Patent US2799987A successfully refreshed from Google Patents.
Patent US4184749A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4184749A Expired / Lapsed US ⏱️ 0.0 years remaining

Wide angle narrow bandpass optical filter system

Assignee: McDonnell Douglas Corp
•
Filing: 1978-06-22
•
Granted: 1980-01-22
•
Expires: 1998-06-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A spherical lens element and a concentric lens element receive light, in that order, from a wide field of view, and diverge all rays so that upon leaving said concentric element, the angles of all rays approximate that of radial lines. This light is then filtered through a concentric narrow bandpass filter to attenuate undesired background light, and is collected by a suitable light collector and detector. Apertures for selecting the field of view and F number are provided.

Inventors

  • 👤 Jack J. Grossman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 21:42
CPC Classifications
G; G02; G02B; G02B13/00; G02B3/00; G02B5/00; G02B5/20; G02B5/28; G02B5/284

Claims Analysis

Total Claims: 36
Claim 1
Independent Claim 123 words
A wide angle narrow bandpass lens and optical filter system comprising: a. at least one spherical lens for receiving light at a plurality of angles at the first surface of said spherical lens, and for focusing said light at a plurality of image points outside a second opposite surface of said spherical lens, b. at least one concentric lens comprising inner and outer surfaces, all points of each surface equally distant from said spherical lens center, positioned so that said image points are located between said second surface and said inner surface, and c. a filter, all points of said filter equally distant from said spherical lens center, positioned so that said concentric lens is located between said filter and said image points.
Claim 2
Dependent Claim 123 words
A wide angle narrow bandpass lens and optical filter system comprising: a. at least one spherical lens for receiving light at a plurality of angles at the first surface of said spherical lens, and for focusing said light at a plurality of image points outside a second opposite surface of said spherical lens, b. at least one concentric lens comprising inner and outer surfaces, all points of each surface equally distant from said spherical lens center, positioned so that said image points are located between said second surface and said inner surface, and c. a filter, all points of said filter equally distant from said spherical lens center, positioned so that said concentric lens is located between said filter and said image points.
Claim 3
Dependent Claim 18 words
The apparatus of claim 1 wherein said filter is attached to said outer surface of said concentric lens.
Claim 4
Dependent Claim 63 words
The apparatus of claim 1 wherein the centers of said spherical lens, said concentric lens and said filter are positioned in line, said spherical lens contains a groove, the plane of said groove being at right angles to said line, and further comprising a field stop aperture positioned within said groove adjustable to block a portion of light passing through said spherical lens.
Claim 5
Dependent Claim 31 words
The apparatus of claim 1 further comprising a field of view aperture positioned between said spherical lens and said concentric lens to block a portion of light entering said concentric lens.
Claim 6
Dependent Claim 56 words
An optical system as described in claim 3 further comprising: a. at least one second adjustable aperture positioned at the focal point of said first lens for selectively blocking light transmitted by said first lens whereby light transmitted by said first lens at unwanted angles to the axis of the focal plane may be selectively blocked.
Claim 7
Dependent Claim 22 words
An optical system as described in claim 5 wherein said optical filter is attached to the convex surface of said second lens.
Claim 8
Dependent Claim 20 words
An optical system as described in claim 6 further comprising: a. means for detecting light which passes through said filter.
Claim 9
Dependent Claim 33 words
An optical system as described in claim 7 further comprising: a. means for collecting the light which passes through said filter, and b. means for directing the collected light to said detecting means.
Claim 10
Dependent Claim 30 words
An optical system as described in claim 8 wherein said first aperture is planar and said second aperture is a hollow spherical section concentric with said first and second lens.
Claim 11
Dependent Claim 90 words
A wide angle narrow bandpass optical filter having elements positioned along a line in the following positional order, a first lens element comprising a first surface convex toward a light source defining a spherical surface about a first point on said line, and a second surface convex away from the light source defining a spherical surface about a second point on said line, a second lens comprising inner and outer surfaces concentric with said second surface, and a filter concentric with said second surface and said inner and outer surfaces.
Claim 12
Dependent Claim 90 words
A wide angle narrow bandpass optical filter having elements positioned along a line in the following positional order, a first lens element comprising a first surface convex toward a light source defining a spherical surface about a first point on said line, and a second surface convex away from the light source defining a spherical surface about a second point on said line, a second lens comprising inner and outer surfaces concentric with said second surface, and a filter concentric with said second surface and said inner and outer surfaces.
Claim 13
Dependent Claim 18 words
The apparatus of claim 10 wherein said filter is attached to said outer surfaces of said second lens.
Claim 14
Dependent Claim 31 words
The apparatus of claim 10 further comprising a field stop aperture means positioned between said first and second surfaces to block a portion of light passing through said first lens element.
Claim 15
Dependent Claim 22 words
The apparatus of claim 12 further comprising a field of view aperture means positioned between said second surface and said inner surface.
Claim 16
Dependent Claim 35 words
The apparatus of claim 13 wherein said field stop aperture means is adopted to provide a circular field stop aperture centered about and perpendicular to said line, said field stop aperture having a variable radius.
Claim 17
Dependent Claim 48 words
The apparatus of claim 14 wherein said field of view operative means comprises an opaque surface concentric to, and located between, said second and inner surfaces having a field of view aperture centered about and perpendicular to said line, said field of view aperture having a variable radius.
Claim 18
Dependent Claim 18 words
