David A Starkey

US Patent:

7843575, Nov 30, 2010

Filed:

Jan 4, 2008

Appl. No.:

11/969628

Inventors:

David T. Starkey - La Jolla CA, US

Assignee:

Midi9 LLC - La Jolla CA

International Classification:

G01B 11/14

US Classification:

356614

Abstract:

A scanner for a keyboard device having a reflective surface for each key has a sensor associated with each key that includes an LED and a photo-transistor. The LED is turned ON for a first measurement, followed by a second measurement with the LED turned off, and a subtraction of the second measurement from the first yields an illumination value for a key x. The LEDs and associated photo-transistors are sequentially enabled in groups of n, thereby eliminating optical interference. Each key x has associated correction parameters of LinRest(x) associated with illumination value with the key in the rest (up) position, LinDown(x) associated with illumination value with the key in the down position, TrebErr(x) associated with the reflectivity effect of one adjacent key(x+1), and BassErr(x) associated with the reflectivity effect of another adjacent key(x−1). By reading a single illumination value in combination with these correction parameters, the key position may be accurately extracted and the effect of ambient light and surrounding key interference removed.

US Patent:

8013234, Sep 6, 2011

Filed:

Sep 23, 2010

Appl. No.:

12/889403

Inventors:

David T. Starkey - La Jolla CA, US

Assignee:

Midi9 LLC - La Jolla CA

International Classification:

G10H 1/00

US Classification:

84724, 700108

Abstract:

A scanner for a keyboard device having a reflective surface for each key has a sensor associated with each key that includes an LED and a photo-transistor. The LED is turned ON for a first measurement, followed by a second measurement with the LED turned off, and a subtraction of the second measurement from the first yields an illumination value for a key x. The LEDs and associated photo-transistors are sequentially enabled in groups of n, thereby eliminating optical interference. Each key x has associated correction parameters of LinRest(x) associated with illumination value with the key in the rest (up) position, LinDown(x) associated with illumination value with the key in the down position, TrebErr(x) associated with the reflectivity effect of one adjacent key(x+), and BassErr(x) associated with the reflectivity effect of another adjacent key(x−). By reading a single illumination value in combination with these correction parameters, the key position may be accurately extracted and the effect of ambient light and surrounding key interference removed.

US Patent:

8159683, Apr 17, 2012

Filed:

Sep 24, 2010

Appl. No.:

12/889926

Inventors:

David T. Starkey - La Jolla CA, US

Assignee:

Midi9 LLC - La Jolla CA

International Classification:

G01B 11/14

US Classification:

356614

Abstract:

A scanner for a keyboard device having a reflective surface for each key has a sensor associated with each key that includes an LED and a photo-transistor. The LED is turned ON for a first measurement, followed by a second measurement with the LED turned off, and a subtraction of the second measurement from the first yields an illumination value for a key x. The LEDs and associated photo-transistors are sequentially enabled in groups of n, thereby eliminating optical interference. Each key x has associated correction parameters of LinRest(x) associated with illumination value with the key in the rest (up) position, LinDown(x) associated with illumination value with the key in the down position, TrebErr(x) associated with the reflectivity effect of one adjacent key(x+1), and BassErr(x) associated with the reflectivity effect of another adjacent key(x−1). By reading a single illumination value in combination with these correction parameters, the key position may be accurately extracted and the effect of ambient light and surrounding key interference removed.

US Patent:

50013394, Mar 19, 1991

Filed:

Mar 27, 1989

Appl. No.:

7/329008

Inventors:

David T. Starkey - San Diego CA
Anthony G. Williams - San Diego CA

Assignee:

Gulbransen, Inc. - San Diego CA

International Classification:

G01D 534

US Classification:

250229

Abstract:

A new, inexpensive and unobtrusive opto-electronic sensor which requires no manual adjustments after installation under the keys of the piano keyboard. Post-installation manual adjustments are unnecessary because a method embodied in a computer program and performed by a microprocessor digitally adjusts the operating ranges of the keys. After electronic adjustment, the opto-electronic sensors are scanned and sampled according to another portion of the method to determine the current key position and velocity. The key position and the velocity determined by the method are then transmitted in a MIDI compatible data stream.

US Patent:

46025456, Jul 29, 1986

Filed:

Jan 24, 1985

Appl. No.:

6/694373

Inventors:

David T. Starkey - San Diego CA

Assignee:

CBS Inc. - New York NY

International Classification:

G10H 700
G06F 738

US Classification:

84 101

Abstract:

A digital tone generator for a keyboard electronic musical instrument is described. The generator is of the waveshape memory type and repetitively interpolates between successive stored sample points thereby to effectively multiply the number of samples representing the waveshape so as to produce an output tone signal having reduced quantization error. Envelope errors are minimized by using cascade-connected multiplying digital-to-analog converters for multiplying the waveshapes derived from the interpolation with digital signals representative of an envelope waveshape. The system also includes a novel modification of a known multiplying digital-to-analog converter which greatly increases its speed of operation and makes possible the generation of clean output tone signals at the extremely high bit rates required to accomplish the interpolation.

US Patent:

52312836, Jul 27, 1993

Filed:

Nov 26, 1990

Appl. No.:

7/618154

Inventors:

David T. Starkey - San Diego CA
Anthony G. Williams - San Diego CA

Assignee:

Gulbransen, Inc. - San Diego CA

International Classification:

G01D 534

US Classification:

250229

Abstract:

A new, inexpensive and unobtrusive opto-electronic sensor which requires no manual adjustments after installation under the keys of the piano keyboard. Post-installation manual adjustments are unnecessary because a method embodied in a computer program and performed by a microprocessor digitally adjusts the operating ranges of the keys. After electronic adjustment, the opto-electronic sensors are scanned and sampled according to another portion of the method to determine the current key position and velocity. The key position and the velocity determined by the method are then transmitted in a MIDI compatible data stream.

US Patent:

49693859, Nov 13, 1990

Filed:

Dec 28, 1989

Appl. No.:

7/462871

Inventors:

Anthony G. Williams - San Diego CA
David T. Starkey - San Diego CA

Assignee:

Gulbransen, Inc. - Las Vegas NV

International Classification:

G01H 122
G01H 500

US Classification:

84656

Abstract:

A method for operating a digital synthesizer type of electronic musical instrument to rapidly make available digital oscillators to produce newly keyed notes even when all digital oscillators are currently active with previous assignments. The method contains a way of maintaining a record of the digital oscillator with the lowest amplitude, and reassigning this lowest amplitude digital oscillator to produce the new note on the rationale that the output of the lowest digital oscillator will be the least missed if an output has to be prematurely curtailed. Beside just a straight amplitude critereon, the method also allows for prioritizing some low amplitude outputs over others to make a more pleasing performance. The invention also includes an apparatus for performing the method.

US Patent:

49413872, Jul 17, 1990

Filed:

Jan 19, 1988

Appl. No.:

7/145093

Inventors:

Anthony G. Williams - San Diego CA
David T. Starkey - San Diego CA

Assignee:

Gulbransen, Incorporated - San Diego CA

International Classification:

G10H 700

US Classification:

84609

Abstract:

A digital synthesizer type electronic musical instrument that has the ability to automatically accompany a pre-recorded song with appropriate chords. The pre-recorded song is transposed into the key of C major, divided into a number of musical sequences, and then stored in a data structure. By analyzing the data structure of each musical sequence, the electronic musical instrument also can provide intelligent accompaniment, such as voice leading, to the notes that the operator plays on the keyboard.