摘要:
A device for detecting failures in a laser transmitting passage includes an inner tube (80) made from an optical hollow waveguide and having a first space (122) through which laser is transported, an outer tube (78) surrounding and extending along the inner tube, and a detector which recognizes a first condition in which the first space is fluidly disconnected from the second space and a second condition in which the first space is fluidly connected to the second space. The first and second conditions can be determined from a pressure, flow rate, gas concentration, ingredient of gas, or temperature in first or second space.
摘要:
An optical sensor (40) that provides a monotonic level-dependent output signal that varies smoothly and at an easily detectable rate over the entire length of the sensor includes first and second spaced waveguides (45, 50) extending along an axis, with each extending between its respective first and second ends. The first waveguide does not have surfaces contacting the liquid along the first waveguide's length. The second waveguide has at least a longitudinally extending portion of an outer surface in optical contact with the liquid. One or more web portions (50a, 50b, 50c) extend along and between both waveguides so that some of the light traveling along the first waveguide is coupled through the web portion(s) into the second waveguide. Light is injected into an end of the first waveguide (52), allowed to travel along the first waveguide, with a portion leaking into the second waveguide. Light is detected (55), with the amount representing the level of liquid.
摘要:
Methods and apparatus are disclosed for an intrusion detection system for secure fiber optic communication systems. A guard signal is transmitted over the optical fiber communication link and both the modal power and modal phase delay of this signal are monitored. Intrusions into the link for the purpose of intercepting information being transmitted, cause changes in the modal phase delay and power of the guard signal. These changes, when detected by the monitoring system, indicate the presence of an intruder. A fiber profile which is optimal for both transmission and intrusion detection purposes is described.
摘要:
A spectacle frame with ear bends each comprising an auricular front member connected to a temple, an auricular back member contactable with the back of the ear, and a connecting member for connecting the front member and the back member to be rotatable. The spectacle frame further comprises selective pressing means capable of changing a first state in which the back member presses the back of the ear with a second state in which the back member does not press the back of the ear.
摘要:
An optical device for measuring a level of a fluid in a container wherein a light conducting body having a top surface and a bottom surface is positioned within the container and into the fluid. A first end of the light conducting body and an oppositely disposed second end, preferably having stepped end surfaces, reflect and refract light in a predetermined manner based upon the fluid level in the container. A resulting brightness of the top surface is therefore inversely proportional to the level of the fluid. Such an optical device is particularly suited toward application to a vehicle fuel tank.