Chip-scale diffraction phase microscopy

Edwards, Lonna D

Permalink

https://hdl.handle.net/2142/115597 Copy

Description

Title

Chip-scale diffraction phase microscopy

Author(s)

Edwards, Lonna D

Issue Date

2022-04-22

Director of Research (if dissertation) or Advisor (if thesis)

Goddard, Lynford

Doctoral Committee Chair(s)

Goddard, Lynford

Committee Member(s)

• Li, Xiuling
• Alleyne, Andrew
• Gruev, Viktor

Department of Study

Electrical & Computer Eng

Discipline

Electrical & Computer Engr

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

Ph.D.

Degree Level

Dissertation

Keyword(s)

• diffraction phase microscopy
• phase contrast microscopy
• interferometry
• Fresnel lens
• chip-scale

Abstract

The invention of the bright-field microscope helped scientists image cells as early as the seventeenth century; however, it was not until the 1930’s when Fritz Zernike invented the phase contrast microscope that transparent objects could be imaged without labeling. With the invention of photodetectors, quantitative phase imaging (QPI) developed, bringing with it sensitive and quick measurements containing height and refractive index analyses. Additionally, non-invasive imaging of transparent samples became possible. Though numerous QPI methods exist, diffraction phase microscopy (DPM) is notably advantageous. Its benefits include: 1) noise cancellation, 2) the ability to noninvasively image diverse samples, and 3) fast image acquisition. Due to its success in many applications, including cell imaging and semiconductor metrology, the author proposes scaling down the macro-scale system to implement the Mach-Zehnder-based interferometer on-chip. An on-chip model introduces additional advantages, including 1) space-saving properties, 2) reduction in material consumption and, thus, the cost of the optical system, and 3) reduction in the alignment error of the system. DPM on-chip also has the potential to be used in a new application: portable microscopy. If DPM on-chip is integrated as an add-on module to a cellphone camera, the image processing could be executed within a cellphone application. Such a system might prove useful in biological labs with limited space for testing instruments. It might also be beneficial in biology classrooms that attempt to spark curiosity within younger citizen scientists. The author will present optimized design parameters, fabrication techniques for key components, and potential applications for the device given its reduced field-of-view. Final results of the optimized system will be discussed followed by an explanation of future work that seeks to improve the outcome.

Graduation Semester

2022-05

Type of Resource

Thesis

Copyright and License Information

Copyright 2022 Lonna D. Edwards

Owning Collections