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US 9,003,972 B2Granted
Reflection densitometer
AssigneeHewlett-Packard Development Company, L.P.
InventorsHenryk Birecki, William D. Holland, Omer Gila
Life of this patent
Estimating the term…
Abstract
A method for determining optical density is disclosed. A first measurement is taken on a white area of a substrate (402). A second measurement is taken on an area of the substrate printed with ink (404). A relative optical density of the ink is determined using the first and second measurements (406).
Claims13
A method, comprising:
- measuring a first optical density (OD) on a white area of a substrate;
- measuring a second OD on an area of the substrate printed with ink;
- determining a relative OD of the ink using the first OD and the second OD;
- determining an absolute OD of the ink by adding the relative OD of the ink to an absolute OD of the substrate;
- and
- controlling, by a printer, a printing process using the determined absolute OD of the ink.
3 more elements
An apparatus, comprising:
- at least one illumination source;
- illumination optics positioned to direct light from the at least one illumination source onto a target area;
- a detector positioned to collect light from the target area;
- detector optics positioned to focus light from the target area onto the detector;
- a controller coupled to the at least one illumination source and the detector and configured to:
- receive a measured first optical density (OD) when a white area of an object is in the target area, and receive a measured second OD when an area of the object printed with ink is in the target area,
- calculate a relative OD of the ink using the first measured OD and the second measured OD,
- calculate an absolute OD of the ink by adding the relative OD of the ink to an absolute OD of the object, and
- control a printing process using the calculated absolute OD of the ink.
6 more elements
Dependencies are inferred from the claim text.