Patents by Inventor Nicolaas Roozen

Nicolaas Roozen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20070182516
    Abstract: The present invention relates to a magnetic resonance imaging (MRI) device. The basic components of an MRI device are the main magnet system, the gradient system, the RF system and the signal processing system.
    Type: Application
    Filed: March 11, 2005
    Publication date: August 9, 2007
    Applicant: Koninklijke Philips Electronics N.V.
    Inventors: Nicolaas Roozen, Adrian Toma, Georgo Angelis
  • Publication number: 20070176602
    Abstract: The present invention relates to a magnetic resonance imaging (MRI) device. The basic components of an MRI device are the main magnet system (2), the gradient system (3), the RF system and the signal processing system. According to the present invention, the magnetic resonance imaging (MRI) device has an eddy current shield system, wherein the eddy current shield system comprises at least one perforated eddy current screen (13, 14), and wherein the or each perforated eddy current screen (13, 14) is assigned to the main magnet system (2).
    Type: Application
    Filed: March 8, 2005
    Publication date: August 2, 2007
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Nicolaas Roozen, Martijn La Grange, David Biloen
  • Publication number: 20060273793
    Abstract: The invention provides a magnetic resonance imaging (MRI) device (21), comprising a diagnostic space (25), a main magnetic system (22) for generating a main magnetic field in said diagnostic space, a gradient magnetic coil system (23) comprising a gradient coil for generating at least one gradient of the main magnetic field, and noise reducing means (29, 32) for reducing noise that is generated as a result of vibrations of the gradient coil. The noise reducing means comprise a sound-absorbing panel (29) disposed between the gradient coil and the diagnostic space. The sound-absorbing panel (29) comprises channels having an open end and a closed end.
    Type: Application
    Filed: May 17, 2004
    Publication date: December 7, 2006
    Inventors: Nicolaas Roozen, Robert Kleihorst, Cornelis Leonardus Ham, Martijn La Grange
  • Publication number: 20060192556
    Abstract: The invention relates to an MRI system (1) comprising an examination volume (11), a main magnet system (13) for generating a main magnetic (field (B0) in the examination volume, a gradient magnet system (19) for generating gradients of the main magnetic field, and an anti-vibration system (39) for reducing vibrations of the gradient magnet system. According to the invention the anti-vibration system comprises a gyroscope (41) which is mounted to the gradient magnet system. As a result of the gyroscopic effect of the gyroscope, the vibrations of the gradient magnet system are effectively reduced. In an open type MRI system (1) according to the invention, a separate gyroscope (41, 43) is mounted to each of the two portions (21, 23) of the gradient magnet system (19), and each gyroscope has an axis of rotation (61) parallel to the main direction (Z) of the main magnetic field (B0).
    Type: Application
    Filed: March 11, 2004
    Publication date: August 31, 2006
    Inventors: Paul Harvey, Nicolaas Roozen, Cornelis Ham
  • Publication number: 20060006866
    Abstract: The invention relates to a magnetic resonance imaging (MRI) system (1) comprising an examination volume (11) in which a patient to be examined can be accommodated, a main magnet system (3) for generating a magnetic field having a main field portion (17) in the examination volume with a substantially constant magnetic field strength (B0), and a gradient magnet system (13) for generating gradients of the main field portion. The MRI system further comprises a damping member (25, 27) which is mounted to a part (5) of the MRI system susceptible to vibrations relative to the magnetic field during operation. Said damping member comprises an electrically conductive member (29, 35, 37) which is present in the magnetic field and in which eddy currents are generated as a result of said vibrations.
