US 5,684,530 A · Continuous diffuse illumination method and apparatus

Abstract

The method and apparatus for providing an elongate linear continuous, uniformed, diffused lighting environment for use in conjunction with an electronic line scanner, a photo-copier or a machine vision system, particularly for inspection and reproduction of specular surfaces such as documents or art work containing highly reflective areas on the surface thereof and other shiny surfaces. The linear illumination device includes at least one elongate source of light, illuminating a primary diffuser, to provide a primary diffused light source and a secondary elongate source of light illuminating a secondary diffuser to provide a secondary diffused light source supplied substantially along an observation plane of the illumination device. The two sources provide uniformly diffused lighting of an elongate strip of an object located at the object observing location to facilitate accurate viewing of a desired elongate portion of the object to be observed.

Claims20

Dependent claims

An elongate diffuse illumination device for uniformly illuminating a desired elongate linear portion of an object when observed along an observing plane extending transversely of an object observing location, said diffuse lighting device comprising:

at least one elongate surface, for supplying diffused light, being located adjacent an elongate opening through which the observing plane passes, said surface being arranged to supply primary diffused light to provide said uniform illumination of the desired linear portion of the object when placed at the observing location and viewed along said observing plane, except for portion of the object effected by the elongate opening;
a source for producing secondary diffused light to illuminate the desired portion of the object effected by the elongate opening;
and
an elongate partially reflective mirror for supplying said secondary diffused light along the observing plane to uniformly illuminate the elongate portion of the object effected by the opening to produce, when primary diffused light simultaneously illuminates said elongate surface, said uniform illumination of the desired portion of the object when viewed along the observing plane.

1 more element

A method for uniformly illuminating, via a elongate diffuse illumination device, a desired portion of an object when observed along an observing plane extending transversely of an object observing location, said method comprising the steps of:

providing an elongate opening adjacent at least one elongate surface for supplying light, and passing the observing plane through said elongate opening;
arranging said at least one elongate surface to supply primary diffused light to provide said uniform illumination of the desired portion of the object when placed at the observing location and viewed along said observing plane, except for a portion of the object effected by the elongate opening;
providing a source of secondary diffused light to illuminate the desired portion of the object;
and
supplying said secondary diffused light, via a partially reflective elongate mirror, along the observing plane to uniformly illuminate the portion of the object effected by the opening to produce, when primary diffused light simultaneously illuminates said elongate surface, said uniform illumination of the desired portion of the object when viewed along the observing plane.

2 more elements

Dependencies are inferred from the claim text.

Continuous diffuse illumination method and apparatus

Life of this patent

Continuous diffuse illumination method and apparatus

Life of this patent

Abstract

Claims20