Imaging in biotechnology : Standard measurement for digital microscopes

Abstract

The image quality determining and comparison of digital microscopes is important so that repeatable results can be achieved. The focus is mainly on digital brightfield microscopes. The measurement of image quality benefits customers and it is especially important when automatic diagnostics are developed and utilized. Image quality depends on the sensor, lens, image processing and display on which the image is viewed. The factors affecting image quality are presented. The following features are the most important and thus introduced more deeply: resolution, colors, dynamic range, image stitching quality, and performance of software. It is presented how they can be measured objectively with existing methods and equipment and how current standards guide the image quality measurements. In this thesis resolution, color, and dynamic range slide were designed. Small software for estimate stitching accuracy was created and tested with artificial images. Overall it can be said that proper image quality standards for brigtfield microscopes are not available. On the market there are not enough methods and equipment for image quality measurement of microscopes. This is caused by small market size, great technical variation between different microscopes, and production problems of consistent quality microscopic image quality slides.