Delve into the theory and you'll find you can actually only reliably capture resolution around 0.7x your Nyquist frequency.Ī sensor capturing detail at every pixel can perfectly represent data at up to 1/2 of its sampling frequency, so 4000 vertical pixels can represent 2000 cycles (or 2000 line pairs as we'd tend to think of it). If they're slightly misaligned, you may get two grey pixels instead.

Just to make things more tricky, this assumes your pixels are aligned perfectly with the line. If you think about trying to represent a single pixel-width black line, you need at least two pixels to be sure of representing it properly: one to capture the line and another to capture the not-line. Sampling theory dictates that a system can only perfectly reproduce signals at half the sampling frequency (a limit known as the Nyquist Frequency). There's a limit to how much resolution you can capture with any pixel-based sensor. So how bad are these problems and why don't they stop us using it? Resolution However, it isn't entirely without its drawbacks: It doesn't capture nearly as much color resolution as a camera's pixel count seems to imply, it's especially prone to sampling artifacts and it throws away a lot of light. Most importantly, it does a good job of achieving this color capture while still capturing a good level of spatial resolution. The Bayer Color Filter Array is a genuinely brilliant piece of design: it's a highly effective way of capturing color information from silicon sensors that can't inherently distinguish color. Image: based on original by Colin M.L Burnett It seems so obvious, once someone else has thought of it, but capturing red, green and blue information as an interspersed, mosaic-style array was breakthrough. It's unlikely Kodak's Bryce Bayer had any idea that, 40 years after patenting a ' Color Imaging Array,' his design would underpin nearly all contemporary photography and live in the pockets of countless millions of people around the world.

Siemens star pattern use with ccd