Tungsten-Halogen Lamp
Definition
A broadband (thermal) light source with continuous emission from UV-A through NIR, determined by filament temperature; the first generation of forensic ALS platforms.
- Source type
- Broadband thermal light source
- Spectral range
- Continuous emission from UV-A through NIR
- Emission driver
- Filament temperature
- Historical role
- First generation of forensic ALS platforms
Common questions
Why has the tungsten-halogen lamp largely been superseded in modern forensic light sources?+
Its broadband thermal emission cannot be tuned to a narrow wavelength band the way LED or laser-based alternate light sources can, and it generates more heat, so newer platforms offer sharper wavelength selection with less thermal output for the same fluorescence work.
Does the continuous spectrum give the tungsten-halogen lamp any advantage over narrowband sources?+
Its broad continuous output covers a wide range of excitation wavelengths from a single lamp, which is useful for general-purpose examination without swapping filters, even though it lacks the intensity a narrowband source delivers at any one wavelength.
Related terms
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