Optical deflection device, image printing apparatus, and optical deflection device manufacturing method

An optical deflection device manufacturing method comprising the steps of:

• integrally fitting a flange member on a bearing;
• performing flat work for a holding surface of the flange member arranged to hold a polygon mirror having a plurality of reflecting surfaces so as to become a surface perpendicular to an axis of rotation of the bearing;
• performing surface roughening for the holding surface of the flange member;
• applying an adhesive between the holding surface of the flange member and a held surface of the polygon mirror held by the holding surface;
• and
• mounting a press member which presses and biases the polygon mirror against the flange member, wherein a surface roughness (Ry) of the holding surface having undergone surface roughening satisfies a conditional expression:
• 3 μm≦Ry≦20μm
• where Ry:
• maximum height (JIS B0601), and
• wherein the adhesive has a Young's modulus of not more than 1700 MPa at 25° C.

An optical deflection device manufacturing method comprising the steps of:

• integrally fitting a flange member on a bearing;
• performing flat work for a holding surface of the flange member arranged to hold a polygon mirror on a held surface of the polygon mirror, the polygon mirror having a plurality of reflecting surfaces so as to become a surface perpendicular to an axis of rotation of the bearing;
• performing surface roughening for the held surface of the polygon mirror;
• applying an adhesive between the holding surface of the flange member and the held surface of the polygon mirror held by the holding surface;
• and
• mounting a press member which presses and biases the polygon mirror against the flange member, wherein a surface roughness (Ry) of the held surface having undergone surface roughening satisfies a conditional expression:
• 3 μm≦Ry≦20 μm
• where Ry:
• maximum height (JIS B0601), and
• wherein the adhesive has a Young's modulus of not more than 1700 MPa at 25° C.