An enhanced vision system includes an image intensifier that includes a phosphor screen. The phosphor screen includes a thin-film phosphor layer deposited, patterned, transferred, or otherwise disposed on the substrate using a thin-film deposition technique. A conductive layer is deposited across at least a portion of the phosphor layer. The relatively smooth morphology of the phosphor layer beneficially permits the use of a relatively thin conductive layer. The use of a relatively thin conductive layer advantageously reduces the operating voltage between an electron multiplier and the phosphor screen. A secondary electron emitter may be disposed across at least a portion of the conductive layer.
H01L 33/44 - SEMICONDUCTOR DEVICES NOT COVERED BY CLASS - Details thereof characterised by the coatings, e.g. passivation layer or anti-reflective coating
H01J 31/50 - Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output
H01J 29/28 - Luminescent screens with protective, conductive, or reflective layers
C23C 16/455 - Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for introducing gases into the reaction chamber or for modifying gas flows in the reaction chamber
G02B 6/04 - Light guidesStructural details of arrangements comprising light guides and other optical elements, e.g. couplings formed by bundles of fibres
2.
Dual-spectrum photocathode for image intensification
A dual-spectrum photocathode capable of emitting photo-electrons into a first vacuum space includes a first photodetector array formed using a first optoelectronic material that generates photo-electrons responsive to incident electromagnetic energy in a first spectral band. The dual-spectrum photocathode also includes a second photodetector array formed using a second optoelectronic material that generates photo-electrons responsive to incident electromagnetic energy in a second spectral band that is different from the first spectral band. The first spectral band may include the visible electromagnetic spectrum between 390 nanometers and 700 nanometers and the second spectral band may include the short-wave infrared (SWIR) electromagnetic spectrum above 900 nanometers.
H01J 9/12 - Manufacture of electrodes or electrode systems of photo-emissive cathodesManufacture of electrodes or electrode systems of secondary-emission electrodes
H01J 31/50 - Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output
Image intensifiers may include a photocathode that emits photoelectrons in proportion to the rate photons impact the photocathode. The photoelectrons are multiplied using a microchannel plate that includes a plurality of microchannels. Photoelectrons are scattered by the microchannel plate when the photoelectrons strike the surface of the microchannel plate rather than enter one of the microchannels. Electron scatter within an image intensifier results in a halo or bloom around bright or luminous objects. Halo or bloom may be minimized by reducing the electron scatter within the image intensifier. Deposition of an anti-scattering layer on the surface of the microchannel plate within the image intensifier can absorb photoelectrons that fail to enter a microchannel and may thus reduce the incidence of halo or bloom.
An enhanced vision system includes a first optic subsystem and a transparent photodetector subsystem disposed within a common housing. The first optic subsystem may include passive devices such as simple or compound lenses, active devices such as low-light enhancing image intensifiers, or a combination of passive and active devices. The transparent photodetector subsystem receives the visible image exiting the first optic subsystem and converts a portion of the electromagnetic energy in the visible image to a signal communicated to image analysis circuitry. On a real-time or near real-time basis, the image analysis circuitry detects and identifies structures, objects, and/or individuals in the visible image. The image analysis circuitry provides an output that includes information regarding the structure, objects, and individuals to the system user contemporaneous with the system user viewing the visible image.