Abstract: A self-mixing interferometry sensor module, comprising a light emitter (LE), a detector unit (DU) and an optical element (OE), wherein the light emitter (LE) is operable to emit coherent electromagnetic radiation towards an external object (ET) 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. The detector unit (DU) is operable to generate output signals indicative of an optical power output of the light emitter (LE) due to the SMI. The optical element (OE) is aligned with respect to the light emitter (LE) such that a first fraction of electromagnetic radiation is directed towards the external target (ET) or the light emitter (LE) and a second fraction of electromagnetic radiation is directed towards the detector unit (DU). An optical power ratio determined by the first and second fractions meets a pre-determined value.

Abstract: A self-mixing interferometry sensor module, comprising a light emitter (LE), a detector unit (DU) and an optical element (OE), wherein the light emitter (LE) is operable to emit coherent electromagnetic radiation towards an external object (ET) 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. The detector unit (DU) is operable to generate output signals indicative of an optical power output of the light emitter (LE) due to the SMI. The optical element (OE) is aligned with respect to the light emitter (LE) such that a first fraction of electromagnetic radiation is directed towards the external target (ET) or the light emitter (LE) and a second fraction of electromagnetic radiation is directed towards the detector unit (DU). An optical power ratio determined by the first and second fractions meets a pre-determined value.

Abstract: The present invention relates to a single photon source, comprising: a microcavity arranged between a concave first minor and a semiconductor heterostructure forming a planar second minor, wherein the microcavity supports an optical mode, a quantum dot embedded in the semiconductor heterostructure and facing the first minor, and a laser light source configured to provide laser light in the microcavity to excite the quantum dot to emit single photons exiting the microcavity.