Blood stains are important traces in forensic casework. When blood exits the human body, oxyhemoglobin auto-oxidizes into methemoglobin, which in turn denatures into hemichrome. This causes a color change, which can be measured quantitatively with visible spectroscopy. We identified blood non-destructively, using a multi-component fit of the hemoglobin derivatives. The relative amount of these derivatives gives an indication of the age.
The focus of my research is to translate the developed blood stain identification and age estimation techniques from spectroscopy to hyperspectral imaging. Using hyperspectral imaging, the optical properties of an entire crime scene can be recorded rapidly and evidence within the scene can be interpreted in its original context. We introduced the use of hyperspectral imaging to automatically detect and identify blood stains at the crime scene, and simultaneosly estimate their age.