There are a total of one hundred seventy precision flat mirrors within the optical array at the Navy Prototype Optical
Interferometer (NPOI). During the build phase each mirror center is positioned in space relative to a primary fiducial.
Prior to nightly astronomy observations each mirror train, up to six trains containing ten mirrors each, are checked and
finely adjusted if necessary. The facilitation of diverse science programs and expanding capabilities at the NPOI require
reconfigurations of optical mounts. As part of this process, alignment of the reconfigured optical train is performed.
Similar tools and techniques are in use for each of these three processes. A light emitting diode (LED), mounted on a
motorized target arm is strategically attached to each mirror's mount for viewing the mirror's center point. A focusable
precision alignment telescope mounted in a precision v-block assembly is employed as the basic alignment tool. The
human eye is the detector. In this paper, we describe the current tools and techniques used at the NPOI to achieve the
requisite alignment tolerances and validations during the build, operations, and reconfiguration phases. We also discuss
the development of alignment tolerances, the deficiencies of the current tools and techniques, issues with digital imaging
and centroiding, and efforts to enhance, quantify, and validate the alignments.