Many applications could benefit from miniaturized systems to scan blood vessels behind the retina in the human eye, so called „retina scanning“. This reaches from access control to sophisticated security applications and medical devices. High volume systems for consumer applications require low cost and a user friendly operation. For example this includes no need for removal of glasses and self-adjustment, in turn guidance of focus and point of attraction by simultaneous projection for the user. A new system has been designed based on the well-known resonantly driven 2-d scanner mirror of Fraunhofer IPMS. A combined NIR and VIS laser system illuminates the eye through an eye piece designed for an operating distance allowing the use of glasses and granting sufficient field of view. This usability feature was considered to be more important than highest miniaturization. The modulated VIS laser facilitates the projection of an image directly onto the retina. The backscattered light from the continuous NIR laser contains the information of the blood vessels and is detected by a highly sensitive photo diode. A demonstrational setup has been realized including readout and driving electronics. The laser power was adjusted to an eye-secure level. Additional security features were integrated. Test measurements revealed promising results. In a first demonstration application the detection of biometric pattern of the blood vessels was evaluated for issues authentication in.

Date Published: 27 February 2015
PDF: 11 pages
Proc. SPIE 9375, MOEMS and Miniaturized Systems XIV, 937506 (27 February 2015); doi: 10.1117/12.2079468

Published in SPIE Proceedings Vol. 9375:
MOEMS and Miniaturized Systems XIV
Wibool Piyawattanametha; Yong-Hwa Park, Editor(s)