Optical device, scanning optical device, and image forming device

An optical device comprising:

• an optical element having a first surface and a second surface;
• a first seat surface member that abuts on the first surface of the optical element;
• a first pressing member that abuts on the second surface of the optical element at a position facing the first seat surface member via the optical element, and applies a pressing force to the abutment position to press the optical element against the first seat surface member;
• an adjustment member that abuts on the second surface of the optical element at a position different from the first pressing member, and displaces the abutment position to adjust a posture of the optical element;
• a second pressing member that abuts on the first surface of the optical element at a position facing the adjustment member via the optical element and applies a pressing force to the abutment position to press the optical element against the adjustment member;
• and
• a fall prevention part that prevents the optical element from falling off the first seat surface member or the adjustment member by regulating displacement of the optical element in an in-plane direction,
• wherein
• the fall prevention part is disposed in a non-pressed state with the optical element.

An optical device comprising:

• an optical element having a first surface and a second surface;
• a first seat surface member that abuts on the first surface of the optical element;
• a first pressing member that abuts on the second surface of the optical element at a position facing the first seat surface member via the optical element, and applies a pressing force to the abutment position to press the optical element against the first seat surface member;
• an adjustment member that abuts on the second surface of the optical element at a position different from the first pressing member, and displaces the abutment position to adjust a posture of the optical element;
• and
• a second pressing member that abuts on the first surface of the optical element at a position facing the adjustment member via the optical element and applies a pressing force to the abutment position to press the optical element against the adjustment member,
• wherein
• at least one of the first seat surface member, the first pressing member, the adjustment member, and the second pressing member has a spherical shape at a portion that abuts on the optical element.