title: A Simple low-cost device enables four epi-illumination techniques on standard light microscopes.
abstract: Back-scattering darkfield (BSDF), epi-fluorescence (EF), interference reflection contrast (IRC), and darkfield surface reflection (DFSR) are advanced but expensive light microscopy techniques with limited availability. Here we show a simple optical design that combines these four techniques in a simple low-cost miniature epi-illuminator, which inserts into the differential interference-contrast (DIC) slider bay of a commercial microscope, without further additions required. We demonstrate with this device: 1) BSDF-based detection of Malarial parasites inside unstained human erythrocytes; 2) EF imaging with and without dichroic components, including detection of DAPI-stained Leishmania parasite without using excitation or emission filters; 3) RIC of black lipid membranes and other thin films, and 4) DFSR of patterned opaque and transparent surfaces. We believe that our design can expand the functionality of commercial bright field microscopes, provide easy field detection of parasites and be of interest to many users of light microscopy.
authors: Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK.
authors: Robert R
authors: RR
authors: Ishmukhametov
authors: Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK.
authors: Aidan N
authors: AN
authors: Russell
authors: The Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE, UK.
authors: Richard J
authors: RJ
authors: Wheeler
authors: Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK.
authors: Ashley L
authors: AL
authors: Nord
authors: Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK.
authors: Richard M
authors: RM
authors: Berry
mesh_terms: D003365:Costs and Cost Analysis; D008029:Lighting / Q000191:economics / Q000379:methods*; D008853:Microscopy / Q000191:economics / Q000379:methods*; D055096:Optical Devices