The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 20, 2009
Filed:
Oct. 27, 2006
Joong-gwang Shin, Seongnam-si, KR;
Ki-ju Pak, Yongin-si, KR;
Jean-man Sur, Suwon-si, KR;
Samsung Electronics Co., Ltd., Suwon-si, Gyeonggi-do, KR;
Abstract
An apparatus to detect the remaining amount of developer in a developing unit is provided. The apparatus includes a light emitting prism and a light receiving prism placed opposite to each other in a developer store space of the developing unit and forming a light emitting path and a light receiving path, respectively. A light emitting element irradiates light through the light emitting prism, and a light receiving element receives a light signal through the light receiving prism. An antistatic agent is coated on a light emitting window of the light emitting prism and a light receiving window of the light receiving prism, respectively, to substantially prevent developer from attaching on the light emitting window and the light receiving window. Because the developer is not stuck on the light receiving window and the light emitting window to which the light signal is transmitted, an accurate light signal may be transmitted from the light emitting window to the light receiving window, thereby substantially preventing printing defects caused by detection errors from occurring.