IAI Latent Print Certification Practice Test

Vacuum Metal Deposition (VMD) is particularly suitable for non-porous surfaces, which includes polythene plastic. The process involves the physical vapor deposition of metal onto a surface under a vacuum, allowing for the creation of a thin metallic film. This technique is effective on materials that do not absorb moisture or contaminants, making polythene plastic an ideal candidate.

Polythene is often used for packaging and other applications where fingerprints may be left behind, and VMD can effectively enhance the visibility of these latent prints by providing a reflective surface that contrasts well with the fingerprint ridges. The thin metallic layer can reveal detail that might otherwise be difficult to see.

In contrast, finishes like glass, wood, and metal may not benefit in the same way from VMD due to their different porous and non-porous characteristics, as well as their surface texture. While VMD can be applied to glass and metal, the effectiveness and clarity of the resulting prints can vary. Wood, being more porous, may absorb the metal and not yield the same level of detail in the prints.