Exposed Linear Encoders

Heidenhain Exposed Linear EncodersExposed linear encoders are designed for use on machines and installations that require especially high accuracy of the measured value.

Typical applications include:

  • Measuring and production equipment in the semiconductor industry
  • PCB assembly machines
  • Ultra-precision machines
  • High-accuracy machine tools
  • Measuring machines and comparators, measuring microscopes, and other precision measuring devices
  • Direct drives

Mechanical Design

Exposed linear encoders consist of a scale or scale tape and a scanning head that operate without mechanical contact. The scale of an exposed linear encoder is fastened directly to a mounting surface. The flatness of the mounting surface is therefore a prerequisite for high accuracy of the encoder.


Heidenhain Linear Encoder

Absolute Measuring Method

With the absolute measuring method, the position value is available from the encoder immediately upon switch-on and can be called at any time by the subsequent electronics.

Incremental Measuring Method

With the incremental measuring method, the graduation consists of a periodic grating structure. The position information is obtained by counting the individual increments (measuring steps) from some point of origin. Since an absolute reference is required to ascertain positions, the measuring standard is provided with an additional track that bears a reference mark.