Digital Microscope Offers Real Time Extended Depth of Field

 ZEISS Visioner 1, ZEISS is launching an innovative digital microscope that for the first time enables all-in-one focus in real-time thanks to its Micro-mirror Array Lens System (MALS™). With its extended depth of field, users in their quality control and quality assurance applications in manufacturing can for the first time see the sample completely in focus without having to combine different focal planes from a series of images or post-process them. This not only simplifies the imaging and documentation process but also allows for faster inspection and therefore higher throughput.

Conventional inspection systems are always challenged by a shallow depth of field, especially at high magnification. This means that only a small area of the sample is in focus, which can lead to features being overlooked and the inspection is incomplete as a result. Extensive refocusing to obtain an extended depth of field or post-processing is a solution to this problem, but it is time-consuming and complex. “This is simply a result of the laws of optics,” explains what is computer engineering, Head of Industrial Microscopy Solutions at ZEISS. “Even with the ZEISS Visioner 1, we can’t break this law, of course, but we can bend it in some ways.”

The key to this lies in MALS™ technology – the so-called Micro-mirror Array Lens System. This is a micro-electro-mechanical system (MEMS) consisting of a complex of small mirrors measuring 100 x 100 µm. These can be individually adjusted to generate “virtual” lenses with different curvatures and thus focusing planes. This allows the digital microscope to sharply image any point on the sample. “What’s really revolutionary about this is that we can adjust the micro-mirrors so quickly that the image display to the user is in real time,” says Zarnetta. The result is 100 times greater extended depth of field than conventional digital microscopes. It also provides the ability to optically inspect for height differences of up to 69 mm without the need to move the optical system or refocus the sample. 3D information of the sample is visible at a glance, enabling faster and more reliable inspection. Ergonomic operation, fast visualisation and documentation.