The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 14, 2023
Filed:
Mar. 06, 2019
Bae Systems Plc, London, GB;
Mark Edgar Bray, Chelmsford, GB;
BAE SYSTEMS PLC, London, GB;
Abstract
An optical filter includes a first layer including a first notch filter arranged to attenuate electromagnetic radiation having a first wavelength λincident normally thereupon. The optical filter includes a second layer including a second notch filter arranged to attenuate electromagnetic radiation having a second wavelength λincident normally thereupon. The first wavelength λand the second wavelength λare different. The second layer is stacked upon the first layer. In use, the first notch filter attenuates the electromagnetic radiation having a predetermined wavelength λ incident thereupon at a first angle of incidence θand the second notch filter attenuates the electromagnetic radiation having the predetermined wavelength λ incident thereupon at a second angle of incidence θ, wherein the first angle of incidence θand the second angle of incidence θare different.