NIR Online Thickness Measurement System - AMT/HW-CHY

Based on the principle of selective absorption of near-infrared spectroscopy,Non-contact, non-destructive, onlineMeasure the areal density of organic webs and coatings / thickness, can simultaneously measure moisture, mostly used for real-time closed-loop quality control in roll-to-roll production lines, no radioactivity.AMT/HW-CHY

Working principle

Based onLambert - Beer lawnear-infrared light (780~2500nm) irradiates the material, organicC-H bond,O-H bonds selectively absorb near-infrared light of specific wavelengths; the thicker the material and the higher the areal density, the stronger the light absorption. Through multi-wavelength comparison algorithms, interference is deducted, and the result is converted intoAreal density (gram weight)When the material density is stable, thickness can be output; multi-layer co-extrusion film can separately analyze the thickness of each layer.

Another type: near-infrared spectral interference method, used for transparent films and semiconductor thick films, analyzing film thickness through interference of reflected light from the upper and lower surfaces of the film.

System composition

1. Near-infrared optical probeNear-infrared light source, optical filter, photodetector; divided into transmission type / Reflective type
2. Scanning frame (optional)Transverse scanning, generating transverse thickness profile curves
3. Controller / Industrial control unitSpectral signal acquisition, model calculation, data storage
4. Output interface：4-20mA、RS485、Modbusdocking withPLC/DCS
5. Host computer softwareReal-time curves, thickness distribution, over-limit alarms, reports, historical traceability

 Measurement parameters

Film layer thickness, areal density (gram weight), moisture content; single layer / Multi-layer organic coatings, films.

 Applicable scenarios

• Lithium battery: electrode coating, separator thickness / Online areal density monitoring
• Plastic film:BOPP、PET、PE Multi-layer co-extrusion film
• Packaging: self-adhesive, tape, release paper back adhesive coating
• Paper making / Non-woven fabric: paper basis weight, non-woven fabric areal density
• Rubber, textiles, adhesive coatings, polymer sheets

Core advantages

•  Non-contact non-destructive measurementdoes not scratch the web, no radioactive source, safe and environmentally friendly
•  Fast response speed, can be fixed-point / Transverse scanning, real-time monitoring of web thickness uniformity
• One set of systemSimultaneously measure thickness + Moisture
•  Suitable for multi-layer co-extruded materials, can distinguish the thickness of each individual layer
• ✅ No nuclear radiation, no nuclear safety filing required, simple operation and maintenance