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Updated: Jul 7, 2026
06:48
A Multimodal Wide-Field Fourier-Transform Raman Microscope
Published on: December 30, 2025
[Spectral analysis of ball pen script by FTIR microscope with ATR objective]
1Shimadzu International Trading (Shanghai) Co., Ltd, Shanghai Analytical Applications Center, Shanghai 200020, China. sshhth@shimadzu.com.cn
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|February 12, 2008
Summary
Infrared microscopy with an attenuated total reflectance (ATR) objective enables non-destructive analysis of ball pen ink. This method overcomes low reflectivity issues, allowing detailed inspection of forensic evidence.
Area of Science:
- Forensic Science
- Analytical Chemistry
- Spectroscopy
Context:
- Ball pen script analysis is crucial in public security and justice.
- Traditional infrared microscopy methods struggle with low-reflectivity paper and dark ink.
- Accurate spectral analysis of ball pen ink is challenging due to sample properties.
Purpose:
- To develop a non-destructive method for inspecting ball pen script using infrared microscopy.
- To overcome limitations of reflectance mode for low-reflectivity samples.
- To obtain pure ball pen ink spectra by subtracting paper fiber interference.
Summary:
- An infrared microscope with an attenuated total reflectance (ATR) objective was employed for analyzing ball pen ink.
- Mixed spectra of ink and paper were obtained and processed to isolate the ink spectrum.
- Key spectral peaks identified crystal violet pigment and oil reagent alkyd, enabling ink characterization.
- Mapping software generated a 3D graph of spectral distribution, visualizing the ball pen trace.
Impact:
- This technique allows for non-destructive, detailed inspection of original ball pen scripts.
- Provides a reliable method for forensic analysis of ink evidence.
- Enhances the capabilities of public security and justice investigations through advanced analytical techniques.
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