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.
A method is described for sensing the velocity of a keyboard key for purposes of controlling sound attack.
English (United States)
This text was extracted from a PDF file.
This is the abbreviated version, containing approximately
82% of the total text.
Page 1 of 1
Musical Keyboard Velocity Sense Method
A method is described for sensing the velocity of a keyboard key for
purposes of controlling sound attack.
One limitation of most synthesized electronic musical keyboards when
compared to the mechanical piano is the lack of control of note attack, which is
related to the velocity of the key as it is pressed. The attack is an essential part
of the quality of sound and expression. This method of detecting the velocity of a
key on an electronic keyboard employs a single light emitter and detector, rather
than the more obvious scheme of multiple detectors.
In Fig. 1 an approach to velocity detection using two detectors is presented.
As the key is pressed, the light stimulus to detector "A" is broken, followed shortly
by a cutoff of light to sensor "B." By measuring the time between these events
and using the known separation of the detectors, the key velocity may be
determined. This approach has the disadvantage of requiring one light emitter
and two detectors per key, and may suffer from error due to mismatching of
In Fig. 2, an alternate detection scheme is illustrated using a single
emitter/detector pair. In the unactivated state, the opaque flag is not blocking the
light path. As the key is pressed, the flag moves into the light path, eventually
cutting off the beam to the detector. As the key moves further, the flag begins to
pass out of the beam until at full closure, the beam is restored. By measurin...