Polygon mirror, light scanning unit employing the same, and electrophotographic image forming apparatus
AssigneeSamsung Electronics Co., Ltd.
InventorSu-whan KIM
Life of this patent
Estimating the term…
Abstract
A polygonal rotating mirror, a light scanning unit employing the polygonal rotating mirror, and an electrophotographic image forming apparatus are shown. The polygonal rotating mirror is employed in the light scanning unit for scanning a light beam and includes a plurality of reflective surfaces enclosing outer side surfaces thereof. One of the plurality of reflective surfaces is a reference surface, a region of the reference surface where a light beam for a synchronization signal is to be incident is formed as a non-reflective region, and regions of the remaining reflective surfaces of the plurality of reflective surfaces where a light beam for a synchronization signal is to be incident, are formed as reflective regions.
Claims18
A polygonal rotating mirror employed in a light scanning unit for scanning a light beam, the polygonal rotating mirror comprising:
- a plurality of reflective surfaces enclosing outer side surfaces thereof,
- wherein one of the plurality of reflective surfaces is a reference surface, a region of the reference surface where the light beam for a synchronization signal is to be incident is formed as a non-reflective region, and regions of the remaining reflective surfaces of the plurality of reflective surfaces where the light beam for the synchronization signal is to be incident, are formed as reflective regions.
A light scanning unit comprising:
- a light source unit which emits a light beam;
- a polygonal rotating mirror including a plurality of reflective surfaces enclosing outer side surfaces thereof, which deflects and scans the light beam emitted by the light source unit in a main scanning direction;
- and
- a synchronization detecting sensor which receives a portion of the light beam reflected by the polygonal rotating mirror and which generates a first horizontal synchronization signal,
- wherein one of the plurality of reflective surfaces is a reference surface, a region of the reference surface where the light beam for a synchronization signal is to be incident is formed as a non-reflective region, and regions of the remaining reflective surfaces of the plurality of reflective surfaces where the light beam for the synchronization signal is to be incident, are formed as reflective regions.
An electrophotographic image forming apparatus comprising:
- a light scanning unit which scans a light beam, wherein the light scanning unit comprises:
- a light source unit which scans a light beam;
- a polygonal rotating mirror including a plurality of reflective surfaces enclosing outer side surfaces thereof, which deflects and scans the light beam emitted by the light source unit in a main scanning direction;
- and a synchronization detecting sensor which receives a portion of the light beam reflected by the polygonal rotating mirror and which generates a first horizontal synchronization signal, wherein one of the plurality of reflective surfaces is a reference surface, a region of the reference surface where the light beam for a synchronization signal is to be incident is formed as a non-reflective region, and regions of the remaining reflective surfaces of the plurality of reflective surfaces where the light beam for the synchronization signal is to be incident, are formed as reflective regions, and
- a video signal processor comprising a second horizontal synchronization signal generating unit which counts a synchronization signal offset upon receiving the first horizontal synchronization signal from the synchronization detecting sensor and which a second horizontal synchronization signal regarding the reference surface, and a video controller which transfers video data to the light scanning unit based on the first and second horizontal synchronization signals.
Dependencies are inferred from the claim text.