Photoacoustic measurement setup and method for detecting a gas

A photoacoustic measurement setup, comprising:

• an infrared radiator, the infrared radiator being suitable for radiating broadband light with periodically modulated intensity, the infrared radiator including at least two heaters,
• wherein the infrared radiator is configured to change an excitation spectra of the radiated broadband light, wherein the infrared radiator is suitable to heat a gas volume with the broadband light and to generate an acoustic wave within the gas volume, and
• an acoustic sensor, the acoustic sensor being suitable for measuring the acoustic wave generated, wherein the excitation spectra emitted by the infrared radiator is changed by changing a temperature of the infrared radiator, and
• wherein the excitation spectra emitted by the infrared radiator is changed by a periodic intensity modulation of at least one heater being phase-shifted with respect to the periodic intensity modulation of at least one other heater.

A photoacoustic measurement setup, comprising:

• an infrared radiator, the infrared radiator being suitable for radiating broadband light with periodically modulated intensity,
• wherein the infrared radiator is configured to change an excitation spectra of the radiated broadband light, wherein the infrared radiator is suitable to heat a gas volume with the broadband light and to generate an acoustic wave within the gas volume, and
• an acoustic sensor, the acoustic sensor being suitable for measuring the acoustic wave generated,
• wherein the gas volume is located between the infrared radiator and a photoacoustic cell, and
• wherein a reference gas and the acoustic sensor are arranged in the photoacoustic cell.

A photoacoustic measurement setup, comprising:

• an infrared radiator, the infrared radiator being suitable for radiating broadband light with periodically modulated intensity, the infrared radiator including at least two individually controllable heaters,
• wherein the infrared radiator is configured to change an excitation spectra of the radiated broadband light, wherein the infrared radiator is suitable to heat a gas volume with the broadband light and to generate an acoustic wave within the gas volume,
• an acoustic sensor, the acoustic sensor being suitable for measuring the acoustic wave generated,
• a memory, at least one reference spectrum being stored therein, and
• a control and evaluation unit which is designed to compare the reference spectrum with the measured values and to assign a content of the gas volume to a gas or a gas mixture and/or to determine a concentration of a gas mixture and to control the infrared radiator.

A photoacoustic measurement setup, comprising:

• an infrared radiator, the infrared radiator being suitable for radiating broadband light with periodically modulated intensity,
• wherein the infrared radiator is configured to change an excitation spectra of the radiated broadband light, wherein the infrared radiator is suitable to heat a gas volume with the broadband light and to generate an acoustic wave within the gas volume, and
• an acoustic sensor, the acoustic sensor being suitable for measuring the acoustic wave generated,
• wherein the infrared radiator comprises at least two heaters,
• wherein the excitation spectra emitted by the infrared radiator is changed by a periodic intensity modulation of at least one heater being phase-shifted with respect to the periodic intensity modulation of at least one other heater,
• wherein the gas volume and the acoustic sensor are arranged in a photoacoustic cell, and
• wherein the heaters are arranged outside the photoacoustic cell.