Clinical Optics Research Lab – Indiana University School of Optometry

Welcome to CORL!

Posted on 3rd August 2018 by CORL

We are a group of scientists from around the world who participate in both basic and clinical studies designed to improve the visual quality of patients who are experiencing a variety of optical imperfections. Our diverse team has ongoing collaborations with colleagues in Spain, England, China as well as other labs at Indiana University.

CORL has helped design and evaluate many of the contact lenses and contact lens care products on the market today, helping millions of people around the world see.

We are always testing the newest ideas and products that may be available to you as a consumer in the future. To do this, however, we need your help by providing your feedback, such as how well you see, how comfortable you are, etc.

CORL performs cutting-edge translational clinical optics research. The goal of this research is to improve the vision and clinical care of patients by achieving the following aims:

Evaluate and predict the success of refractive interventions and visual corrections
Develop outcome measures to enhance a clinician’s ability to treat patients and the researchers ability to quantify improvements in care and determine causes for failures
Improve ocular diagnostics for the detection, diagnosis, and correction of corneal disease
Generate improvements in refractive interventions and visual corrections through controlled optical manipulations

We hope you find this website useful and informative. If you have any questions don’t hesitate to contact us.

2023 BCOR Photography Contest “Vision: More than Meets the Eye” Results

Posted on 10th April 2023 by maddy

Thank you to everyone that participated in the 2023 BCOR Photography Contest and congratulations to our finalists!

Vision: More than Meets the Eye

1st Place: “Wolf in cute clothing: this innocent looking “tree frog” is actually a poison dart frog!” by Dr. Nitya Murthy

2nd Place: “Eyes” by Yasser Alaa Mobarak

Honorable Mention: “Street Light : Through An Aging Eye” Vamsi Parimi

CORL Collaboration with the University of Houston

Posted on 20th March 2023 by maddy

Dr. Pete Kollbaum and Martin Rickert had a fun collaboration with some colleagues from the University of Houston. A retrospective analysis of real-world clinical data found no difference in the annualised axial length (AL) growth between peripheral defocus contact lenses and orthokeratology. Further, the AL progression from this clinical setting was consistent with those reported in randomised clinical trials. Overall, retrospective data may be useful for evaluating new treatments as myopia control becomes the standard of care.

Read the full article here

Optical Characterisation of Two Novel Myopia Control Spectacle Lenses

Posted on 8th February 2023 by maddy

Our article about Essilor Stellest and Hoya Visioncare MiYOSMART spectacle lenses for myopia control has been published in OPO: https://onlinelibrary.wiley.com/doi/full/10.1111/opo.13098

Key points:
– Distance image quality in the two myopia control spectacle lenses was reduced by the combined effects of defocus blur from the lenslets and diffraction blur from the fragmented distance optic.
– When viewing through the periphery of the two myopia control lenses, higher lenslet density (e.g., MiYOSMART) led to a larger observed decrease in image contrast.
– Although the lenslets in the MiYOSMART and Stellest myopia control spectacle lenses have different spatial distributions, average powers, uniformity of power and asphericities, clinical studies indicate similar efficacy.

Dr. Pete Kollbaum and Dr. Nitya Murthy Awarded Research Grant from the International Society for Contact Lens Research

Posted on 23rd January 2023 by maddy

Congratulations to Dr. Pete Kollbaum and Dr. Nitya Murthy for being awarded a research grant from the International Society for Contact Lens Research (ISCLR)! When asked about their project, the investigators held their protocol pretty close to the chest, but we could surmise that they are looking at the optics of myopia control lenses. Stay tuned for their presentation of this exciting work at the 2024 ISCLR meeting in Halifax Nova Scotia 8/18/24-8/23/24!

Participate in the 2023 Indiana University Borish Center Photography Contest

Posted on 20th January 2023 by maddy

We are pleased to announce the Indiana University Borish Center for Ophthalmic Research Photography Contest for 2023. The goal of this contest is to utilize artistic still images to tell a compelling story, which will help to foster interest and awareness of the importance of the eye and vision care to individuals and society. The theme for this year is “Vision: More than Meets the Eye” and we hope it inspires you to capture what this means to you.

Details of the contest can be found in the flyer above and entries can be submitted in the link below. Contest entries will be accepted from February 1 – April 1, 2023 and awards will be provided.

Submit Entry Here

2022 Photography Contest “Eye to Eye” Results

Posted on 15th April 2022 by maddy

Congratulations to Supriya Biswas on their first place entry “Mother’s Love.”

