Abstract
Ultrafast lasers have found increasing use in scanning optical microscopy because of its very high peak power in generating multiphoton optical excitations. We are demonstrating that the multiphoton processes can be further extended to third harmonic generation (THG) and two-photon (2-p) excitation in the UVB range with broader tunablity enabled by a synchronously pumped optical parametric oscillator (OPO). The scanning nature of image acquisition process also greatly facilitates the incorporation of techniques in signal processing, which opens further possibilities. For example, the very short pulse width of ultrafast lasers allows excitation and sampling of photo-processes with extremely broad bandwidth. As such, radio frequency is excited as a contrast signal in imaging high speed photodiodes. In addition, dithering techniques that base on lock-in detection allows signal conditioning so that better signal to noise ratio can be resulted and features of high spatial frequency can be emphasized.
Original language | English |
---|---|
Pages (from-to) | 8-17 |
Number of pages | 10 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 5255 |
DOIs | |
State | Published - 2003 |
Event | Biomolecular Photonics and Multidimensional Microscopy - Wuhan, China Duration: 8 Jun 2003 → 11 Jun 2003 |
Keywords
- Dithering
- Laser scanning microscopy
- Optical beam induced current
- Optical parametric oscillator
- Radio frequency
- Second harmonic generation
- Third harmonic generation