Ghost Image
Definition
A faint background impression of a previously copied document visible in a later photocopy, arising from incomplete cleaning of residual toner from the drum surface after the previous copy cycle.
- Cause
- Incomplete drum cleaning between copy cycles
- Appearance
- Faint background impression of a prior document
- Source device
- Photocopier
- Related evidence
- Toner analysis
Common questions
How can a ghost image help establish a document's copying history?+
A ghost image can reveal that a machine previously copied a different document, and matching the ghost pattern to a known prior document can link a specific copy to a specific earlier copying event on that machine.
Is a ghost image the same as a drum defect or trash mark?+
No, a ghost image comes from residual toner of a previous document, while a drum defect or trash mark is a physical imperfection on the drum itself that appears consistently across all copies from that machine.
Does every photocopier produce ghost images?+
No, well maintained machines with effective drum cleaning rarely produce visible ghosting, so its presence often points to a specific machine's maintenance condition or heavy prior use.
Related terms
- Copy Generation
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- Fax Header Bar
- The line of text printed at the top of each received fax page under regulatory requirements (US FCC 47 CFR 68.318, UK...
- FTIR (Fourier Transform Infrared Spectroscopy)
- A vibrational spectroscopy technique used in toner analysis to identify the polymer backbone and functional group composition of toner binder material; ATR...
- MMR Compression (Modified Modified READ)
- An ITU-T fax compression standard (T.6) used in high-quality fax transmission modes; produces characteristic compression artefacts visible in fine character strokes of...
- Platen Glass
- The flat transparent surface on which original documents are placed for scanning in a photocopier or flatbed scanner; contamination or scratches on...
- Polyester Toner
- A toner binder formulation based on polyester resin, dominant in office photocopiers and laser printers from the 2000s onward; characterised by FTIR...
- SEM-EDX
- Scanning electron microscopy with energy-dispersive X-ray spectroscopy. The electron beam excites characteristic X-rays from each element present in the target grain, giving...
- Trash Mark
- An extraneous mark appearing at a consistent position or periodic interval in photocopied documents, arising from platen glass contamination (fixed position) or...