Pixel pitch
With pixel pitch (of English. Pixel pitch ) is the direct distance of the pixels in image sensors or monitors (there also Dot Pitch called) denotes measured from the pixel center to the pixel center.
Image sensors
The smaller the distance between the individual photodiodes on an image sensor, the higher the possible image resolution for a given size of the sensor, but the lower the amount of light quanta that fall on the individual diode.
A higher number of megapixels with the same sensor size is bought at the price of a lower amount of light per pixel, which increases the effort of the camera-internal signal amplification and image processing. With digital cameras, for example, the image quality is often improved through increasingly sophisticated signal processing. This is partly done through the massive use of soft focus and contour enhancers, which reduce the noise, but can worsen the resolution by reducing the image information.
The smaller the pixel pitch, the lower the value of the useful aperture , i.e. the f-number below which the resolution decreases due to diffraction effects . Shrinks with the pixel pitch of the aperture range in which the one hand aberrations by stopping down even be reduced, on the other hand, no diffraction blur occurs.
With a f-number of 2.0 and a light wavelength of 550 nanometers (maximum sensitivity of the human eye in the green), the diameter of the diffraction disk for an image of an infinitely distant, focused point is, for example, 2.7 micrometers and at a f-number of 16.0 already 21 microns. With 6000 pixels in the image width, image sensors with a width of around 16 millimeters and 126 millimeters respectively would have to be used under these two conditions. Even when using highly corrected objectives with a very high optical resolution, it does not make sense to use image sensors that have a smaller spacing between the image points on the sensor than the size of the corresponding diffraction disk.
