Improvements of the resolution homogeneity of an ultra-thin artificial apposition compound eye objective are accomplished by the use of a chirped array of ellipsoidal micro-lenses. The array contains 130x130 individually shaped ellipsoidal lenses for channel-wise correction of astigmastism and field curvature occurring under oblique incidence. We present an analytical approach for designing anamorphic micro-lenses for such purpose based on Gullstrands equations and experimentally validate the improvement. Considerations for the design of the photolithographical masks for the micro-lens array fabrication by melting of photoresist cylinders with ellipsoidal basis are presented. Measurements of the optically performance are proceed on first realized artificial compound eye prototypes showing a significant improvement of angular resolution homogeneity over the complete field of view of 64.3?.

We propose a microoptical approach to ultra-compact optics for real-time vision systems that are inspired by the compound eyes of insects. The demonstrated module achieves 720p resolution with a total track length of 2.0 mm which is about 1.5 times shorter than comparable conventional miniaturized optics. The partial images that are separately recorded in multiple optical channels are stitched together to form a final image of the whole FOV by means of image processing. The microlens arrays are realized by microoptical fabrication techniques on wafer-level which are suitable for a potential application in high volume e.g. for consumer electronic products

Miniaturized imaging systems combining an ultra-compact form factor in combination with the ability of refocusing and depth imaging have gained much interest in the field of mobile imaging. Therefore, artificial compound eye cameras are an extremely promising approach for the realization of compact monolithic camera modules on wafer level. Up to now, their imaging performance was limited to low resolution in the range of VGA format according to fabrication constrains given by the established microoptical fabrication methods, namely the reflow of photoresist. In order to overcome these classical limitations, the use of refractive freeform arrays (RFFA) instead of conventional microlens arrays is inevitable. To enable high volume and cost efficient mass production of artificial compound eye cameras for mass markets like the consumer electronics industry, their fabrication on wafer level is essential, but has not been published up to now. We present a wafer level based process chain enabling the fabrication of these elements for the first time.

In this contribution, a microoptical imaging system is demonstrated that is inspired by the insect compound eye. The array camera module achieves HD resolution with a z-height of 2.0 mm, which is about 50% compared to traditional cameras with comparable parameters. The FOV is segmented by multiple optical channels imaging in parallel. The partial images are stitched together to form a final image of the whole FOV by image processing software. The system is able to acquire depth maps along with the 2D video and it includes light field imaging features such as software refocusing. The microlens arrays are realized by microoptical technologies on wafer-level which are suitable for a potential fabrication in high volume

The vast majority of cameras and imaging sensors relies on the identical single aperture optics principle with the human eye as natural antetype. Multi-aperture approaches – in natural systems so called compound eyes and in technology often referred to as array-cameras have advantages in terms of miniaturization, simplicity of the optics and additional features such as depth information and refocusing enabled by the computational manipulation of the system´s raw image data. The proposed imaging principle is based on a multitude of imaging channels transmitting different parts of the entire field of view. Adapted image processing algorithms are employed for the generation of the overall image by the stitching of the images of the different channels. The restriction of the individual channel´s field of view leads to a less complex optical system targeting reduced fabrication cost. Due to a novel, linear morphology of the array camera setup, depth mapping with improved resolution can be achieved. We introduce a novel concept for miniaturized array-cameras with several mega pixel resolution targeting high volume applications in mobile and automotive imaging with improved depth mapping and explain design and fabrication aspects