Laser-induced breakdown spectroscopy (LIBS) was tested for all of the relevant issues in forensic examinations of commercial inks, including classification of pen inks on one paper type and on different paper types, determination of the deposition order of layered inks, and analysis of signatures and toners on one questioned document. The scope of this work was to determine the potential of a single LIBS setup that is compatible with portable instruments for different types of ink analysis, rather than building a very large database for inks and papers. We identified up to seven metals characteristic for the examined inks, which allowed to fully discriminate all eight black inks on one type of printing paper. When the inks were tested on ten different papers, the correct classification rates for some of them were reduced for reasons thoroughly studied and explained. The replicated tests on three crossing points, each one involving a pair of blue or black inks, were successful in five cases out of six. In the test simulating documents of forensic interest (questioned documents), LIBS was able to correctly identify the differences in three inks used for signatures on one of the three pages and the use of different printing inks on each page of the document.

中文翻译：

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通过激光诱导击穿光谱法（LIBS）对商业油墨进行法医分析。

在商用墨水的法医检查中，对激光诱导击穿光谱法（LIBS）的所有相关问题进行了测试，包括对一种纸张类型和不同纸张类型的笔墨水进行分类，确定层状墨水的沉积顺序以及分析一份有问题的文件上的签名和碳粉。这项工作的范围是确定与便携式仪器兼容以进行不同类型墨水分析的单个LIBS设置的潜力，而不是为墨水和纸张建立一个非常大的数据库。我们为所检查的墨水确定了多达七种金属特征，从而可以完全区分一种打印纸上的所有八种黑色墨水。当在十种不同的纸上测试墨水时，由于彻底研究和解释的原因，降低了其中一些的正确分类率。在三个交叉点上进行了重复测试，每个交叉点都涉及一对蓝色或黑色墨水，在六分之五的情况下均成功。在模拟模拟取证的文件（有问题的文件）中，LIBS能够正确地识别出三页纸中用于签名的三种墨水和文件每一页中使用的不同印刷墨纸之间的差异。