GB/T 43979-2024Evaluation methods for visual comfort of indoor LED displays (English PDF)

1 Scope

GB/T 43979-2024 gives the Chinese methods for evaluating the visual comfort of indoor LED displays. Fine-pitch LED has moved out of stadiums and into meeting rooms, control rooms, classrooms and retail interiors, where people sit close to it for hours, and the qualities that made it good for a stadium, very high brightness and saturated colour, are exactly what make it uncomfortable indoors. The standard sets the evaluation indicators and the methods for each: the luminance and its adaptation to the ambient level, the luminance uniformity and the visibility of the pixel structure at the viewing distance, the flicker measured by the appropriate metrics including short-term and stroboscopic effect, the blue light content, the contrast and glare relative to the surroundings, the colour rendering and colour uniformity, and the viewing angle behaviour, together with the measurement conditions and instruments, the calculation of the comfort indicators and their grading, and the report. It took effect on 25 April 2024.

This document describes the light comfort evaluation method for indoor LED display (hereinafter referred to as "LED displays"). This document is applicable to the evaluation of light comfort of LED displays.

2 Normative references

The contents of the following documents constitute the essential terms of this document through normative references in the text. Among them, for dated references, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies to this document.

GB/T 43770-2024 Specification for indoor LED displays

GB/T 43978-2024 Evaluation requirements for visual comfort of indoor LED displays SJ/T 11141-2017 Generic specification for LED displays SJ/T 11281-2017 Measure methods of light emitting diode (LED) displays

3 Terms and definitions

The terms and definitions, which are defined in GB/T 43770-2024, GB/T 43978-2024, SJ/T 11141-2017, SJ/T 11281-2017, apply to this document.

4 General requirements

4.1 Test conditions Unless otherwise specified, the test conditions are as follows:

a) Ambient temperature. 15 °C ~ 35 °C;

b) Relative humidity. 20% ~ 80%;

c) Atmospheric pressure. 86 kPa ~ 106 kPa;

d) AC power supply. (220 ± 22) V, (50 ± 1) Hz;

e) Test environment. There shall be no mechanical vibration, electromagnetic and photoelectric interference that may affect the test accuracy;

f) Test distance. All tests are conducted outside the minimum line of sight.

4.2 Test instruments and software Unless otherwise specified, the performance of all test instruments shall meet the following requirements and be calibrated by a third-party organization. During the calibration period, the test shall be conducted in accordance with the relevant operating procedures.

a) Color luminance meter (similar instruments used to test optical properties such as brightness and chromaticity can also be used). The relative indication error of brightness is within ±5%; the absolute indication error of chromaticity coordinates is within ±0.003 (relative to standard A light source).

b) Imaging brightness meter. Relative brightness indication error within ±5%.

c) Illuminance meter. Relative illumination indication error within ±4%.

d) Thermometer. Absolute temperature indication error within ±0.5 °C.

e) Laser rangefinder. Absolute distance indication error within ±1 mm.

f) Photoelectric sensor. Frequency response not less than 50 MHz.

5 Evaluation method...