Cell-Phone-Based Platform for Biomedical Device Development and Education Applications

TLDR

The authors develop two phone attachments that convert a commercial smartphone into a 350× microscope and a visible‑light spectrometer, aiming to provide affordable diagnostic and educational tools. The microscope achieves 1.5‑µm resolution over a 150×150 µm field (350×350 µm after processing) and the spectrometer offers a 300‑nm bandwidth with ~5‑nm resolution, both built by repurposing the phone’s lens and image sensor. The devices enable high‑quality imaging of stained and unstained blood smears comparable to commercial microscopes for clinical diagnosis, and the spectrometer can acquire tissue transmission and fluorescence spectra, demonstrating medical applicability.

Abstract

In this paper we report the development of two attachments to a commercial cell phone that transform the phone's integrated lens and image sensor into a 350× microscope and visible-light spectrometer. The microscope is capable of transmission and polarized microscopy modes and is shown to have 1.5 micron resolution and a usable field-of-view of 150×150 with no image processing, and approximately 350×350 when post-processing is applied. The spectrometer has a 300 nm bandwidth with a limiting spectral resolution of close to 5 nm. We show applications of the devices to medically relevant problems. In the case of the microscope, we image both stained and unstained blood-smears showing the ability to acquire images of similar quality to commercial microscope platforms, thus allowing diagnosis of clinical pathologies. With the spectrometer we demonstrate acquisition of a white-light transmission spectrum through diffuse tissue as well as the acquisition of a fluorescence spectrum. We also envision the devices to have immediate relevance in the educational field.