Large-field objective lens for multi-wavelength microscopy at mesoscale and submicron resolution

Conventional microscopes designed for submicron resolution in biological research are hindered by a limited field of view, typically around 1 mm. This restriction poses a challenge when attempting to simultaneously analyze various parts of a sample, such as different brain areas. In addition, conventional objective lenses struggle to perform consistently across the required range of wavelengths for brain imaging in vivo. Here we present a novel mesoscopic objective lens with an impressive field of view of 8 mm, a numerical aperture of 0.5, and a working wavelength range from 400 to 1000 nm. We achieved a resolution of 0.74 μm in fluorescent beads imaging. The versatility of this lens was further demonstrated through high-quality images of mouse brain and kidney sections in a wide-field imaging system, a confocal laser scanning system, and a two-photon imaging system. This mesoscopic objective lens holds immense promise for advancing multi-wavelength imaging of large fields of view at high resolution.