High resolution Non-contact 3D Measurement System
STIL Optical Pen DUO
Feature / Measurement Principle / Specification
Feature
- 2 operating principles: Confocal Chromatic and White Ligth Spectral Interferometry
- 2 measuring modes: Distance and Thickness
- Compatible with all optical pens
- RS232/RS432 and ethernet
- Local user interface (LCD display and Keypad on the front pannel) for easy configuration
- Subnanometric resolution
- Vibration-free measurement
- Exceptional sub-nanometric resolution
- High signal to noise ratio
- Thin layer thickness measurement (min. measurable thickness: ~ 0.4 µm)
- Measurement of high aspect-ratio holes and scratches
Measurement Principle （Confocal Spectral Interferometry ）
The light from a white-light point source W passes through an interferometric
objective L and a reference plate R before it reaches the sample surface.
The superposition of the light beams reflected from the sample surface
and from the reference plate generates an interference phenomenon.
The reflected beams pass through the interferometric lens L in the opposite direction, and arrive at a pinhole P which filters out all light rays except those originating from the object point M.
The spectrometer S measures the channeled spectrum of the interference
signal.
The thickness of the air gap between the sample and the reference plate
can be extracted with sub-nanometric resolution from the spectral phase
of this spectrum.