Apparatus for detecting coherent radiant energy

Claim 2

Apparatus for distinguishing between coherent and incoherent radiant energy comprising first and second elements formed of a material having energy states into which radiant energy incident upon said materials is absorbed at least in part as a non-linear function of the intensity of said radiant energy, and producing electrical output signals in response to said part of said incident radiant energy absorbed thereby, focusing means disposed such that the focal spot thereof is encompassed by said first element whereby the intensity of coherent radiant energy incident upon said apparatus is made to be higher in said first element than in said second element, and signal processing means coupled to the electrical outputs of said first and second elements.

Claim 3

Apparatus as recited in claim 1 wherein said signal processing means comprises a difference network which produces an output only in response to a difference between the outputs of said first and second elements.

Claim 4

Apparatus as recited in claim 1 wherein said material is an acentric crystalline compound.

Claim 5

Apparatus as recited in claim 3 wherein said compound is selected from the oxides, sulfides, selenides and tellurides of the metallic group II B elements of the periodic table.

Claim 6

Apparatus as recited in claim 4 wherein said compound is selected from the group of II B - VI A compounds consisting of zinc selenide, zinc oxide, cadmium sulfide, and cadmium sulfide selenide.

Claim 7

An improved detector of coherent radiant energy comprising in combination focusing means, a photodetector, an element having energy states into which radiant energy incident upon said element is absorbed at least in part as a non-linear function of the intensity of said radiant energy, and signal processing means, said photodetector being disposed at the focus of said focusing means, and producing an output in response to radiant energy incident thereon, said element being disposed between said focusing means and said photodetector, and producing an electrical output in response to said part of said incident radiant energy absorbed thereby, said photodetector output and said element output being electrically coupled to said signal processing means whereby an output signal is produced in response to radiant energy impingent upon said focusing means which is of an intensity in excess of that which would tend to saturate said photodetector.

Claim 8

An improved detector of coherent radiant energy comprising in combination focusing means, a photodetector, an element having energy states into which radiant energy incident upon said element is absorbed at least in part as a non-linear function of the intensity of said radiant energy, and signal processing means, said photodetector being disposed at the focus of said focusing means, and producing an output in response to radiant energy incident thereon, said element being disposed between said focusing means and said photodetector, and producing an electrical output in response to said part of said incident radiant energy absorbed thereby, said photodetector output and said element output being electrically coupled to said signal processing means whereby an output signal is produced in response to radiant energy impingent upon said focusing means which is of an intensity in excess of that which would tend to saturate said photodetector.

Claim 9

Apparatus as recited in claim 6 wherein said element is formed of an acentric crystalline compound.

Claim 10

Apparatus as recited in claim 7 wherein said compound is selected from the oxides, sulfides, selenides and tellurides of the metallic group II B elements of the periodic table.

Claim 11

Apparatus as recited in claim 8 wherein said compound is selected from the group of II B - VI A compounds consisting of zinc selenide, zinc oxide, cadmium sulfide, and cadmium sulfide selenide.

Claim 12

Apparatus as recited in claim 9 wherein said focusing means is a lens.