[article] in OVS : Optometry & Vision Science > vol. 100, 04 (Avril 2023) Titre : | Display Characterization for Contrast Sensitivity Testing | Type de document : | article de périodique | Auteurs : | Gerard C. de Wit, P | Année de publication : | 2023 | Langues : | Français (fre) | Descripteurs (mots clés) : | [Thésaurus Mesh]Sensibilité au contraste [Thésaurus Mesh]Tests de vision
| Mots-clés : | écran LCD | Résumé : | SIGNIFICANCE: Contrast sensitivity measurements using a computer display have been reported to lack accuracy when displaying small contrasts. This report investigates if the characterization/calibration of display luminance may contribute substantively to these kinds of described inaccuracies. PURPOSE: This study aimed to investigate what errors in contrast sensitivity may result from characterizing a display by fitting a gamma curve through physical or psychophysical luminance measurement data. METHODS: The luminance functions of four different in-plane switching liquid crystal displays (IPS LCDs) have been measured for all 256 gray levels (the actual luminance function). This has been compared with a gammafitted luminance curve (the gamma luminance function). Calculated are the errors in displayed contrast that may arise when assuming the gamma luminance function instead of the actual luminance function. RESULTS: The amount of error differs considerably between the displays. In general, for large contrasts (Michelson logCS <1.5), the error may become unacceptably high (>0.15 log unit). CONCLUSIONS: To improve the accuracy of testing contrast sensitivity with an LCD, it is necessary to fully characterize the display, measuring the luminance of each gray level instead of fitting a smooth gamma function through limited luminance data. | Permalink : | https://bibliotheque.helb-prigogine.be/opac_css/index.php?lvl=notice_display&id= |
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