🌈 Confocal Chromatic Sensors for Precision Industrial Metrology: Innovative Solutions from Micro-Epsilon! 🚀

[Mucitler Elektrik]

✨ Revolutionizing Non-Contact Measurement in Confined Spaces!​

Micro-Epsilon has expanded its confocalDT IFS2404 series with the IFS2404-18 sensor, aiming to optimize non-contact displacement measurements in confined spaces. This new optical sensor design was specifically developed for high-precision measurements.

🔍 Innovative Approach to Engineering Challenges​

Automated quality control of deep micro-well plates, fluidic dispensing channels, and narrow internal housings presents significant challenges in optical measurement. Standard optical systems can experience beam clipping when directed into deep wells or narrow gaps. Additionally, the tilt of parts on fast-moving conveyors, surface curvature, and positioning tolerances can lead to signal loss. The IFS2404-18 was specifically designed to overcome these challenges.

💡 Optical Operating Principle and Beam Path Geometry​

Confocal chromatic measurement relies on controlled chromatic aberration. A broadband white light source passes through a multi-lens optical arrangement that separates the beam into different monochromatic focal points along the optical measurement axis. When the target intersects this spectral focal line, the wavelength precisely focused on the surface reflects back through a confocal pinhole to a spectrometer. This allows the controller to determine the target distance based on the spectral wavelength rather than reflected light intensity.

🎯 IFS2404-18: Special Design for Deep Cavities​

The IFS2404-18 integrates an optical architecture with a numerical aperture of 0.17. This low numerical aperture produces a narrow, collimated light cone that penetrates deep cavities and narrow apertures without clipping adjacent walls. The sensor offers a measuring range of 18 mm, starting from an offset distance of approximately 61 mm. This configuration fills the physical gap between existing 10 mm and 28 mm range optics, providing sufficient measurement depth for component and process variations while protecting the front optical element.

📐 Angular Tolerance and Surface Versatility​

The IFS2404-18 tolerates tilt deviations with a maximum measurement angle of ±9°. This angular acceptance allows the sensor to capture stable measurement values on slightly inclined surfaces, shallow geometric sides, and misaligned workpieces. The confocal chromatic mechanism performs stable measurements on various material compositions, including bright reflective metals, diffuse ceramic surfaces, liquids, and transparent glass layers.

🌐 Expanded Sensor Series and Controller Integration​

Micro-Epsilon has expanded the IFS2404 family by releasing the IFS2404-1, IFS2404-3, and IFS2404-6 models as individual components. Additionally, the manufacturer introduced the IFS2404-4, which offers a 4 mm measuring range in a slim cylindrical housing to fit into dense automation fixtures and multi-channel inspection arrays.

📊 Non-Contact Industrial Surface Measurement Methodologies​

• Laser Triangulation: Offers high stand-off distances but experiences shadowing in steep-walled cavities.
  
• Spectral White Light Interferometry: Provides sub-nanometer axial resolution but is sensitive to target collisions due to narrow stand-off margins.
  
• Confocal Chromatic Sensing: Offers sub-micron resolution and a coaxial optical axis that eliminates optical triangulation shadows. By connecting passive sensor heads to remote spectrometers via fiber optic cables, the measuring heads remain compact, immune to electromagnetic interference, and thermally stable.
  

The IFS2404-18's numerical aperture of 0.17 and offset distance of 61 mm provide a suitable geometry for liquid level verification in multi-well plates and micro-machined holes. Pairing with IFC series controllers enables acquisition rates of up to 30 kHz, allowing dynamic in-line measurement on continuous web lines and high-speed indexing tables.