Microscanning
Encyclopedia
Microscanning is a method for increasing resolution of digital camera
s. With the color co-site sampling
identically colored pixels in several frames of the specimen, obtained by moving the sensor with a piezo
mechanism in a regular raster
, are combined to a sharp resulting image. The detector, however, can be also translated by a fraction of the pixel pitch: this way also the interstitial space between sensor pixels gets scanned and the number of pixels in the final image is increased. Three positions on the x and y axes increase the image size by a factor of 9, for instance from the common 1388 x 1040 pixels to 4164 x 3120 pixels (see Sony ICX285 series). The color co-site sampling
used at the same time ensures correct reproduction of colors at the pixel density produced.
Whether the spatial resolution will increase accordingly, depends on the optical resolution
of the complete system. The relevant parameter is the resolving power, i.e. how many lines per mm can be resolved. It increases with the aperture of the optical system and is inversely proportional to its magnification. As a result a low-resolution camera with 500 lines would be enough for an 100X objective with 0.9 aperture. On the other hand low-magnification objectives profit most from micro scanning: for instance for a 2,5X objective with N.A.=0.12 cameras with as high as 2500 lines resolution could be used.
Digital camera
A digital camera is a camera that takes video or still photographs, or both, digitally by recording images via an electronic image sensor. It is the main device used in the field of digital photography...
s. With the color co-site sampling
Color co-site sampling
Color co-site sampling is a system of photographic color sensing, wherein 4, 16 or 36 images are collected from the sensor and merged to form a single image. Each subsequent image physically moves the sensor by exactly one pixel, in order to collect R, G and B data for each pixel, known as...
identically colored pixels in several frames of the specimen, obtained by moving the sensor with a piezo
Piezoelectric motor
A piezoelectric motor or piezo motor is a type of electric motor based upon the change in shape of a piezoelectric material when an electric field is applied. Piezoelectric motors make use of the converse piezoelectric effect whereby the material produces acoustic or ultrasonic vibrations in order...
mechanism in a regular raster
Raster scan
A raster scan, or raster scanning, is the rectangular pattern of image capture and reconstruction in television. By analogy, the term is used for raster graphics, the pattern of image storage and transmission used in most computer bitmap image systems...
, are combined to a sharp resulting image. The detector, however, can be also translated by a fraction of the pixel pitch: this way also the interstitial space between sensor pixels gets scanned and the number of pixels in the final image is increased. Three positions on the x and y axes increase the image size by a factor of 9, for instance from the common 1388 x 1040 pixels to 4164 x 3120 pixels (see Sony ICX285 series). The color co-site sampling
Color co-site sampling
Color co-site sampling is a system of photographic color sensing, wherein 4, 16 or 36 images are collected from the sensor and merged to form a single image. Each subsequent image physically moves the sensor by exactly one pixel, in order to collect R, G and B data for each pixel, known as...
used at the same time ensures correct reproduction of colors at the pixel density produced.
Whether the spatial resolution will increase accordingly, depends on the optical resolution
Optical resolution
Optical resolution describes the ability of an imaging system to resolve detail in the object that is being imaged.An imaging system may have many individual components including a lens and recording and display components...
of the complete system. The relevant parameter is the resolving power, i.e. how many lines per mm can be resolved. It increases with the aperture of the optical system and is inversely proportional to its magnification. As a result a low-resolution camera with 500 lines would be enough for an 100X objective with 0.9 aperture. On the other hand low-magnification objectives profit most from micro scanning: for instance for a 2,5X objective with N.A.=0.12 cameras with as high as 2500 lines resolution could be used.