Abstract This invention is a resonant waveguide Stark cell suitable for use in a Stark-modulated microwave spectrometer. The cell is constructed from a short length of waveguide. A Stark electrode is located inside the waveguide parallel to the broad face of the guide and insulated from the walls of the guide with narrow teflon strips. A reflector with a small coupling iris at its center is located at one end of the cell. This small coupling iris is for passing microwave energy into and out of the cell. At the other end of the cell there is an adjustable waveguide short making the small Stark cell into a tuneable cavity which can be tuned for resonance at selected microwave frequencies. Means are provided for maintaining a gas-tight compartment within the cell, and ports are provided for the introduction of the gas to be analyzed into the gas-tight compartment.
A resonant waveguide Stark cell for use in a Stark modulated microwave spectrometer comprising: a waveguide cavity whose sides are made from an electrically conductive material, said sides forming a first electrode for said Stark cell; a first microwave reflector located at one end of said cavity; a small coupling iris in said first microwave reflector for allowing microwave energy to flow into and out of said cavity; a second microwave reflector located at the other end of said cavity; means for maintaining a gas-tight compartment within said cavity without appreciably interferring with the flow of the microwave energy; and ports in said sides of said cavity for allowing sample gas to flow into and out of said compartment.
Claim 2
Dependent Claim
119 words
A resonant waveguide Stark cell for use in a Stark modulated microwave spectrometer comprising: a waveguide cavity whose sides are made from an electrically conductive material, said sides forming a first electrode for said Stark cell; a first microwave reflector located at one end of said cavity; a small coupling iris in said first microwave reflector for allowing microwave energy to flow into and out of said cavity; a second microwave reflector located at the other end of said cavity; means for maintaining a gas-tight compartment within said cavity without appreciably interferring with the flow of the microwave energy; and ports in said sides of said cavity for allowing sample gas to flow into and out of said compartment.
Claim 3
Dependent Claim
19 words
A Stark cell according to claim 1 including means for tuning said cavity for resonance at selected microwave frequencies.
Claim 4
Dependent Claim
25 words
A Stark cell according to claim 2 wherein said tuning means is means for moving said second microwave reflector along the sides of said cavity.
Claim 5
Dependent Claim
32 words
A Stark cell according to claim 2 wherein said means for maintaining a gas-tight compartment within said cavity includes a window highly transparent to microwave energy at each end of said compartment.
Claim 6
Dependent Claim
25 words
A Stark cell according to claim 2 including means for applying Stark voltages to said Stark electrode and for connecting said first electrode to ground.
Claim 7
Dependent Claim
30 words
A Stark cell according to claim 5 including means for applying microwave energy to said Stark cell through said small coupling iris and for removing microwave energy from said cell.
Claim 8
Dependent Claim
19 words
A Stark cell according to claim 6 including means for demodulating the microwave energy removed from said Stark cell.