Position Sensors

Optical sensors for measuring position and motion

Position-Sensing System Configuration Guide

The key to understanding optical position sensing systems is to understand the sensors which form the heart of such systems. These fall into two basic categories: segmented and continuous.

Segmented sensors consist of two or more distinct photosensitive elements separated by a small gap. These highly-sensitive devices are best used as nulling and centering devices. Their useful range is limited by the illumination spot size. This category includes Quadrant and BiCell type sensors.

Continuous sensors consist of a single photodiode, without any gaps. These devices are best for measuring a light spot's movement over a wide range (greater than the spot size). This category includes duo-lateral, tetra-lateral, and superlinear types.

Further explanation is offered in the UDTi position sensing tutorial (see link above).

Position Sensor/Instrument Compatibility Table
SENSOR SENSOR
TYPE 301DIV 501 431 531
1232 Tetra-lateral X X
1233 Tetra-lateral X X
1237 Tetra-lateral X X
1238 Tetra-lateral X X
1239 Tetra-lateral X X
1240 Quadrant X X
1241 Tetra-lateral X X
1242 Quadrant X X
1243 BiCell X X
1245 Quadrant X
1248 Duo-lateral X
1250 Duo-lateral X
1252 Superlinear X X
1262 Quadrant X