In modern precision inspection systems, all data collected by sensors and probes rely on a stable and credible geometric origin. Many equipment developers focus on optimizing probe accuracy and increasing sensor sampling frequency, yet they tend to overlook errors originating from the reference carrier. Even top-grade probes will produce systematic deviations in all measured data once the reference surface undergoes tiny deformation. The high-flatness granite inspection base undertakes this underlying supporting role and continuously builds a stable and reliable reference carrier for various sensors and probes. Based on the R&D and manufacturing of ultra-precision components, UNPARALLELED Group keeps developing granite reference bases adapted to working conditions of sensors and probes for optical, semiconductor and metrology inspection equipment.
The measurement logic of sensors and probes is essentially comparative measurement. Dimension, contour and position data captured by probes all take the base plate surface as the reference origin. Metal platforms are prone to expansion and contraction under temperature changes, while internal stress of ordinary stone is continuously released, leading to slow fluctuation of the plate surface and zero drift of probes. Such drift will not appear immediately but accumulate with temperature variation and vibration, worsening the repeat positioning accuracy of sensors and causing inconsistent measurement results for the same workpiece in multiple tests. With dense crystal structure and excellent thermal stability, UNPARALLELED® black granite restrains plate warping caused by temperature fluctuation to the maximum extent and maintains the long-term stable geometric shape of the reference surface, ensuring every collection of sensors and probes is built on a consistent and unchanged reference.
Different types of probes and sensors have differentiated requirements for the micro-state of reference surfaces. Contact probes require flat, wear-resistant and scratch-resistant plate surfaces; laser sensors and optical imaging sensors demand uniform and stable micro-morphology of the reference surface to avoid optical imaging interference from local reflection and surface defects. Processing lines and pore defects on ordinary processed plates will disturb optical sensor imaging and even cause abnormal wear of probes for contact measuring heads. UNPARALLELED Group adopts the gradient ultra-precision grinding process to conduct fine shaping and pore sealing treatment on granite plate surfaces. While achieving high flatness indicators, it optimizes the micro texture of plate surfaces, satisfies application demands of both contact probes and non-contact optical sensors, and avoids measurement noise induced by micro defects on reference surfaces.
Under dynamic inspection working conditions, vibration interference will be directly transmitted to probes and sensors and amplify measurement errors. In scenarios such as AOI visual inspection, XY linear motor platforms and laser contour scanning, probes work at high speed. Once the base shakes slightly due to vibration, clutter will appear in sensor signals. High flatness is not merely a static indicator; the overall rigidity and vibration isolation capacity of the base are equally vital. In the structural design phase of bases, UNPARALLELED Group conducts mechanical simulation combined with the overall equipment load, optimizes the layout of base ribs and wall thickness to improve overall rigidity, and cooperates with a reasonable support scheme to weaken external vibration transmission. It reduces vibration transferred to the reference plate surface and guarantees reference stability during probe scanning and sensor sampling, lowering random errors of dynamic measurement.
Consistency of metrology traceability represents the core value of reference surfaces serving sensors and probes. Equipment factory calibration and regular on-site verification both require probe calibration based on the base plate surface. If regional deviations exist in the flatness of the reference surface, probe parameters calibrated at different positions will be inconsistent, and deviations will occur during cross-region workpiece inspection. In the finished product inspection stage, UNPARALLELED Group uses laser interferometers and high-precision electronic levels to conduct full-area grid sampling and mapping for plate surfaces and completely record the full-area plane contour, ensuring the whole plate uniformly reaches high flatness standards. All measuring tools can be traced back to national metrology institutions, guaranteeing the reference itself has traceability and making calibration results of sensors and probes credible and repeatable.
From semiconductor inspection and PCB precision inspection to new energy lithium battery inspection scenarios, sensors and probes keep upgrading toward higher resolution and faster sampling speed, raising requirements for reference carriers continuously. The more precise the probe accuracy, the higher the weight of errors brought by the reference. Relying on years of cooperation experience with metrology institutes and high-end equipment enterprises, UNPARALLELED Group continuously optimizes the whole system of granite base material selection, forming and inspection. It takes the stable high-flatness plate surface as the underlying geometric reference to carry various high-precision sensors and probes and builds a solid measurement foundation for global ultra-precision inspection equipment.