Patents Assigned to Sensors Unlimited, Inc.
  • Publication number: 20140312450
    Abstract: A method and structure of an image sensor device including a read out integrated circuit (ROIC) and a photodiode array (PDA). An embodiment may include a package substrate having a recess and a raised pedestal within the recess; a read out integrated circuit (ROIC) physically attached to the raised pedestal; a photodiode array (PDA) physically attached to the ROIC and electrically coupled therewith; and a printed circuit board (PCB) within the recess in the package substrate, wherein the PCB has an opening therein and the raised pedestal at least partially extends through the opening in the PCB.
    Type: Application
    Filed: March 6, 2014
    Publication date: October 23, 2014
    Applicant: Sensors Unlimited, Inc.
    Inventors: John Tagle, Dmitry Zhilinsky, Michael Liland, JR.
  • Patent number: 8860083
    Abstract: A low noise infrared photodetector has an epitaxial heterostructure that includes a photodiode and a transistor. The photodiode includes a high sensitivity narrow bandgap photodetector layer of first conductivity type, and a collection well of second conductivity type in contact with the photodetector layer. The transistor includes the collection well, a transfer well of second conductivity type that is spaced from the collection well and the photodetector layer, and a region of first conductivity type between the collection and transfer wells.
    Type: Grant
    Filed: May 13, 2013
    Date of Patent: October 14, 2014
    Assignee: Sensors Unlimited, Inc.
    Inventor: John Alfred Trezza
  • Publication number: 20140264437
    Abstract: A low noise infrared photo detector with a vertically integrated field effect transistor (FET) structure is formed without thermal diffusion. The FET structure includes a high sensitivity photo detector layer, a charge well layer, a transfer well layer, a charge transfer gate, and a drain electrode. In an embodiment, the photo detector layer and charge well are InGaAs and the other layers are InP layers.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicant: Sensors Unlimited, Inc.
    Inventor: Peter Dixon
  • Patent number: 8766159
    Abstract: In one aspect, the present invention provides photodetectors and components thereof having multi-spectral sensing capabilities. In some embodiments, photodetectors of the present invention provide a first photosensitive element comprising at least one accessway extending through the element and an electrical connection at least partially disposed in the accessway, the electrical connection accessible for receiving a second photosensitive element.
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: July 1, 2014
    Assignee: Sensors Unlimited, Inc.
    Inventors: John Trezza, Martin Ettenberg
  • Publication number: 20130183788
    Abstract: In one aspect, the present invention provides photodetectors and components thereof having multi-spectral sensing capabilities. In some embodiments, photodetectors of the present invention provide a first photosensitive element comprising at least one accessway extending through the element and an electrical connection at least partially disposed in the accessway, the electrical connection accessible for receiving a second photosensitive element.
    Type: Application
    Filed: March 5, 2013
    Publication date: July 18, 2013
    Applicant: Sensors Unlimited, Inc.
    Inventor: Sensors Unlimited, Inc.
  • Patent number: 8399820
    Abstract: In one aspect, the present invention provides photodetectors and components thereof having multi-spectral sensing capabilities. In some embodiments, photodetectors of the present invention provide a first photosensitive element comprising at least one accessway extending through the element and an electrical connection at least partially disposed in the accessway, the electrical connection accessible for receiving a second photosensitive element.
    Type: Grant
    Filed: June 23, 2009
    Date of Patent: March 19, 2013
    Assignee: Sensors Unlimited, Inc.
    Inventors: John Trezza, Martin Ettenberg
  • Patent number: 8218868
    Abstract: A method and an apparatus for enhancing images are provided. An input image generated by an imaging device, such as a short-wavelength infrared (SWIR) camera, sensor, or any other imaging device, is processed to produce an input histogram representing the distribution of pixel intensities in the input image. Histogram start and end points are determined, and a variable plateau profile is calculated depending upon the type of enhancement desired. The plateau profile could take on any desired shape or size, and two or more plateau regions could be included in the profile. The input histogram is clipped along the variable plateau profile. A cumulative histogram is constructed from the clipped histogram, and is normalized. The input image is then transformed into an enhanced output image using the normalized cumulative histogram as a look-up table.
    Type: Grant
    Filed: June 13, 2007
    Date of Patent: July 10, 2012
    Assignee: Sensors Unlimited, Inc.
    Inventors: Mark C. Stern, Thomas Sudol
  • Patent number: 7995125
    Abstract: A read out integrated circuit includes (ROIC) an array of pixel circuits, each of which has a first charge storage element electrically connected across an amplifier, and a second charge storage element having a selectively activated electrical connection across the amplifier. First and second gain select switches are configured to control the selectively activated electrical connection so as to selectively place the second charge storage element in electrical parallel with the first charge storage element and cause both the first and said second charge storage elements to store charge in response to light detected by said associated pixel. The circuit includes gain control column lines, each gain control column line configured to control a plurality of the first gain select switches belonging to pixel circuits in an associated column of the array.
    Type: Grant
    Filed: June 10, 2008
    Date of Patent: August 9, 2011
    Assignee: Sensors Unlimited, Inc.
    Inventor: Michael A. Blessinger
  • Publication number: 20110121423
    Abstract: A mask for use in making a planar PN junction in a semiconductor device includes a central mask opening and a plurality of spaced apart concentric mask openings surrounding the central mask opening. The concentric mask openings each have a width less than a maximum dimension of the central mask opening. The central mask opening can be circular and the concentric mask openings can have a ring-shape. The mask can be used to form openings in a wafer layer for introducing an impurity to dope that wafer layer.
    Type: Application
    Filed: November 25, 2009
    Publication date: May 26, 2011
    Applicant: Sensors Unlimited, Inc.
    Inventors: Keith Forsyth, Noah Clay
  • Publication number: 20090303363
    Abstract: A read out integrated circuit includes (ROIC) an array of pixel circuits, each of which has a first charge storage element electrically connected across an amplifier, and a second charge storage element having a selectively activated electrical connection across the amplifier. First and second gain select switches are configured to control the selectively activated electrical connection so as to selectively place the second charge storage element in electrical parallel with the first charge storage element and cause both the first and said second charge storage elements to store charge in response to light detected by said associated pixel. The circuit includes gain control column lines, each gain control column line configured to control a plurality of the first gain select switches belonging to pixel circuits in an associated column of the array.
    Type: Application
    Filed: June 10, 2008
    Publication date: December 10, 2009
    Applicant: Sensors Unlimited, Inc.
    Inventor: Michael A. Blessinger
  • Patent number: 7518095
    Abstract: A method and apparatus for providing non-linear, passive quenching of avalanche currents in Geiger-mode avalanche photodiodes (APDs) is provided. A non-linear, passive, current-limiting device is connected in series with the APD and a bias source. The non-linear, passive, current-limiting device rapidly quenches avalanche currents generated by the APD in response to an input photon and resets the APD for detecting additional photons, using a minimal number of components. The non-linear, passive, current-limiting device could comprise a field-effect transistor (FET), as well as a junction FET (JFET) a metal-oxide semiconductor FET (MOSFET), or a current-limiting diode (CLD) connected in series with the APD and the bias source.
    Type: Grant
    Filed: March 14, 2008
    Date of Patent: April 14, 2009
    Assignee: Sensors Unlimited, Inc.
    Inventor: Keith W. Forsyth
  • Patent number: 7385171
    Abstract: A method and apparatus for providing enhanced resolution in photodetector arrays is provided. In a first pass, pixels of a photodetector array are set to low input impedance values, and measurements of each pixel value are taken. In a second pass, selected pixels are set to high input impedance levels and remaining pixels set to low input impedance level, and measurements are taken at The low input impedance pixels. In a third pass, input impedance levels are reversed, and measurements are taken at the low input impedance pixels. A sequence of mathematical calculations are then performed on the measurements taken in the first, second, and third passes to produce half-pixel values for each of the pixels of the array, thereby doubling the resolution of the array without requiring additional circuitry or modification thereto.
    Type: Grant
    Filed: May 9, 2005
    Date of Patent: June 10, 2008
    Assignee: Sensors Unlimited, Inc.
    Inventor: Matthew T. O'Grady
  • Patent number: 7365299
    Abstract: A method and apparatus for providing flexible photodetector binning are provided. A photodetector having multiple pixels, such as a charged coupled device (CCD), a focal plane array (FPA), an active pixel sensor (APS), or other suitable detector, is provided. A desired bin area is produced in the array by setting at least one of the pixels of the array to a low input impedance level and remaining pixels to a high input impedance level, so that charges generated at the high input impedance pixels diffuse through the detector array to adjacent, low input impedance pixels. The charge is collected at the low input impedance pixels, and corresponds to light detected in the bin area. The impedances of the pixels can be varied to provide bins of desired shapes and/or geometries. The bin areas can extend partially over one or more pixels.
    Type: Grant
    Filed: May 9, 2005
    Date of Patent: April 29, 2008
    Assignee: Sensors Unlimited, Inc.
