Operation and design of photoelectric sensors

OADM is a range of laser distance sensors with products covering the measuring range from 16 mm to 13 m. The compact sensors with integrated microcontrollers produce an accurate output signal proportional to the measured distance. Intelligent internal signal analysis permits the sensor to operate accurately regardless of the color and most surfaces. The sensor can always be easily and precisely aligned with the visible spot of light. Distances to rough surfaces can be reliably measured by using a fine laser line in place of the laser spot, so that a wider area is monitored.

Typical applications

This family of sensors, with its wide selection of measuring ranges, can be used in many applications. Typical applications are:

  • Applications in which the production process is continuously monitored by the sensor to detect slow changes at an early stage and thereby achieve a reduction of rejects and costs.
  • Automation of test points and test equipment permits increased productivity.
  • Automation of format settings permits multifunctional machines and rapid, precise reconfiguration.
  • In some other applications, objects with rough and uneven surfaces must be measured.

Sometimes, the surface of the object even has small holes or gaps. Such objects can be easily measured using a laser line optical system, which supplies a fine laser line in place of a focused laser beam.

Characteristics and advantages

Response time
Measuring cycles as short as 0.9 ms permit accurate measurements even on moving parts.

Integrated microcontroller
The integrated microcontroller makes an external processing device unnecessary and makes it simple to place the sensor wherever it is needed.

High resolution and linearity
By the use of a photodiode line in triangulation sensors, a very high linearity of ±6 μm is achieved at a resolution of up to 2 μm (measured on matte white ceramic).

Laser spot or laser line
Distances, even to rough surfaces, are reliably measured by using a laser line instead of the laser spot.

Any surface
Intelligent signal processing improves the measurements made on critical surfaces.

Teach-in function
The measuring range can be adjusted within the maximum measuring range by the user with the Teach-in button or via the Teach-in cable. The analog output has its full span within this taught-in range. The factory setting is the maximum measuring range. The taught-in range has a minimum extent. The resolution and linearity change when the measuring range is changed. The closer the furthest point of the measuring range is to the sensor, the better the resolution.

Synchronization/hold function
The measurements of several sensors can be synchronized using the sync input, or the last value can be held and the laser diode switched off.

Insensitivity to external light
An algorithm makes the sensor insensitive to external light sources.