Alignment telescopes are integral to most, if not all, optical sciences departments, equipment manufacturers, and optical integration houses. Typically alignment telescopes are a refractive type. Two lenses are displaced from one another within an optical path to focus on an observed image. Thus they can align objects along a common axis. In addition, some types of alignment telescopes have auto collimation features built into them. This feature allows them to measure angular error of reflective objects along the line of sight of the telescope.
USPTO Backgrounds
USPTO Backgrounds