A research group from the Department of Bio and Brain Engineering, led by Professor Ki-Hun Jeong, has developed an ultrathin camera capable of taking images with high resolution, high contrast, and wide viewing angles. These characteristics of the micro-lens make it suitable for use in fields that require a compact camera, such as surveillance, medical devices, and mobile devices. The camera, with a mere 740 micrometer total track length, was inspired by the eye structure of a paper wasp species called Xenos peckii.
With the recently increased production of compact smart devices, the demand for a following compact imaging device has also grown substantially. However, traditional cameras use a structure of multi-layered lenses to reduce the distortion on images, making the thickness difficult to reduce. Moreover, existing insect-mimicking microlens arrays had a major issue with the image resolution due to the optical crosstalk between lenses — a phenomenon where scattered light causes distortions in the image.
As a solution, the researchers developed a lens structure that mimics the eye structure of the Xenos peckii, which has significantly more photoreceptors in their eyes compared to other insects. The researchers were able to resolve the optical crosstalk issue and create high resolution images by mimicking the pigment cells that insects have between lenses. These pigment cells are able to block the light found between the lenses.
The pigment cell mimic is produced using a process called photolithography, which allows the application of a very thin layer of the light-blocking substance between lenses. Furthermore, with appropriate lens placements, the researchers were able to reduce the thickness of the lens to a mere 0.74 mm. The camera captures multiple high-contrast images from the array of lenses and reconstructs them into a single high-resolution image.
Professor Jeong has expressed his excitement about developing a commercially viable compact camera, as well as his high hopes for its impact on micro and nanotechnology and use of such technology to contribute in the miniaturization of imaging related devices.