| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical device capable of reliably preventing an optical element, such as an fθ lens, from being reversely attached, and to provide an image formation apparatus including the same. <P>SOLUTION: An optical device 6 includes: a laser light source 25; an optical member 30 that has an aspherical lens 301 having an incidence surface 307 on which a laser beam is incident and an emission surface 308 from which a laser beam is emitted, and scans a predetermined target with the laser beam emitted from the emission surface 308; and a housing 33 for housing the optical member 30. The optical member 30 further has first positioning parts 311, 312 on the incidence surface 307 side and second positioning parts 313, 314 on the emission surface 308 side. The housing 33 has a first engaging part 334 to be engaged with the first positioning part 312 and a second engaging part 335 to be engaged with the second positioning part 314. The first positioning parts 311, 312 and the second positioning parts 313, 314 have shapes different from each other. <P>COPYRIGHT: (C)2012,JPO&INPIT |
