IEC TR 62471-4:2022

Photobiological safety of lamps and lamp systems - Part 4: Measuring methods

IEC 62471-4:2022, which is a Technical Report, provides manufacturers, test houses, safety personnel and others with practical guidance on methods to perform radiometric and spectroradiometric measurements to determine the level of accessible optical radiation emitted by lamps and lamp systems in accordance with IEC 62471.

General Information

• Status: Published
• Publication Date: 21-Sep-2022
• ICS: 29.140.01 - Lamps in general
• ICS: 31.260 - Optoelectronics. Laser equipment
• Technical Committee: TC 76 - Optical radiation safety and laser equipment
• Drafting Committee: WG 9 - TC 76/WG 9
• Current Stage: PPUB - Publication issued
• Start Date: 01-Nov-2022
• Completion Date: 22-Sep-2022

Standards Content (Sample)

IEC TR 62471-4 ®
Edition 1.0 2022-09
TECHNICAL
REPORT
colour
inside
Photobiological safety of lamps and lamp systems –
Part 4: Measuring methods
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IEC TR 62471-4 ®
Edition 1.0 2022-09
TECHNICAL
REPORT
colour
inside
Photobiological safety of lamps and lamp systems –

Part 4: Measuring methods
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.140.01, 31.260 ISBN 978-2-8322-5734-0

– 2 – IEC TR 62471-4:2022 © IEC 2022
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms . 10
4 Application . 10
4.1 General . 10
4.2 Safety precautions . 10
4.3 Hazard assessment overview . 10
4.4 Selection of hazards . 11
4.5 Assessment levels . 11
4.6 Initial filtering . 12
4.7 Measurement quantities . 12
4.7.1 Emission wavelengths . 12
4.7.2 Irradiance . 13
4.7.3 Radiance . 14
4.7.4 Source size and location . 16
4.7.5 Temporal emission . 18
4.8 Measurement uncertainty . 18
5 Test conditions . 19
5.1 General . 19
5.2 Dark room (level A) . 19
5.3 Environmental conditions (level A) . 19
5.4 Power supply . 19
5.5 Product configuration . 19
5.5.1 General . 19
5.5.2 Warm up . 20
5.5.3 Measurement distance . 20
5.6 Optical alignment . 22
6 Performance characteristics: level A instruments . 22
6.1 General . 22
6.2 Spectral irradiance and radiance . 23
6.2.1 Spectral analysis . 23
6.2.2 Entrance optics . 25
6.2.3 Calibration standards . 26
6.3 Imaging devices . 27
6.4 Temporal emission . 27
6.5 Source size and location . 28
7 Performance characteristics: level B instruments . 28
7.1 General . 28
7.2 Irradiance or radiance . 28
7.2.1 General . 28
7.2.2 UV lines . 29

7.2.3 Narrow band sources . 29
7.2.4 Known spectral distribution . 29
7.2.5 Luminance-based . 30
7.3 Apparent source location and subtense . 31
7.4 Temporal emission . 31
Annex A (informative) Hazard selection . 32
Annex B (informative) Instrumentation description . 33
B.1 Double monochromators . 33
B.2 Single monochromators . 33
B.3 Array spectrometers . 33
B.4 Detectors . 33
B.5 Entrance optics . 34
B.6 Measurement geometries . 36
B.6.1 Irradiance . 36
B.6.2 Radiance . 36
B.7 2D imaging detector . 39
Annex C (informative) Extrapolation of spectral irradiance for thermal radiators . 41
Annex D (informative) Temporal emission measurement . 43
D.1 General . 43
D.2 Pulse duration . 43
D.3 Averaged irradiance and averaged radiance . 44
Annex E (informative) Uncertainty analysis . 47
Annex F (informative) Application examples . 48
F.1 General . 48
F.2 Example 1 – LED flashlight . 48
F.3 Example 2 – Infrared tungsten filament lamp . 49
F.4 Example 3 – Compact fluorescent lamp (CFL) . 51
F.5 Example 4 – LED bulb . 53
Annex G (informative) Stray radiation . 54
Annex H (informative) Report . 56
H.1 General . 56
H.2 Report. 56
Annex I (informative) Relationship between "true" source radiance and spatially
averaged radiance . 58
Bibliography . 62

Figure 1 – Schematic representation of irradiance measurement . 14
Figure 2 – Consideration of filling of FOV . 15
Figure 3 – Example of a direct measurement of radiance using a lens and aperture. 15
Figure 4 – Indirect measurement of radiance . 16
Figure 5 – Example of a rectangular source . 18
Figure 6 – Example of the non-uniform radiance distribution . 18
Figure 7 – Example of the emission profiles . 22
Figure B.1 – Examples of the diffuser optics . 35
Figure B.2 – Schematic representation of irradiance measurement . 36
Figure B.3 – Geometry of radiance measurement with a single thin lens . 37

– 4 – IEC TR 62471-4:2022 © IEC 2022
Figure B.4 – Geometry of a general radiance measurement . 38
Figure B.5 – Setup of the aperture stop behind the lens . 38
Figure B.6 – Setup of the aperture stop in front of the lens . 39
Figure B.7 – Example of a 2D imaging detector . 40
Figure D.1 – Example of temporal pulse wave .
...