An optical coherence tomography microscopy apparatus for detecting a three-dimensional image of an optically translucent or reflective sample object, the apparatus comprising an interferometric optical setup including - a light source comprising one or more light emitting elements, to emit a beam of light having an emission bandwidth, - a photo sensor unit including at least one photo sensor able to sense a light intensity in a sensing region and to generate a sense signal (Si) indicative for said light intensity, the sensed light intensity being dependent on interference in said sensing region between a first and a second sub-beam (B1, B2) impingent on the sensing region, and that are split off from said emitted beam, said first sub-beam being directed along a first optical path extending from the light source to the sensing region via the optically translucent or reflective sample object, and the second sub-beam being directed along a second optical path extending from the light source to the sensing region via the optically translucent or reflective reference object, - a displacement unit to change a difference in path length between said first optical path and said second optical path, therewith causing a modulation in the sensed light intensity, - a displacement sensor to generate a displacement signal indicative for said change in said path length difference, which displacement sensor includes a photo sensor to measure a temporal change in interference in a sensing bandwidth narrower than said emission bandwidth, said interference occurring between a third sub-beam being directed along a third optical path including the sample object and a fourth sub-beam directed along a fourth optical path including the reference object; and - a reference signal generator to generate a detection reference signal (Sr) from the displacement signal; - a demodulator to demodulate the sense signal, the demodulator comprising a detector using said detection reference signal (Sr) to sample the sense signal (Si), characterized in that said first, second, third and fourth sub-beam originate from the common light source, wherein a path length difference between the third and the fourth optical path changes corresponds to said changing difference between the path length of the first optical path and the path length of the second optical path. - a light source comprising one or more light emitting elements, to emit a beam of light having an emission bandwidth, - a photo sensor unit including at least one photo sensor able to sense a light intensity in a sensing region and to generate a sense signal (Si) indicative for said light intensity, the sensed light intensity being dependent on interference in said sensing region between a first and a second sub-beam (B1, B2) impingent on the sensing region, and that are split off from said emitted beam, said first sub-beam being directed along a first optical path extending from the light source to the sensing region via the optically translucent or reflective sample object, and the second sub-beam being directed along a second optical path extending from the light source to the sensing region via the optically translucent or reflective reference object, - a displacement unit to change a difference in path length between said first optical path and said second optical path, therewith causing a modulation in the sensed light intensity, - a displacement sensor to generate a displacement signal indicative for said change in said path length difference, which displacement sensor includes a photo sensor to measure a temporal change in interference in a sensing bandwidth narrower than said emission bandwidth, said interference occurring between a third sub-beam being directed along a third optical path including the sample object and a fourth sub-beam directed along a fourth optical path including the reference object; and - a reference signal generator to generate a detection reference signal (Sr) from the displacement signal; - a demodulator to demodulate the sense signal, the demodulator comprising a detector using said detection reference signal (Sr) to sample the sense signal (Si), characterized in that said first, second, third and fourth sub-beam originate from the common light source, wherein a path length difference between the third and the fourth optical path changes corresponds to said changing difference between the path length of the first optical path and the path length of the second optical path.