DiodeArrayTechnology/OriginalUSPatentDescriptionSummary
An aspect of heat in materials is thermal agitation electrical noise known as Johnson Noise. Thermal agitation generates a random movement of charges or currents in an infinite range of time intervals. In a circuit, the developed power of a noise source is P = 4KT.DELTA.f, where K is Bolzmann's constant, T is the absolute temperature of the circuit in which the noise appears, and .DELTA.f is the bandwidth defined. While this formula represents the developed power of a noise source, the internal resistance of the noise source permits a maximum available power to be abstracted that is only one-fourth the developed power of P = KT.DELTA.f; Fink, D. G. Radar Engineering, pp. 130-131, (1st Ed.), McGraw-Hill.
Johnson Noise behaves like an external signal and can be sorted, that is, preferentially conducted in one direction by a diode. Since the random movement of charges or currents in a circuit is bidirectional, the maximum power available from a rectified circuit is 1/2KT.DELTA.f where the internal resistance is matched to an external load. Allowance in the formula is then made for imperfect rectification resulting in the form 1/2KT.DELTA.fe where e is the efficiency. A plurality of rectified noise sources arranged in parallel in an array generates a resultant polarized output current that is cumulative. Thus, total power available in an array of rectified noise sources can be expressed by the formula P = 1/2KT.DELTA.fNe, where N is the number of rectified noise sources in the array. Broadly stated, the present invention comprises combining a plurality of rectifiers having an internal noise source to generate a d.c. output.
This can be accomplished by combining a plurality of sensitive low capacitance diodes having a broad bandwidth response. Within this category of diodes is the multiple cold cathodes common anode vacuum tube variation. However, to generate a meaningful output power from this combination, arrays containing diodes in the millions are preferred.
The recent development of two technically unrelated products when combined, can allow the fabrication of diodes having a sufficiently short response time, hence wide bandwidth, to be arranged in sufficiently large numbers to make generation of power by this method feasible. Concurrent with the generation of power, this combination as a result of its operation absorbs heat and provides refrigeration.
These two developments comprise the ultrafiltration screen membrane and the metal-metal diode. The ultrafiltration membrane is made from a mixture of volatile and non-volatile plastics which form a tessellation of uniform small cylindrical pores. These membranes can be fabricated with 250 A pores with 50 A walls and 100 um thick. The metal-metal diode is capable of rectifying frequencies conservatively up to 10.sup.12 Hz. Construction of a diode array by electroplating diode materials in the pores of the membrane such that each pore isolates an individual diode forms a combination that is capable of producing several watts of power per square meter.
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