Scanning method for performing a low resolution scan by using a high resolution scanning module

A high resolution scanning module capable of performing a low resolution scan, the scanning module comprising:

• a plurality of linearly arranged photo sensors, each of the photo sensors being capable of sensing light transmitted from a document to generate correspondent induced charges;
• a shift register comprising a plurality of serially connected storage units and an output port, the number of the storage units being equal to the number of the photo sensors, each of the storage units being electrically connected with a correspondent photo sensor for storing the induced charges generated by the connected photo sensor, the induced charges stored in the storage units being able to serially migrate toward the output port and sequentially output from the output port;
• and,
• an output unit electrically connected to the output port of the shift register for receiving the induced charges output from the output port and generating a correspondent induced voltage, the output unit for outputting the induced voltage of the output unit after induced charges of a first predetermined number of the storage units are accumulated in the output unit, the first predetermined number being approximately equal to the high resolution divided by the low resolution the output unit then resetting to continue receiving the induced charge from the output port;
• wherein the accumulated induced charges from the first predetermined number of the storage units is approximately equal to the accumulated induced charges generated by each of the photo sensors after exposure to the light transmitted from the document when scanning the document in high resolution.

A scanning method for performing a low resolution scan using a high resolution scanning module, the scanning module comprising:

• a plurality of linearly arranged photo sensors, each of the photo sensors being capable of sensing light transmitted from a document to generate correspondent induced charges;
• a shift register comprising a plurality of serially connected storage units and an output port, the number of the storage units being equal to the number of the photo sensors, each of the storage units being electrically connected with a correspondent photo sensor for storing the induced charges generated by the connected photo sensor, the induced charges stored in the storage units being able to serially migrate toward the output port and sequentially output from the output port;
• and
• an output unit electrically connected to the output port of the shift register for receiving the induced charges output from the output port and generating a correspondent induced voltage;
• the low resolution scanning method comprising:
• activating the photo sensors to sense the light transmitted from the document for a first predetermined time period to generate correspondent induced charges;
• transmitting the induced charges from the photo sensors into corresponding storage units;
• shifting the induced charges stored in the storage units into the output unit in sequence;
• outputting the induced voltage of the output unit after induced charges of a first predetermined number of the storage units are accumulated in the output unit, and resetting the output unit to continue receiving the induced charges from the output port, the first predetermined number being approximately equal to the high resolution divided by the low resolution;
• and
• repeating the previous step until all the induced charges in the storage units are output.