IEC 62906-5-2:2016
(Main)Laser display devices - Part 5-2: Optical measuring methods of speckle contrast
Laser display devices - Part 5-2: Optical measuring methods of speckle contrast
IEC 62906-5-2:2016(E) specifies the standard measurement conditions and measurement methods for determining the monochromatic speckle contrast of laser display devices (LDDs). The LDDs may include hybrid types using both a laser or lasers, and spontaneous emission-based light sources, such as LEDs.
NOTE: The monochromatic speckle contrast measurements do not include image quality issues.
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Standards Content (Sample)
IEC 62906-5-2 ®
Edition 1.0 2016-06
INTERNATIONAL
STANDARD
colour
inside
Laser display devices –
Part 5-2: Optical measuring methods of speckle contrast
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IEC 62906-5-2 ®
Edition 1.0 2016-06
INTERNATIONAL
STANDARD
colour
inside
Laser display devices –
Part 5-2: Optical measuring methods of speckle contrast
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.260 ISBN 978-2-8322-3455-6
– 2 – IEC 62906-5-2:2016 © IEC 2016
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references. 6
3 Terms, definitions and abbreviations . 6
3.1 Terms and definitions . 6
3.2 Abbreviations . 6
4 Standard measuring conditions . 7
4.1 General . 7
4.2 Standard measuring environmental conditions . 7
4.3 Measurement coordinate system . 7
4.4 Darkroom conditions . 8
4.5 Standard conditions of measuring equipment . 8
4.5.1 General . 8
4.5.2 Adjustment of LDD . 9
4.5.3 Conditions of measuring equipment . 9
4.6 Screen conditions . 10
4.6.1 General . 10
4.6.2 Report . 10
5 Measuring methods of speckle contrast . 10
5.1 Speckle contrast measurement of still image . 10
5.1.1 Purpose . 10
5.1.2 Measuring conditions . 10
5.1.3 Measuring the monochromatic speckle contrast of front projection . 10
5.1.4 Measuring the monochromatic speckle contrast of rear projection . 12
5.2 Calibration and diagnosis of the LMD . 12
5.2.1 General . 12
5.2.2 Calibration procedure and diagnosis for the highest C . 13
s
5.2.3 Calibration procedure and diagnosis for the lowest C . 13
s
Annex A (informative) Spectral behaviour of the LD . 15
A.1 Spectral behaviour of a single-longitudinal mode LD . 15
A.2 Spectral behaviour of a multi-longitudinal mode LD . 15
Annex B (informative) Recommendation on imaging sensor pixel size . 16
Annex C (informative) Fundamental formulation of speckle contrast and the effects of
measurement variables . 18
C.1 Fundamental formulation . 18
C.2 Effect of observation distance and iris radius . 18
Annex D (informative) Possible errors and their sources . 20
Bibliography . 21
Figure 1 – Coordinate system for projection direction and viewing direction. 8
Figure 2 – Example of measurement geometries for monochromatic speckle contrast
of front projection . 11
Figure 3 – Example of measurement geometries for monochromatic speckle contrast
of rear projection . 12
Figure 4 – Example of measurement geometries for C calibration . 13
s
Figure A.1 – Example of spectral behaviour of a single-longitudinal mode LD . 15
Figure A.2 – Example of spectral behaviour of a multi-longitudinal mode LD . 15
Figure B.1 – Minimum subjective speckle grain size as a function of the F-number . 17
Figure C.1 – Measurement result of C by changing NA . 19
s screen-Iris
Table B.1 – Example of s . 16
subj
– 4 – IEC 62906-5-2:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LASER DISPLAY DEVICES –
Part 5-2: Optical measuring methods of speckle contrast
FOREWORD
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International Standard IEC 62906-5-2 has been prepared by IEC technical committee 110:
Electronic display devices.
The text of this standard is based on the following documents:
FDIS Report on voting
110/760/FDIS 110/768/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62906 series, published under the general title Laser display
devices, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
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– 6 – IEC 62906-5-2:2016 © IEC 2016
LASER DISPLAY DEVICES –
Part 5-2: Optical measuring methods of speckle contrast
1 Scope
This part of IEC 62906 specifies the standard measurement conditions and measurement
methods for determining the monochromatic speckle contrast of laser display devices (LDDs).
The LDDs may include hybrid types using both a laser or lasers, and spontaneous emission-
based light sources, such as LEDs.
NOTE The monochromatic speckle contrast measurements do not include image quality issues.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
unda
...
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