Electrophotographic machine having a method and apparatus for measuring toner density by using diffuse electromagnetic energy
US5162874A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 24, 1990 |
| Grant date | Nov 10, 1992 |
| Priority date | — |
| Expiry date | Dec 24, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/55
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An electrophotographic apparatus having a densitometer, which measures material density located on a substrate by detecting and analyzing only a single diffuse electromagnetic energy signal reflected off of the density of material located on the substrate. Specifically, the apparatus must first be compensated for environmental and individual machine differences using a high density of the material. Moreover, once compensated, the apparatus is calibrated to determine the relationship between diffuse signals and material density. This relationship is calculated by sampling a clean substrate and low densities of the material. Once the relationship is determined, densities of material can be calculated given a corresponding diffuse signal. The calibrated and compensated density calculations enable accurate monitoring and adjustment of the electrophotographic apparatus color toner development systems.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.