Toner concentration sensor
US4551004A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 24, 1984 |
| Grant date | Nov 5, 1985 |
| Priority date | — |
| Expiry date | Aug 24, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/0849
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention is an apparatus for monitoring toner concentration on a photoreceptor surface. The apparatus includes a light emitting diode, the phototransistor, a beam splitter, and a lens disposed between the beam splitter and the photoreceptor surface to collimate the light beam between the lens and the photoreceptor surface. A portion of the light emitted from the LED is transmitted through the beam splitter and the lens to the photoreceptor surface. Collimated light is reflected from the photoreceptor surface back through the lens and reflected from the beam splitter to the phototransistor. The output signal from the phototransistor because of the incident and reflected collimated light is independent of the distance of the lens from the photoreceptor surface. Alternately, a second lens is disposed between the beam splitter and the phototransistor to enhance overall resolution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.