Abstract
The measurement of the second order nonlinear susceptibility of collagen in various biological tissues has potential applications in the detection of structural changes which are related to different pathological conditions. We investigate second harmonic generation in rat-tail tendon, a highly organized collagen structure consisting of parallel fibers. Using an electro-optic modulator and a quarter-wave plate, we modulate the linear polarization of an ultra-short pulse laser beam that is used to measure second harmonic generation (SHG) in a confocal microscopy setup. Phase-sensitive detection of the generated signal, coupled with a simple model of the collagen protein structures, allows us to measure a parameter γ related to nonlinear susceptibility and to determine the relative orientation of the structures. Our preliminary results indicate that it may be possible to use this parameter to characterize the structure.
| Original language | English |
|---|---|
| Pages (from-to) | 11-16 |
| Number of pages | 6 |
| Journal | Proceedings of SPIE - The International Society for Optical Engineering |
| Volume | 4276 |
| DOIs | |
| Publication status | Published - 2001 |
| Externally published | Yes |
| Event | Commercial and Biomedical Applications of Ultrashort Pulse Lasers; Laser Plasma Generation and Diagnostics - San Jose, CA, United States Duration: 2001 Jan 23 → 2001 Jan 23 |
Keywords
- Collagen
- Phase-sensitive detection
- Polarization modulation
- Second harmonic generation
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering