Rhopoint Instruments Launches AIDO: The World’s First Inline Sensor to Measure How Coated Surfaces Really Look

Introducing AIDO. For the first time, a single inline sensor measures gloss, reflectance haze, distinctness of image (DOI) and RSPEC together, in real time, directly above the moving product.

What AIDO Measures — and Why It Matters

AIDO measures four complementary parameters that together describe how a coated surface looks to a human observer

60° Gloss provides the standard reference for overall reflectance, fully compliant with ASTM D523 and ISO 2813 and directly comparable with handheld glossmeter readings from existing quality systems.

Reflectance Haze (Log H / Log HC) captures the diffuse scatter around the specular reflection, the property responsible for the milky, shallow appearance that reduces perceived depth of finish and becomes particularly visible under bright inspection lighting or direct sunlight. Log HC applies a compensation factor for metallic and special-effect coatings, where standard haze algorithms give misleading results

DOI (Distinctness of Image) measures how sharply the environment is reflected in the surface. A surface with good DOI shows crisp, undistorted reflections; one with poor DOI makes objects in the reflection look soft and blurred, even when the gloss reading is identical. Orange peel, micro-waviness and fine surface roughness all degrade DOI without necessarily moving gloss.

RSPEC is a narrow-angle peak specular metric that is highly sensitive to fine surface texture, separating surfaces that share the same gloss level but differ in the smoothness and clarity that a viewer perceives as “depth of finish”

Reported together, these four parameters create a fingerprint of appearance quality, not just a single gloss number.

Built for the Coating Environment, Not the Laboratory

AIDO has been designed from the outset for the coating environment.

The sensor operates fully non-contact at a fixed 60 mm stand-off with a ±2 mm Z-axis tolerance. This level of positional tolerance is significant in real plants, where products move on unguided webs, vary slightly in thickness and vibrate on conveyors. AIDO does not need the surface to be perfectly held at a fixed distance, it remains stable across the normal variation of a production line.

An integrated air-purge system continuously clears the optical path of dust, overspray and coating vapours. This is not an optional accessory: in a coil coating, powder or spray paint environment, contamination of optical surfaces is one of the primary causes of inline sensor failure. AIDO is designed to run in these conditions continuously, without requiring the kind of maintenance intervention that takes sensors out of service and creates gaps in the measurement record.

Because AIDO operates without contact, it can be positioned close to the coating and cure process, measuring appearance while the coating is still hot, still fresh, still able to be influenced by process adjustments.

From Measurement to Control

AIDO runs at up to ten measurements per second;  a complete record of how appearance evolves across every metre of product. Measurement data is streamed in real time through a REST API, designed for direct integration with PLCs, manufacturing execution systems (MES), SPC platforms and factory data systems. This means that AIDO’s appearance data can sit alongside process variables such as line speed, oven temperature, film build, humidity, in the same data environment, allowing engineers to see correlations between process conditions and appearance outcomes.

A New Category of Inline Measurement

Inline gloss sensors have existed for decades. They are well understood, widely deployed and effective at what they measure. AIDO is the next step beyond them.

By combining gloss, haze, DOI and RSPEC in a single non-contact inline head, AIDO introduces a category of measurement that has not previously existed outside the laboratory: complete, perception-aligned appearance measurement at production speed. It is the first sensor to bring the full set of appearance parameters that define how a coated surface actually looks to a human observer onto the manufacturing line in real time.

For technical specifications, application information or to request a demonstration, contact Rhopoint Instruments at sales@rhopointinstruments.com.