This study presents a new process to fabricate gapless triangular micro-lens array (GTMA). The process includes optical simulation with tracepro, UV lithography, photoresist reflow process, Ni electroplating and hot embossing technique. After photoresist triangular column array is defined using UV lithography, reflow process is applied to melt photoresist triangular column array into the shape of triangular micro-lens array. With this reflowed triangular micro-lens array, Ni is deposited and covered uniformly on the triangular micro-lens array using electroplating. The growth rate of Ni is controlled at electroplating current density of 1 Ampere Square Decimeter (ASD; A/dm2). After this electroplating process is finished, a mold of GTMA is obtained, which is served as primary mold. Subsequently, with passivation technique applied on this mold¡¦s surface, electroplating process is applied again to obtain a secondary mold. Next, this secondary mold is served as master for the subsequent hot embossing process to replicate the GTMA pattern onto polymeric material PMMA and PET sheet. The mold with stiffness and hardness plays an important role in GTMA hot embossing process. In addition, this GTMA used as optical film can offer a 100 % fill factor and a simulation of optical coupling efficiency of 66.7% to improve luminance of backlight module (BLM). In addition, this study presents the fabricated molds of GTMA with different aspect-ratio about 0.109 and 0.133. The optical measurement of BLM shows that this optical film of GTMA pattern with aspect-ratio about 0.109 can increase 15.1% of luminance and with aspect-ratio about 0.133 can increase 22.1% of luminance.

Digital cameras are increasingly used for measurement tasks within engineering scenarios, often being part of metrology platforms. Existing cameras are well equipped to provide 2D information about the fields of view (FOV) they observe, the objects within the FOV, and the accompanying environments. But for some applications these 2D results are not sufficient, specifically applications that require Z dimensional data (depth data) along with the X and Y dimensional data. New designs of camera systems have previously been developed by integrating multiple cameras to provide 3D data, ranging from 2 camera photogrammetry to multiple camera stereo systems. Many earlier attempts to record 3D data on 2D sensors have been completed, and likewise many research groups around the world are currently working on camera technology but from different perspectives; computer vision, algorithm development, metrology, etc. Plenoptic or Lightfield camera technology was defined as a technique over 100 years ago but has remained dormant as a potential metrology instrument. Lightfield cameras utilize an additional Micro Lens Array (MLA) in front of the imaging sensor, to create multiple viewpoints of the same scene and allow encoding of depth information. A small number of companies have explored the potential of lightfield cameras, but in the majority, these have been aimed at domestic consumer photography, only ever recording scenes as relative scale greyscale images. This research considers the potential for lightfield cameras to be used for world scene metrology applications, specifically to record absolute coordinate data. Specific interest has been paid to a range of low cost lightfield cameras to; understand the functional/behavioural characteristics of the optics, identify potential need for optical and/or algorithm development, define sensitivity, repeatability and accuracy characteristics and limiting thresholds of use, and allow quantified 3D absolute scale coordinate data to be extracted from the images. The novel output of this work is; an analysis of lightfield camera system sensitivity leading to the definition of Active Zones (linear data generation good data) and In-active Zones (non-linear data generation poor data), development of bespoke calibration algorithms that remove radial/tangential distortion from the data captured using any MLA based camera, and, a light field camera independent algorithm that allows the delivery of 3D coordinate data in absolute units within a well-defined measurable range from a given camera.