Back-illuminated charged-coupled device (BI-CCD) arrays increase quantum efficiency but also amplify etaloning, a multiplicative, wavelength-dependent fixed-pattern effect. When spectral data from hundreds of BI-CCD rows are combined, the averaged spectrum will generally appear etalon-free. This can mask substantial etaloning at the row level, even if the BI-CCD has been treated to suppress the effect. This paper compares two methods of etalon correction, one with simple averaging and one with row-by-row calibration using a fluorescence standard. Two BI-CCD arrays, both roughened by the supplier to reduce etaloning, were used to acquire Raman spectra of murine bone specimens. For one array, etaloning was the dominant source of noise under the exposure conditions chosen, even for the averaged spectrum across all rows; near-infrared-excited Raman peaks were noticeably affected. In this case, row-by-row calibration improved the spectral quality of the average spectrum. The other CCD’s performance was shot-noise limited and therefore received no benefit from the extra calibration. The different results highlight the importance of checking for and correcting row-level fixed pattern when measuring weak Raman signals in the presence of a large fluorescence background.

背照式电荷耦合器件 (BI-CCD) 阵列提高了量子效率，但也放大了标准具，这是一种乘法的、波长相关的固定模式效应。当组合来自数百个 BI-CCD 行的光谱数据时，平均光谱通常看起来没有标准具。这可以掩盖行级别的大量标准具，即使 BI-CCD 已被处理以抑制效果。本文比较了两种标准具校正方法，一种是简单平均，另一种是使用荧光标准进行逐行校准。两个 BI-CCD 阵列均由供应商粗糙化以减少标准具，用于获取鼠骨标本的拉曼光谱。对于一个阵列，标准具是所选曝光条件下的主要噪声源，即使对于所有行的平均光谱也是如此；近红外激发的拉曼峰明显受到影响。在这种情况下，逐行校准提高了平均光谱的光谱质量。另一个 CCD 的性能受到散粒噪声的限制，因此无法从额外的校准中受益。不同的结果突出了在存在大荧光背景的情况下测量弱拉曼信号时检查和校正行级固定模式的重要性。