Image Stabilization / Resolution Enhancement With Fast Piezo Scanners

Increasing the Resolution of Optical Sensor Chips: Applications of Pixel Sub-Stepping

Optical Resolution in Imaging

Low light conditions create difficult conditions for imaging applications from astronomy to microscopy. Low light intensity means neither the resolution of the chip nor the exposure time for changing or moving objects can be freely chosen. Typical applications are fluorescence microscopy, white-light interferometry (OCT in medical technology or general surface structural analysis), or surveillance cameras and cameras for aerial photography. Further fields of application are scanners used to digitize analog data, e.g. technical drawings, art, paintings, etc. Pixel sub-stepping makes it possible to significantly improve the resolution with relatively little effort.

Restrictions of High-Resolution Chips

The resolution of digital recording methods is determined by the number of imaging pixels of a CCD or CMOS chip, for example. If one wishes to increase the resolution, the number of imaging pixels must be increased.

There are basically two ways of doing this, both of which are relatively expensive and require a lot of effort: either one increases the size of the recording chip or one decreases the size of the pixel. The first case requires a larger recording device and also different imaging optics. In the second case, the light sensitivity decreases with the pixel size. This reduces the separation between image signal and noise signal which, in the end, may even decrease the image quality in spite of the higher resolution.