Position sensitive detectors. Spatially-resolved photodiodes measure the position of a light spot. The bandwidth and resolution of so-called position sensitive detectors (PSDs) are unmatched.
PSDs as alternative to scanning systems.
The PSD arrays from SiTek are a fast and inexpensive alternative to conventional scanning systems.
For distance measurements based on PSDs the triangulation method is used, which is extremely precise. Here a well-collimated laser or LED beam is directed at a sample surface, and the reflected light is detected using position-sensing detectors.
The beam strikes the individual position-sensing detector at a certain spot, and this position provides the desired information regarding distance. The array, on the other hand, allows for fast and safe execution of scan tasks when used together with line optics.
Scanning is extremely fast because the rise time of the individual PSD elements is less than 100 ns. Deviation of the PSD from its positional linearity is a maximum of 0.2%.
Sixteen-segment components are available as standard PSD arrays. Customer-specific designs of all types are available upon request.