Unified Optical Scanning Technology

Chapter 4.2 - Scanner Devices and Techniques: High Inertia Scanning

4.2 HIGH-INERTIA SCANNING

High-inertia scanning typically entails motion of a significant mass. When properly balanced, such action often provides a bonus by suppressing perturbation of the desired scan function. When operating in continuous rotation, it benefits also from nonoscillatory and nonreciprocating action to render a unique combination of high speed and high uniformity of data point transfer. Rotational components, which include the polygons and holographic scanners, can form highly ordered data points at rates extending into the hundreds of megapixels per second and can be designed to provide pixel spatial uniformities (along scan) that challenge the instrumentation for measurement to such high accuracy.

The linear translational components, such as the traverse mechanisms and position stages, derive position servo feedback typically from linear optical encoders. They can provide extremely high-accuracy linear motion at substantive velocities. Although these speeds are outstripped by the flat-fielded rotational scanners rendering linearized scan, the capacity of the translation stages for moving heavy loads and extremely low f-number objective optics allows traversing extremely small pixels at a high data rate. For example, imaging 1-μm spots at a velocity of 2m/s represents a data rate of 2 mpixels/s. However, transports that form the useful scan in one direction can be required to retrace at a much higher speed to form a favorable duty cycle (Section 4.2.3). This burdens decelerating and reaccelerating massive moving members, limiting traverse mechanisms to relatively slow scan retrace periods.

 

UNLIMITED FREE ACCESS TO THE WORLD'S BEST IDEAS

SUBMIT
Already a GlobalSpec user? Log in.

This is embarrasing...

An error occurred while processing the form. Please try again in a few minutes.

Customize Your GlobalSpec Experience

Category: Dimensional and Profile Scanners
Finish!
Privacy Policy

This is embarrasing...

An error occurred while processing the form. Please try again in a few minutes.