In this paper, a structural illumination based technology for microscopic surface topography measurement is investigated, in which only one shot structural illumination image is grabbed and a more efficient optical sectioned image reconstruction algorithm based on Hilbert transform was proposed. Compared with other methods, the technology can avoid strip artefacts problems of in-focus images resulting from the sinusoidal phases mismatch in spatial domain in conventional three-step phase-shifting since the phase-shifting steps decreases from three to one, and the measurement time is decreased effectively. The experimental testing is carried out to verify the feasibility and its measurement accuracy.
Currently the diode laser is widely used in the field of optoelectronics, especially in precise measurement based on laser-interferometry. Laser wavelength stability is a property that critical to the measurement. Since the laser wavelength is easy to be influenced by the environment and drive current, real-time monitoring and calibration of diode laser wavelength is extraordinary important for interferometry. In this paper, a real-time wavelength monitoring and calibration system for diode laser based interference measurement were developed. The experiment system was built and conducted to verify the feasibility of the system.
A novel carrier-suppressed return-to-zero frequency shift keying (CSRZFSK) transmitter that can operate at 40 Gb/s and above is proposed for the first time. The transmission characteristics of the CSRZFSK signal at 40 Gb/s compared with differential quadrature phase shift keying (DQPSK) signal and amplitude shift keying (ASK) signal are investigated under different dispersion management. Simulation results show that CSRZFSK has the best nonlinear tolerance and longest transmission distance when compared with DQPSK and ASK signals. A 40 Gb/s CSRZFSK signal gives only a 0.1 dB sensitivity penalty while DQPSK and ASK give 0.6 and 0.7 dB, respectively.
We propose a novel scheme for generation and detection of a 40 Gb/s binary frequency shift keying (FSK) signal. Multispan
transmission properties are numerically compared with return-to-zero (RZ) and differential phase shift keying
(DPSK) formats. Experimental demonstration shows that a 40 Gb/s FSK signal is transmitted over 50 km standard
single-mode fiber (SMF) with 0.8 dB penalty and over 12 dB resilience of span input power, clearly validating the
feasibility of this FSK modulation scheme. Transparent wavelength conversion for a 43Gb/s RZ-FSK signal is
successfully achieved by FWM in a SOA and in HNDSF. 2R regeneration is also to be purposefully observed in HNDSF
which results in limited over-all penalty after 100km transmission link.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.