Updated and expanded, the third edition of Photonics Rules of Thumb represents an evolving, idiosyncratic, and eclectic toolbox intended to allow any engineer, scientist, manager, marketeer, or technician (regardless of specialty) to make rapid and accurate guesses at solutions in a wide range of topics during system design, modeling, or fabrication. This book will help any electro-optics team to make quick assessments, generally requiring no more than a calculator, so that they can quickly find the right solution for a design problem.
This book has been assembled to introduce anyone working in the optics and photonics community to a wide range of critical topics through simple calculations, graphics, equations, and explanations. Useful design principles and rules, simple-to-implement calculations, and numerous graphs and tables of important basic information allow you to rapidly pinpoint trouble spots, ask the right questions at meetings, and are perfect for quick checks of last-minute specifications or performance feature additions. Offering a convenient arrangement according to specialty, this unique reference spans the spectrum of photonics. Eighteen chapters cover optics, atmospherics, radiometry, focal plane arrays, degraded visual environments, economics, and photogrammetry, as well as technologies related to security and surveillance systems, infrared, lasers, electro-optics, phenomenologies, self-driving vehicles, and many others.
The Single Aperture Far Infrared (SAFIR) observatory is a high priority mission for NASA and space astronomy. This ten-meter diameter telescope, operating at <10 Kelvin, will chart the formation of galaxies and elements in the early universe, map debris disks around stars to track hidden planets, and explore the chemistry of life in the universe. While baselined as an autonomously deployed telescope, we consider enabling factors that in-space operations would bring to this telescope - in particular, servicing opportunities that would dramatically increase the scientific lifetime and productivity of the observatory. The use of humans and robots to support and conduct servicing, at the operational site of Earth-Sun L2 and primarily at Earth-Moon L1, are considered, and the required capabilities are reviewed. SAFIR shares many characteristics of future large telescopes in space, and strategies developed for this strawman case are applicable for broader planning efforts.
Two recent meetings sponsored by NASA have helped define the in-space capabilities (technology, operations and infrastructure) necessary to enable and enhance future space missions. The activities preceded NASA's roadmapping efforts that occurred from the fall of 2004 to spring of 2005. These Loya Jirga meetings (using a Pashto expression for "grand council') involved about 100 representatives from industry, academia and government. Three mission concepts were used to guide the products of the meetings: manned missions to Mars, large serviceable space telescopes, and unmanned nuclear-powered missions to the outer planets. The deliberations produced roadmaps for the timing and type of developments needed to support these missions, the interconnections of capabilities with missions and other details that can be used to guide investment planning.
Recent advances in technology and materials science have enabled a number of large telescopes on Earth. Adaptation of these methods to space systems (beyond those being demonstrated in the James Webb Space Telescope (JWST)) might provide an equivalent breakthrough in science productivity, but only if important problems related to integration and performance testing are resolved. This paper proposes a program of technology and process development that can lead to efficient and reliable methods for in-space performance testing, thereby overcoming the limitations imposed by testing in gravity, the limited size of test chambers, the challenges of creating synthetic starlight sources and other factors. Considerations are given to the in-space facilities that are required and the need for human presence or tele-presence during the test interval. Both deployed and assembled space systems are considered. The paper addresses the optimal allocation of various test activities including the role of modeling, and functional and performance testing. Risk issues are defined, along with the impacts that such an integration and test path imposes on the telescope designer.
The principle goal of the paper is to define those parts of the test process that can (or must) be deferred until the system is in an operations-like environment and to define the processes and technologies that must be brought to maturity to assure that testing does not limit our ability to continue to upgrade our observational systems.
Many authors have endorsed the concept of assembly of large optics in space and have pointed out the technology needs for astronauts, infrastructure, robots and the observatories themselves. In this paper, we consider the technical issues associated with the integration and test in space of large optics during the next 15 years or so, when human activity is largely confined to low Earth orbit (LEO). We identify technical areas that need development and define a first version of the processes that might be used to create successful telescope missions that are tested in space. We identify a pathway that supports scalable solutions for very large systems necessary for imaging planets in other solar systems and other magnificent science. The investment in space integration and testing technology will return important dividends to designers of large space optics of the future. This approach to space optics testing is attractive because it overcomes the limits of ground testing associated with large test chambers, star simulators and the effects of gravity. It also directly benefits from, and supports, the technology and infrastructure investments about to be made by the new NASA Exploration Systems Enterprise, allowing both observatories and exploration missions to be assembled.
This reference book is a handy compilation of 300 cost-saving, think-on-your-feet photonics rules of thumb designed to save hours of design time. Within seconds you can accurately gauge the impact of a suggested design change on your project. It is the premiere collection of these valuable rules in a single, quick look-up reference.
