Patent ID: 6414749
Filing Date: 2002-07-02
Classification: G06K

Abstract:
An uneven-pattern reading apparatus comprising:a detecting prism having a detecting surface on which an uneven pattern is placed, an incident surface upon which an incident light beam for illuminating the uneven pattern is incident, and an-emergent surface from which a light beam reflected from the uneven pattern on the detecting surface is emergent, angles between the respective incident, detecting, and emergent surfaces providing that the incident light beam is applied to the uneven pattern and the light reflected from the detecting surface is emergent from the emergent surface; incident-light-beam converging means for collimating or converging the incident light beam from a light source before incidence on the incident surface; an imaging device for detecting a reflected image emergent from said detecting prism; a converging optical system for converging the emergent light beam emergent from the emergent surface upon an imaging surface of said imaging device after collimating or converging the emergent light; and a processing device for identifying the uneven pattern on the basis of the image detected by said imaging device, wherein the imaging surface of said imaging device is located closer to an emergent surface side than a focusing position of said converging optical system.