    Type: Application
    Filed: June 13, 2003
    Publication date: January 12, 2006
    Inventors: Nicolaas Roozen, David Biloen, Johannes Overweg
  • Publication number: 20050285594
    Abstract: The invention relates to a magnetic resonance imaging (MRI) system (1) comprising an examination volume (111), a main magnet system (13) for generating a main magnetic field (B0) in the examination volume in a Z-direction, a gradient magnet system (19) for generating gradients of the main magnetic field, and an anti-vibration system (33) for reducing vibrations of the gradient magnet system caused by a mechanical load (MX, MY) exerted on the gradient magnet system as a result of electromagnetic interaction between the main magnetic field and electrical currents in the gradient magnet system. According to the invention the anti-vibration system (33) comprises a balance member (39), which is coupled to the gradient magnet system (19) by means of an actuator system (51) and a coupling device (49) allowing displacements of the balance member relative to the gradient magnet system.
    Type: Application
    Filed: October 27, 2003
    Publication date: December 29, 2005
    Inventors: Nicolaas Roozen, Cornelis Leonardus Ham, Paul Harvey, Patrick Limpens
  • Publication number: 20050219026
    Abstract: The invention relates to a magnetic resonance imaging (MRI) system (1) comprising an examination volume (11), a main magnet system (17) for generating a magnetic field (B0) in the examination volume, and a gradient magnet system (25) for generating altering gradients of the magnetic field in the examination volume. The gradient magnet system is accommodated in a housing (31) having a main wall (33) facing the examination volume and a substantially conical wall (35) facing away from the examination volume. The main wall and the conical wall enclose a substantially angular tip portion (47) of the housing. In order to limit the level of the acoustic vibrations in and around the MRI system (1) caused by mechanical vibrations of the angular tip portion (47), the MRI system comprises a plurality of acoustic resonators (55) which each comprise an elongate resonance volume (57) with an open end (59) and a closed end (61) and a length (L) between the open end and the closed end.
    Type: Application
    Filed: April 11, 2003
    Publication date: October 6, 2005
    Inventors: Nicholaas Roozen, Martijn La Grange, Paul Harvey, Patrick Limpens, Cornelis Ham, Nicolaas Roozen, Martijn La Grange
  • Publication number: 20050156595
    Abstract: The invention relates to a magnetic resonance imaging (MRI) apparatus (1) comprising a main magnetic system (2) for generating a main magnetic field in an examination volume (7) which is enclosed by the main magnetic system (2). The MRI apparatus also comprises a magnetic gradient coil system (3) comprising gradient coils. The gradient coil system (3) is accommodated between the main magnetic system and the examination volume in order to generate gradients of the main magnetic field. The MRI apparatus also comprises a vacuum space (13). According to the invention, the gradient coil system only partly adjoins the vacuum space, that is, by way of its side which faces the examination volume. Thus, the examination volume is effectively shielded from acoustic vibrations caused by the gradient coil system in operation, while, in a specific embodiment, the end sides (22) of the gradient coil system are available for electrical and mechanical connections outside the vacuum space.
    Type: Application
    Filed: May 7, 2003
    Publication date: July 21, 2005
    Inventors: Cornellis Leonardus Gerardus Ham, Nicolaas Roozen, Patrick Limpens
  • Publication number: 20050068032
    Abstract: The invention relates to an open magnetic resonance imaging (MRI) magnet system (1) for use in a medical imaging system. The open MRI magnet system has two main coil units which are accomodated, at some distance from each other, in a first housing (2) and in a second housing (3), respectively. Between the two housings, an imaging volume (6) is present wherein a patient to be examined is placed. A gradient coil unit (9, 10) facing the imaging volume is present near a side of each of the two housings. Functional connections of the gradient coil units (9, 10), such as electrical power supply lines (13, 14) and cooling channels (15, 16) are provided in a central passage (4, 5) which is present in each of the two housings. As a result, these functional connections do not reduce the space in the imaging volume available for the patient.
    Type: Application
    Filed: November 20, 2002
    Publication date: March 31, 2005
    Inventors: Paul Harvey, Johannes Overweg, Cornelis Leonardus Ham, Nicolaas Roozen, Patrick Limpens