LIGHT SCANNING UNIT

A light scanning device is provided to prevent thermal deformation of a frame by disposing a buffer member for relieving thermal stress between the frame and a support unit. A light scanning device installed at a support unit(75) of an image forming device to scan the light on an exposed surface of a photoconductor is composed of a light source(50) for generating and irradiating the light; an optical deflector(60) for deflecting the light incident from the light source and then irradiating the deflected light; a frame(70) installed at the support unit and provided with a flange part(72) having a combining groove(74), wherein the light source and the optical deflector are placed in the frame; a buffer member(77) fitted to the combining groove, wherein a portion of the buffer member is interposed between the flange part and the support unit to relieve thermal stress; and a combining member(73) joined to the support unit through the combining groove to join the frame to the support unit.