Piezo specialist PI
has published a paper on image resolution enhancement and image stabilization
for electronic imaging sensors based on fast piezo actuation.
The paper describes basic techniques and explains different piezoelectric motion
principles such as flexure mechanisms and ultrasonic motors.
Paper Download at: http://www.pi-usa.us/pdf/
Resolution Limiting Factors
In order to increase the resolution of common imaging detectors such as CCDs
or CMOS either the chip size can be increased or the pixel size be reduced;
both solutions have undesirable side-effects.
The first case requires a larger recording device and different imaging optics.
In the second case, light sensitivity decreases with the pixel size, also reducing
the signal/noise ratio.
Super-Resolution with Pixel Sub-Stepping
With so-called pixel sub-stepping, the recording area is moved on predefined
paths with a defined frequency. This “dithering”, where the travel
is less than the size of a pixel, causes the pixel to be exposed several times
on the recording area, producing a virtual “pixel multiplier” which
can significantly improve the resolution without negative side-effects.
Today, small and cost efficient piezo devices (in-plane scanners or tip/tilt
mechanisms) are available to handle the task. In addition to image resolution
enhancement, these devices are also fast enough to remove jitter induced by
vibration from images and video.
PI is a leading manufacturer of piezo actuators, piezo linear motors and precision
motion-control equipment for optics, photonics, bio-nanotechnology & semiconductor
applications. PI has been developing and manufacturing standard & custom
precision products with piezoceramic and electromagnetic drives for 35+ years.
The company has been ISO 9001 certified since 1994 and provides innovative,
high-quality solutions for OEM and research. PI is present worldwide with eight
subsidiaries and total staff of 500+