Visisize is Oxford Lasers’ flagship particle sizing system. It’s used by customers in diverse fields from agrochemical spray development to nuclear fuel reprocessing to the automotive industry. In 2009, I was responsible for repackaging the system to better suit industrial users. Prior to the redesign, the system was supplied in a trolley constructed from aluminium extrusion, which was costly and complicated to build, and didn’t have a good appearance. Furthermore, the package meant that the laser was incredibly difficult to service because it was deeply buried within the trolley and couldn’t be accessed easily. The liquid light guide that we used to deliver the laser light to the measurement head was also exposed to being tightly bent (meaning that its transmission efficiency was reduced).

Visisizer N60

The replacement trolley is based on a 19” rack mount. The system PC was switched to a rack mount version and the laser head was fitted in a drawer below it. Additionally, the light guide connection was changed to have a vertical launch rather than horizontal, which has two benefits. First, the light guide doesn’t hang with a tight bend radius near its input end, which improves launch efficiency and secondly, the downward beam reduces the risk of accidental laser exposure if the light guide should be disconnected whilst the laser is running because the beam will hit the floor rather than traversing the lab.

To further improve laser safety, I added a mechanical shutter that closes when the light guide is not connected. The shutter is spring loaded and further reduces the risk of accidental beam exposure.

All of the control electronics for the system timing and power distribution are mounted in the drawer, which makes the system very easy to service and maintain because all the components are accessible to the service engineer. The Visisizer N60 system has proved to be very popular with Oxford Lasers’ customers and it’s particularly gratifying to see the improvement with this revision.