The device is a versatile luminance meter featuring a built-in spectral sensor. It is capable of measuring luminance, flicker, correlated color temperature (CCT), and color rendering index (CRI) for displays, backlight modules, lighting fixtures, and other similar applications. In addition, it can present the spectral distribution curve, allowing users to identify the characteristics and types of backlight sources with ease. Luminance Wavelength Range: 400nm ~ 700nm; Luminance Wavelength Interval: 10nm; Luminance Measurement Distance: ≤1m; Luminance Measurement Range: 1 ~1,000,000cd/m²; Luminance Resolution: 0.01cd/m²; Luminance Measurement Accuracy: ≤±(5%H+2cd/m²) (H is the standard value, calibrated with the CIE standard illuminant A ); Luminance Unit Options: cd/m² (default), fL; CCT Measurement Range: 1,000 ~ 100,000K CCT Measurement Accuracy: ±5% (Calibrated with the CIE standard illuminant A) CRI Measurement Range: 0 ~ 100 CRI Measurement Accuracy: ±2 (Calibrated with the CIE standard illuminant A) Flicker Frequency Measurement Range: 10 ~ 500 Hz Flicker Frequency Measurement Distance: ≤0.1m Flicker Frequency Measurement Accuracy: ±5% Test Aperture Diameter: Φ10mm/20mm Host Size: 147.2mm x 72mm x 28mm Probe Size: Diameter 40mm x Thickness 76mm Display: 240 x 160 Dot Matrix LCD Operating Environment: Temperature 0 ~ 40℃, Humidity Less than 85%RH Measures displays, LED panels, lamps, and various light sources. Swappable 10mm / 20mm probes for both large and small screens. Luminance range up to 1,000,000cd/m². Detects screen and lamp flicker to support eye safety. Identifies full-spectrum LEDs versus ordinary light sources. Human-eye-matched spectral sensor for accurate color capture. Measures correlated color temperature (CCT) and color rendering index (CRI). Provides real-time, maximum, minimum, and average brightness statistics. High-sensitivity digital probe ensures precise and reliable readings. Power supply: 2 x AA batteries (Not included