An integrated optical position-sensitive detector with digital output and error correction

Characterisation of 1D opto-electronic sensors and their application to angular self-centring probes for machine-tool verification

“…The background light also increases the noise in the signal. Some ways to electronically eliminate this influence have been developed in the past [15,16]. Nevertheless, the background light should not be a problem for the application of the PSD to a self-centring probe, because the probe will be closed and external light will not come into it.…”

“…Noise is a very important topic in these sensing systems because it affects the resolution, dynamic range and signalto-noise ratio (SNR) with the consequent lack of repeatability problems [14][15][16]. In order to analyse its influence on the measuring system, several repeatability tests were carried out by placing the LED fixed over the PSD and studying the influences on the point measured by the PSD by changing the electronic used [17].…”

Digital output silicon optical sensors

“…This approach reduces the number of additional electronic components to a minimum, reduces the cost of the processing system, and improves the reliability. Successful realizations of such kind of sensors for optical and mechanical sensing are well known [3,4], as well as commercial sensors with on-chip signal processing, for instance, we can mention the optical sensor KPDC0028EA, from Hamamatsu Photonics Inc., with a light-to-frequency conversion, and the temperature sensor SMT 160-30, from Smartec, with a digital (pulse-width modulation) output.…”