Design, Fabrication, and Characterization of Solid Tunable Micro Apertures
Date Issued
2016
Date
2016
Author(s)
Lyu, Cheng-Huan
Abstract
The thesis proposes an innovative way to fabricate solid tunable micro apertures. The aperture size can be changed continuously by applied different voltages. By appropriately combining two liquid materials, E7 and NOA-65, we make PDLC (Polymer-dispersed liquid crystal) which plays an important role in the transmittance of light in the device. In addition, we try to make a micro lens structure by two different methods, which are photolithography with Thermal reflow process , and the way to produce NOA-65 micro droplets by a nanoliter injector. With the change of the gap formed by the micro lens structure between two substrates, the various electric field will be yielded inside the device as applied constant voltage. At the same time, liquid crystals in the PDLC film direct in distinct angles due to the different electric field. And this status can make a difference of light transmittance on the surface of device. By the symmetric structure of micro lens, we can successfully fabricate an aperture with a circle shape and the aperture size can be enlarged or narrowed with various intensity of applied voltage. Finally, we use microscope with CCD to capture images of aperture and find out a valid way to measure the true aperture size on the device by switching focal planes. With the optimized program to deal with images taken by camera, we have a reliable way to find the relationship between the tendency of the various apertures and the increasing applied voltage. Besides, the different parameters in the fabrication of the device are completed. And we will make a comparison on different kinds of devices in the section of discussion.
Subjects
Micro Aperture
Solid Tunable
Type
thesis