Reducing pixel size to increase pixel density leads to poorer sensitivity and a narrower dynamic range. Canon has realized both high resolution and enhanced sensitivity despite pixel-size reduction by closing the gaps between its microlenses. Furthermore, Canon gave these smaller pixels a higher light storing capacity by boosting the circuit density inside each. This has expanded the signal output range in low ISOs. Thanks to this expanded range and high sensitivity, EOS DIGITAL cameras have a wider selection of ISO settings. With a convex shape to best capture light, microlenses are lined up on the CMOS sensor surface with each lens matched to a single pixel. By shrinking the gap between these minute convex lenses, which allows for ample individual lenses, Canon has dramatically enhanced the sensor’s light-gathering efficiency despite an increased pixel density. This enhancement results in the expansion of the signal output range in high ISOs. In order to boost light condensing efficiency, Canon used its technological ingenuity to reduce the thickness of the membrane that covers the surface of the sensor. Doing so minimizes interference to the light as it passes through the membrane—which acts as a light-shielding layer—on its way to the photodiodes. This maximizes the light intake to the photodiodes. This technological feat enables the EOS-1Ds Mark III to have an exposure value of ISO 1600 as its normal setting, despite the fact that the size of a single pixel is as small as 6.4µm square. Page top