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参数：

Resolution: more than 640x480
Takes pictures every 3 minutes and stores them in flash memory
USB port to download the pictures to computer.
Batteries: 2x AA cells
Size: ~ 2 square inches

像素大于640x480
每3分钟自动照相并存储为FLASH格式
USB接口下载图片到电脑
电池：2xAA
尺寸：2英寸
All it needs to do is take a picture every couple of minutes and store the picture to flash memory. Download is by usb to a PC. It should operate from 2 x 1.5 AA batteries for as long as possible (2-3 days) therefore it probably will need to be cmos. It will be used for time lapse photography. The quality should be better than 640x320n preferably 2megapixel. It is a fixed focal length but I prefer using lenses rather than a pin hole.
It has to run from batteries. The camera can go to “sleep” or shutdown between pictures to conserve power
No flash
No LCD (only a USB port)
No software (perhaps a USB driver if required)