ENVIRONMENT SENSOR, MEASURING DEVICE AND METHOD FOR OPERATING A MEASURING DEVICE

In at least one embodiment, the environment sensor for sensing at least one environment parameter includes a semiconductor layer sequence, a sheath, the index of refraction of which changes as a function of the environment parameter, and a first electrical contact and a second electrical contact for supplying current to the semiconductor layer sequence. The semiconductor layer sequence has the shape of a generalized cylinder having a main axis. In directions perpendicular to the main axis, the semiconductor layer sequence is at least partly covered by the sheath. The semiconductor layer sequence has an index of refraction which is greater than the index of refraction of the sheath. The semiconductor layer sequence is designed to form laser modes within the environment sensor. Furthermore, the environment sensor is designed such that, in its normal operation, a change in the index of refraction of the sheath causes a change in the electrical resistance of the semiconductor layer sequence as a result of a change in radiation losses within the semiconductor layer sequence.