Asymmetric dual-mode ionization systems and methods

An asymmetric dual-mode ionization measurement method comprising:

• receiving an indication of a first mode or a second mode;
• coupling a high-voltage potential to a first high-voltage plate of an ionization chamber when the first mode is indicated, wherein the first high-voltage plate is separated from an readout plate by a first gap;
• coupling the high-voltage potential to a second high-voltage plate of the ionization chamber when the second mode is indicated, wherein the second high-voltage plate is separated from the readout plate by a second gap;
• passing an ionizing radiation having a first density range through the ionization chamber when the first mode is indicated;
• passing an ionizing radiation have a second density range through the ionization chamber when the second mode is indicated;
• and
• measuring ion charge on the readout plate when the ionization mode control signal is in the first state, wherein the ion charge is generated by the ionizing radiation passing through the ionization chamber;
• measuring the ion charge on the readout plate when the ionization mode control signal is in the second state, wherein the ion charge is generated by the ionizing radiation passing through the ionization chamber;
• and
• outputting a measurement of the radiation rate of the ionizing radiation determined as a function of the measured ion charge and the state of the ionization mode signal.

A radiation therapy system comprising:

• a particle or energy source;
• a beam transport system coupled to the particle or energy source;
• a beam applicator coupled to the beam transport system;
• and
• an ionization chamber measurement system coupled to the beam applicator, wherein the ionization chamber measurement system includes;
• a high-voltage supply configured to generate a high-voltage potential;
• an readout plate, wherein the readout plate is coupled to an ion charge measurement circuit;
• a first high-voltage plate disposed to form a first active volume between the first high-voltage plate and the readout plate, wherein a particle radiation stream is configured to pass through the first active volume;
• a second high-voltage plate disposed to form a second active volume between second high-voltage plate and the readout plate, and wherein the particle radiation stream is configured to pass through the second active volume;
• a switch matrix configured to couple the high-voltage potential to the first high-voltage plate during a first mode, and couple the high-voltage potential to the second high-voltage plate during a second mode;
• and
• the ion charge measurement circuit coupled to the readout plate and configured to measure ions generated by the ionizing radiation passing through the first active volume during the first mode and measure ions generated by the ionizing radiation passing through the second active volume during the second mode.