Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
131 words
A plural-wavelength infrared detector device comprising a group of infrared detector elements formed in a lower level of material on a substrate, a group of upper-level detector elements mounted on the lower level and having an infrared response different from the lower-level elements, and a group of infrared concentrators associated with the elements in such an arrangement that each concentrator serves to collect incident infrared radiation over an area larger than an active portion of the associated element and to concentrate the collected radiation onto the active portion of that element, each upper-level element having at least one electrical connection which extends to the substrate through an area of the lower level which is located between the lower-level active portions on which the infrared radiation is concentrated by the associated concentrators.
Claim 2
Dependent Claim
131 words
A plural-wavelength infrared detector device comprising a group of infrared detector elements formed in a lower level of material on a substrate, a group of upper-level detector elements mounted on the lower level and having an infrared response different from the lower-level elements, and a group of infrared concentrators associated with the elements in such an arrangement that each concentrator serves to collect incident infrared radiation over an area larger than an active portion of the associated element and to concentrate the collected radiation onto the active portion of that element, each upper-level element having at least one electrical connection which extends to the substrate through an area of the lower level which is located between the lower-level active portions on which the infrared radiation is concentrated by the associated concentrators.
Claim 3
Dependent Claim
47 words
A detector device as claimed in Claim 1, characterised in that the lower-level elements are each located below a respective upper-level element, and in that a respective concentrator serves to concentrate the infrared on the active portions of both the upper-level element and the underlying lower-level element.
Claim 4
Dependent Claim
32 words
A detector device as claimed in Claim 2, characterised in that each element comprises a separate island of infrared-sensitive material, and in that the upper-level islands are carried on the lower-level islands.
Claim 5
Dependent Claim
31 words
A detector device as claimed in Claim 1, characterised in that, as seen in plan view at the surface of the substrate, the lower-level elements are located between the upper-level elements.
Claim 6
Dependent Claim
42 words
A detector device as claimed in any one of Claims 1, 2 or 4, further characterised in that each group of the elements is formed in a layer of a respective infrared-sensitive material, the upper-level layer being carried on the lower-level layer.
Claim 7
Dependent Claim
42 words
A detector device as claimed in any one of the preceding claims, characterised in that both the upper-level and lower-level elements each have a p-n junction in infrared-sensitive semiconductor material, the material of one level having a smaller bandgap than the other.
Claim 8
Dependent Claim
50 words
A detector device as claimed in Claim 6, characterised in that one of the electrical connections of each upper-level element extends to the substrate on a further region of the lower-level semiconductor material, which further region is separated by a p-n junction from the detector-element p-n junction in the lower-level.
Claim 9
Dependent Claim
38 words
A detector device as claimed in any one of the preceding claims, characterised in that at least one connection of each upper-level element extends to the substrate on an insulated side-wall of a portion of the lower-level material.
Claim 10
Dependent Claim
53 words
A detector device as claimed in any one of the preceding claims, characterised in that, for each upper-level element, there is provided a separate island of the lower-level infrared sensitive material which is located between lower-level detector elements and via which at least one connection of each upper-level element extends to the substrate.
Claim 11
Dependent Claim
39 words
A detector device as claimed in any one of the preceding claims, characterised in that the group of infrared concentrators is present in front of the elements to concentrate the incident radiation onto the active areas of the elements.