摘要:
The present invention provides a method and apparatus for monitoring a UV curing lamp system to determine whether a UV-curable material passing through the curing lamp system is being properly cured. A thermal sensor is disposed to measure the temperature of gas being exhausted from a center tube of the UV curing lamp system. The center tube typically has nitrogen gas pumped into it to purge air from the center tube. The UV-curable material passes through the center tube. If a defect exists in the center tube, or if insufficient UV radiation is reaching the UV-curable material, the temperature of the gas stream exhausted from the center tube will drop. The temperature of the gas is compared to first and second threshold values, respectively, to determine whether a defect in the center tube exists or whether insufficient radiation is reaching the UV-curable material, respectively.
摘要:
An optical terminator 100 is designed to make end-to-end contact with an optical fiber whose end portion is held within a cylindrical ferrule. The optical terminator reduces reflections that occur when an optical path encounters an abrupt change in refractive index (e.g., when the end portion of the optical fiber encounters an air gap whose refractive index n.apprxeq.1.0). The optical terminator includes a generally cylindrical member 110 that projects from, and is supported by, a backbone member 120. The cylindrical member and the backbone member are molded from polymethyl methacrylate (PMMA) as a one-piece structure. PMMA provides a reflection of about -40 dB. Nevertheless, plastic materials having an index of refraction of 1.46.+-.0.06 produce reflections that are less than about -34 dB, which is acceptable in a large number of applications. Moreover, plastic materials having a glass-transition temperature (T.sub.g) that is higher than about 80.degree. C., exhibit minimum indentation creep under a compressive load at elevated temperatures. In one embodiment, the optical terminator 100 is spring loaded within a connector housing 45. In another embodiment, the spring 44 is eliminated and a connector housing is integrally molded with the optical terminator as a one-piece structure 70.
摘要:
An optical fiber connection device is disclosed that allows for in situ variable attenuation of a signal transmitted between two optical fibers. The connection device comprises an attenuator element fabricated with an inherently compliant, elastomeric material, preferably a silicone elastomer. The elastomeric properties of the attenuator element allow for varying the thickness of the attenuator element and thereby changing the level of attenuation in situ. Silicone elastomers are preferred for fabricating the attenuator element as applicants have discovered they may be index-matched to optical transmission fibers, have a high creep modulus, exhibit relatively constant mechanical properties over a broad range of temperatures, and are reliable upon exposure to varied environmental conditions.
摘要:
An optical fiber [10] having protective coating materials [14, 15], which surround an elongated strand of glass [12], is designed for improved strippability. Preferably, the optical fiber includes two layers (primary and secondary) of radiation-cured polymeric materials surrounding the glass fiber. The primary layer has an equilibrium (in-situ) modulus that resides within the range 120 to 500 psi. Additionally, the primary coating has a pull-out force (adhesion) that is less than 1.2 pounds per centimeter of length (lb/cm), and preferably resides within the range 0.5 to 1.0 lb/cm. It has been found that by increasing the equilibrium modulus, delamination resistance is increased. This has allowed designers to decrease pull-out force while maintaining a suitable delamination resistance. As a result, coating materials can now be stripped away from a glass fiber with little or no residue. This is particularly important in situations where a group of such fibers are bound together in an array [20] by a matrix bonding material [21].