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Background Statement for SEMI Draft Document 5634D NEW STANDARD: TEST METHOD for COLOR REPRODUCTION and PERCEPTUAL CONTRAST of DISPLAYS

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Background Statement for SEMI Draft Document 5634D NEW STANDARD: TEST METHOD for COLOR REPRODUCTION and PERCEPTUAL CONTRAST of DISPLAYS Background Statement for SEMI Draft Document 5634D NEW STANDARD: TEST METHOD FOR COLOR REPRODUCTION AND PERCEPTUAL CONTRAST OF DISPLAYS NOTICE: This Background Statement is not part of the balloted item. It is provided solely to assist the recipient in reaching an informed decision based on the rationale of the activity that preceded the creation of this ballot. NOTICE: For each Reject Vote, the Voter shall provide text or other supportive material indicating the reason(s) for disapproval (i.e., Negative[s]), referenced to the applicable section(s) and/or paragraph(s), to accompany the vote. NOTICE: Recipients of this ballot are invited to submit, with their Comments, notification of any relevant patented technology or copyrighted items of which they are aware and to provide supporting documentation. In this context, ‘patented technology’ is defined as technology for which a patent has been issued or has been applied for. In the latter case, only publicly available information on the contents of the patent application is to be provided. Background As high quality properties of digital TV like HDTV, 4K UHDTV and 8K UHDTV have been demanded, it is necessary to present the highest image quality with rich and authentic color, subtle gray and color tone and dynamic contrast, and set the suitable and advanced evaluation methods of display quality. The aim of various methods for measuring color gamut, brightness, and contrast based on human perception have been studied is to match the image quality with human eyes. Even though there are conventional measuring methods like luminance, tristimulus values for the objective evaluation method, there are imperfect methods considering a viewing condition, perceptual parameters. The basic rationale of this document is the color appearance model which is proposed at CIE in 2002. A new method is to calculate a color volume and contrast with color appearance model which is uniform color space with human visual perception. The ballot results will be reviewed and adjudicated at the meetings indicated in the table below. Check www.semi.org/Standards under Standards Calendar for the latest update. Review and Adjudication Information Task Force Review Committee Adjudication To be reviewed at the Korea Perceptual Korea FPD Metrology Technical Group: Image Quality TF Meeting Committee Date: May 12, 2017 May 12, 2017 Time & Time Zone: 10:00pm – 12:00pm (KST) 13:00pm – 14:00pm (KST) Location: SEMI Korea office SEMI Korea office City, State/Country: Seoul, Korea Seoul, Korea Jong Ho Chong (Samsung Display) JongSeo Lee (Samsung Display) [email protected] [email protected] Leader(s): Il-Ho Kim (LMS) [email protected] Natalie Shim (SEMI Korea) Natalie Shim (SEMI Korea) Standards Staff: 82.2.531.7808 82.2.531.7808 [email protected] [email protected] This meeting’s details are subject to change, and additional review sessions may be scheduled if necessary. Contact the task force leaders or Standards staff for confirmation. Telephone and web information will be distributed to interested parties as the meeting date approaches. If you will not be able to attend these meetings in person, but would like to participate by telephone/web, please contact Standards staff. SEMI DRAFT 673 S. Milpitas Blvd. Milpitas, CA 95035-5446 Document Number: 5634D Phone: 408.943.6900 Date: 2017-03-20 SEMI Draft Document 5634D New Standard: TEST METHOD FOR COLOR REPRODUCTION AND PERCEPTUAL CONTRAST OF DISPLAY 1 Purpose 1.1 This Standard specifies measurement conditions and methods for describing the visual color quality in 3- BALLOT dimensional color space, and the perceived contrast with perceptual parameters in color electronic display devices. 1.2 The CIE1 XYZ color space is derived from the experimental results and it has been used to set color performance of displays in CIE xy or u’v’ chromaticity diagram without brightness. 1.3 For measurement, setting test patterns based on Average Picture Level (APL) of IEC2 62087:2011 are required, instead of full screen patterns, which are composed with small size of window box. The full screen patterns are not suitable for emissive displays which of luminance are adjusted with contents. LETTER 1.4 The contrast ratio has been widely used although the calculated value is dramatically changed by dark state luminance. This metric does not consider human visual characteristics. Therefore, it is more reliable to consider the perceptual indices. 2 Scope 2.1 This Standard is applicable to the color electronic display devices, except on the transparent display. 