<title>Construction of a programmable light source for use as a display calibration artifact</title>

Abstract

A light source with a programmable spectral output was designed and constructed following the identification of limitations in current display calibration techniques. Current calibration of a display measurement instrument compares the measured spectral output of a pre-calibrated reference light source with the calibration data traceable to national standards. This allows correction factors to be calculated for each wavelength and entered into the measurement instrument. However, the reference light source used to create these correction factors is very dissimilar in spectral output to test displays such as cathode ray tubes (CRT) or liquid crystal displays (LCDs). The dissimilarity between the reference calibration spectrum and the spectrum of the test display gives errors at some wavelengths, which leads to inaccurate measurement of colour and luminance, and inter-instrument disagreement. The development of a light source with a programmable spectrum, will allow display measurement instruments to be calibrated against a reference source that mimics the spectrum of the device under test, improving the accuracy of measurements and the agreement between display measurement instruments. This paper describes the prototype programmable source and demonstrates the feasibility of mimicking both CRT and LCD spectra. The programmable source could be used as a transfer standard to assess display measurement techniques in international laboratories.

Research on Color Correction of Multi-Spectral Camera Based on Spectral Tunable Integrating Sphere

“…统和空间滤波器组成的光谱分布可调谐的光源系统， 该系统结构复杂、 产生的光谱形状有限且辐射能量低， 难以用于工程实践 [7] 。随着发光二级管(LED)技术的发展， 特别是大功率蓝光和白光 LED 的出现， LED 光源 得到广泛应用， 研究者开始提出研制基于 LED 的光谱可调光源， 例如美国标准与技术研究所(NIST)设计的 基 于 LED 的 光 谱 可 调 积 分 球 光 源 (STIS) [8] 。 在 国 内 安 徽 光 学 精 密 机 械 研 究 所 、 长 春 光 学 精 密 机 械 研 究 所 以 及台湾国立中央大学等研究机构也做了类似的研究 [9][10] 2式可以定量地计算地物的颜色三刺激值 [12] 。传统的白平衡 目 标 光 谱 不 匹 配 造 成 的 定 标 误 差 ； 在 大 口 径 光 谱 可 调 积 分 球 光 源 控 制 系 统 设 置 地 物 光 谱 数 据 库 ， 收 集 各 种 地 物 光 谱 ， 通 过 模 拟 各 种 种 类 的 地 物 光 谱 对 多 光 谱 相 机 进 行 色 度 定 标 ， 定 标 系 数 对 于 后 续 处 理 多 光 谱 图 像 具 有 重 要 作 用 ， 可 以 有 效 地 解 决 多 光 谱 成 像 设 备 颜 色 失 真 现 象 ； 此 外 光 谱 可 调 积 分 球 光 源 可 用 于 探 测 器 以 及遥感设备的光谱辐射定标。 参 考 文 献…”

Spectrally Tunable Sources for Advanced Radiometric Applications

“…A variety of different approaches to the development of spectrally tunable sources have recently been described, including the use of spatial light modulators [ 2 , 4 , 7 , 8 ] or light-emitting diodes (LEDs) [ 3 , 5 , 6 , 9 , 10 ]. In this work, we describe an ARS based around a dispersing element and a spatial light modulator (SLM).…”

“…Thus, a fully integrated radiometric characterization and calibration facility would have the capability of generating standardized sets of spatially complex scenes with high spectral fidelity [ 1 ]. Spectrally programmable light sources are under development for use in medical endoscopes [ 2 ]; for use as standard source distributions [ 3 , 4 ]; and for general use in radiometric, colorimetric, and photometric research [ 5 , 6 ], while spectral scene generators have been proposed for infrared calibrators [ 7 ].…”

LED-based spectrally tunable source for radiometric, photometric, and colorimetric applications

“…10 This source suffers from low flux, especially in the UV, due to the SPD of the lamp. 10 This source suffers from low flux, especially in the UV, due to the SPD of the lamp.…”