Patent ID: 7881624
Filing Date: 2011-02-01
Classification: G03G

Abstract:
1. A developer cartridge, comprising: a cartridge body comprising a developer discharge port; a remaining developer detecting unit arranged in proximity of the developer discharge port; and an agitating unit rotatably arranged inside the cartridge body to convey the developer accommodated in the cartridge body toward the developer discharge port, wherein the remaining developer detecting unit comprises: a first optical guide comprising a light entry portion arranged on one end to face a light emitting unit of an optical sensor arranged outside of the developer cartridge, and a first light transfer surface formed on the other end; and a second optical guide comprising a light exit portion arranged on one end to face a light receiving unit of the optical sensor, and a second light transfer surface formed on the other end, wherein the first and second light transfer surfaces are arranged to face each other at a predetermined distance from each other with the first and second light transfer surfaces being located inside the cartridge body, the first optical guide comprising one or more reflective surface to reflect the light beam emitted from the light emitting unit towards the second light transfer surface via the first light transfer surface, and the second optical guide comprises one or more second reflective surface to reflect the light beam received at the second light transfer surface towards the light exit portion.