25 Jun 2004
The pick of this week's patent applications including a fluorescent tire.
• Title: Tire with fluorescent layers
Applicant: Michelin, France
International application number: WO 2004/050391
Michelin is patenting a tire containing a dye or pigment that fluoresces when exposed to ultraviolet light. The inventors say that shining an ultraviolet light onto the tire reveals the dyed regions and could aid retreading or alignment. In another instance, steel belts within the tire are marked using a fluorescent tape.
• Title: Laser-Air hybrid ultrasonic testing of railroad wheels
Applicant: The Johns Hopkins University, US
International application number: WO 2004/051256
Rail travel may become even safer if a non-contact system for detecting defects in railroad wheels proves successful. The device being patented by researchers at the Johns Hopkins University, US uses pulsed laser light to generate an ultrasonic wave in either a stationary or moving wheel. Transducers sense the acoustic signal emanating from the wheel and feed data into a signal processor. The system identifies the existence of wheel defects by analysing the acoustic signal.
• Title: Optical detector for the presence of gas bubbles in a liquid
Applicant: SC2N, France
International application number: WO 2004/051211
Researchers in France are patenting a device which uses a light source to detect gas bubbles in a liquid. Bubbles passing through the beam scatter light on to a detector placed at right angles to the light source. Successive measurements are analysed to determine variations in detected light intensity. A warning counter triggers when the proportion of bubbles in the liquid exceeds a maximum level.
• Title: Determining MFD of optical fibers
Applicant: Ericsson, Sweden
International application number: WO 2004/051334
Swedish mobile phone manufacturer Ericsson is patenting a method for determining the mode field diameter (MFD) of an optical fiber. The technique measures MFD by analysing thermal images of a hot fiber. When dopants diffuse out of the core, such as during heating of the fiber, the image of the core increases significantly. The hot image is formed by heating the optical fiber using an electrical discharge generated between electrodes. Measures of MFD help to improve the quality of loss estimation in fiber splices.