PROBLEM STATEMENT 



The study, exploration, and utilization of hydrospace require the 

 use of instruments and devices which must be "packaged" in sealed housings 

 to protect them from the high-pressure seawater environment. While a few 

 such housings are available as off-the-shelf commercial items, the variety is 

 small, the cost high, and delivery time is frequently long. 



Lights for hydrospace illumination are a fundamental requirement 

 for either direct or indirect visual observation of any type of undersea 

 activity. Only in the shallowest portions of the sea, and then only during 

 sunny days, is the natural light adequate for most observational purposes. 

 The majority of lights and lighting systems require a transparent, pressure- 

 resistant housing for the proper functioning of the light-producing element. 

 Certain other devices such as light sensing or measuring instruments also 

 require pressure-resistant transparent housings. These requirements immedi- 

 ately point to the possible application of glass as a housing material since it 

 is transparent, has high compressive strength and in certain formulations is 

 resistant to thermal shock. Glass has an additional attraction in that it is a 

 nonmagnetic material and is transparent to many types of electromagnetic 

 radiation that are attenuated by metallic housing materials. The more 

 obvious advantages of these properties are the applicability of magnetic 

 and photo cell techniques for operating instruments in such packages and 

 for the transmission of data through the instrument housing walls without 

 the requirement for physical penetrations of the housing or end closures. 



STUDY OBJECTIVE 



This study is a continuation and extension of an investigation into 

 the applicability of commercially available off-the-shelf, dome-shaped glass 

 containers to the design of underwater lights. ''■^ Additional potential 

 applications for pressure-resistant glass housings caused the investigation to 

 be broadened to include larger commercial tubular glass shapes for both 

 lights and instrument housings. After evaluation of selected glass pipes of 

 various diameters and lengths, prototype light and instrument housings were 

 to be designed and fabricated. 



