Pattern projection device for use with strobo-laryngoscope for obtaining e.g. vocal length to evaluate creature vocal health condition, has source, where pattern dimension remains constant independent of distance between source and surface

摘要

The device (100) has a light source (102) e.g. laser diode, for emitting a light beam (L) for producing a pattern e.g. circular pattern, at an observation surface (S). A dimension of the pattern at the surface remains constant independent of a distance (D) between the source and the surface. A beam splitter and a reflection mirror are provided in a path of the light beam coming out from the source. The splitter divides the light beam into partial beams. The mirror reflects the light beam in a direction of the surface. A fastening device includes a carrier part for fastening the source. An independent claim is also included for a method for dimension computation.