Optical scanner and image forming apparatus including the same

An optical scanner. comprising:

• a scanning optical system that scans a light beam and quides the light beam onto an image carrier:
• a housing including a retaining portion that retains an optical element as a component of the scanning optical system;
• and
• a pressing and retaining member that presses the optical element so as to retain the optical element to the retaining portion,
• the optical scanner exposing to light a surface of the image carrier so as to form thereon an electrostatic latent image with attenuated electrostatic charge,
• wherein
• the pressing and retaining member includes:
• a main body;
• and
• at least one pressing portion that is connected to the main body and presses the optical element retained to the retaining portion toward the retaining portion
• the housing includes:
• a support portion that is formed to be opposed to the retaining portion and supports the main body;
• and
• an engaged portion to be engaged with an engaging portion formed in the main body,
• in a first state where the pressing and retaining member is inserted between the retaining portion and the support portion so that the engaging portion is engaged with the engaged portion, the at least one pressing portion presses the optical element toward the retaining portion,
• while the pressing and retaining member shifts from a second state where the engaging portion is not engaged with the engaged portion to the first state, a distal end of the at least one pressing portion passes beyond a boundary between the retaining portion and the optical element and abuts on a part of the housing,
• the at least one pressing portion includes:
• a pressure contact point that makes a point contact or a linear contact with the optical element in the first state;
• a proximal end that extends in a direction directed to the main body from the pressure contact point;
• and
• an extension that extends in an opposite direction to the main body from the pressure contact point,
• while the pressing and retaining member shifts from the second state to the first state, after the extension has passed beyond the boundary between the retaining portion and the optical element and abutted on the part of the housing, the pressure contact point makes a point contact or a linear contact with the optical element retained to the retaining portion,
• the retaining portion has an L shape as viewed sideways, including:
• a first retaining surface opposed to a side surface of the optical element;
• and
• a second retaining surface opposed to a lower surface of the optical element,
• the pressing and retaining member includes, as the at least one pressing portion:
• a first pressing portion that presses the optical element toward the first retaining surface;
• and
• a second pressing portion that presses the optical element toward the second retaining surface, and
• the pressure contact point, the proximal end, and the extension are formed in the second pressing portion.