Document illumination with Lambertian cavity

An arrangement for illuminating imaging and processing documents in a document-processing system wherein a large number of documents are transported past one or more imaging stations, each station having a prescribed respective imaging-site this arrangement projecting an imaging beam from prescribed source means to illuminate documents at each said station site, each said source means comprising:

• one or more sets of lamps, each set comprising one or more individual lamp means, in a respective integrating Lambertian cavity with associated imaging camera means;
• plus optical coupling means adapted to project the illumination of said lamp(s) to a respective imaging site;
• the lamp(s) being adapted to direct all their illumination to the inner wall of said cavity for reflection/diffusion/integration there, said wall being particularly adapted to integrate, reflect and diffuse all the light incident upon it to said coupling means in Lambertian fashion.

In a document-processing system wherein a large number of documents are rapidly transported past one or more imaging stations, each station having a prescribed imaging-site with means, projecting a respective illumination beam from prescribed source means to said site plus camera means and means coupling document images from said site to said camera means;

• each said source means comprising a Lambertian integrated cavity with one or more sets of lamps therein and having a Lambertian reflecting/diffusing inner cavity-wall, being adapted to project, through an associated slit, a highly-diffused, highly uniform illumination beam to a respective imaging site;
• and each said image coupling-means comprising a mirror or like reflective means to receive and direct said image through said Lambertian cavity by means of slits provided therein to said camera means.

An arrangement for illuminating, imaging and processing documents in a document-processing system wherein a large number of documents are rapidly, continuously transported past one or more imaging stations, each station having a prescribed camera means and light source means comprising a hollow cylindrical Lambertian integrating vessel which houses one or more light sources and projects a highly-uniform, yet highly diffuse illumination-beam, while admitting light reflected from said documents to said camera means, yet masking said sources from direct view to said camera means and said documents.

In a document processing system wherein a large number of documents is rapidly transported past one or more imaging stations, each station having a prescribed imaging-site, illuminated by a respective illumination beam from prescribed source means;

• each said source means comprising a hollow cylinder cell with one or more lamps therein and having Lambertian reflecting/diffusing, integrating inner walls, and adapted to project, through an associated slit and optical guide means, adapted to conduct a highly-diffused illumination beam to the respective imaging site and a reflected image beam back;
• plus camera means adapted to intercept said image beam via said cylinder, all said means for each said station being housed and sealed in common housing means.

A document-processing apparatus having at least one camera means for at least one associated imaging site, each said site being illuminated by a beam from a respective source means, each source means comprising a cylindrical Lambertian cell having reflective/diffusing, integrating Lambertian inner walls and containing one or more lamp means, while also having an illumination-aperture and associated optical guide means adapted to conduct light reflected from said walls to illuminate its respective imaging site with a high-intensity, highly-diffuse beam, and to conduct reflected light back to said camera means via said Lambertian cell, all elements for each said site being housed and sealed in common housing means.

An arrangement for illuminating, imaging and processing documents in a document-processing system wherein a large number of documents is rapidly transported past one or more imaging stations, each station having a prescribed source means comprising a hollow cylindrical Lambertian integrating cell which projects a highly-uniform, yet highly diffuse illumination-beam;

• optical aperture/guide means coupling said cell and its station, and camera means in optical communication with said aperture/guide means to receive images reflected from the documents, all said elements being sealed in common housing means.

In a document processor, illumination means for documents at a prescribed illumination-site comprising housing means with an integrating Lambertian cavity having one or more lamp means therein, having inner cavity walls made to reflect, diffuse and integrate the light from said lamp means, having a prescribed illumination-aperture means to direct said integrated, reflected, diffused light to said site, yet shielding all said lamp means from directly viewing said site.