| 摘要 |
PROBLEM TO BE SOLVED: To provide an exposure device that inhibits, with a simple configuration, generation of a gradient in the refractive index of a lens by heat generating from a polygon motor, and to provide an image forming apparatus including the exposure device.SOLUTION: An exposure device 123 includes a polygon motor 71 and an f&thetas; lens 85. As the polygon motor 71 is driven to rotate while generating heat, the temperature at a right wall 810 side of the f&thetas; lens 85 is apt to be lower than the temperature at a left wall 812 side of the f&thetas; lens 85. The exposure device 123 includes a recessed part 80D laterally extending above the f&thetas; lens 85. A plate 500 is disposed above the right wall 810 side of the f&thetas; lens 85 to cover the recessed part 80D. The plate 500 inhibits the heat at the right wall 810 side of the f&thetas; lens 85 from radiating upward. |
