A Simple low-cost device enables four epi-illumination techniques on standard light microscopes

Area of Science:

• Optical microscopy
• Biomedical imaging
• Materials science

Background:

• Advanced microscopy techniques like BSDF, EF, IRC, and DFSR are costly and have limited availability.
• Commercial microscopes often lack the versatility for diverse imaging needs.

Purpose of the Study:

• To develop a simple, low-cost miniature epi-illuminator combining four advanced microscopy techniques.
• To enhance the functionality of standard commercial bright-field microscopes.

Main Methods:

• Designed a miniature epi-illuminator that fits into the DIC slider bay of a commercial microscope.
• Integrated back-scattering darkfield (BSDF), epi-fluorescence (EF), interference reflection contrast (IRC), and darkfield surface reflection (DFSR) into one device.
• Demonstrated functionality without requiring additional microscope components.

Main Results:

• Successfully detected malaria parasites in unstained erythrocytes using BSDF.
• Performed EF imaging, including filter-free detection of DAPI-stained Leishmania.
• Achieved IRC imaging of black lipid membranes and DFSR of patterned surfaces.

Conclusions:

• The developed epi-illuminator significantly expands the capabilities of commercial bright-field microscopes.
• The low-cost design facilitates advanced imaging techniques, including field detection of parasites.
• This versatile tool is expected to benefit a wide range of light microscopy users.