Patent ID: 11927441
Assignee: AMS INTERNATIONAL AG
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 17:
18. A self-mixing interferometry sensor module, comprising a light emitter, a detector unit and an optical element, wherein the light emitter is operable to:
emit coherent electromagnetic radiation towards an external object to be placed outside the sensor module; and
undergo self-mixing interference, SMI, caused by reflections of the emitted electromagnetic radiation from the external object back inside the sensor module; wherein the detector unit is operable to:
generate output signals indicative of an optical power output of the light emitter due to the SMI; wherein the optical element is aligned with respect to the light emitter such that:
a first fraction of electromagnetic radiation is directed towards the external target and/or the light emitter and a second fraction of electromagnetic radiation is directed towards the detector unit to generate the output signals, and such that
an optical power ratio of the first and second fractions meets a pre-determined value,
wherein the optical element comprises a ball lens.