Compact digital holoscope (CDH)

• Main Author: Koh, Raymond Chengwei
• Other Authors: Anand Krishna Asundi
• Format: Final Year Project
• Language: English
• Published: 2017
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/71290
• Institution: Nanyang Technological University

Digital holography microscopy (DHM) has increasingly become a method to obtain 3D information by scanning larger silicon wafer samples or micro-electromechanical system (MEMS) samples which do not fit into the field of view of a typical microscope. Due to the integration of a digital sensor array, such as a charge-coupled device (CCD) camera or digital camera, and other opto-mechanical components, the DHM microscope is able to overcome the issues plaguing traditional electronic microscopes. This report provides a study on the design and operations of the Compact Digital Holoscope (CDH) system housed in the Centre for Optical and Laser Engineering (COLE) lab in Nanyang Technological University (NTU). The current CDH system has lateral and axial resolutions of up to 6μm and 10nm respectively within a field of view of 4mm. It has a mechanical positioning stage allowing the samples to be adjusted in 3 axes. Such features allow the CDH system to be viable for industrial applications. However, the CDH is restricted in terms of field of view as the sample needs to be placed near the CCD in order to get high lateral resolution, which is an issue that can be looked into to further improve the equipment. Open source microscopy software is used to program the CDH system so as to reduce time and error due to manual inputs. The software has been internally programmed with all the necessary numerical algorithms such that it is user-friendly to layman. It is easily customizable and combines both image acquisition and analysis in one platform, making the microscopy process even more efficient.