Xerography

Related terms

ESDA

Electrostatic Detection Apparatus; detects latent indentations in paper by charging the surface and cascading toner particles, revealing tracing stylus pressure and writing...

Inkjet Printing

Non-impact printing that sprays liquid ink droplets onto paper. Two main technologies: thermal (HP, Canon, bubble-jet) and piezoelectric (Epson).

IR Luminescence

Emission of near-infrared radiation by ink dye molecules when excited by visible light; different ink formulations luminesce at different intensities, allowing differentiation...

MIC / Yellow Tracking Dots

Machine Identification Code: faint yellow micro-dots printed by many colour laser printers and copiers on every page, encoding serial number and timestamp....

Oblique-Light Photography

Photography of a document surface using illumination at a low angle (10 to 15 degrees from the paper plane), which casts shadows...

Photographic Reproduction

Lab-side imaging of a questioned document using controlled lighting (oblique, transmitted, coaxial), filters and wavelengths from UV through visible to IR, to...

Transmitted-Light Photography

Light passed through the paper from behind to reveal watermarks, paper-fibre disturbance, security threads, erasures and chemical thinning.

VSC-8000

Video Spectral Comparator by Foster + Freeman, the standard QD instrument in CFSL and GEQD labs, with broadband visible, UV (254, 365...

Explained in

• Reproduction of Documents: Photographic and Mechanical MeansDry electrophotographic process invented by Chester Carlson (1938). Photoconductive drum is charged, exposed to image, dusted with toner, transferred to paper...