SBIR-STTR Award

The objective of this proposal is to develop an all solid-state inorganic glass optical limiter with low insertion loss in near infrared region from 800 to 1600nm. The proposed optical limiter is a nano-sized particle doped optical glass. It is an optical glass plate consisting of two layers: one contains nano-particles, and the other doesn’t. At low incident optical power or pulse energy, its transmission is high (better than 90%). At high incident optical power or pulse energy, its transmission will drop due to the high speed non-linear response of the nano-particles. The glass composition is specially designed to ensure that the optical limiter is radiation-resistant and can be used in space environment. In Phase I, we will design glass compositions, fabricate glass samples and introduce nano-particles into the glass by special glass technique. The limiting effect will be measured by Z-scan method both before and after the optical limiter is irradiated under gamma ray and proton to evaluate the effects in space radiation environment.

Benefits:
The Proposed optical limiters will be useful for military, civilian, and commercial communications satellite systems, such as military laser safety devices (for eyes and sensors), laboratory and medical laser safety devices/eyewear, optical data storage (three dimensional), compact disks, DVDs, three-dimensional holographic host materials, hidden security identifiers. They can also be useful for terrestrial free-space optical communications systems.

Keywords:
Optical limiter, laser threat, laser communications, ion-exchange, silver colloidal particle, nano-size particle, radiation resistance, all solid state optical limiter

The objective of this proposal is to develop a new type of all solid-state inorganic glass optical limiter with low insertion loss in the near infrared region from 800 to 1600nm. The proposed optical limiter is a nano-sized particle doped optical glass for protection of laser communication systems used in the space environment. In Phase I, the limiter has been designed as an optical glass plate consisting of two layers: one contains nano-particles, and the other doesn't. Very good optical limiting effect under 8 ns pulse Nd: YAG laser has been observed. In Phase II, we will optimize the chemical compositions of the optical limiter, improve our glass fabrication technique for the specially designed glass, optimize fabrication parameters for the limiter preparation to reduce linear optical loss and enhance the limiting effect. We will investigate the performance of the optical limiter for a digital optical communications system under irradiation with ultrashort laser pulses. The effects under space radiation environment on optical limiter performance using gamma ray irradiation as well as proton irradiation will be measured.

Keywords:
Optical Limiter, Laser Threat, Laser Communication