We report the use of non-contact optical interferometric microscopy (OIM) for surface topographic profiling. A Linnik optical configuration is used to create interferograms of an object surface. When the coherence condition between the two beams is met the phase information of the object surface can be extracted to establish its topographic contour image. Using a four-image phase-shifted algorithm with the synchronization of a piezoelectric actuator reference mirror positioning, the present single camera OIM can reconstruct a surface topography with a field of view of 312 µm × 234 µm, axial resolution of 3.31 nm, and lateral resolution of 488 nm, and an estimated maximum topography depth of 270 nm.

We report a large field of view FOV low-cost smart fundus camera with non-mydriatic and spectral band illumination features for the purpose of diagnosing central nervous system diseases such as Alzheimer’s disease. By combining a customized optical lens group, ring light emitting diode light source, Li-battery, and Raspberry Pi we can port the spectrally selected light source through a 4 mm diameter pupil. Taking advantage of the open hardware platform and Linux operating system, we integrate two narrowband filters explicitly selected based on the unique spectrums of biomarkers (580 nm and 660 nm) with a Raspberry Pi camera module to obtain high quality images for the purpose of enhancing the visibility of retinal vasculature and nerve fiber layer.