Abstract
The smoothness and accuracy of PMMA ablations with a prototype scanning photorefractive keratectomy (SPRK) system were evaluated by optical profilometry. A prototype frequency- quintupled Nd:YAG laser (Laser Harmonic, LaserSight, Orlando, FL) was used (wavelength: 213 nm, pulse duration: 15 ns, repetition rate: 10 Hz). The laser energy was delivered through two computer-controlled galvanometer scanners that were controlled with our own hardware and software. The system was programmed to create on a block of PMMA the ablations corresponding to the correction of 6 diopters of myopia with 60%, 70%, and 80% spot overlap. The energy was 1.25 mJ. After ablation, the topography of the samples was measured with an optical profilometer (UBM Messtechnik, Ettlingen, Germany). The ablation depth was 10 to 15 micrometer larger than expected. The surfaces created with 50% to 70% overlap exhibited large saw-tooth like variations, with a maximum peak to peak variation of approximately 20 micrometer. With 80% overlap, the rms roughness was 1.3 micrometer and the central flattening was 7 diopters. This study shows that scanning PRK can produce smooth and accurate ablations.
| Original language | English |
|---|---|
| Title of host publication | Proceedings of SPIE - The International Society for Optical Engineering |
| Editors | Jean-Marie Parel, Karen M. Joos, Pascal O. Rol |
| Pages | 57-60 |
| Number of pages | 4 |
| Volume | 2673 |
| State | Published - Jan 1 1996 |
| Event | Ophthalmic Technologies VI - San Jose, CA, USA Duration: Jan 27 1996 → Jan 28 1996 |
Other
| Other | Ophthalmic Technologies VI |
|---|---|
| City | San Jose, CA, USA |
| Period | 1/27/96 → 1/28/96 |
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ASJC Scopus subject areas
- Engineering(all)
Cite this
Evaluation of the smoothness and accuracy of scanning photorefractive keratectomy on PMMA by optical profilometry. / Manns, Fabrice; Rol, Pascal O.; Parel, Jean-Marie A; Schmid, Armin; Shen, Jin Hui; Matsui, Takaaki; Soderberg, Per G M D.
Proceedings of SPIE - The International Society for Optical Engineering. ed. / Jean-Marie Parel; Karen M. Joos; Pascal O. Rol. Vol. 2673 1996. p. 57-60.Research output: Chapter in Book/Report/Conference proceeding › Conference contribution
}
TY - GEN
T1 - Evaluation of the smoothness and accuracy of scanning photorefractive keratectomy on PMMA by optical profilometry
AU - Manns, Fabrice
AU - Rol, Pascal O.
AU - Parel, Jean-Marie A
AU - Schmid, Armin
AU - Shen, Jin Hui
AU - Matsui, Takaaki
AU - Soderberg, Per G M D
PY - 1996/1/1
Y1 - 1996/1/1
N2 - The smoothness and accuracy of PMMA ablations with a prototype scanning photorefractive keratectomy (SPRK) system were evaluated by optical profilometry. A prototype frequency- quintupled Nd:YAG laser (Laser Harmonic, LaserSight, Orlando, FL) was used (wavelength: 213 nm, pulse duration: 15 ns, repetition rate: 10 Hz). The laser energy was delivered through two computer-controlled galvanometer scanners that were controlled with our own hardware and software. The system was programmed to create on a block of PMMA the ablations corresponding to the correction of 6 diopters of myopia with 60%, 70%, and 80% spot overlap. The energy was 1.25 mJ. After ablation, the topography of the samples was measured with an optical profilometer (UBM Messtechnik, Ettlingen, Germany). The ablation depth was 10 to 15 micrometer larger than expected. The surfaces created with 50% to 70% overlap exhibited large saw-tooth like variations, with a maximum peak to peak variation of approximately 20 micrometer. With 80% overlap, the rms roughness was 1.3 micrometer and the central flattening was 7 diopters. This study shows that scanning PRK can produce smooth and accurate ablations.
AB - The smoothness and accuracy of PMMA ablations with a prototype scanning photorefractive keratectomy (SPRK) system were evaluated by optical profilometry. A prototype frequency- quintupled Nd:YAG laser (Laser Harmonic, LaserSight, Orlando, FL) was used (wavelength: 213 nm, pulse duration: 15 ns, repetition rate: 10 Hz). The laser energy was delivered through two computer-controlled galvanometer scanners that were controlled with our own hardware and software. The system was programmed to create on a block of PMMA the ablations corresponding to the correction of 6 diopters of myopia with 60%, 70%, and 80% spot overlap. The energy was 1.25 mJ. After ablation, the topography of the samples was measured with an optical profilometer (UBM Messtechnik, Ettlingen, Germany). The ablation depth was 10 to 15 micrometer larger than expected. The surfaces created with 50% to 70% overlap exhibited large saw-tooth like variations, with a maximum peak to peak variation of approximately 20 micrometer. With 80% overlap, the rms roughness was 1.3 micrometer and the central flattening was 7 diopters. This study shows that scanning PRK can produce smooth and accurate ablations.
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M3 - Conference contribution
SN - 0819420476
SN - 9780819420473
VL - 2673
SP - 57
EP - 60
BT - Proceedings of SPIE - The International Society for Optical Engineering
A2 - Parel, Jean-Marie
A2 - Joos, Karen M.
A2 - Rol, Pascal O.
ER -