These simple-to-implement calculations allow you to rapidly pinpoint trouble spots, ask the right questions at meetings, and are perfect for quick checks of last-minute specifications or performance feature additions. Offering a convenient alphabetical arrangement according to specialty, this unique reference spans the entire spectrum of Photonics. Eighteen chapters cover optics, electro-optics, optics of the atmosphere, radiometry, technologies related to security and surveillance systems, lasers, and many others. Copublished with McGraw-Hill.
Space-based, high resolution, Earth remote sensing systems, that employ large, flexible, lightweight primary mirrors, will require active wavefront correction, in the form of active and adaptive optics, to correct for thermally and vibrationally induced deformations in the optics. These remote sensing systems typically have a large field-of-view. Unlike the adaptive optics on ground-based astronomical telescopes, which have a negligible field-of-view, the adaptive optics on these space-based remote sensing systems will be required to correct the wavefront over the entire field-of-view, which can be several degrees. The error functions for astronomical adaptive optics have been developed for the narrow field-of-view correction of atmospheric turbulence and do not address the needs of wide field space-based systems. To address these needs, a new wide field adaptive optics theory and a new error function are developed. Modeling and experimental results demonstrate the validity of the wide field adaptive optics theory and new error function. This new error function, which is a new extension of conventional adaptive optics, lead to the development of three new types of imaging systems: wide field-of-view, selectable field-of-view, and steerable field-of-view. These new systems can have nearly diffraction-limited performance across the entire field-of-view or a narrow movable region of high-resolution imaging. The factors limiting system performance will be shown. The range of applicability of the wide field adaptive optics theory is shown. The range of applicability is used to avoid limitations in system performance and to estimate the optical systems parameters, which will meet the system’s performance requirements.
The Extra-Solar Planetary Imager (ESPI) is envisioned as a space based, high dynamic range, visible imager capable of detecting Jovian like planets. Initially proposed as a NASA Midex (NASA/Medium Class Explorer) mission (PI:Gary Melnick), as a space-based 1.5 x 1.5 m2 Jacquinot apodized square aperture telescope. The combination of apodization and a square aperture telescope reduces the diffracted light from a bright central source increasing the planetary to stellar contrast over much of the telescope focal plane. As a result, observations of very faint astronomical objects next to bright sources with angular separations as small as 0.32 arcseconds become possible. This permits a sensitive search for exo-planets in reflected light. ESPI is capable of detecting a Jupiter-like planet in a relatively long-period orbit around as many as 160 to 175 stars with a signal-to-noise ratio > 5 in observations lasting maximally 100 hours per star out to ~16 parsecs. We discuss the scientific ramifications, an overview of the system design including apodizing a square aperture, signal to noise issues and the effect of wavefront errors and the scalability of ESPI with respect to NASA's Terrestrial Planet Finder mission.
A NASA research contract (NAS1-00116) was awarded to Ball Aerospace & Technologies Corp. in January 2000 to study wide field-of-view adaptive optical systems. These systems will be required on future high resolution Earth remote sensing systems that employ large, flexible, lightweight, deployed primary mirrors. The deformations from these primary mirrors will introduce aberrations into the optical system, which must be removed by corrective optics. For economic reasons, these remote sensing systems must have a large field-of-view (a few degrees). Unlike ground-based adaptive optical systems, which have a negligible field-of-view, the adaptive optics on these space-based remote sensing systems will be required to correct for the deformations in the primary mirror over the entire field-of-view. A new error function, which is an enhancement to conventional adaptive optics, for wide field-of-view optical systems will be introduced. This paper will present the goals of the NASA research project and its progress. The initial phase of this research project is a demonstration of the wide field-of-view adaptive optics theory. A breadboard has been designed and built for this purpose. The design and assembly of the breadboard will be presented, along with the final results for this phase of the research project. Finally, this paper will show the applicability of wide field-of-view adaptive optics to space-based astronomical systems.
The Polar Stratospheric Telescope payload will be the prototype of a diffraction limited, large space telescope and will fly in the stratosphere to validate a number of new technologies that future large space telescopes will require. The telescope is a 6-m diameter, sparsely-filled array comprised on one 1.8-m and six 60-cm mirrors. Each mirror is a segment of an f/1.2 primary. The mirrors have an unequal spacing around the circumference which optimizes spatial coverage of the u,v plane. The mirror segments are coaligned and cophased by a combination of internal metrology and re-imaging of the pupil onto a small active mirror for the correction of piston and tilt errors. The telescope will be flown during the winter in a polar region where the tropopause is a factor of two lower than at lower latitudes, making the stratosphere accessible to tethered aerostats. The telescope is suspended approximately 100 m below a tethered aerostat flying at an altitude of about 12 km. The telescope body is stabilized gyroscopically with two reaction wheels, and fine guidance of the line of sight is provided by a fast steering mirror. The telescopes primary mirrors are at the ambient temperature of 190 to 220 K, and internal baffles and relay optics are cooled to 160 K to minimize the instrumental background in the near infrared.