TH6i | Optical sensor for seam tracking on butt joint with 0-gap

The TH6i is designed for optical seam tracking in automated welding processes using an arc or laser. The active seam recognition can detect the position of the workpiece and ensure that the tool is positioned accurately.

TH6i | Optical Sensor for Seam Tracking on butt joint with 0-gap

TH6i | mounted

Function description

The TH6i sensor scans the seam shape along the joint without actually touching it and transmits information including gap dimensions, joint edge offset and positioning of the tool relative to the workpiece surface to the robot controller. Integrated extraneous light filtering ensures smooth operation even in the area close to the process. Efficient signal analysis ensures reliable detection, especially on reflective surfaces.

Areas of application

  • Automated production processes like welding etc.


  • High reliability by use of state-of-the-art camera technique
  • Approved with high reflective surfaces as stainles steel or aluminum
  • Three laser lines: thus excellent stability during the acquisition of measurement data
  • Simple to operate


  • Seam tracking for standard joint types, specially on butt joint with 0-gap to correct device tolerances
  • Applicable on all popular and also high reflective material surfaces.
  • Immune to electromagnetic effects (EMI)
  • Not sensitive to electrical fields
  • Optical filters used to minimize sensitivity to extraneous light
  • Splash guard with integrated safety glass cleaning
  • Splash-proof housing
  • Safety-glass quick-change drawer
  • Integrated air cooling for the sensor
  • Interfaces to all popular robot controller
  • Universal analog / digital machine interface available

Further product information

  • integrated air flushing of protective glass
  • integrated cooling by air
  • working temperature +10°C up to +45°C
  • box splash water protected (IP64)
  • easy and rapid exchange of protective glass

Measuring lines3
Dimensions (W x H), in mm15 x 24
Measuring frequency60Hz
Resolution in the TCP, in Y35 μm/pixel
Resolution in the TCP, in Z95 μm/pixel
Operating temperature+10°C to +45°C
Laser protection class3
RIP protection degree (with plugged-in connectors)IP64
Dimensions (L x W x H), in mm70 x 40 x 191
Working distance sensor bottom (z = 0 mm) in mm150
Working distance sensorbackplane (x = 0) in mm10
Working distance in Y in mm (at z = 0 mm)+/-7
Working distance in Z (at y = 0 mm) in mm+/-12
Working distance in Y (at z = -12 ) in mm+/-6,5
Working distance in Y (at z = 12 ) in mm+/-7,5

Contact us


Sales & Customer Support

phone +49 - 30 - 91 20 74-346

fax +49 - 30 - 91 20 74-333



Technical Service

phone +49 - 30 - 91 20 74-311

fax +49 - 30 - 91 20 74-333