Artificial Apposition Compound Eye Research Articles

Design of artificial apposition compound eye with cylindrical micro-doublets

We present the design of a non-conventional optical system that uses cylindrical micro-doublets (CMD), integrated in an artificial apposition compound eye configuration (AACE). We show some designs of an ultra-thin objective inspired in fly eyes. These designs can give options to create new technologies that will process information in a different and effective way as usual. This process will be carried out by means of sampling the object with an array of multiple micro lenses using a certain value of the acceptance angle, and processing the optical signal to obtain partial images that will be part of a global one. The objective has the advantage of having a smaller size, a wider field of view, and an acceptable image quality compared with some conventional systems. Design parameters of the AACE and optical performance of the CMD are reported.

Artificial compound eye zoom camera

We demonstrate a highly compact image capturing system with variable field of view but without any mechanically moving parts. The camera combines an ultra-thin artificial apposition compound eye with one variable focal length liquid lens. The change of optical power of the liquid lens when applying a voltage results in a change of the magnification of the microlens array imaging system. However, its effect on focusing of the individual microlenses can be neglected due to their small focal length.

Artificial compound eye applying hyperacuity

Inspired by the natural phenomenon of hyperacuity, redundant sampling in combination with the knowledge about the impulse response of the imaging system is used to extract highly accurate information using a low resolving artificial apposition compound eye. Thus the implementation of a precise position detection for simple objects like point sources and edges is described.

Chirped arrays of refractive ellipsoidal microlenses for aberration correction under oblique incidence

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?.

Artificial apposition compound eye fabricated by micro-optics technology.

By exploring micro-optical design principles and technology, we have developed an artificial apposition compound eye. The overall thickness of the imaging system is only 320 microm, the diagonal field of view is 21 degrees, and the f-number is 2.6. The monolithic device consists of an UV-replicated microlens array upon a thin silica substrate with a pinhole array in a metal layer on the back side. The pitch of the pinholes differs from that of the lens array to provide individual viewing angle for each channel. Theoretical limitations of resolution and sensitivity are discussed as well as fabrication issues and compared with experimental results. A method to generate nontransparent walls between optical channels to prevent cross talk is proposed.

Design and analysis of apposition compound eye optical sensors

Methods are presented for designing and estimating the performance of artificial apposition compound eye optical sensors. Apposition compound eyes have been investigated for a wide range of applications from robotics to smart weapons. While artificial apposition compound eyes have been constructed and demonstrated, optical design issues and performance prediction for these systems have never been adequately addressed in the literature. Apposition compound eyes are a useful paradigm for applications where wide field of view is critical but high spatial resolution is not required. Natural arthropod compound eyes and their biological models are first scrutinized to give insight into designing and modeling artificial apposition compound eye optical sensors. Such sensors are shown to have comparable sensitivity to traditional single-aperture sensors for extended sources. A method for enhancing resolution over the extended-source case is demonstrated for single point sources. For the first time, the frequency response of an artificial apposition compound eye is addressed while taking into account the differences between artificial and natural ommatidia. Both a numercal integration technique for determining the contrast transfer function and a Fourier-transform modulation-transfer-function method are presented and validated with experimental results.