With the DOAL's coaxial (on axis) illumination, light rays reflect off a beam splitter directly on to an object at nearly 90°. With this coaxial lighting approach, specular surfaces perpendicular to the camera appear illuminated, while surfaces at an angle to the camera appear dark. Non-specular surfaces absorb light and appear dark.

The new DOAL-50 V2 (Version 2) expands application capabilities. Using the same on axis lighting technique, the DOAL-50 V2 delivers up to twice the light intensity of first generation DOALs. This high intensity coaxial light enables applications that were previously too intensity-dependent for beam splitter derived on axis lighting techniques.

Additionally, the V2 DOAL's fan-free design results in a quieter, more reliable unit suitable for environments where airflow disruptions are not allowed (e.g. clean rooms) and where air born dust penetration threatens the life of fan cooled devices.