Rotation-free Centration Measurement Improves Speed and Flexibility
For two decades, the OptiCentric® measurement systems manufactured by TRIOPTICS have been regarded as the standard for the centration measurement of optical single lenses and lens systems. With their sophisticated optics and mechanics, intuitive software and patented inspection algorithms, the systems achieve measurement results with the highest precision. However, this requires that the samples be measured on a precision rotation bearing. The use of such a rotation bearing typically necessitates a vertical measurement arrangement.
"These limitations are a problem for two groups of our customers," explains Product Manager Dr. Patrik Langehanenberg. "First, those who want to inspect high-quality lenses in which floating elements (e.g. image stabilizers) are installed. Here, the positioning of the single lenses in a vertical inspection situation is not the same as their position in the subsequent application. The second group is customers who want to use centration inspection in volume production where the conventional process with its rotation is just too slow." Faced with this challenge, engineers at TRIOPTICS have now developed a centration inspection process that can perform a centration measurement without rotation and regardless of the sample position – OptiCentric® Linear.
The special feature of this inspection method lies in its use of the linear path of motion of the autocollimator focus – not the rotation axis – as the reference axis for measurement. The positions of the sample’s centers of curvature are measured in relation to this focal position. "Deviations from the perfect linear path of motion of the focus are balanced at our plant by means of calibration. This makes it possible to achieve accuracies of ≤ 1 microns during centration error measurement," Langehanenberg says.
This new measurement technology significantly increases the degree of freedom of measurement. This makes the orientation of the measurement setup freely selectable, and it can also be horizontal. The lack of rotation ensures the required speed for performing quality inspections in volume production. "Reactions to this new procedure have all been positive," Langehanenberg reports after Optatec in Frankfurt. "We will remain highly flexible in the further development of this product and can work with our customers to create solutions that go beyond our initial idea. The opportunities offered by the OptiCentric® Linear are by no means exhausted."