Vision sensors
Introduction
The image sensor is the element of an electronic camera, both video and still photography, that detects and captures the information that makes up the image. This is achieved by converting the attenuation of light waves (when they pass through or are reflected by bodies) into electrical signals. The waves captured by the sensor can be light or another type of electromagnetic radiation. It is a chip made up of millions of light-sensitive components (photodiodes or phototransistors) that, when exposed, capture the waves projected from an objective "Lens (photography)"), which composes the image. Image sensors are used in various devices, such as digital cameras, medical equipment, and night vision equipment.
Application
The sensor is an array of photosensitive elements that works by converting the light it captures into electrical signals, which can then be converted, analyzed, stored and subsequently represented as a pattern, either analog (such as a sweep or scan signal) or digital (with the consequent sampling and numerical conversion of the luminosity values.
Finally, the computer "File (computing)") file that stores that pattern can be represented on a screen (or printed on photographic paper by performing certain processes) so that our eyes perceive it as an image; A continuous succession of images passing across the screen at high speed is perceived by the eye as a video.
Components
Each of the photosensitive elements of the sensor is called pixel or pixel, a word that comes from the English acronym picture element. The number of pixels on the sensor is usually measured in millions of pixels (or megapixels, Mpx). In general, it can be said that higher numbers indicate the possibility of printing (or viewing) photos at larger sizes with lower quality losses (higher image resolution).
Another important factor regarding the sensor is its size and shape. A large sensor containing a relatively small number of pixels should have a large area per pixel; and vice versa: a small sensor with the same number of pixels will have a small area per pixel. Larger pixel sizes tend to result in better image quality and higher sensitivity.