The apparatus of claim 15 further comprising a detector means for collecting the light passing through said filter.
Claim 19
Dependent Claim 38 words
The apparatus of claim 16 wherein said detector means comprises: a mirror for reflecting all light passing through said filter onto a generally localized region, and at least one detector located in said region for detecting said light.
Claim 20
Dependent Claim 40 words
The apparatus of claim 16 wherein said mirror is ellipsoidal and all light passing through said filter passes through a focal point of said ellipsoidal mirror and said detector is located generally at the opposite focal point of said mirror.
Claim 21
Dependent Claim 94 words
An optical lens and filter system for receiving a narrow band width of scattered spectrals signals comprising: a. means for collecting light over a wide angle, including at least one first lens for converging light received at a plurality of angles to a plurality of corresponding focal points, b. an optical filter, and c. means for directing the collected light normal to the surface of said filter, including at least one second lens and wherein said first lens is spherical and said second lens is a hollow spherical section concentric with said first lens.
Claim 22
Dependent Claim 94 words
An optical lens and filter system for receiving a narrow band width of scattered spectrals signals comprising: a. means for collecting light over a wide angle, including at least one first lens for converging light received at a plurality of angles to a plurality of corresponding focal points, b. an optical filter, and c. means for directing the collected light normal to the surface of said filter, including at least one second lens and wherein said first lens is spherical and said second lens is a hollow spherical section concentric with said first lens.
Claim 23
Dependent Claim 74 words
An optical system as described in claim 19 wherein said first lens contains an annular groove parallel to the focal plane thereof and wherein said system further comprises: a. a first adjustable aperture received by said groove for varying the ratio of the focal length to the aperture, whereby adjustment of the first aperture changes the f number of the system and allows control of the intensity of light transmitted by said first lens.
Claim 24
Dependent Claim 86 words
An optical lens and filter system for receiving and filtering a narrow band width of scattered spectral signals comprising: a. a spherical first lens having an annular groove parallel to the focal plane, b. an adjustable first aperture received by said groove, c. a second lens defining a hollow spherical section concentric with said first lens, d. at least one second aperture positioned between said first lens and said second lens and concentric therewith, and e. at least one dielectric filter concentric with said second lens.
Claim 25
Dependent Claim 86 words
An optical lens and filter system for receiving and filtering a narrow band width of scattered spectral signals comprising: a. a spherical first lens having an annular groove parallel to the focal plane, b. an adjustable first aperture received by said groove, c. a second lens defining a hollow spherical section concentric with said first lens, d. at least one second aperture positioned between said first lens and said second lens and concentric therewith, and e. at least one dielectric filter concentric with said second lens.
Claim 26
Dependent Claim 39 words
An optical lens and filter system as described in claim 21 wherein the indexes of refraction for said first and second lens are equal and the ratio of the index thereof to the environmental index is 2.0 or less.
Claim 27
Dependent Claim 31 words
An optical lens and filter system as described in claim 21 wherein the ratio of the index of refraction of the first lens to the scattering environment is 2 or less.
Claim 28
Dependent Claim 24 words
An optical lens and filter system as described in claim 21 wherein the focal length of said first lens terminates at the second aperture.
Claim 29
Dependent Claim 88 words
An optical lens and filter system comprising: a. a first converging lens for receiving light, b. a second converging lens spaced apart from said first lens for directing light received from said first lens toward a focal point, c. a third lens concentric with the second lens for receiving the light as it diverges from the focal point and for directing said light toward a radius depending from concentric center, and d. a dielectric filter concentric with said third lens for filtering the light transmitted by such lens.
Claim 30
Dependent Claim 88 words
An optical lens and filter system comprising: a. a first converging lens for receiving light, b. a second converging lens spaced apart from said first lens for directing light received from said first lens toward a focal point, c. a third lens concentric with the second lens for receiving the light as it diverges from the focal point and for directing said light toward a radius depending from concentric center, and d. a dielectric filter concentric with said third lens for filtering the light transmitted by such lens.
Claim 31
Dependent Claim 28 words
An optical system as described in claim 25 further comprising: a. at least one adjustable aperture between said second and third lens for limiting the field of view.
Claim 32
Dependent Claim 41 words
An optical system as described in claim 26 wherein there are a plurality of adjustable apertures for limiting the field of view along a plurality of axes about the central axis of the focal plane each individually selectable along corresponding axes.
Claim 33
Dependent Claim 21 words
An optical system as described in claim 27 wherein said apertures are positioned at the focal point of said second lens.
Claim 34
Dependent Claim 20 words
An optical system as described in claim 28 further comprising: a. means for detecting light which passes through said filter.
Claim 35
Dependent Claim 32 words
An optical system as described in claim 29 further comprising: a. means for collecting light which passes through said filter and b. means for directing the collected light to said detecting means.
Claim 36
Dependent Claim 44 words
An optical system as described in claim 28 wherein said collecting means and said directing means comprises: a. an elliptical mirror having the concentric center of the dielectric filter located at one focal point and said detecting means located at the other focal point.

References Cited (Backward Citations)

US3278752A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-01-21 1983-07-23 1984-01-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-01-21 1987-07-23 1988-01-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-01-21 1991-07-23 1992-01-22 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag