12 Nov 2003
The pick of this week’s patent applications including plastic optical fiber that has low transmission and bending losses.
• Title: Plastic optical fiber
Applicant: Asahi Glass Company Limited, Japan
International application number: WO 03/091772
A Japanese company is trying to patent plastic optical fiber that it says has low transmission and bending losses over a broad wavelength region. The fiber contains three or more cores in a cladding. The company says that the key to its fiber’s performance is a core made from an amorphous polymer that contains fluorine and no C-H bond. It adds that the cladding, which is made from a similar material to the core, should have a refractive index that is in excess of 0.001 lower than that of the core.
• Title: GaSb-clad mid-infrared semiconductor laser
Applicant: Massachusetts Institute of Technology, US
International application number: WO 03/092132
The mid-infrared semiconductor laser described in application WO 03/092132 is said to have a low divergence angle and a high power efficiency. Several versions are discussed in the application. In one setup, the laser comprises two GaSb cladding layers surrounding an active core. According to the inventors, the refractive index of the two cladding layers should be less than but close to the refractive index of the core.
• Title: Method for controlling microbending induced attenuation losses in an optical fiber
Applicant: Pirelli S.P.A, Italy
International application number: WO 03/091781
Italian company Pirelli is trying to patent its method for controlling the attenuation losses caused by microbending in an optical fiber. The method involves coating the fiber with a polymer that has a hardening temperature lower than 10° and an equilibrium modulus lower than 1.5 MPa. A second polymeric material is used to cover the first coating layer.
• Title: Make-up applicator with LED light source
Applicant: Kuo-hwa Hwang, Taiwan
International application number: WO 03/090692
Putting make-up on when there is little or no light will no longer be a tricky skill to master, thanks to a Taiwanese inventor. Hwang’s idea involves mounting an LED inside a make-up applicator. “Surrounding the make-up applying means is an illumination means adapted to project the light axially outward,” said the inventor.