Optical scanning device and image forming apparatus including the same

An optical scanning device that irradiates an image carrier with laser light so as to form an electrostatic latent image, the optical scanning device comprising:

• a housing in which an emission port for the laser light is formed to extend in a main scanning direction of the laser light so as to correspond to the image carrier;
• a transmissive member that is transmissive with respect to the laser light, extends in a main scanning direction of the laser light, and seals the emission port for the laser light;
• a linear member that is stretched in a loop on the housing;
• a drive portion that drives the linear member to travel in a predetermined direction;
• a guide rail that is juxtaposed with the emission port and extends in an extending direction of the transmissive member;
• a cleaning holder that is fixed to the linear member and, when the linear member is driven to travel by the drive portion, moves over the transmissive member along the guide rail;
• a cleaning member that is fixed to the cleaning holder and slides with respect to the transmissive member along with movement of the cleaning holder to thereby clean the transmissive member;
• a detection portion that is disposed on one side in the extending direction of the transmissive member so as to detect that the cleaning holder has reached one end part of a movement path of the cleaning holder;
• and
• a control portion that controls driving of the drive portion,
• wherein
• the detection portion includes:
• a light emitter that emits light in a juxtapositional direction of the transmissive member;
• and
• a light receiver that receives light emitted from the light emitter, and is disposed along the housing such that longitudinal directions of the light emitter and the light receiver are parallel to a movement direction of the cleaning holder,
• the cleaning holder includes a light blocking portion that is located, when the cleaning holder reaches the one end part of the movement path thereof, between the light emitter and the light receiver so as to block light emitted from the light emitter, with a gap formed between the light blocking portion and the housing, and
• the housing includes a light leakage prevention portion formed between the light emitter and the light receiver.