Scanning heads
AssigneeQuad/Tech UK Ltd.
InventorTrevor Montgomery
Life of this patent
Estimating the term…
Abstract
A scanning head for use in a register mark detection apparatus for detecting register marks on a web during relative movement between the web and the scanning head. The scanning head comprises an optical sensor and a first optical mask spaced from the optical sensor and having an aperture therethrough to define the viewing footprint of the optical sensor. In some embodiments, the scanning head also includes a second optical mask in series with the first optical mask. The scanning head is versatile and capable of operating with high sensitivity and accuracy even with low contrast media, including with embossed or relief marks, or for fold-line registration or with translucent media.
Claims27
A scanning head suitable for use with a printing press in a register mark detection apparatus for detecting register marks on a substrate, the scanning head comprising:
- an optical sensor;
- and
- a first optical mask spaced from the optical sensor, the first optical mask having an aperture therethrough to define the viewing footprint of the optical sensor.
A scanning head suitable for use with a printing press in a print register mark detection apparatus for detecting register marks on a web surface, the scanning head comprising:
- an optical sensor;
- a first optical mask spaced from the optical sensor, the first optical mask having an aperture therethrough;
- and
- a second optical mask with an aperture in series with the first mask, the apertures of the first and second masks together defining the viewing footprint of the optical sensor.
A printing press including a print register mark detection apparatus for detecting register marks on a printed paper substrate, the print register apparatus comprising:
- a scanning head comprising:
- an optical sensor,
- a first optical mask spaced from the optical sensor, the first optical mask having an aperture therethrough,
- a second optical mask having an aperture therethrough, the aperture of the second optical mask in series with the aperture of the first optical mask, the apertures of the first and second optical masks together defining the viewing footprint of the optical sensor, and
- a light source for illuminating the paper substrate, the light source being a solid state, low power light source.
Dependencies are inferred from the claim text.