The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 28, 2005
Filed:
Mar. 12, 2002
Dale G. Fried, Dedham, MA (US);
Jean-francois Viens, Boston, MA (US);
James S. Foresi, Waltham, MA (US);
Maksim a Skorobogatiy, Brighton, MA (US);
Michael H. Lim, Cambridge, MA (US);
Dale G. Fried, Dedham, MA (US);
Jean-Francois Viens, Boston, MA (US);
James S. Foresi, Waltham, MA (US);
Maksim A Skorobogatiy, Brighton, MA (US);
Michael H. Lim, Cambridge, MA (US);
Cambrius Inc., Winchester, MA (US);
Abstract
By judicious engineering of grating parameters such as tooth shape, duty cycle and phase offset, the grating strengths and effective indices of the polarization modes of a grated waveguide are adjusted over a wide range of values to achieve a desired level of polarization sensitivity, or insensitivity. In the typical example, the physical geometry of the grating teeth is adjusted so that degenerate behavior (n=nand κ=κ) is obtained for two polarization modes; the effective refractive indices and grating strengths are matched for the TE and TM polarization modes. In the current embodiment the sidewall gratings are used in which the tooth profile is selected in order to equalize the grating strength for each polarization mode.