A field-of-view controlling arrangement such as a privacy screen includes a single microprism or lenticular sheet having a plurality of sets of parallel surfaces that intersect to form prisms or lenticular structures, and in which field-of-view control is achieved by (i) for sheets made up of parallel...http://www.google.co.uk/patents/US6443579?utm_source=gb-gplus-sharePatent US6443579 - Field-of-view controlling arrangements
