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A 6.5 inch diameter hyper-hemispherical silicon dome was developed on IRAD for an infrared countermeasures aircraft self-protection system. Having passed operational level environmental testing and many hours of flight performance, a prototype dome was subjected to MIL test requirements in simulated crash safety testing at the manufacturer's facility. Although the dome cracked during shock testing, it remained intact preserving aircraft integrity and actually passing safety requirements. This paper describes design requirements, stress analyses of the dome and its mounting, and test results including a forensic cause of failure study of the dome. The results add insight to the margins of safety normally applied to the stress analyses of brittle optical materials and examine actual cause of failure in the prototype part.

Based on laboratory investigations and flight test experiences we specify essential parameters and test requirements for airborne fiber optic components suitable for data busses in commercial and military aircraft. Functional and environmental characteristics and reliability requirements are described.

Test procedures and standards are currently being developed to validate and verify the effects of ionizing radiation on optical fiber components. The results from these tests can vary significantly with variations in the actual test setup and test requirements. It is important to recognize these sensitivities and monitor or control them to eliminate any inconsistencies in the test results. This paper will address the effects of ionizing radiation on optical fiber components, the development of test procedures and standards, and the comparison of a few test parameters to the final test results.

The primary focus of this paper is long wavelength infrared sensor calibration. The success or failure of a calibration program is determined long before calibration time by the quality of the prior sensor design and test program. Failure to adhere to any one of several important test principles can lead to difficulties in calibration and flight. If test and calibration are not given high priority during sensor design, flight performance may be compromised because calibration and functional testing will be difficult. A test and calibration facility is virtually required to accomplish the many different tests essential for sensor acceptance and calibration. A number of critical issues remain to be resolved, and a number of new requirements must be accommodated in future test and calibration facility design.

In conducting thermal/vacuum testing on a test article that is to operate at cryogenic temperatures (below 77 K, liquid nitrogen temperature), the designer is faced with unique problems peculiar to these temperatures. Care must be taken to account for these problems in the design of the test and its associated test equipment if a successful test program is to be achieved. These problems are often aggravated when the test article has special test requirements of its own that must be met. Frequently, trade-offs must be made. When the test article is an optical system, as it is in this case, the designer has especially difficult trade-offs to make. The design that evolves may involve compromise, but it must still insure that the desired cryogenic test conditions will be satisfactorily provided.

In the design and procurement of a high power laser system such as the Shiva Fusion Laser at LLNL, the optical components are the single most important aspect for optimum laser performance. The cost, schedule and quality of the optics are the driving parameters for the entire program and many factors are involved in controlling, monitoring and evaluating these parameters. These factors include (1) the procurement cycle, (2) knowledge of the vendors, (3) realistic specifications, (4) understanding of the fabrication process, (5) the quality control and test requirements. Guidelines and examples of the methods used in the procurement and qualification of the optics in Shiva will be presented.

The test and support of Electro-Optical (EO) systems introduces numerous unique demands that are not encountered when testing other types of equipment. This demand is amplified when test and support is undertaken using automated test techniques or Automatic Test Equipment (ATE). This latter case is increasingly becoming not only the method of choice but the method of necessity as EO systems become increasingly complex. This paper will acquaint the reader with some of the special requirements that are encountered when testing and/or supporting EO systems. It will concentrate on automatic testing and illustrate how the demands of EO testing were successfully satisfied particularly as regards software methods and techniques needed for EO systems using ATE within the DoD environment.

This paper describes work performed for the Ballistic Missile Defense Advanced Technology Center to assess the current state of optical sensor calibration and test facilities and to establish a recommended program for meeting projected BMDATC calibration and testing needs. Included in the paper are a summary of existing capabilities and calibration approaches, typical data produced during the assessment, and the recommended approach to satisfying the expected ground test requirements of astronomical infrared sensors.© (1978) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The use of a comprehensive data sheet to tabulate optical design data, specify tolerances and summarize system assembly, alignment and test requirements is explained.