What is the difference between CCD and CMOS image sensors in a digital camera?

CMOS sensors are much less expensive to manufacture than CCD sensors, but better imaging quality in medical field.

Both CCD (charge-coupled device) and CMOS (complementary metal-oxide semiconductor) image sensors start at the same point -- they have to convert light into electrons. If you have read the article How Solar Cells Work, you understand one technology that is used to perform the conversion. One simplified way to think about the sensor used in a digital camera (or camcorder) is to think of it as having a 2-D array of thousands or millions of tiny solar cells, each of which transforms the light from one small portion of the image into electrons. Both CCD and CMOS devices perform this task using a variety of technologies.