Physics MS Thesis Defense by Berk Zengin

KOÇ UNIVERSITY

GRADUATE SCHOOL OF SCIENCES & ENGINEERING

PHYSICS

MS THESIS DEFENSE BY BERK ZENGİN

Title: Instrumentation of an Opto-Digital Confocal Microscope and Development of a DMD-Based Imaging Setup

Speaker: Berk Zengin

Time: August 10, 2018, 10:00

Place: ENG 208

Koç University

Rumeli Feneri Yolu

Sariyer, Istanbul

Thesis Committee Members:

Prof. Alper Kiraz (Advisor, Koç University)

Asst. Prof. Aşkın Kocabaş (KoçUniversity)

Assoc. Prof. Oğuzhan Gürlü (Istanbul Technical University)

Abstract:

Confocal microscopy has become a vital tecnique for life sciences due to higher lateral and axial resolution it provides compared to standard epifluorescence microscopy. Improved axial resolution increases sectioning capabilities of the microscope, allowing for the observation of living specimens in three dimensions using image reconstruction.

Despite these, accessibility to confocal microscopes did not escalate in proportion to its usage around the globe. Therefore, in this thesis, we present a home-built laser scanning confocal microscope(LSCM) setup using commercially available equipment. The design of the setup was realized using a 488 nm laser beam, an inverted microscope, a photon multiplier tube(PMT) and optical/opto-mechanical parts including mirrors, lenses, beamsplitter, scan lens. In addition, X-Y axis galvanometer scanner was employed for beam steering. Instrumentation was made using a DAQ card and LabVIEW based software. For characterization purposes, confocal images of calibration samples were obtained.

As an alternative approach to standard LSCM, digital micromirror device(DMD) chip based optical scanner was implemented to confocal configuration for scanning the laser beam on specimen. Being cost-efficient and digital makes DMD-based scanners a promising candidate to be used in optical microscopy. Two different scanning algorithms were developed to modulate array of mirrors on DMD chip and images taken with different methods utilizing these algorithms were compared respectively.