When measurement accuracy drops below ±10 µm, perspective error becomes fatal. Telecentric lenses send nearly parallel rays to the sensor, locking magnification even when parts shift toward or away from the optic. That eliminates parallax and edge taper, producing truly orthographic views
Core advantages:
- Dimensional integrity – Pixel-to-millimeter scaling stays constant across depth.
- Minimal distortion – Typically < 0.02 %, enabling sub-pixel edge fits.
- Superior depth budget – Objects ±5 mm off the nominal plane remain within 1 % size error.
Trade-offs include larger barrels, longer WDs, and higher cost. Deploy telecentrics for connector pin height, thread inspection, or pick-and-place calibration where every micron counts.
