Microspectrophotometry (MSP)
Definition
Visible-range spectrophotometry conducted through a microscope, generating an absorbance curve that fingerprints the dye on a single fibre without destroying it.
- Spectral range
- Visible, often extended to UV-NIR
- Instrument
- Spectrophotometer coupled to a microscope
- Output
- Absorbance curve unique to the dye
- Sample impact
- Non-destructive, single fibre usable again
Common questions
Why is MSP valuable for fibre comparison specifically?+
Fibre evidence is often a single strand recovered from a scene, so a technique that generates a discriminating chemical signature without consuming or damaging that fibre lets it be re-examined or retested later, including by an opposing expert.
How does MSP add discrimination beyond visual colour matching?+
Two fibres that look the same colour to the eye can still produce measurably different absorbance curves because of subtle differences in dye formulation or concentration, giving MSP finer discriminating power than visual or even standard microscopic colour comparison.
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