Do 3D or 4D Number Plates Affect ANPR Cameras?
Plate Legality · 10 January 2025 · 4 min read
A common concern — will 3D or 4D number plates cause problems with ANPR cameras or speed cameras? Here's the definitive answer.
Do 3D or 4D Number Plates Affect ANPR Cameras?
This is one of the most common questions we receive. The short answer: no, properly manufactured 3D gel and 4D plates do not cause problems with ANPR cameras.
Let's look at the science behind why.
How Do ANPR Cameras Work?
ANPR (Automatic Number Plate Recognition) cameras use infrared (IR) light to read number plates. The camera emits IR light towards the vehicle, and the plate's retroreflective background bounces that light back to the sensor. The characters, being non-reflective (solid black), create high contrast that the camera's optical character recognition (OCR) software reads.
ANPR systems are used by:
- UK Police forces — for tracking stolen vehicles, wanted persons, and uninsured drivers
- National Highways — for average speed cameras and traffic monitoring
- DVLA — for automated enforcement of vehicle tax and insurance
- Private parking companies — for car park entry/exit monitoring
- Dart Charge and congestion zones — for automated toll collection
Why 3D and 4D Plates Work Perfectly with ANPR
The key factor for ANPR readability is the contrast between the reflective background and the black characters. Whether those characters are flat-printed, raised gel, or raised acrylic, this contrast remains identical.
Both 3D gel and 4D acrylic characters are:
- Solid black — providing clear, high contrast against the reflective background
- Applied on top of the reflective material — not blocking or reducing its reflectivity
- Correctly sized and spaced using the Charles Wright 2001 font
As long as the plate meets BS AU 145e standards, ANPR cameras can read it without any difficulty.
When Could There Be ANPR Problems?
ANPR issues can arise with illegal modifications, such as:
- Tinted or coloured characters — reducing the contrast ratio that cameras rely on
- Non-standard fonts or spacing — confusing OCR software
- Anti-flash coatings or covers — deliberately designed to reduce plate readability (illegal under Section 43 of the Vehicle Excise and Registration Act 1994)
- Damaged or dirty plates — where characters are obscured by dirt, damage, or wear
These modifications are illegal regardless of plate type and can result in a fine of up to £1,000, points on your licence, or even a court summons.
What About Speed Cameras?
Speed cameras — including average speed cameras) (SPECS/VECTOR), Gatso, and Truvelo systems — all use the same ANPR/IR technology. Legal 3D and 4D plates are read perfectly by every type of speed camera operating in the UK.
What About Car Parks and Toll Systems?
Modern car park ANPR systems (used by companies like APCOA and NCP) and toll systems like Dart Charge use the same infrared technology. Legal plates work without issues.
Our ANPR Guarantee
Every plate manufactured by Limitless Plates is BS AU 145e compliant and designed to be read clearly by all ANPR systems. We use only DVLA-approved retroreflective material and solid black characters.
If you're choosing between plate styles, check out our comparison: Standard vs 3D vs 4D Number Plates. Ready to order? Build your plates now with our 3D configurator.