Color synchronization method and color laser printer

A color laser printer which forms a color image by forming an electrostatic latent image on a photosensitive body using a laser scanning unit, developing the electrostatic latent image, and transferring the developed image onto a transfer belt, the printer comprising:

• a plurality of light sources, which radiate light;
• a timing belt which rotates the photosensitive body;
• a timing display which is provided on the timing belt, which rotates by a rotation of the timing belt, and on which the light radiated from each of the light sources is incident;
• and
• a plurality of light receiving portions, each of which detects the light reflected or transmitted by the timing display and generates a signal;
• wherein a scanning operation starts in the photosensitive body in response to the signal received by each of the light receiving portions.

A color synchronization method used in a color laser printer which forms a color image by forming an electrostatic latent image on a photosensitive body using a laser scanning unit, developing the electrostatic latent image, and transferring the developed image onto a transfer belt, the method comprising:

• causing at least one timing display to be formed on a timing belt which rotates the photosensitive body;
• causing light radiated from the laser scanning unit to be incident on the timing display;
• detecting the light reflected or transmitted by the timing display using a light receiving portion;
• and
• starting a scanning operation in the photosensitive body which corresponds to the timing display, using a signal detected by the light receiving portion.

A color laser printer which forms a color image by forming an electrostatic latent image on a photosensitive body using light generated from a light source of a laser scanning unit, developing the electrostatic latent image, and transferring the developed image onto a transfer belt, the printer comprising:

• a timing belt which rotates the photosensitive body;
• a timing display which is formed on the timing belt to direct the light generated from the light source of the laser scanning unit;
• and
• a light receiving portion which generates a signal in response to the light directed from the timing display to control the photosensitive body.

A color laser printer which forms a color image by forming an electrostatic latent image on a photosensitive body, developing the electrostatic latent image, and transferring the developed image onto a transfer belt, the printer comprising:

• a timing belt which rotates the photosensitive body;
• a timing display which formed on the timing belt;
• and
• a single laser scanning unit radiating light used for both forming the electrostatic latent image on the photosensitive body and detecting the timing display to control the photosensitive body.

A color synchronization method used in a color laser printer which forms a color image by forming an electrostatic latent image on a photosensitive body using a laser scanning unit, developing the electrostatic latent image, and transferring the developed image onto a transfer belt, the method comprising:

• rotating a timing belt which rotates the photosensitive body;
• causing a timing display to be formed on the timing belt;
• directing the light generated from the light source of the laser scanning unit;
• and
• generates a signal in response to the light directed from the timing display to control one of the laser scanning unit and the photosensitive body.