The following operators can be used to better focus your queries.
( ) , AND, OR, NOT, W/#
? single char wildcard, not at start
* multi char wildcard, not at start
(Cat? OR feline) AND NOT dog?
Cat? W/5 behavior
(Cat? OR feline) AND traits
Cat AND charact*
This guide provides a more detailed description of the syntax that is supported along with examples.
This search box also supports the look-up of an IP.com Digital Signature (also referred to as Fingerprint); enter the 72-, 48-, or 32-character code to retrieve details of the associated file or submission.
Concept Search - What can I type?
For a concept search, you can enter phrases, sentences, or full paragraphs in English. For example, copy and paste the abstract of a patent application or paragraphs from an article.
Concept search eliminates the need for complex Boolean syntax to inform retrieval. Our Semantic Gist engine uses advanced cognitive semantic analysis to extract the meaning of data. This reduces the chances of missing valuable information, that may result from traditional keyword searching.
An apparatus for convenient, reproducible and reliable characterization of optical waveguides using fiber excitation and a pneumatically- driven prism coupler is disclosed.
English (United States)
This text was extracted from a PDF file.
This is the abbreviated version, containing approximately
64% of the total text.
Page 1 of 1
Apparatus for Optical Characterization of Lightwave Waveguides
An apparatus for convenient, reproducible and reliable characterization of
optical waveguides using fiber excitation and a pneumatically- driven prism
coupler is disclosed.
A standard technique for experimentally determining the propagation
constants of guided modes in thin-film optical waveguides is prism coupling [*]. A
common problem encountered with the prism-coupling technique is the difficulty
in obtaining reproducible results even with the same sample. This is because the
prism is usually pressed against the waveguide substrate with a fine-threaded
screw. The pressure applied onto the prism directly affects the substrate-prism
gap and, thereby, the coupling efficiency. Such a mechanism is operator-
sensitive, and in the worst instance can crack the sample if excessive pressure is
These problems have been eliminated by an apparatus in which the prism is
held by a non-rotatable fixture which, in turn, is fastened to a frictionless slide to
assure only a linear motion. The fixture is pneumatically driven so that the
pressure on the prism can be controlled and monitored. Coupling efficiency can
be maintained to within 1% at a given applied pressure. The waveguide,
coupling prism with its associated fixture and holder for input fiber are placed on
a precision rotary table. The propagation constants of the guided waves are
determined from the angle between the mode-lines and the normal-to- p...