Patent ID: 6369796
Filing Date: 2002-04-09
Classification: G06F,G06K,H04N

Abstract:
An apparatus for obtaining a difference image between object images corresponding to irradiated and non-irradiated states, comprising:a light emitter configured to irradiate an object with light; an area image sensor having imaging units constructed by a two-dimensional matrix of a plurality of light-receiving elements that perform photoelectric conversion, and a plurality of Charge Coupled Device (CCD) type charge transfer sections for transferring and outputting charges obtained by said imaging units; a controller configured to control charge transfer timings from the light-receiving elements to said CCD type charge transfer sections to alternately arrange charges received when said light emitter emits light and charges received when said light emitter does not emit light in a predetermined sequence in all or the individual CCD type charge transfer section of said area image sensor; a delay line configured to delay an output signal from said area image sensor by one horizontal scan time; and a difference circuit, one input of which is connected to said delay line, the other input of which is connected to said area image sensor, and which outputs a difference between two input signals.