A sensor device (340) for determining a flow characteristic of an object (341) being movable in an element (342) comprises a light emitting unit (344) configured for emitting light towards the element (342) and a light detecting unit (344) configured for detecting light scattered back from the element (342). The sensor device (340) comprises an optical unit (346) configured for spatially separating a light incidence element portion (348) of the element (342) and a light detection element portion (350) of the element (342) from one another, wherein the light incidence element portion (348) is associated with the emitted light inciding on the element (342) and the light detection element portion (350) is associated with the back-scattered light scattered back from the element (342) for detection. The sensor device (340) comprises a determining unit (358) configured for determining the flow characteristic of the object (341) being movable in the element (342) based on light indicative of the emitted light and the detected back-scattered light. The sensor device (340) allows for an accurate and easy determination of the flow characteristic of the object (341).
