environmental impacts Take suitable precautions, such as vibration mechanical and acoustical isolation of the test set-up, shielding from extraneous radiation, temperature stabilization of the laboratory and choice of low-noise amplifiers, in order to ensure that the contribution to the total error is less than 10 % of the intended uncertainty. Check by performing background measurements such as described in Clause 7, but with the laser beam blocked from the detector (e.g. by a beam stop in the laser resonator or close to the laser output). The value for the standard deviation (laser beam blocked) obtained by an evaluation as described in Clause 8 shall be smaller than one tenth of the value obtained from a measurement with the laser beam reaching the detector. 6.3 Detectors The radiation detector shall be in accordance with IEC 61040:1990, in particular with Clauses 3 and 4. Furthermore, the following points shall be noted: a) Calibrated power (energy) meter: ⎯ any wavelength dependency, non-linearity or non-uniformity of the detector or the electronic device shall be minimized or corrected by use of a calibration procedure; ⎯ the direct measurement, i.e. using a planar-surface detector without an integrating sphere, can only be used when it has been determined that the sensitivity of the detector is uniform and independent on incident angles, α, to within at least the divergence angle, Θ, of the incident beam (see Figure 4) and the entire beam reaches the sensitive surface of the detector; for measuring beams with large divergence, an integrating sphere detector should be used to assure collection of all the emitted radiation [see 6.3, b)]; ⎯ detectors used for all quantitative measurements shall be calibrated with traceability back to relevant national standards.
Key 1 planar detector Θ divergence angle of the beam α maximum acceptance angle Figure 4 — Planar detector — Illustration of angles b) Calibrated integrating sphere: ⎯ the area of the sphere openings shall be small compared to the overall surface area of the sphere; ⎯ the inner surface of the sphere and screen shall have a uniform diffusing coating with a high reflectance (ρ > 0,9); ⎯ the total losses through the sphere ports shall be less than 5 %; SIST EN ISO 11554:2008
ISO 11554:2006(E) © ISO 2006 – All rights reserved 7⎯ if the device being measured is mounted inside the sphere, the sphere surface shall be large com
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