John Henry Lehman
Engineers in Boulder, CO
License number
Colorado 60153
Issued Date
Jan 20, 1994
Renew Date
Jan 20, 1994
Type
Engineer Intern
Address
Address
Nist, Boulder, CO 80303
Professional information
Domain Engineered Ferroelectric Optical Radiation Detector Having Multiple Domain Regions For Acoustic Dampening
US Patent:
6630671, Oct 7, 2003
Filed:
May 4, 2001
Appl. No.:
09/849959
Inventors:
John Henry Lehman - Boulder CO
John Andrew Aust - Boulder CO
John Andrew Aust - Boulder CO
Assignee:
The United States of America as represented by the Secretary of Commerce - Washington DC
International Classification:
G01J 500
US Classification:
2503383
Abstract:
A pyroelectric detector with significantly reduced microphonic noise sensitivity that includes a pyroelectric detector element constructed from a z-cut LiNbO or LiTaO electret. Selective domain reversal is accomplished in the electret by applying an electric field. Electrodes are attached to either surface of the electret spanning the domain reversed region and a portion of the original domain region to create areas of equal and opposite sensitivity. The detector is mounted in an electrically grounded container or housing. The detector may also be constructed having multiple detector regions to accommodate resonant acoustic frequencies of the electret, to function as a position sensor, or both. In other words, the position sensor has multiple domain regions that also accommodate acoustic frequencies. The detector may also be constructed having domain reversed regions placed on the electret in a periodic pattern having a geometry and spacing that is related to the acoustic impulse response of the electret.
Axial Translation Precision Position Post
US Patent:
5904066, May 18, 1999
Filed:
Feb 19, 1997
Appl. No.:
8/802607
Inventors:
John Henry Lehman - Boulder CO
Assignee:
The United States of America as represented by the Secretary of Commerce - Washington DC
International Classification:
F16H25/24
US Classification:
74 8915
Abstract:
A high-precision positioning post having alternating parallel cuts transving the center-line of the shaft body and which are perpendicular to the major axis of the shaft. The shaft further comprises a bearing rod internal to the shaft which is acted on by a screw. As the screw is turned, the bearing rod forces the end of the shaft to axially translate an object without rotation. This allows an object integral to the shaft or mounted on the shaft to be translated and located along the major axis of the shaft without rotation of the object. In an alternate embodiment the present invention may be used to isolate vibration by inclusion of dampers in the hollow shaft. A third embodiment uses the basic design as a vibration isolation mechanism for buildings.
Domain Engineered Ferroelectric Optical Radiation Detector
US Patent:
6114698, Sep 5, 2000
Filed:
Jan 30, 1998
Appl. No.:
9/016561
Inventors:
John Henry Lehman - Boulder CO
John Andrew Aust - Boulder CO
John Andrew Aust - Boulder CO
Assignee:
The United States of America as represented by the Secretary of Commerce - Washington DC
International Classification:
G01J 510
US Classification:
2503383
Abstract:
A pyroelectric detector with significantly reduced microphonic noise sensvity that includes a pyroelectric detector element constructed from a z-cut LiNbO. sub. 3 and LiTaO. sub. 3 electret. Selective domain reversal is accomplished in the electret by applying an electric field. Electrodes are attached to either surface of the electret spanning the domain reversed region and a portion of the original domain region to create areas of equal and opposite sensitivity. The detector is mounted in an electrically grounded container or housing. The detector may also be constructed having multiple detector regions to accomodate resonant frequencies of the electret or to function as a position sensor.
Vibration Dampener
US Patent:
6070850, Jun 6, 2000
Filed:
Jul 24, 1998
Appl. No.:
9/122247
Inventors:
John Henry Lehman - Boulder CO
Assignee:
The United States of America as represented by the Secretary of Commerce - Washington DC
International Classification:
F16M 1300
US Classification:
248622
Abstract:
The present invention is a high-precision positioning post having alternag parallel cuts transversing the center-line of the shaft body and which are perpendicular to the major axis of the shaft. The shaft further comprises a bearing rod internal to the shaft which is acted on by a screw. As the screw is turned, the bearing rod forces the end of the shaft to axially translate an object without rotation. This allows an object integral to the shaft or mounted on the shaft to be translated and located along the major axis of the shaft without rotation of the object. In an alternate embodiment the present invention may be used to isolate vibration by inclusion of dampers in the hollow shaft. A third embodiment uses the basic design as a vibration isolation mechanism for buildings.