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Research and Testing

Near Infrared (NIR) test

The biggest change from the existing standard, NIR contrast helps cameras read plates.

ANPR plays an increasingly important role in enforcement and commercial applications.

However, 3% of plates are currently misread by ANPR cameras* - a potential 1 million vehicles being misidentified every day, and that's before cloned plates.

The E rules should reduce that number by ensuring the right NIR contrast between the plate background and plate digits - meaning the plate can be read at speed.

How are plates tested?

Six plates of every construction must be submitted alongside a description of the materials used to make them.

A pair of white and yellow standard oblong plates, plus a yellow motorcycle plate is printed to show specified markings.

A large black square is used for retroreflectivity testing of black characters and the characters B and 8 help evaluate the NIR contrast.

What makes a fail?

If the contrast between the black digits and coloured backgrounds is not sufficient, the plate has failed.

* Surveillance Camera Commissioner speech at the national ANPR conference 2017.