Multi-Layer Paint Coating
Thickness Measurement on Metallic Substrates
Terahertz Technology for Primer, Base Coat, Clear Coat or Top Coat
DFT Measurement.
Car paint shops handle high production volumes, multiple paint colors, large metallic body panels and a mix of automated and manual coating operations. TeraNIM-Auto helps measure multi-layer paint coating thickness non-destructively, enabling production teams to reduce destructive cross-section checks and build a digital DFT control workflow for metallic parts such as doors, fenders, bonnets, roofs, hoods, pillars and body panels.
Why Automotive Paint Shops Need Better Multi-Layer DFT Control?
In today’s fast-paced automotive industry, consistent paint quality is essential for appearance, corrosion protection and long-term durability. Automotive OEM paint shops operate with high production volumes, multiple paint colors, automated and manual coating processes, and tight coating specifications. However, many paint shops still rely on manual, time-consuming and destructive inspection methods, making it difficult to maintain consistent multi-layer coating quality.Even small variations in individual coating layers can affect final finish, performance, durability and paint consumption, leading to costly rework, material waste and reduced production efficiency
- High-volume paint shops need faster DFT feedback
- Plastic parts require layer-wise control because primer, base coat and clear coat each affect adhesion, colour, gloss and durability.
- Non-destructive Terahertz DFT measurement can help paint-shop teams move from sample cutting/manual checks to digital, repeatable coating control.
Compared with conventional thickness measurements, Terahertz-based inspection can detect reflections from individual coating interfaces, providing information about layer build-up and helping paint-shop teams identify coating variation more effectively. This supports a digital, data-driven DFT control workflow for modern automotive manufacturing.
Conventional Automotive Paint Thickness Measurement Challenges
How Terahertz Technology Work for Paint Coating Assessment
TeraLumen’s patented Terahertz Technology System generated THz waves from 0.1 to 5THz bandwidth. The THz waves refract and reflect at every coating layer interface. When sufficient dielectric contrast is >10% between coating layers. The time separation between interface reflections contains information about the optical thickness of each coating layer.
TeraNIM Automotive Inspection Workflow
- Component substrate - Metallic, plastic or composite substrate
- Coating Stack – Primer, Base Coat and Top Coat
- Reference measurement method
- THz Calibration setup
- Define Locations
- Set Tolerance Limits and alarms
- The measurement setup is then optimized for the specific automotive part
- Measurement Location
- THz Waveform
- Individual Layer Thickness
- Total Thickness
- Pass / Fail Result
- Operator Remarks
Results can be stored digitally for comparison, reporting and paint-process analysis.
Key Advantages to Automotive OEM’s
- Scrap Reduction – Not damaging the surface to do the inspection.
- Real-time Inspection – Enables to inspect every component.
- Reduce Rejections/Rework – Insights on coating deviations.
- Industry 4.0 – Reduction in human errors, digital transformation of manufacturing and industrial processes.
Automotive Paint Quality Control with TeraNIM™
TeraNIM™ provides a non-contact approach for evaluating individual layers within validated automotive paint systems. By combining THz reflection measurement, coating-specific calibration and digital analysis, the system can support automotive paint quality control, coating-process development, OEM specification verification and automated production inspection.
Solution With
TeraNIM
Frequently Asked Questions
Can TeraNIM-Auto measure clear coat, base coat and primer separately?
Yes, if the coating interfaces produce sufficient THz contrast and the coating stack is calibrated. For very thin layers or low-contrast stacks, total DFT or selected-layer measurement may be more reliable.
Can it work on plastic bumpers and trims?
Yes. Painted plastic and polymer components are key targets for TeraNIM-Auto, subject to sample validation and surface access.
Is it inline or offline?
TeraNIM-Auto can be configured as lab, batch-wise, line-side inspection cell or robot-assisted workflow. Full inline integration is defined after validation.
Does THz replace microscopy?
No. Optical microscopy remains useful as a reference method. THz reduces destructive routine checks once the calibration and acceptance criteria are proven.
What data does the system provide?
Waveform, measurement location, layer thickness or total DFT, tolerance result, operator notes and exportable QC report.
Automated Multi-layer Coating measurements systems with Terahertz Technology
The Challenge: Outdated Manual Inspection Methods
In today’s fast-paced automotive industry, maintaining paint quality is essential for both aesthetics and durability. However, many paint shops still rely on manual, slow, and error-prone inspection methods, which:
- Are incompatible with modern automation systems
- Cannot accurately measure multiple paint layers
- Cause 1–5% vehicle rejections due to inconsistent coating quality
This leads to costly reworks, wasted materials, and a negative impact on production efficiency and sustainability.
Our Solution: THz-Based Coating Inspection System
At Teralumen Solutions, we’re transforming coating measurement with our advanced Terahertz-Time Domain system. A powerful Terahertz Non-Destructive Testing (NDT) device designed to measure precisely.
Key Features of Our THz System:
- Multi-Layer Thickness
In a single scan, all layer’s thicknesses can be measured automatically.
- Micron-Level Precision
Accurately measures individual layers: primer, basecoat, and clear coat—even on curved surfaces.
- Real-Time Measurement
Seamlessly integrates with robotic arms and production lines for continuous, contactless inspection.
- Defect & Delamination Detection
Identifies hidden defects such as poor adhesion or air pockets that traditional methods can’t detect.
How It Works
- THz Waves Penetrate Paint Layers:
THz pulses are transmitted through all paint layers without damaging the surface. - Reflections Are Captured & Analyzed:
Each layer’s boundary generates a reflection due to change in polymer density, enabling precise thickness and defect analysis. - Instant Display of Results:
The Time-of-Flight of Terahertz waves are converted into thickness values and are shown in real time — allowing immediate feedback and action.
Unlike traditional destructive tests, THz technology enables non-contact, inline analysis — without halting production — making it ideal for modern, automated paint shops.
Key Benefits
By implementing terahertz technology, manufacturers can achieve up to 15% cost savings and reduce energy consumption per car. It helps to minimize defects and manual errors through inline robotic integration and operates with a user-friendly interface.
Fast &
Accurate
Harmless
Terahertz waves
Single and Multi-
Layer Measurement
Upto 3 THz
bandwidth for
highest precision
and repeatability
Any Base
Material
User centric
software
CONCLUSION for Automated Multi-layer Coating measurements systems
Teralumen delivers advanced terahertz inspection systems designed for automotive paint shops quality control. Our technology enables real-time, multi-layer coating thickness measurement with unmatched accuracy and safety — helping manufacturers to reduce defects, energy consumption and improve producitivity.