Miniaturized camera system for an endoscopic capsule for examination of the colonic mucosa

Abstract

Today's standard procedure for the examination of the colon uses a digital endoscope located at the tip of a tube encasing wires for camera read out, fibers for illumination, and mechanical structures for steering and navigation. On the other hand, there are swallowable capsules incorporating a miniaturized camera which are more cost effective, disposable, and less unpleasant for the patient during examination but cannot be navigated along the path through the colon. We report on the development of a miniaturized endoscopic camera as part of a completely wireless capsule which can be safely and accurately navigated and controlled from the outside using an electromagnet. The endoscope is based on a global shutter CMOS-imager with 640x640 pixels and a pixel size of 3.6 mu m featuring through silicon vias. Hence, the required electronic connectivity is done at its back side using a ball grid array enabling smallest lateral dimensions. The layout of the f/5-objective with 100 degrees diagonal field of view aims for low production cost and employs polymeric lenses produced by injection molding. Due to the need of at least one-time autoclaving, high temperature resistant polymers were selected. Optical and mechanical design considerations are given along with experimental data obtained from realized demonstrators

Miniature optical planar camera based on a wide-angle metasurface doublet corrected for monochromatic aberrations

“…Such a camera would have 10× larger bandwidth compared to the miniature camera presented here, the same image plane intensity, but with 10× smaller image and 100× lower number of distinguishable pixels (94×94 pixels instead of 940×940). Compared to other miniature lenses reported previously [24][25][26] and Awaiba naneye camera (http://www.awaiba.com), the metasurface doublet offers significantly smaller f -number and better correction for monochromatic aberrations which lead to brighter images with higher resolution; however, they have larger chromatic aberration (i.e. narrower bandwidth).…”

Electrically tunable soft solid lens inspired by reptile and bird accommodation

“…mobile phone cameras and digital cameras in general [2]), biomedical devices (e.g. endoscopes [3], microscopes [4], lab-on-a-chips [5], ophthalmological instruments [6]), machine vision 4 and optical communication systems [7].…”