This Small Business Innovation Research (SBIR) Phase II project conducts research and development of a unique laser technology that simultaneously provides a compact and low-cost alternative to laser guide star and polychromatic laser guide star sources. Guide star lasers are used in ground based adaptive-optics telescopes to provide high altitude, bright, point sources enabling adaptive near real-time correction for atmospheric aberrations. Adaptive optics systems rely on a combination of laser and natural guide-stars for tip-tilt correction. This limitation reduces the regions of space that can be explored due to the scarcity of natural guide-stars of adequate brightness. An elegant solution is to use polychromatic laser beacons comprising two closely spaced output wavelengths (569 and 589nm) to produce guide stars emitting, at distinctly disparate wavelengths (330 and 589nm). In 2008 a National Science Foundation committee of key adaptive optics scientists and decisions makers found astronomy is limited by the current state-of-the-art in lasers and that improving sodium laser beacons is critical to reaching stated astronomy science objectives. The research conducted under this SBIR project will produce optically pumped semiconductor lasers that can overcome technical limitations presented by more traditional guide star laser alternatives while simultaneously making guide star lasers more affordable.
The broader impact/commercial potential of this project will significantly impact the ability of observatories around the world to reach their scientific objectives by making available highly-reliable, low-cost guide star lasers. Currently, laser guide star systems are too expensive for all but the most well endowed observatories. Renowned experts and key decision makers in the field estimate the current laser guide star system cost at $100,000 per Watt of output power. The use of the laser technology to be produced can dramatically reduce the cost while simultaneously reducing the size weight and power required to operate the laser. In the near future, astronomical observatories will develop and field telescopes with much larger apertures. These and existing large aperture telescopes require multiple guide star lasers with a higher level of diversity, greater reliability while having lower per unit acquisition and maintenance costs. Successful development of the proposed product will positively impact astronomy, science and education by freeing up resources otherwise allocated to acquisition of expensive guide star systems. As a result, smaller observatories requiring a single system and large observatories requiring multiple laser guide stars will be able to execute their capital acquisition plans and achieve their science goals more rapidly.
Arete Associates furthered the development of Optically Pumped Semiconductor Lasers through execution of this grant. Specifically Arete demonstrated high power, narrow linewidth operation of OPSLs at a wavelength resonant with sodium D2a and D2b transitions. The resulting laser designs are compact, low cost and represent a new path forward for observatories to field rugged, affordable, guide star lasers. Guide star lasers provide the capability to employ modern adaptive optics on properly equipped telescopes. The outcomes of this project will significantly impact the ability of observatories around the world to reach their scientific objectives by making available highly-reliable, low-cost guide star lasers. Currently, laser guide star systems are too expensive for all but well-endowed observatories. Renowned experts and key decision makers in the field estimate the current laser guide star system cost at $100,000 per Watt of output power. The use of the laser technology to be produced can dramatically reduce the cost while simultaneously reducing the size weight and power required to operate the laser. In the near future, astronomical observatories will develop and field telescopes with much larger apertures. These and existing large aperture telescopes require multiple guide star lasers with a higher level of diversity, greater reliability while having lower per unit acquisition and maintenance costs. Successful development of the proposed product will positively impact astronomy, science and education by freeing up resources otherwise allocated to acquisition of expensive guide star systems. As a result, smaller observatories requiring a single system and large observatories requiring multiple laser guide stars will be able to execute their capital acquisition plans and achieve their science goals more rapidly.
