Polilight
Definition
Rofin / Omnichrome xenon-arc-based ALS platform developed in Australia; the reference platform for biological-fluid and fingerprint ALS validation studies in Australasian and RCMP laboratories.
- Manufacturer
- Rofin / Omnichrome
- Origin
- Australia
- Light source
- Xenon arc lamp
- Reference role
- Australasian and RCMP ALS validation studies
Common questions
What forensic tasks was the Polilight originally validated for?+
It was used as the benchmark alternate light source in early validation studies for detecting biological fluid stains, such as semen and saliva, and for visualizing latent fingerprints, establishing performance data that later ALS devices were often compared against.
Is a xenon arc ALS like the Polilight still typical of modern light sources?+
Many current ALS units have shifted to LED-based sources, which are more compact and durable, but xenon arc platforms like the Polilight remain influential as the historical reference point against which newer devices' fluorescence performance is benchmarked.
Related terms
- Alternate Light Source (ALS)
- A device emitting light at selected wavelengths (typically 415 to 535 nm) used to detect biological fluids that fluoresce or absorb light...
- Bandpass Filter
- An optical filter transmitting a defined wavelength range (typically 20-40 nm FWHM) while blocking all others; the excitation filter in an ALS...
- Crime-Lite
- A compact, battery-powered alternate light source system (Foster+Freeman) designed for scene use by scenes-of-crime officers; the Crime-lite 82S and ML2 are standard...
- DFO (1,8-Diazafluoren-9-One)
- A fluorescent ninhydrin analogue used for latent fingerprint development on porous surfaces; excite at 450-470 nm (with secondary absorption extending into the...
- Fluorescent Whitening Agent (FWA)
- An optical brightener added to synthetic fibres and paper during manufacture; fluoresces under UV-A excitation, making treated fibres and paper highly visible...
- Long-Pass (Viewing) Filter
- An optical filter transmitting all wavelengths above a defined cut-on wavelength; worn as goggles by the examiner to block excitation light while...
- Mercury Vapour Lamp
- A gas-discharge lamp producing discrete atomic emission lines, most useful at 253.7 nm (UV-C germicidal) and 365 nm (UV-A); the classic biological-fluid...
- Rhodamine 6G
- A fluorescent dye applied as a post-treatment to cyanoacrylate-developed fingerprints; excited at 530 nm (green), it emits at 565-590 nm (yellow-orange), greatly...
- Stokes Shift
- The wavelength difference between the excitation peak and the emission peak of a fluorophore. A positive Stokes shift (emission at longer wavelength...
- Tungsten-Halogen Lamp
- A broadband (thermal) light source with continuous emission from UV-A through NIR, determined by filament temperature; the first generation of forensic ALS...
- Xenon Arc Lamp
- A high-pressure xenon discharge lamp producing near-continuous white-light emission across 200-2500 nm; used in broadband ALS platforms (Polilight, CrimeScope) with bandpass filters.