Many laser diodes do not emit their beams exactly perpendicular to their housings so when a module is manufactured that requires the housing for alignment the result is a laser diode module (LDM) that has so-called beam angular errors. The misalignment between the housing outside diameter and laser beam axis can be so extreme it becomes easy to see when the working LDM is rolled over a table, resulting in the beam oscillating up and down with each revolution of the housing instead of the beam describing a straight line.

When using an LDM to align one machine with another, for example, the module must have a defined, good-fitting housing from which the laser beam exits axially. This is the only way to ensure that the laser is suitable for alignment after suitable mechanical preparations have been made to the machines.

Another application includes the use of an LDM in the chuck of a turning lathe. The projected dot offers exact information on the alignment of the setup thereby offering a datum axis against which other assemblies may be aligned.

For other applications in this field of non-contact alignment LASER COMPONENTS offers the LT emitter precision module with specifications that include: laser alignment: less than 1mm deviation at a distance of 20 metres (10arc secs); housing: H6 mount, 30mm in diameter x 65mm in length; and operating voltage: 5 VDC or 24 VDC, reverse voltage protection.

This module may be operated without laser safety eyewear.