Optical Scanning Device and Image Forming Apparatus Equipped with the Same
An optical scanning device includes a light source for emitting first light beams, a deflecting unit that deflects the first light beams as second light beams having scanning lines that are substantially arc shaped, a scanning lens disposed in a light path of one of the second light beams, and a light-blocking member interposed between the deflecting unit and the scanning lens. The light-blocking member blocks reflected light generated from the one of the second light beams when the second light beam enters the scanning lens. The light-blocking member protrudes toward the second light beam path along at least a scanning area of the second light beam, and includes a protruding edge section curving in substantially a same arc shape as the scanning line.
1 . An optical scanning device comprising:
alight source configured to emit a plurality of light beams as first light beams,
a deflecting unit configured to deflect and scan the first light beams emitted from the plurality of light sources as second light beams having a scanning line that is substantially arc shaped,
a scanning lens disposed in a light path of at least one of the second light beams deflected and scanned by the deflecting unit, and
a light-blocking member interposed between the deflecting unit and the scanning lens;
wherein the light-blocking member is configured to (i) block reflected light generated from the at least one second light beam when the at least one second light beam enters the scanning lens, (ii) protrude toward the scanning line of the second light beams along at least a scanning area of the second light beams, and (iii) include a protruding edge section closest to the scanning line and curved in an arc shape.
2 . The optical scanning device according to claim 1 , wherein the protruding edge section has substantially the same arc shape as the scanning line of the second light beams.
3 . The optical scanning device according to claim 1 , wherein the scanning lens comprises a pair of scanning lenses facing each other with the deflecting unit interposed between the pair of scanning lenses.
4 . The optical scanning device according to claim 1 , wherein the first light beams enter the deflecting unit in a sub-scanning direction at different angles.
5 . The optical scanning device according to claim 4 , wherein at least one of the first light beams enter from above with respect to the deflecting unit, and the at least one second light beam is deflected and scanned downward with respect to the deflecting unit.
6 . The optical scanning device according to claim 1 , wherein the light-blocking member protrudes upward from a lower area of a housing.
7 . The optical scanning device according to claim 6 , wherein the protruding edge section is formed oblique in a traveling direction of the at least one second light beam.
8 . The optical scanning device according to claim 1 , wherein the light-blocking member protrudes downward from an upper area of a housing.
9 . The optical scanning device according to claim 8 , wherein the protruding edge section is formed oblique in a traveling direction of the at least one second light beam.
10 . The optical scanning device according to claim 1 , wherein the light-blocking member has substantially the same length as the scanning area of the at least one second light beam.
11 . The optical scanning device according to claim 1 , wherein the light-blocking member is formed integrally with a housing.
12 . The optical scanning device according to claim 1 , wherein the light-blocking member is substantially arc shaped and centered at a position relative to a rotary shaft of the deflecting unit.
13 . The optical scanning device according to claim 12 , wherein a flow of heated air generated in the periphery of the deflecting unit is prevented from being disturbed by the arc shaped light-blocking member.
14 . The optical scanning device according to claim 1 , wherein the light-blocking member protrudes toward the scanning line of the second light beams but does not substantially extend into the scanning line.
15 . An image forming apparatus comprising:
at least two image forming sections each having an image carrier carrying a toner image;
a transfer unit configured to transfer the toner image formed by the image forming section onto a recording medium;
a fixing unit configured to fix the toner image transferred by the transfer unit on the recording medium; and
an optical scanning device configured to form electrostatic latent images on the image carriers,
wherein the optical scanning device comprises:
a light source configured to emit a plurality of light beams as first light beams,
a deflecting unit configured to deflect and scan the first light beams emitted from the plurality of light sources as second light beams having a scanning line that is substantially arc shaped,
a scanning lens disposed in a light path of at least one of the second light beams deflected and scanned by the deflecting unit, and
a light-blocking member interposed between the deflecting unit and the scanning lens;
wherein the light-blocking member is configured to (i) block reflected light generated from the at least one second light beam when the at least one second light beam enters the scanning lens, (ii) protrude toward the scanning line of the second light beams along at least a scanning area of the second light beams, and (iii) include a protruding edge section closest to the scanning line and curved in an arc shape.
16 . A method of reducing image degradation in an optical scanning device comprising:
interposing a light-blocking member between a deflecting unit and a scanning lens, the deflecting unit configured to deflect and scan first light beams from a light source as second light beams having scanning lines that are substantially arc shaped;
wherein the light-blocking member is configured to (i) block reflected light generated from at least one of the second light beams when the at least one second light beam enters the scanning lens, (ii) protrude toward the scanning line of the second light beams along at least a scanning area of the second light beams, and (iii) include a protruding edge section closest to the scanning line and curved in an arc shape.
17 . The method of claim 16 , wherein the protruding edge section has substantially the same arc shape as the scanning line of the second light beams.
18 . The method of claim 16 , wherein the light-blocking member protrudes upward from a lower area of a housing.
19 . The method of claim 18 , wherein the protruding edge section is formed oblique in a traveling direction of the at least one second light beam.
20 . The method of claim 16 , wherein the light-blocking member protrudes toward the scanning line of the second light beams but does not substantially extend into the scanning line.