Microcamera May Pave the Way for Disposable Endoscopes

A manufacturing process developed by researchers at the Fraunhofer Institute for Reliability and Microintegration (Berlin) has yielded a microcamera the size of a grain of salt. Measuring just 1 × 1 × 1.2 mm, the miniature camera has a resolution of 62,500 pixels and can fit at the end of an endoscope. Moreover, it is inexpensive enough to produce that it could enable the development of disposable endoscopes.

Digital camera systems are essentially composed of a lens and a sensor. The latter converts an image into electrical signals while electrical contacts on top of it provide access to the signal; the contacts are located between the lens and the sensor.

Fabrication of these systems, according to the researchers, entails mass manufacturing of image sensors on a wafer; roughly 28,000 sensors are produced on a given wafer. Each sensor then has to be sawed out, wired, and mounted on the lens.

In an effort to streamline this process, the researchers altered the way in which the electrical contacts are accessed. "The trick lies in the fact that they do not reach the contacts of each individual image sensor via the side any more but rather, simultaneously, with all sensors via their reverse side while they are still connected as a wafer. That means that you no longer have to mount the individual lenses. Instead, you can connect them with the image sensor wafers as lens wafers. Only then is the stack of wafers sawed apart into individual microcameras," according to a Fraunhofer press release. The approach ultimately expedites the wiring process while reducing the overall size of the system.