Canon eos5d manual Low-Pass Filter Construction, Microlens Comparison Conceptual Diagram

Advanced Sensor Designs

IV. PERFORMANCE AND RELIABILITY 21

EOS 5D Mark II’s new 21.1-megapixel full-frame CMOS sensor: The advanced single-plate

CMOS sensor in the EOS 5D Mark II achieves the highest performance of any sensor in the

Canon DSLR lineup. It shares many traits with the CMOS sensor found in the flagship

	EOS-1Ds Mark III, including its 36mm x 24mm (35mm format) size,
EOS 5D Mark II Full-Frame CMOS Sensor
	approximately 21.1 effective megapixels with 6.4µm pixel pitch, a 4-channel
(Actual Size)
	data readout, and low-pass filter design. However, this second-generation
	sensor offers increased sensitivity and improved noise reduction circuitry that
	enables standard ISO’s ranging from 100 to 6400 and expanded ISO ranges
24mm	from 50 to 25,600.
		Low-Pass Filter Construction
	The EOS 5D Mark II’s sensor is			Dichroic mirror (Reflects infrared rays)
	designed and manufactured entirely by				Infrared-absorbing glass
36mm	Canon using its state-of-the-art
* Package dimensions: 52.5 mm x 36.5 mm	CMOS semiconductor fabrication and
	microlens-forming process. It includes a					CMOS
protective, double low-pass filter design that separates						sensor
the subject image into horizontal and vertical directions,
a phase plate, and an infrared-absorption glass. (The
front side of the first low pass filter also includes a fluorine
					Low-pass filter -2
coating to help reduce dust adhesion and a dichroic					(Separates image in
					vertical direction)
				Phaser layer
mirror vapor deposition on the rear surface to reflect				(Converts linear polarized light
				into circular polarized light)
infrared rays.)			Low-pass filter -1
			(Separates image in horizontal direction)

Compared to the original EOS 5D, the gap between the on-chip microlenses on the EOS 5D Mark II has been narrowed while the photodiode area ratio (photodiode area divided by the pixel size) has been increased. The distance between the microlens and photodiode has been further reduced to improve light gathering efficiency, and new color filter materials have been added to increase light transmission while retaining accurate color reproduction. These optical

Microlens Comparison (Conceptual Diagram)

Gap between microlenses

Pixel size		Photo diode area	Pixel pitch	Photo diode
	EOS 5D Mark II (6.4 x 6.4 mm)		EOS 5D (8.2 x 8.2 mm)