[scan device and a method for enhacing the life of the same]

A scan device, suitable for scanning a document, comprising:

• a plurality of light source modules, wherein each of the plurality of light source modules comprises a lamp holder and a lamp, the plurality of lamps are disposed inside the plurality of lamp holders respectively, and each of the lamps can provide a light with a predetermined brightness to the document;
• a random selecting device, electrically coupled to the scan chassis, and used to randomly select and turn on one of the plurality of lamps in the scan chassis;
• a brightness judging device, electrically coupled to the scan chassis;
• and
• a chart, disposed above the scan chassis.

A method for enhancing a life of a scan device, comprising:

• (a) providing a scan chassis, wherein the scan chassis comprises a plurality of lamps, a reflection mirror set, an optical lens set, and an image capturing device, and each of the lamps can provide a light with a predetermined brightness to a document;
• and
• (b) randomly selecting and turning on one of the lamps
• (c) scanning a chart so as to obtain a scanning result;
• and
• (d) determining whether the brightness of the scanning result is higher than a predetermined value or not, if it is, starting the scanning, and if the brightness of the scanning result is lower than the predetermined value, selecting and turning on another of the lamps.