Team:TU Darmstadt/tech/hardware
ChiTUcare
Digital Inline Holographic Microscopy - An iGEM Approach
In light of the iGEM competition, the need for analyzing the 3D structures of hydrogel and E.Coli at micrometer scales has arisen. Our project aims at constructing a low cost Digital Inline Holography Microscope (DIHM). The DIHM features on its ease-of-use, lens-less inline structure, and the state-of-art reconstruction algorithms from holograms to 3D visualization with micrometer resolution. The working principle of a DIHM starts with a point laser source, emanating a spherical wave through a pinhole, illuminating the object to be observed, and forming a magnified diffraction pattern at the CCD camera, followed by reconstruction algorithms. The holograms collected by the CCD camera already contains the difference of intensity and phase shifts, compared with the reference beam from the spherical wave, thus the inline structure without the need of a lens or beam splitter. Our project uses easily accessible hardware components: an xbox 360 pickup as the laser source, DIYouware PCB board for the alignment and laser intensity control, a 1 µm pinhole, a Pi-cam and the Raspberry Pi for taking pictures, and certain 3D printed parts to assemble the microscope. The open source library Holopy is then deployed to reconstruct the 3D volumes from the holograms.
