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Many people consider the quality and sensitivity of CCD image sensors to be superior to those of CMOS image sensors, and since both of these factors have a large impact on an image's expression, CCD image sensors are often used in professional-level equipment. CMOS image sensors, on the other hand, have the advantages of high-speed signal readout and low power consumption. Also, since CMOS image sensors and their peripheral circuits can be designed to fit onto a single chip, they are used primarily for small-sized, low-cost products, e.g., mobile phones and toy cameras.

	CCD	CMOS
Sensitivity	*
Image quality	*
Compact, single-chip design		*
High-speed readout		*

Normally, two types of transistors are used: P-type and N-type. These two types are combined into one semiconductor, called a CMOS (Complementary Metal-Oxide Semiconductor). Mounting both P-channel MOS-FET and N-channel MOS-FET on the same semiconductor substrate reduces power consumption and speeds up operation.

CCD		CMOS

CCD image sensors apply a voltage to each electrode, then use a relay system to transfer the charge and amplify the signal.		In a CMOS image sensor, each pixel consists of a photodiode and a switch that employs a CMOS transistor. The signal from each pixel is amplified. Another switch is mounted to each of the photodiodes, which are arranged in a lattice pattern, and the successive operation of these switches allows each pixel to be directly read and its data to be transferred at high speed.