Frequency independent beam waveguide

• US 4,749,244 A
• Filed: 11/28/1986
• Issued: 06/07/1988
• Est. Priority Date: 11/28/1986
• Status: Expired due to Fees

• Current Assignee: Space Systems/Loral Incorporated (Loral Space and Communications Incorporated)
• Original Assignee: Ford Aerospace & Communications Corporation (Galileo Parent, Inc.)
• Inventors: Luh, Howard H.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Ham, Seung
• Application Number:
  US06/935,891
• Time in Patent Office: 557 Days
• Field of Search: 350/96.10, 350/96.29, 350/96.28, 350/573, 350/619, 343/909
• US Class Current: 385/147
• CPC Class Codes: G02B 6/10 of the optical waveguide type G02B6/02, G02B6/24 take precedence; devices or arrangements for the control of light by electric, magnetic, electro-magnetic or acoustic means G02F1/00; transferring the modulation of modulated light G02F2/00; optical logic elements G02F3/00; optical analogue/digital converters G02F7/00
• CPC Class Codes: H01P 3/20 Quasi-optical arrangements for guiding a wave, e.g. focusing by dielectric lenses

Abstract

A frequency independent beam waveguide comprises a row of equispaced identical axisymmetric phase setting means (1), which may be lenses or reflectors, or a combination of both, spaced a distance D apart from each other. The focal length of each phase setting means (1) is D/2. A launcher (2) spaced a distance D away from the first phase setting means (1A) in the row emits a beam of electromagnetic energy in the direction of said row. The phase and amplitude distribution in the cross-section (A) of the beam at the mouth of the launcher (2) is duplicated every other phase setting means (1) along the row (at locations B), independent of the frequency of the launched beam. As a result, the beam propagates along the row.

Claims

1. A quasi-infinitely broadbanded beam waveguide comprising a row of several phase setting means spaced a distance D apart from each other;

and

a launcher for emitting a beam of electromagnetic energy in the direction of the row of phase setting means;

wherein

the focal length of each phase setting means is D/2;

the launcher is spaced a distance D away from the first phase setting means in the row;

the wavelength of the beam is very small compared with the diameter of each phase setting means; and

the phase and amplitude distribution in the cross-section of the beam at the launcher is duplicated every other phase setting means, independent of the frequency of the launched beam;

whereby

the beam propagates along the row, independent of frequency.

2. The beam waveguide of claim 1 wherein the beam emitted by the launcher varies in frequency;

and

the locations of phase distribution duplication and resulting propagation of the beam are substantially independent of frequency.

3. The beam waveguide of claim 1 wherein at least some

phase setting means are lenses.

4. The beam waveguide of claim 1 wherein at least some

phase setting means are reflectors.

5. The beam waveguide of claim 1 wherein the launcher comprises a corrugated horn.

6. The beam waveguide of claim 1 wherein the phase setting means are all identical, and each phase setting means is symmetrical about an axis that is orthogonal to the direction of propagation of the electromagnetic beam.