4.5 Article

650 GHz Imaging as Alignment Verification for Millimeter Wave Corneal Reflectometry

Journal

Publisher

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
DOI: 10.1109/TTHZ.2021.3140199

Keywords

Imaging; Cornea; Optical imaging; Physical optics; Optical sensors; Optical polarization; Couplings; Biological and medical imaging; clinical instruments; medical diagnostics; THz imaging of cornea

Funding

  1. National Eye Institute [5R01EY021590]
  2. Academy of Finland Research Project AGRUM through the Academy of Finland Programme Radiation Detectors for Health, Safety and Security (RADDESS) [327640]
  3. US National Eye Institute [5R01EY021590]
  4. Academy of Finland (AKA) [327640, 327640] Funding Source: Academy of Finland (AKA)

Ask authors/readers for more resources

This article presents a system concept for online alignment verification of millimeter-wave, corneal reflectometry. The system uses beam scanning to generate reflectivity maps of the cornea and compares them to a precomputed/measured template map to confirm alignment. The results show that the system can achieve accurate position measurement to a high degree.
A system concept for online alignment verification of millimeter-wave, corneal reflectometry is presented. The system utilizes beam scanning to generate magnitude-only reflectivity maps of the cornea at 650 GHz and compares these images to a precomputed/measured template map to confirm/reject sufficient alignment. A system utilizing five off-axis parabolic mirrors, a thin film beam splitter, and two-axis galvanometric mirror was designed, simulated, and evaluated with geometric and physical optics. Simulation results informed the construction of a demonstrator system which was tested with a reference reflector. Similarity metrics computed with the aligned template and 26 misaligned positions, distributed on a 0.5 mm x 0.5 mm x 0.5 mm mesh, demonstrated sufficient misalignment detection sensitivity in 23 out of 26 positions. The results show that positional accuracy on the order of 0.5 mm is possible using 0.462 mm wavelength radiation due to the perturbation of coupling efficiency via beam distortion and beam walk-off.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.5
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available