Instrumentation: Document Examination Equipment
The field of forensic document examination has progressed significantly in the last several years. Historically, examinations were essentially limited to a signature or handwriting comparisons, typewritten documents, rubber stamp impressions, embossments, etc. Technology has evolved to enhance document examinations with instruments that differentiate inks, identify security features, recover indented writing, enhance images, etc.
Two examples of specialized document examination equipment are shown below.
Video Spectral Comparator 4Plus
(Foster & Freeman)
The multifaceted testing capabilities of the VSC 4Plus include differentiating inks (common to alterations), verification of security documents, visualization of UV activated fluorescent features and fibers, watermarks and surface features of paper (embossments, intaglio printing, etc.)
Indented Writing Materializer
Although not commonly considered, indented writing on documents may provide important evidence in questioned signature, handwriting and other cases. The document is placed on top of the instrument, covered with a polymer film and an electrostatic charge applied. A black powder is brushed onto the surface, attracted to the indentations present. Once the process is completed, an adhesive film is applied to the polymer film, preserving the evidence obtained without causing harm or marks on the questioned document.
Other laboratory instruments are available and utilized appropriate to individual case needs.