Optical: systems and elements – Extended spacing structure for optical elements – Extension of tubular element adjustable
Reexamination Certificate
2006-06-29
2009-08-04
Allen, Stephone B (Department: 2872)
Optical: systems and elements
Extended spacing structure for optical elements
Extension of tubular element adjustable
C250S225000, C356S437000, C359S484010
Reexamination Certificate
active
07570426
ABSTRACT:
Techniques for filtering light include, along a central optical axis, an entrance window; a first polarizer, a narrowband polarization-changing material, a second polarizer, and an exit window. The optical paths through the filter are substantively unscattered and pass through unstressed components between the polarizers. The polarization-changing material changes polarization for a narrow wavelength band on the order of about 0.01×10−9meters and does not condense on optical windows and polarizers during the operational lifetime. An aspect ratio, defined by a distance from the entrance window to the exit window divided by an optical aperture for the entrance window, is less than 4/1. This filter thus transmits light substantively unattenuated in the narrow wavelength band up to a maximum acceptance angle greater than 5 degrees. Combined with optics and imaging detectors, it is suitable for wide area surveillance, including daylight surveillance for combustion like forest fire and missile plume.
REFERENCES:
patent: 4435041 (1984-03-01), Torok et al.
patent: 4559445 (1985-12-01), Hedin et al.
patent: 5473162 (1995-12-01), Busch et al.
patent: 5502558 (1996-03-01), Menders
patent: 5731585 (1998-03-01), Menders et al.
patent: 6046808 (2000-04-01), Fateley
patent: 6128078 (2000-10-01), Fateley
patent: 6373558 (2002-04-01), Hasson
patent: 6392748 (2002-05-01), Fateley
patent: 6657195 (2003-12-01), Martin et al.
patent: 6677571 (2004-01-01), Clark et al.
patent: 6721096 (2004-04-01), Bruzzone et al.
patent: 6943868 (2005-09-01), Haig
patent: 6970201 (2005-11-01), Neil
patent: 6978064 (2005-12-01), Yoshida et al.
patent: 6985658 (2006-01-01), Smaglinski
patent: 7045783 (2006-05-01), Matveev
patent: 2005/0078729 (2005-04-01), Zhao
Chen et al, “Sodium-vapor Dispersive Faraday Filter,” Optics Letters, Jun. 15, 1993, pp. 1019-1021, vol. 18, No. 12, Optical Society of America.
Dick et al, “Ultrahigh-noise Rejection Optical Filter,” Optics Letters, Jun. 1, 1991, pp. 867-869, vol. 16, No. 11, Optical Society of America.
Sakurai et al, “Construction of Long-life Magneto-optical Filters for Helioseismology Observations,” unknown source, unknown publication date, but prior to Mar. 30, 2001.
Bythrow et al, “The Detection of Transient Optical Events at Narrowband Visible wavelength” APL Technical Digest, 1999, pp. 155-161, vol. 20, No. 2, The Johns Hopkins University Applied Physics Laboratory, US.
Gelbwachs, “Atomic Resonance Filters,” IEEE Journal of Quantum Electronics, Jul. 1988, pp. 1266-1277, vol. 24, No. 7, IEEE.
H. Lin and J.R. Kuhn, An Imaging, Tunable Magneto-Optical Filter, Solar Physics 122: 365-380, 1989.
N. Murphy, E. Smith, W. Rodgers, S. Jefferies, Chromospheric Observations in the Helium 1083NM Line-A New Instrument, Proc. Solar Wind 11-SOHO 16, Jun. 12-17, 2005.
Erlandson Robert E.
Hargis C. Bryon
Murphy Neil
Rodgers Wayne
Allen Stephone B
Chapel Derek S
Fasulo, II Albert J.
The Eddy Company
The Johns Hopkins University
LandOfFree
Apparatus and system for wide angle narrow-band optical... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and system for wide angle narrow-band optical..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and system for wide angle narrow-band optical... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4091132