Radiation imagery chemistry: process – composition – or product th – Imaging affecting physical property of radiation sensitive... – Making named article
Patent
1997-05-15
1999-08-31
Angebranndt, Martin
Radiation imagery chemistry: process, composition, or product th
Imaging affecting physical property of radiation sensitive...
Making named article
430 22, 430 30, 430290, 385 37, B02B 600
Patent
active
059452617
ABSTRACT:
A method of avoiding unwanted phase discontinuities between adjacent sections of a long Bragg grating written section-by-section in an optical fibre uses masks with alignment parts additional to their writing parts. Each alignment part is a replica of a portion of the writing part of the adjacent mask. Light of the same wavelength as used for writing grating sections excites stronger luminescence in regions of waveguide where there has been no irradiation induced raising of the refractive index than in regions where such index raising has occurred. Therefore, for such light directed through the alignment part of the mask and into the already-written previous section of the grating, the intensity of luminescent light propagating to an end of the waveguide varies according to how well or how badly the bright fringes produced by the mask register with the corresponding irradiated portions of the written Bragg grating. Fine adjustment of mask position is made to obtain the intensity corresponding to the desired level of registry before writing with this mask is commenced.
REFERENCES:
patent: 4807950 (1989-02-01), Glenn et al.
patent: 5157747 (1992-10-01), Aktins et al.
patent: 5367588 (1994-11-01), Hill et al.
Kashyap, R., et al., "Novel Method of Producing All Fibre Photoinduced Chirped Gratings," Electronics Letters, vol. 30, No. 12, Jun. 9, 1994, pp. 996-998.
Albert, J., et al., "Minimization of Phase Error in Long Fiber Bragg Grating Phase Masks Made Using Electron Beam Lithography," IEEE Photonics Technology Letters, vol. 8, No. 10, Oct. 1996, pp. 1334-1336.
Stubbe, R., et al., "Novel Technique for Writing Long Superstructured Fiber Bragg Gratings," Photosensitivity and Quadratic Nonlinearity in a Glass Waveguides Fundamentals and Applications, vol. 22, Sep. 9, 1995, pp. 285-287.
Paper by R Kashyap et al `Super-step-chirped fibre Bragg gratings`, Electronics Letters (Jul. 18, 1986) vol. 32, No. 15 pp. 1394-1396.
Paper by S L Gilbert `Comparison of UV-induced fluorescence and Bragg grating growth in optical fiber`, CWK5, CLEO '94, p. 244.
Paper by T Komukai et al `Fabrication of High Quality Long-Giber Bragg Grating by Monitoring 3.1 eV radiation (400nm) from GeO Defects`, IEEE photonics Technology Letters vol. 8 No. 11, Nov. 1996, pp.145-147.
Angebranndt Martin
Crane John D.
Northern Telecom Limited
LandOfFree
Creation of Bragg reflective gratings in waveguides does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Creation of Bragg reflective gratings in waveguides, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Creation of Bragg reflective gratings in waveguides will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2426283