Carl Zeiss increases depth of focus by almost 2,000 per cent
Carl Zeiss increases depth of focus by almost 2,000 per cent
Keywords: Nanotechnology, Imaging
Carl Zeiss is addressing the technological challenges posed by the upsurge in nanotechnology and micro-electro- mechanical systems (MEMS) with the launch of DeepView, a revolutionary imaging technique that extends the depth of focus of conventional light microscopes by a factor of 18.
Capable of processing more than seven images per second, DeepView is ideal for the inspection of MEMS components in both development and production.
A MEMS device is frequently composed of at least seven separate layers with examination of its extended vertical dimensions often complicated by moving parts. DeepView images the full depth of a structure in a single real-time image rather than having to repeatedly adjust the focus, saving a significant amount of time and minimising user fatigue. It also defies conventional thinking with a tilt capability even at high magnifications, again easing workload and/or increasing inspection capacity.
Fast and simple, DeepView overcomes the drawbacks of current high depth of focus inspection methods. Scanning electron microscopy (SEM) gives depth of focus but exposes the MEMS' delicate electrostatic structures to potentially destructive vacuums and high-energy electron beams. Laser scanning confocal microsopy and software- based systems artificially extend the depth of focus by producing a stack of images in the vertical plane but require extensive post processing.
DeepView works by placing a wavefront modulator close to the back focal plane of the objective lens that makes the optical system invariant to focus. The primary intermediate image contains raw optical coded information from structures that are in conventional focus, as well as from structures that are above and below conventional focus. After spatial filtering by dedicated software algorithms, a clear image is created ready for immediate display or archiving.
Carl Zeiss is leading the way with imaging techniques for MEMS devices. These microscopic mechanical devices designed to sense, act, think, and communicate are already employed for airbag sensors, digital displays, optical switches and inkjet printheads, with more opportunities on the horizon.
