Tiny Lens-less Endoscope Captures
Researchers developed tiny lensless endoscope, a new self-calibrating endoscope. Not to mention, this endoscope produces 3D images of objects. With smaller than a single cell without a lens or any optical, electrical, or mechanical components. The tip of the endoscope measures just 200 microns across, width of a few human hairs twisted together. This minimally invasive tool for imaging features inside living tissues. The extremely thin endoscope enables varieties of research and medical applications. https://www.glewengineering.com/engineers-add-new-updates-to-medical-advances-2019/
Conventional endoscopes use cameras and lights to capture images inside the body. Researchers developed alternative ways to capture images through optical fibers. Eliminating the need for bulky cameras, bulky components, for significantly thinner endoscopes. Despite their promise, however, these technologies suffer from limitations . For example, inability to tolerate temperature fluctuations or bending and twisting of the fiber.
Major Hurdle
Researchers developed tiny lensless endoscope, quiet a big major hurdle making these technologies practical, requiring complicated calibration processes. Many cases while the fiber is collecting images, the researchers added a thin glass plate. The tip of a coherent fiber bundle Just 150 microns thick. Optical fiber that is commonly used in endoscopy applications. Comparatively, coherent fiber bundle used for experimentation is 350 microns wide and consisted of 10,000 cores. https://www.glewengineering.com/brain-tumor-imaging-protein-in-scorpion-venom/
Illuminating the central fiber core, emitting a beam that is reflected back to the fiber bundle. Serving as virtual guide star for measuring how the light is transmitted. Known as the optical transfer function, providing crucial data, the system uses to calibrate itself.
Key Component: Researchers Developed Tiny Lensless Endoscope
Researchers developed tiny lensless endoscope key components of the new setup, a spatial light modulator. Used to manipulate the direction of the light, therefore, enabling remote focusing. The spatial light modulator compensates the optical transfer function and images on the fiber bundle. The back-reflected light from the fiber bundle is captured on the camera. Superposing a reference wave to measure the light’s phase. Positions of the virtual guide star determines the instrument’s focus, minimal focus diameter of approximately one micron. Researchers used an adaptive lens, a 2D galvometer mirror to shift the focus, enabling scanning at different depths. https://www.glewengineering.com/iris-recognition-as-biometric-identification/
The team tested their device, using a image a 3D specimen under a 140-micron thick cover slip. Scanning the image plane in 13 steps over 400 microns. An image rate of 4 cycles per second, the device successfully imaged particles, at the top and bottom of the 3D specimen. However, focus deteriorated as the galvometer mirror’s angle increased. Tiny endoscope searches small object , and the researchers suggest future work address this limitation. Using a galvometer scanner making a higher frame rate allowing faster image acquisition. https://www.mayoclinic.org/tests-procedures/capsule-endoscopy/about/pac-20393366
Researchers developed tiny lensless endoscope, approaching this way, enables both real time calibration and imaging with minimal evasiveness. Important for in-situ 3D imaging, lab on a chip based mechanical cell manipulation, deep tissue, vivo optogenetics, and keyhole technical inspections.