    Inventor: Matthew T. O'Grady
  • Patent number: 7361882
    Abstract: A method and apparatus for providing non-linear, passive quenching of avalanche currents in Geiger-mode avalanche photodiodes (APDs) is provided. A non-linear, passive, current-limiting device is connected in series with the APD and a bias source. The non-linear, passive, current-limiting device rapidly quenches avalanche currents generated by the APD in response to an input photon and resets the APD for detecting additional photons, using a minimal number of components. The non-linear, passive, current-limiting device could comprise a field-effect transistor (FET), as well as a junction FET (JFET) a metal-oxide semiconductor FET (MOSFET), or a current-limiting diode (CLD) connected in series with the APD and the bias source.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: April 22, 2008
    Assignee: Sensors Unlimited, Inc.
    Inventor: Keith W. Forsyth
  • Patent number: 7265846
    Abstract: Methods for detecting the presence or absence of ice or liquid water on surfaces are provided. In a first embodiment of the invention, a reflectance spectrum from a surface to be tested is measured using any suitable near-infrared optical system. The midpoint wavelength of the transition or step of the measured reflectance spectrum near 1.4 microns is calculated, and compared to a decision threshold wavelength. If the midpoint wavelength is less than the decision threshold wavelength, the presence of liquid water on the surface is indicated. If the midpoint wavelength is greater than the decision threshold wavelength, the presence of ice is indicated on the surface. In a second embodiment of the invention, at least three reflectance levels are measured at three wavelengths, and a dimensionless decision function is applied to the measured reflectance levels. Output of the decision function is compared to at least two pre-defined ranges.
    Type: Grant
    Filed: February 3, 2004
    Date of Patent: September 4, 2007
    Assignee: Sensors Unlimited, Inc.
    Inventor: Keith W. Forsyth
  • Patent number: 7122797
    Abstract: A detector including a base having a recess formed therein and a diaphragm generally extending across the recess. The detector further includes an infrared sensitive component or a piezoelectric or piezoresistive element located on, above or supported by the diaphragm. The diaphragm includes a material which is generally resistant to liquid chemical etchants and which has a thermal conductivity of less than about 0.005 Wcm?1K?1.
    Type: Grant
    Filed: September 9, 2003
    Date of Patent: October 17, 2006
    Assignee: Sensors Unlimited, Inc.
    Inventors: Shuwen Guo, Thomas Wiegele
  • Patent number: 6555890
    Abstract: An Indium/Gallium/Arsenide (InGaAs) detector having avalanche photodiodes (APD's) and p-i-n photodiodes on a single chip is provided. A method of fabricating the InGaAs device is also provided. The bias on the APD and p-i-n photodiodes are separately controlled.
    Type: Grant
    Filed: May 23, 2001
    Date of Patent: April 29, 2003
    Assignee: Sensors Unlimited, Inc.
    Inventors: J. Christopher Dries, Michael Lange
  • Patent number: 6518080
    Abstract: A method of fabricating low dark current photodiodes is provided. A multi-layer epitaxial structure is provided, wherein a contact epilayer forms the top-most layer of the structure. A diffusion mask is deposited on top of the contact layer, and at least one hole formed therein. Dopant is diffused through the hole and into both the contact epilayer and the underlying epitaxial structure, forming a doped region. A contact mask is then deposited, covering both the diffusion mask and the holes formed therein. The contact mask and contact epilayer are selectively etched, forming contact mesas and exposing portions of the underlying layers. A passivation coating, also serving as an anti-reflective coating and having uniform thickness, is deposited on top of the contact mesa and the exposed portions. Contacts and bond pads are then deposited, forming a complete photodiode.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: February 11, 2003
    Assignee: Sensors Unlimited, Inc.
    Inventors: Jonas Bentell, Michael Lange
  • Patent number: 5045691
    Abstract: An optical fiber rotary measurement sensor for flow meters and other mechanical devices incorporates a housing having an encoder disc mounted by a drive shaft for driven rotation, the drive shaft being driven by a flow meter mechanism or by any other mechanical device. The encoder forms evenly spaced light absorbing and light reflecting areas at the outer periphery thereof and optical fibers are positioned to project light onto and receive reflected light from the outer periphery of the encoder disc. An opto-electronic signal processor receives reflected light pulses from the reflective surface areas and translates the light pulses into electrical pulses. The electrical pulses are in turn input to electronic display circuitry for providing a digital, analog or other suitable display representative of the rotation of the encoder disc and thus representative of rotary output movement of the flow meter or other mechanical device.
    Type: Grant
    Filed: January 29, 1990
    Date of Patent: September 3, 1991
    Assignee: Sensors Unlimited Inc.
    Inventors: W. Paul Steward, Peter M. Sevick, Thomas J. Poorman