An optical/digital incoherent image processing system for an extended depth of field

A severely defocused incoherent system has isolated zeros in its optical transfer function(OTF); therefore, an exact inverse filtering cannot be performed. It has been established that, by using an annular aperture in an optical system, the depth of focus can be extended. Isolated zeros in the OTF can therefore be avoided by choosing an annular aperture with a proper radius ratio. However, in the process of increasing the depth of focus of the system, this method results in a loss of image contrast. An annular pass filter can be used to restore this loss in contrast. A simple hybrid optical/digital image processing system in which a TV camera is coupled with an annular aperture is considered. The annular-pass filtering to compensate for the loss of contrast is performed by a digital computer. The experimental results are presented.

Name thesis:degree_name

M.S.

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Electrical Engineering

Department dc:contributor.department

Electrical Engineering

Grantor dc:publisher

Virginia Polytechnic Institute and State University

Year dc:date.issued

1985

Author dc:creator

• Motamedi, Masoud

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/10919/106043

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/106043