Most laser scanners applications require a linear scanning function, i.e., a constant scanning speed. One of the possible
and simplest methods to achieve this – for both scanners with rotational (i.e., polygonal) or oscillatory (i.e.,
galvanometer) mirrors – is to increase the distance between the mirror and the scanned plane. In order to achieve this, we
propose and study a simple and low-cost optical configuration with two plane mirrors set at a certain adjustable angle.
The multiple reflections of a laser beam on the two mirrors are considered, the number of images produced is deduced,
and the total optical path is obtained. The device is considered for a dimensional measurement application, usually called
an optical micrometer - in a set-up which includes the two angular mirrors between a laser scanner with oscillatory or
rotational mirrors and its objective lens. This simple device increases the path of the laser beam between the scanning
mirror and the lens in a compact construct. The linearity of the scanning function is thus increased, while the total size of
the system is reduced – with regard to other possible set-ups. A multi-parameter analysis is proposed and briefly pointed
out with regard to the characteristics of the system.