Multiple beam laser scanner using lasers with different aperture sizes

An image forming apparatus, comprising:

• an image bearing member for forming an image thereon, said image bearing member having photoresponse characteristics;
• an array of vertical cavity surface emitting lasers for producing light beams, each of the lasers producing a light beam, the lasers being manufactured to have a plurality of different aperture sizes, the plurality of aperture sizes including a first aperture size and a second aperture size, the first aperture size being larger than the second aperture size;
• and
• a scanning system disposed to utilize the light beams from said array of vertical cavity surface emitting lasers to produce a plurality of scan lines on the surface of said image bearing member,
• wherein the lasers with the first aperture size produce spots on said image bearing member which in turn produce dots of a first size on a printing medium, and the lasers with the second aperture size produce spots on said image bearing member which in turn produce dots of a second size on the printing medium, the first size being larger then the second size.

A method for printing dots of a controlled size on a printing medium using a laser-based image forming apparatus having an image bearing member and an array of lasers, the lasers of the array of lasers being manufactured to have a plurality of different aperture sizes, said method comprising:

• (a) receiving image information indicating an image to be printed onto the printing medium;
• (b) selecting a set of the lasers for printing from the lasers of the array of lasers based on the aperture size;
• (c) scanning the set of the lasers in accordance with the image information so as to scan the image onto the image bearing member;
• and
• (d) transferring the image from the image bearing member to the printing medium.

A method for printing dots of a controlled size on a printing medium using a laser-based image forming apparatus having an image bearing member and an array of lasers, the lasers of the array of lasers being manufactured to have a plurality of different aperture sizes, light beams from the lasers produce a plurality of scan lines over the surface of the image bearing member, and the lasers of the array of lasers are arranged in columns perpendicular to a scan direction over the lasers, and within each column there is at least one laser having a first aperture size and at least one aperture having a second aperture size, the first aperture size being larger than the second aperture size, said method comprising:

• (a) receiving image information indicating an image to be printed onto the printing medium;
• (b) for each scan line, determining whether one or more of the lasers associated with a particular scan line should be driven based on dot size requested by the image information;
• (c) for each scan line, driving the lasers determined in (b) so as to scan the image onto the image bearing member;
• and
• (d) transferring the image from the image bearing member to the printing medium.