We have developed a miniature liquid lens component based on electro-wetting. It is designed to be plugged on a fix
focus camera module lens to provide both optical image stabilization (OIS) and auto-focus (AF) functions without any
mobile mechanical parts. The OIS/AF liquid lens component features a conical shape supporting the liquid interface in
order to maintain a stable optical axis and a multi-electrode design able to induce an average tilt of the liquid interface
when a bias voltage is applied to the different electrodes. The miniature size of the OIS/AF liquid lens component is well
adapted to imaging applications with ¼ inch, 1/3 inch and possibly 1/2.5 inch sensor formats. We will present general
rules for the optical design with an OIS/AF liquid lens. In this context, we will describe a simple calculation, based on
the well known Maréchal criterion, to estimate the optical wave front error requirement of an optical component
positioned in the aperture stop plane of an imaging lens design to perform images with a pixel resolution quality. We will
also present the principle of command of a multi-electrode liquid lens in order to perform AF and OIS functions with an
optimal image quality.
A new generation of liquid lenses based on electrowetting has been developed, using a multi-electrode design, enabling
to induce optical tilt and focus corrections in the same component. The basic principle is to rely on a conical shape for
supporting the liquid interface, the conical shape insuring a restoring force for the liquid liquid interface to come at the
center position. The multi-electrode design enables to induce an average tilt of the liquid liquid interface when a bias
voltage is applied to the different electrodes. This tilt is reversible, vanishing when voltage bias is cancelled. Possible
application of this new lens component is the realization of miniature camera featuring auto-focus and optical image
stabilization (OIS) without any mobile mechanical part. Experimental measurements of actual performances of liquid
lens component will be presented : focus and tilt amplitude, residual optical wave front error and response time.
The packaging of optical components (splitters, WDM, VOA, switches) used in telecommunication applications uses very often Fiber Arrays: it is indeed a very practical component to connect high channel count components (from 1 to 48 channels typically) to the outside world. These Fiber Arrays can be in different formats: standard, focusing, collimating, with single mode fiber or polarization maintaining fiber.
But the optical performance of the packaged component is primarily linked to the performance of the Fiber Array. Also, the reliability of the packaged component is mainly determined by the reliability of the Fiber Array, and the way it is attached to the component.
The optical performance includes mainly the fiber position error (Core Offset), which determines the insertion loss, but also the polishing induced parameters: polishing angles, surface planarity, fiber protrusion. Optical parameters are also important: excess loss, PDL, and return loss.
During the presentation will be related some measurement options, and some results.
The reliability of the fiber array is also very important, in order to meet the Telcordia qualification on the packaged product. Unfortunately, these standards, which apply to the packaged component, does not describe qualification procedures for Fiber Arrays, leaving some uncertainty on how to assess the reliability of the product. Different qualification options will be discussed, and some Telcordia qualification results shown.