Abstract: An apparatus to generate a laser beam detect signal includes a reflective mirror arranged on a part of an optical path of a laser beam which forms an electrostatic latent image on a photosensitive body, a beam detect lens to focus the laser beam reflected from the reflective mirror, and a printed circuit board having a photo diode sensor to detect the laser beam passed through the beam detect lens, generating the laser beam detect signal to synchronize a starting point of an image formation of the electrostatic latent image. The apparatus to generate a laser beam detect signal also includes a fixing part to secure the beam detect lens on the printed circuit board so that a center of an optical axis of the beam detect lens is aligned with a detection area of the photo diode sensor. Alternatively, the beam detect lens and the photo diode sensor may be integrally formed with each other. As a result, deterioration of printing quality due to errors from part allowance and an assembling process is prevented.

Abstract: An apparatus to detect a synchronizing signal includes a reflective mirror arranged on a part of an optical path of a laser beam which forms an electrostatic latent image on a photosensitive body, a beam detect lens to converge or disperse the laser beam reflected from the reflective mirror, and a printed circuit board having a photo diode sensor to detect the laser beam passed through the beam detect lens, generating a synchronizing signal to synchronize a starting point of an image formation of the electrostatic latent image. The apparatus to detect the synchronizing signal also includes a fixing part to secure the beam detect lens on the printed circuit board so that a center of an optical axis of the beam detect lens is aligned with a detection area of the photo diode sensor. Alternatively, the beam detect lens and the photo diode sensor may be integrally formed with each other. As a result, deterioration of printing quality due to errors from part allowance and an assembling process is prevented.