Parallelism

The choice of optical elements necessary for parallelism measurements depends on the selected measurement method: i.e. 3D or Wollaston. If 3D method is used then the linear optics plus right angle etalon should be used.

3D method

In this case the necessary components are:

  •  Laser Head
  •  Power Supply
  •  Linear Interferometer IL1
  •  Linear Retro-reflector RL1
  •  Right angle etalon RE3D
parallellizm

OPTICAL PATH SET UP FOR 3D PARALLELISM MEASUREMENTS-SCHEMATIC FOR AXIS 1.

parallelizm2

OPTICAL PATH SET UP FOR 3D PARALLELISM MEASUREMENTS-SCHEMATIC FOR AXIS 2.

 

Parallelism measurements based on the 3D method require optical elements IL1 and RL1 to be aligned along laser beam as shown in the figures above. The element RL1 should be moved. The beam should be directed to the perpendicular axis with the use of the right angle etalon RE3D.

Wallastone method

Wollaston parallelism measurements require optical elements WP2 and WRP2 to be aligned along laser beam as shown in the figure 11.3. The element WP2 should be moved first along Axis 1 and then along Axis 2. No right angle prism is necessary for this measurement.

parallelizm3

OPTICAL PATH SET UP FOR WOLLASTONE PARALLELISM MEASUREMENTS – SCHEMATICS

During parallelism measurements the usage of the air temperature sensor is recommended. Base temperature sensors do not have to be used.