Patent ID: 11892396
Assignee: DRäGER SAFETY AG & CO. KGAA
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 10:
11. Adaptable filter system for a gas sensor, wherein the adaptable filter system comprises
a first optical filter and
a second optical filter,
wherein the first filter is operable to switch between a first reference state in which the first filter passes light according to a first reference wavelength profile and a first measurement state in which the first filter passes light according to a first measurement wavelength profile,
wherein the second filter is operable, independently of the first filter, to switch between a second reference state in which the second filter passes light according to a second reference wavelength profile and a second measurement state in which the second filter passes light according to a second measurement wavelength profile,
wherein the first reference wavelength profile is different from the second reference wavelength profile, the first and second filters, thereby being switchable between four different composite states, the four composite states comprising:
a first composite state in which the first and second filters, are in the first and second reference states respectively,
a second composite state in which the first filter is in the first reference state and the second filter is in the second measurement state,
a third composite state in which the first filter is in the first measurement state and the second filter is in the second reference state, and
a fourth composite state in which the first and second filters, are in the first and second measurement states respectively.