A document (10) is covered by a laminate (13) comprising a layer of
microspheres (16) over an adhesive layer (14) covering a source image
(12) such as a photograph, printed matter, or a bar code arranged on a
substrate (11). Light impinging on the document (10) is split by the
optical properties of the microspheres (16) and underlying specular
reflectors. The remaining light passes through the microspheres (16),
through the adhesive layer (14) and strikes the substrate (11) or source
image (12) on the document (10), and is reflected (18) and scattered
(20). Alternatively, the laminate (13) can comprise a plain or clear
layer of polyester without microspheres over the adhesive layer (14).
Light impinging on the laminate (13) passes through the polyester and
laminate (14) to strike the substrate (11) or source image (12) where it
is reflected and scattered. A first light source (24) directs light to
the document (10). A second light source (26,27) directs light towards a
beam splitting mirror (23) which reflects the light to the document (10).
The light turning properties of the mirror (23) produce a light source
which appears to an image receiver (40) as being returned from the
surface of the document (10) at an angle of less than 1.degree.. The
image receiver (40) passes a signal via line (32) to a personal computer
(41) which processes the received information. Such processing is to
establish whether the document (10) includes a retroreflective laminate,
a plain polyester laminate, or neither. Additionally, further processing
can establish whether the document (10) has been tampered with, altered,
or forged.