Optical microscopy involves the diffraction, reflection, or refraction of electromagnetic radiation/electron beams interacting with the specimen, and the collection of the scattered radiation or another signal in order to create an image. This process may be carried out by wide-field irradiation of the sample (e.g. standard light microscopy and transmission electron microscopy) or by scanning a fine beam over the sample (e.g. confocal laser scanning microscopy and scanning electron microscopy). Scanning Probe Microscopy involves the interaction of a scanning probe with the surface of the object of interest. The development of microscopy revolutionised biology, gave rise to the field of histology and so remains an essential technique in the life and physical sciences. Micro-photoluminescence or Micro-PL spectroscopy is a powerful tool for investigating the optical and electronic properties of single nanostructures. Oxford Instruments' optical cryostats are used to study Microscopy/Micro-PL - the type of cryostat will depend on your requirements in terms of sample environment (vacuum or exchange gas) and cooling technology (nitrogen, helium or Cryofree).