MOOC: Instrumental analysis of cultural heritage objects

2. Optical microscopy

In this course the general introduction to optical microscopy and an overview of the different types of optical microscopes  (stereo microscope, polarized light microscope, fluorescence microscope, etc.) will be given. Based on the type of materials (textile fibres, paint cross-sections, archaeological materials, etc.) practical examples and explanations will be given.

Microscopic analysis

Optical microscopy is often one of the first methods for the analysis of cultural heritage objects. It is a fast method for examing and identifying materials like fibres, paints, minerals, ceramics, metals, etc. This method is non-destructive for the sample, and in some cases, samples removing from the original object is not needed.

Microscopes enable the magnification of small objects or smaller parts of the larger objects and provide visual information of the sample. It is possible to obtain valuable information about the structure, size, shape, colour, thickness, dimensions, and other characteristics of small features of the sample. Also, it allows to observe the surface of the artefacts without removing samples from the object and evaluate its condition (e.g. cracks, broken areas, moulds and dirt on the objects, etc.). 

There are different types of microscopes available. They may differ by size, design, magnification range, resolution, etc. Nowadays, microscopes can be equipped with a CCD camera and are connected to the computer. Specific software allows to observe, take photos and manipulate the images of the sample. This gives more possibilities to examine and store photos of tiny objects. There are also small USB digital microscopes (so-called handheld digital microscopes) available, enabling the primary examination in situ in museums, churches, etc.

In this lecture light microscopy, polarized light microscopy, and fluorescence microscopy are discussed.

This section is divided into three subsections:

 

The slides used in the video can be downloaded from here: