Image input device with dust detector
AssigneeMinolta Co., Ltd.
InventorsShoji Imaizumi, Keisuke Hashimoto
Life of this patent
Estimating the term…
Abstract
An image input device identifies what part of the optical input system needs cleaning when there is dust or other foreign matter in the optical input system. This image input device has an image noise position detector for capturing image data from a scanner, and detecting the main scanning address of noise information corresponding to image noise present in the image data; a focus calculator for calculating focus information around the main scanning address detected by the image noise position detector; focus information storage for storing focus information for each subscanning line; and a foreign matter position determining circuit for determining the location of foreign matter on the scanner based on the focus information stored in the focus information storage.
Claims17
An image input device comprising:
- an optical system projecting an image to be captured;
- a sensor capturing the image projected thereon by the optical system and disposed in an optical path of the optical system, said sensor comprising a plurality of picture elements;
- a first controller detecting noise in an image signal outputted from the sensor and identifying one of the picture elements of the sensor corresponding to the noise;
- and
- a second controller identifying in the optical path a location of a substance causing the noise detected by the first controller.
An image input device comprising:
- a sensor having a plurality of picture elements arranged in a main scanning direction;
- an optical system for projecting onto the sensor an image to be scanned,
- said optical system moving in a subscanning direction orthogonal to the main scanning direction to sequentially project the image onto the picture elements of the sensor, and
- comprising a plurality of optical elements configured so that a distance between the optical elements changes as the optical system moves in the subscanning direction;
- a first controller detecting noise in an image signal outputted from the sensor and identifying a picture element of the sensor corresponding to the noise;
- and
- a second controller identifying one of the optical elements which has a substance causing the noise based on a change in image signal outputted from the identified picture element when the optical system moves in the subscanning direction.
A detection method for detecting a location of a substance disposed in an optical system, said method comprising:
- projecting an optical image onto a sensor by the optical system;
- capturing the projected optical image by the sensor;
- detecting noise due to the substance in an output signal from the sensor based on the captured optical image;
- identifying one of picture elements of the sensor corresponding to the noise;
- and
- determining a location in an optical path of the optical system of the substance causing the noise.
A detection method for detecting a location of disposed in an image input device, said method comprising:
- projecting an optical image onto a sensor by an optical system through an intervening glass for holding an original document;
- capturing the projected optical image by the sensor;
- detecting noise due to the substance in an output signal from the sensor based on the captured optical image;
- identifying one of picture elements of the sensor corresponding to the noise;
- and
- determining a location in an optical path of the optical system of the substance causing the noise.
Dependencies are inferred from the claim text.