Runner-up:

Echo Tomlinson “Judgement”

Honorable Mentions:

Melissa Robertson “Windows to the Soul”

Grace Williams “Roommates”

Participate in the 2022 Indiana University Borish Center Photography Contest

Posted on 29th December 2021 by maddy

The goal of this contest is to utilize artistic still images to tell a compelling story, which will help to foster interest and awareness of the importance of the eye and vision care to individuals and society.

Details of the contest can be found in the flyer above and entries can be submitted in the link below. Contest entries will be accepted from February 1 – April 1, 2022 and awards will be provided.

Submit Entry Here

Fourier Analysis for Beginners by prof. Larry N. Thibos

Posted on 28th November 2021 by CORL

Natural philosophy is written in this grand book the universe, which
stands continually open to our gaze. But the book cannot be understood
unless one first learns to comprehend the language and to read the
alphabet in which it is composed. It is written in the language of
mathematics, and its characters are triangles, circles, and other geometric
figures, without which it is humanly impossible to understand a single
word of it; without these, one wanders about in a dark labyrinth.

Galileo Galilei, the father of experimental science.

Fourier analysis is ubiquitous. In countless areas of science, engineering, and mathematics one finds Fourier analysis routinely used to solve real, important problems. Vision science is no exception: today’s graduate student must understand Fourier analysis in order to pursue almost any research topic. This situation has not always been a source of concern.

The roots of vision science are in “physiological optics”, a term coined by Helmholtz which suggests a field populated more by physicists than by biologists. Indeed, vision science has traditionally attracted students from physics (especially optics) and engineering who were steeped in Fourier analysis as undergraduates. However, these days a vision scientist is just as likely to arrive from a more biological background with no more familiarity with Fourier analysis than with, say, French. Indeed, many of these advanced students are no more conversant with the language of mathematics than they are with other foreign languages, which isn’t surprising given the recent demise of foreign language and mathematics requirements at all but the most conservative universities. Consequently, a Fourier analysis course taught in a mathematics, physics, or engineering undergraduate department would be much too difficult for many vision science graduate students simply because of their lack of fluency in the languages of linear algebra, calculus, analytic geometry, and the algebra of complex numbers. It is for these students that the present course was developed.

To communicate with the biologically-oriented vision scientist requires a different approach from that typically used to teach Fourier analysis to physics or engineering students. The traditional sequence is to start with an integral equation involving complex exponentials that defines the Fourier transform of a continuous, complex-valued function defined over all time or space. Given this elegant, comprehensive treatment, the real-world problem of describing the frequency content of a sampled waveform obtained in a laboratory experiment is then treated as a trivial, special case of the more general theory. Here we do just the opposite. Catering to the concrete needs of the pragmatic laboratory scientist, we start with the analysis of real-valued, discrete data sampled for a finite period of time. This allows us to use the much friendlier linear algebra, rather than the intimidating calculus, as a vehicle for learning. It also allows us to use simple spreadsheet computer programs (e.g. Excel), or preferably a more scientific platform like Matlab, to solve real-world problems at a very early stage of the course.

With this early success under our belts, we can muster the resolve necessary to tackle the more abstract cases of an infinitely long observation time, complex-valued data, and the analysis of continuous functions. Along the way we review vectors, matrices, and the algebra of complex numbers in preparation for transitioning to the standard Fast Fourier Transform (FFT) algorithm built into Matlab. We also introduce such fundamental concepts as orthogonality, basis functions, convolution, sampling, aliasing, and the statistical reliability of Fourier coefficients computed from real-world data. Ultimately, we aim for students to master not just the tools necessary to solve practical problems and to understand the meaning of the answers, but also to be aware of the limitations of these tools and potential pitfalls if the tools are misapplied.

Related resources

Video Lecture: “Laplacians, Jacobians, and Gaussian curvature: A “deep-dive” into optical math” – prof. Larry N. Thibos.

Posted on 21st November 2021 by CORL

The lecture is prompted by a request for a deeper understanding of some of the vector algebra that is the foundation of the textbook method. That method is explained for optometric audiences in the attached paper, which will give you a sense of the “flavor” of the topic. Might not suit all tastes, but we must all learn to eat the bitter with the sweet 🙂 The lecture focuses on the geometrical properties of wavefronts that are used to compute the geometrical point-spread function. This is a very different problem from the more familiar Fourier optics calculation of the PSF based on physical optics. The math is actually easier for the geometrical optics method, but requires some familiarity with vector algebra concepts.