Here is why we have three of these units.....
Function
The SIRCH IE® KRIMESITE™ IMAGER is an image intensified device which locates untreated fingerprints and
other evidence of forensic interest on non-porous surfaces by the Reflected UV technique. No treatment with powders
or chemicals is necessary. Use of the Imager greatly enhances results obtained by cyanoacrylate fuming.
The KRIMESITE™ IMAGER is most effective on non-porous surfaces, but can detect fresh prints on some porous
surfaces.
Background
We see, or are able to image an object either because it emits light or because it reflects light incident upon it.
Objects that reflect light do so in a characteristic manner: They may reflect strongly or weakly, specularly or diffusely,
and they may reflect some colors and not others. For example, the sunlight impinging on a healthy leaf is made up
of all visible colors. The leaf will absorb most of those colors, but will strongly reflect a particular range of colors back
to our eyes, which is, of course, why it appears green to us. Other objects reflect other colors. It is differences in the
reflective properties of materials that allow us to distinguish objects that do not emit their own light. Such differences
in reflectance extend to most materials and to most wavelengths of radiation. Our eyes easily detect subtle differences
in reflectance in the visible light wavelengths. But there are wavelengths that our eyes do not see. Instruments
designed to see in those wavelengths show us the world in a new perspective.
Detection and enhancement of fingerprints by reflection of short wavelength UV light has long been reported in
Forensic Journals. In brief, differences in reflectance exist between a fingerprint and the surface on which it is located;
although they may be slight, instruments can be designed to amplify and enhance those differences.
The SIRCH IE® KRIMESITE™ IMAGER is one of a new generation of such instruments. It utilizes a micro-channel
plate-based image intensifier in conjunction with optics specifically designed to image short wavelength (ultraviolet)
light and a series of special bandpass filters to allow you to see untreated fingerprints even in daylight.
Team JBI
