Dynamic Micro-iris
The dynamic apertures, examined here, have a diameter of one to ten mm. Similar to the human eye, they are meant to reduce the capacity of incident light and increase the image’s sharpness through limitation on paraxial rays.
A first approach focuses on designing apertures on the basis of opto-fluidic structures. Here, two immiscible liquids are injected into spiral capillary channels – one of them being transparent the other opaque.
The curved contact surface of the two liquids (the meniscus) can be moved within the capillary by means of electrowetting such that the diameter of the transparent area is adjusted accordingly. In addition, the electrowetting process itself will be controlled optically (opto-electrowetting).
... in action |
A second approach focuses on apertures made of intrinsically conductive polymer layers (ICP). These polymers possess electrochromic features used to adjust the transmission of the aperture. In order to guarantee the transmission when the aperture is open, the electrodes need to be transparent (ITO layers). In extension of the mere aperture function, the use of such polymers also permits the spectral filtering of incident light.
Both types of apertures will be integrated into dynamic systems with tunable lenses. In order to retain the option of researching the dynamic filtering of spatial frequency, it is essential to characterize the systems’ general transmission properties.
The dynamic apertures, described here, can be applied in medical science as well as in imaging and lab devices.
The dynamic apertures, described here, can be applied in medical science as well as in imaging and lab devices.
Team Leaders
- Professor Henning Fouckhardt
TU Kaiserslautern
Department of Physics
email: fouckhar@physik.uni-kl.de - Professor Hans Zappe
Albert-Ludwigs University Freiburg
Department of Microsystems Engineering
email: zappe@imtek.uni-freiburg.de - Professor Egbert Oesterschulze
TU Kaiserslautern
Department of Physics
email: oester@physik.uni-kl.de
Relevant Publication
Müller, P.; Spengler, N.; Zappe, H. & Mönch, W.
An Optofluidic Concept for a Tunable Micro-iris
Journal of Microelectromechanical Systems JMEMS, 2010, 19, 1477-1484.