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Programmable illumination control is essential for many computational microscopy techniques. Conventional light source array is often arranged on a fixed grid of a planar surface for providing programmable sample illumination. Here, we report the development of a freeform illuminator that can be arranged at arbitrary 2-dimensional or 3-dimensional (3D) surface structures for computational microscopy. The freeform illuminator can be designed in a small form factor with a dense light source arrangement in 3D. It can be placed closer to the sample for providing angle-varied illumination with higher optical flux and smaller angular increment. With the freeform illuminators, we develop a calibration process using a low-cost Raspberry-Pi image sensor coated with a monolayer of blood cells. By tracking the positional shift of the blood-cell diffraction patterns at 2 distinct regions of the coded sensor, we can infer the 3D positions of the light source elements in a way similar to the stereo vision reconstruction approach. To demonstrate the applications for computational microscopy, we validate the freeform illuminators for Fourier ptychographic microscopy, 3D tomographic imaging, and on-chip microscopy. We also present a longitudinal study by tracking the growth of live bacterial cultures over a large field of view. The reported freeform illuminators and the related calibration process offer flexibilities and extended scope for imaging innovations in computational microscopy.
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A FLEXIBLE ORIGAMI OPTO-ELECTRO ARRAY FOR IN VIVO OPTOGENETIC STIMULATION AND ELECTROPHYSIOLOGY RECORDINGS FROM DORSAL ROOT GANGLION
In this study, a thin-film, three-dimensional (3D) opto-electro array with 4 addressable microscale light-emitting diodes for surface illumination of dorsal root ganglions (DRGs) and 9 penetrating electrodes for simultaneous recordings of light-evoked DRG activities is described for Developing a tool to better understand the relationship between spindle length-sensitive afferents from hip muscles and both interlimb coordination and gait selection. Importantly, using the origami design concept, the array can be fabricated directly on a silicon wafer in a two-dimensional (2D) configuration, which can transform into a 3D structure by folding.
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- Award ID(s):
- 2024270
- PAR ID:
- 10342292
- Date Published:
- Journal Name:
- Hilton Head 2022: 2022 Solid-State Sensors, Actuators, and Microsystems Workshop
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- The DOI is not currently available.
