HP 3015 Service Manual - Page 111

HP LaserJet 3020 and 3030 all-in-one unique components This section presents an overview of the relationships between unique major components in the HP LaserJet 3020/3030 all-in-one. This section describes the optical scanning system and ADF pickup and feed system used in the HP 3020 and 3030 product. It does not describe the image-formation system that is common to the HP LaserJet 3015, 3020, and 3030 products. For information about image formation, see Image-formation system. Scanner and ADF functions and operation The following sections describe how the document scanner and the automatic document feeder (ADF) function. Scanner functions The scanner uses a light source, a color-separation method, and a charge-coupled device array (CCD) to collect optical information about the document and transform that into an image file. The scanner consists of these elements: ● a lamp (cold-cathode fluorescent bulb) ● five mirrors and a lens ● a CCD Figure 4-14. HP LaserJet 3020 and 3030 optical system The scanner lamp illuminates a small strip of the document (called the raster line). The mirrors direct the light through the lens to the CCD. The CCD senses and records the light, creating an analog representation of the raster line. If the ADF is being used, the document then advances in the ADF to the next raster line. If the flatbed is being used, the scanner module advances to the next raster line. This advancing and collection process continues to the end of the sheet. The image data is collected in the motor controller board, where it is processed and sent to the formatter. The formatter then handles the image data, outputting it as a copy, sending it through the LIU as a fax (in the LJ 3030), or directing it to the computer as scanner output. ENWW HP LaserJet 3020 and 3030 all-in-one unique components 93