2.2 This Standard includes the measurement for physical data, analysis, and calculation methods which have perceptual factors. 2.3 The term “perceptual” is subject to CIECAM02 (CIE Color Appearance Model 2002) in this Standard. NOTICE: SEMI Standards and Safety Guidelines do not purport to address all safety issues associated with their use. It is the responsibility of the users of the Documents to establish appropriate safety and health practices, and determine the applicability of regulatory or other limitations prior to use. 3 Limitation 3.1 Measurements are subject to errors or imprecision due to the user, environmental factors, and mis-calibration of measurement system or measurement system limitations. 3.2 Results may vary with ambient illumination conditions or in the presence of uncontrolled stray light reflections. 4 Referenced Standards and Documents 4.1 IDMS 4.1.1 Information Display Measurement Standard (IDMS) 1.0 4.2 CIE Standards 4.2.1 CIE 15.3 — Colorimetry 4.2.2 CIE 159 — CIECAM02 4.3 IEC Standards 4.3.1 IEC 62341-6-2 — OLED Displays — Measuring methods of visual quality and ambient performance 4.3.2 IEC 62087 — Methods of measurement for the power consumption of audio, video and related equipment. NOTICE: Unless otherwise indicated, all documents cited shall be the latest published versions. 1 Commission Internationale De L'eclairage (International Commission On Illumination), Kegelgasse 27, A-1030 Vienna/AUSTRIA. Telephone: +43.1.714.31.87.0. Fax : +43.1.714.31.87.18 ; http://www.cie.co.at 2 International Electrotechnical Commission, 3 rue de Varembé, Case Postale 131, CH-1211 Geneva 20, Switzerland. Telephone: 41.22.919.02.11; Fax: 41.22.919.03.00; http://www.iec.ch This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline. Permission is granted to reproduce and/or distribute this document, in whole or in part, only within the scope of SEMI International Standards committee (document development) activity. All other reproduction and/or distribution without the prior written consent of SEMI is prohibited. Page 1 Doc. 5634D SEMI SEMI DRAFT 673 S. Milpitas Blvd. Milpitas, CA 95035-5446 Document Number: 5634D Phone: 408.943.6900 Date: 2017-03-20 5 Terminology 5.1 Abbreviations and Acronyms 5.1.1 APL — average picture level. 5.1.2 FOV — field of view 5.1.3 PCL — perceptual contrast length BALLOT 5.1.4 VCRC — volume color reproduction capability 5.1.5 LMD — light measurement device 5.1.6 DUT — device under test 5.2 Definitions 5.2.1 brightness — the attribute of a human visual sensation according to which an area appears to emit more or less LETTER light 5.2.2 color gamut boundary — the outer surface determined by a color gamut form 5.2.3 perceptual contrast length — the difference of black and white brightness of the screen 5.2.4 volume color reproduction capability — the volume of the perceived color gamut obtained in 3–dimensional color space which is composed of colorfulness, hue and brightness 6 Standard Measurement Condition 6.1 Measuring Conditions 6.1.1 Environmental conditions 6.1.1.1 In order to obtain accurate measured data, the following environmental conditions are required. Temperature: 25±2 °C Humidity: 25–85 % relative humidity Pressure: 86–106 kPa Air flow: no wind Vibration / Shock: no influence 6.1.2 Ambient conditions 6.1.2.1 Dark room condition 6.1.2.1.1 The luminance contribution from the background illumination shall be less than 0.01 cd/m2. 6.1.2.2 Ambient illuminations Uniform hemispherical diffuse light source 6.1.3 Measuring equipment conditions 6.1.3.1 In this Standard, a LMD such as spectral radiometer, at least from 380 nm to 780 nm wavelength ranges or a filter photometer shall be used. 6.1.3.2 The luminance accuracy of the instrument shall be within ±2 %. And the chromaticity accuracy of the instrument shall be below: This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline. Permission is granted to reproduce and/or distribute this document, in whole or in part, only within the scope of SEMI International Standards committee (document development) activity. All other reproduction and/or distribution without the prior written consent of SEMI is prohibited. Page 2 Doc. 5634D SEMI SEMI DRAFT 673 S. Milpitas Blvd. Milpitas, CA 95035-5446 Document Number: 5634D Phone: 408.943.6900 Date: 2017-03-20 Table 1 Chromaticity Accuracy of the Instrument x,y ±0.002 (0.001 to 0.05 cd/m2) x ±0.0015 (0.05 cd/m2 or more) y 2 BALLOT ±0.001 (0.05 cd/m or more) 6.1.3.3 The measuring distance could be set 400 mm or 500 mm. For the small size display, the distance can be calculated and set that an LMD should include over 500 pixels of display at 2 degree FOV. The calculated distance should be noted in a report. 6.1.4 Viewing Direction LETTER 6.1.4.1 In the case of the uniform hemispherical diffuse illumination conditions, an integrating sphere, sampling sphere, or hemisphere shall be used.
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