Accredited Video Measuring Machine (VMM) Calibration Services

In modern micro-manufacturing, where components are too small or fragile for physical contact, the Video Measuring Machine (VMM) is indispensable. At DRS Technologies, we provide expert VMM calibration services to ensure your optical metrology systems deliver sub-micron accuracy. Our technicians verify the entire measurement chain—from the precision glass scales of the stage to the edge-detection software and zoom lens optics.

Why Optical and Coordinate Accuracy is Essential

Unlike a physical probe, a VMM relies on digital imaging to define boundaries. Over time, factors such as thermal expansion of the granite base, lens distortion (parallax), and LED lighting degradation can lead to measurement errors. Regular calibration by DRS Technologies ensures that your VMM remains compliant with ISO 10360-7, providing the high-confidence data required for medical devices, electronics, and aerospace components.

Our Technical VMM Calibration and Verification Process

The specialists at DRS Technologies follow a rigorous multi-point protocol using NIST-traceable artifacts to verify your system:

  1. Stage Linearity and Squareness: We use precision glass scales or laser interferometers to verify the X, Y, and Z-axis movements, ensuring the stage moves linearly and that the axes are perfectly orthogonal.

  2. Magnification and Distortion Audit: Using “Circle-Grid” glass masters, we verify that the zoom lens maintains consistent magnification across the entire field of view and is free from radial distortion.

  3. Edge Detection and Sub-Pixel Accuracy: We calibrate the software’s ability to recognize transitions between light and dark. This ensures that the “virtual” measurements taken by the software match the physical dimensions of the artifact.

  4. Parfocality and Coaxiality: We verify that the image remains in focus when zooming in and out (parfocality) and that the center of the image does not shift (coaxiality), which is critical for multi-step measurement routines.

  5. Certification and NIST Traceability: Every service includes a comprehensive certificate featuring “As-Found” and “As-Left” data, volumetric uncertainty budgets, and documented NIST traceability for all reference masters.

Comprehensive Support for Leading VMM Brands

DRS Technologies provides elite-level support for a wide array of optical metrology systems, including:

  • Manual and CNC VMMs: Verification of both hand-operated and automated systems.

  • Multi-Sensor Systems: Calibrating units that combine video with touch probes or laser sensors.

  • High-Magnification Systems: Specialized calibration for micro-feature measurements.

  • Brands Supported: Expert service for Mitutoyo (Quick Scope/Quick Vision), Nikon (iNexiv), Micro-Vu, and OGP (SmartScope).

Frequently Asked Questions

What is the ISO 10360-7 standard for VMMs?

ISO 10360-7 is the international standard specifically designed for the verification of “imaging measuring systems.” It defines the procedures for testing the length measurement error and the probing error, ensuring that your VMM meets global benchmarks for coordinate metrology.

How often should a VMM be calibrated?

The standard calibration interval is twelve months. However, because VMMs are sensitive to environmental changes, they should be recalibrated if the machine is moved, if there is a significant change in room temperature, or if the lighting system is replaced.

Why is lighting important in VMM calibration?

VMMs use various lighting techniques (diascopic, episcopic, and ring light) to highlight edges. If the lighting is inconsistent or uncalibrated, the edge-detection software may “see” an edge in the wrong place. We verify the illumination uniformity to ensure measurement repeatability.